diff --git a/UPGRADE-5.3.md b/UPGRADE-5.3.md
index be36db0c14..e1e910e729 100644
--- a/UPGRADE-5.3.md
+++ b/UPGRADE-5.3.md
@@ -44,6 +44,8 @@ FrameworkBundle
  * Deprecate the `KernelTestCase::$container` property, use `KernelTestCase::getContainer()` instead
  * Rename the container parameter `profiler_listener.only_master_requests` to `profiler_listener.only_main_requests`
  * Deprecate registering workflow services as public
+ * Deprecate option `--xliff-version` of the `translation:update` command, use e.g. `--format=xlf20` instead
+ * Deprecate option `--output-format` of the `translation:update` command, use e.g. `--format=xlf20` instead
 
 HttpFoundation
 --------------
diff --git a/UPGRADE-6.0.md b/UPGRADE-6.0.md
index 68f1bf9419..25640765da 100644
--- a/UPGRADE-6.0.md
+++ b/UPGRADE-6.0.md
@@ -86,6 +86,8 @@ FrameworkBundle
  * Removed the `lock.RESOURCE_NAME` and `lock.RESOURCE_NAME.store` services and the `lock`, `LockInterface`, `lock.store` and `PersistingStoreInterface` aliases, use `lock.RESOURCE_NAME.factory`, `lock.factory` or `LockFactory` instead.
  * Remove the `KernelTestCase::$container` property, use `KernelTestCase::getContainer()` instead
  * Registered workflow services are now private
+ * Remove option `--xliff-version` of the `translation:update` command, use e.g. `--output-format=xlf20` instead
+ * Remove option `--output-format` of the `translation:update` command, use e.g. `--output-format=xlf20` instead
 
 HttpFoundation
 --------------
diff --git a/link b/link
index a56075840e..29f9600d6b 100755
--- a/link
+++ b/link
@@ -41,7 +41,7 @@ if (!is_dir("$pathToProject/vendor/symfony")) {
 $sfPackages = array('symfony/symfony' => __DIR__);
 
 $filesystem = new Filesystem();
-$braces = array('Bundle', 'Bridge', 'Component', 'Component/Security', 'Component/Mailer/Bridge', 'Component/Messenger/Bridge', 'Component/Notifier/Bridge', 'Contracts');
+$braces = array('Bundle', 'Bridge', 'Component', 'Component/Security', 'Component/Mailer/Bridge', 'Component/Messenger/Bridge', 'Component/Notifier/Bridge', 'Contracts', 'Component/Translation/Bridge');
 $directories = array_merge(...array_values(array_map(function ($part) {
     return glob(__DIR__.'/src/Symfony/'.$part.'/*', GLOB_ONLYDIR | GLOB_NOSORT);
 }, $braces)));
diff --git a/src/Symfony/Bundle/FrameworkBundle/CHANGELOG.md b/src/Symfony/Bundle/FrameworkBundle/CHANGELOG.md
index d2ce954777..27ce0f6b81 100644
--- a/src/Symfony/Bundle/FrameworkBundle/CHANGELOG.md
+++ b/src/Symfony/Bundle/FrameworkBundle/CHANGELOG.md
@@ -20,6 +20,8 @@ CHANGELOG
  * Rename the container parameter `profiler_listener.only_master_requests` to `profiler_listener.only_main_requests`
  * Add service `fragment.uri_generator` to generate the URI of a fragment
  * Deprecate registering workflow services as public
+ * Deprecate option `--xliff-version` of the `translation:update` command, use e.g. `--format=xlf20` instead
+ * Deprecate option `--output-format` of the `translation:update` command, use e.g. `--format=xlf20` instead
 
 5.2.0
 -----
diff --git a/src/Symfony/Bundle/FrameworkBundle/Command/TranslationUpdateCommand.php b/src/Symfony/Bundle/FrameworkBundle/Command/TranslationUpdateCommand.php
index cacf328451..c849538173 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Command/TranslationUpdateCommand.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Command/TranslationUpdateCommand.php
@@ -77,12 +77,13 @@ class TranslationUpdateCommand extends Command
                 new InputArgument('locale', InputArgument::REQUIRED, 'The locale'),
                 new InputArgument('bundle', InputArgument::OPTIONAL, 'The bundle name or directory where to load the messages'),
                 new InputOption('prefix', null, InputOption::VALUE_OPTIONAL, 'Override the default prefix', '__'),
-                new InputOption('output-format', null, InputOption::VALUE_OPTIONAL, 'Override the default output format', 'xlf'),
+                new InputOption('output-format', null, InputOption::VALUE_OPTIONAL, 'Override the default output format (deprecated)'),
+                new InputOption('format', null, InputOption::VALUE_OPTIONAL, 'Override the default output format', 'xlf12'),
                 new InputOption('dump-messages', null, InputOption::VALUE_NONE, 'Should the messages be dumped in the console'),
                 new InputOption('force', null, InputOption::VALUE_NONE, 'Should the update be done'),
                 new InputOption('clean', null, InputOption::VALUE_NONE, 'Should clean not found messages'),
                 new InputOption('domain', null, InputOption::VALUE_OPTIONAL, 'Specify the domain to update'),
-                new InputOption('xliff-version', null, InputOption::VALUE_OPTIONAL, 'Override the default xliff version', '1.2'),
+                new InputOption('xliff-version', null, InputOption::VALUE_OPTIONAL, 'Override the default xliff version (deprecated)'),
                 new InputOption('sort', null, InputOption::VALUE_OPTIONAL, 'Return list of messages sorted alphabetically', 'asc'),
                 new InputOption('as-tree', null, InputOption::VALUE_OPTIONAL, 'Dump the messages as a tree-like structure: The given value defines the level where to switch to inline YAML'),
             ])
@@ -112,8 +113,8 @@ You can sort the output with the <comment>--sort</> flag:
 
 You can dump a tree-like structure using the yaml format with <comment>--as-tree</> flag:
 
-    <info>php %command.full_name% --force --output-format=yaml --as-tree=3 en AcmeBundle</info>
-    <info>php %command.full_name% --force --output-format=yaml --sort=asc --as-tree=3 fr</info>
+    <info>php %command.full_name% --force --format=yaml --as-tree=3 en AcmeBundle</info>
+    <info>php %command.full_name% --force --format=yaml --sort=asc --as-tree=3 fr</info>
 
 EOF
             )
@@ -135,13 +136,31 @@ EOF
             return 1;
         }
 
+        $format = $input->getOption('output-format') ?: $input->getOption('format');
+        $xliffVersion = $input->getOption('xliff-version') ?? '1.2';
+
+        if ($input->getOption('xliff-version')) {
+            trigger_deprecation('symfony/framework-bundle', '5.3', 'The "--xliff-version" option is deprecated, use "--format=xlf%d" instead.', 10 * $xliffVersion);
+        }
+
+        if ($input->getOption('output-format')) {
+            trigger_deprecation('symfony/framework-bundle', '5.3', 'The "--output-format" option is deprecated, use "--format=xlf%d" instead.', 10 * $xliffVersion);
+        }
+
+        switch ($format) {
+            case 'xlf20': $xliffVersion = '2.0';
+            // no break
+            case 'xlf12': $format = 'xlf';
+        }
+
         // check format
         $supportedFormats = $this->writer->getFormats();
-        if (!\in_array($input->getOption('output-format'), $supportedFormats, true)) {
-            $errorIo->error(['Wrong output format', 'Supported formats are: '.implode(', ', $supportedFormats).'.']);
+        if (!\in_array($format, $supportedFormats, true)) {
+            $errorIo->error(['Wrong output format', 'Supported formats are: '.implode(', ', $supportedFormats).', xlf12 and xlf20.']);
 
             return 1;
         }
+
         /** @var KernelInterface $kernel */
         $kernel = $this->getApplication()->getKernel();
 
@@ -225,23 +244,7 @@ EOF
 
         $resultMessage = 'Translation files were successfully updated';
 
-        // move new messages to intl domain when possible
-        if (class_exists(\MessageFormatter::class)) {
-            foreach ($operation->getDomains() as $domain) {
-                $intlDomain = $domain.MessageCatalogueInterface::INTL_DOMAIN_SUFFIX;
-                $newMessages = $operation->getNewMessages($domain);
-
-                if ([] === $newMessages || ([] === $currentCatalogue->all($intlDomain) && [] !== $currentCatalogue->all($domain))) {
-                    continue;
-                }
-
-                $result = $operation->getResult();
-                $allIntlMessages = $result->all($intlDomain);
-                $currentMessages = array_diff_key($newMessages, $result->all($domain));
-                $result->replace($currentMessages, $domain);
-                $result->replace($allIntlMessages + $newMessages, $intlDomain);
-            }
-        }
+        $operation->moveMessagesToIntlDomainsIfPossible('new');
 
         // show compiled list of messages
         if (true === $input->getOption('dump-messages')) {
@@ -284,8 +287,8 @@ EOF
                 $extractedMessagesCount += $domainMessagesCount;
             }
 
-            if ('xlf' === $input->getOption('output-format')) {
-                $io->comment(sprintf('Xliff output version is <info>%s</info>', $input->getOption('xliff-version')));
+            if ('xlf' === $format) {
+                $io->comment(sprintf('Xliff output version is <info>%s</info>', $xliffVersion));
             }
 
             $resultMessage = sprintf('%d message%s successfully extracted', $extractedMessagesCount, $extractedMessagesCount > 1 ? 's were' : ' was');
@@ -306,7 +309,7 @@ EOF
                 $bundleTransPath = end($transPaths);
             }
 
-            $this->writer->write($operation->getResult(), $input->getOption('output-format'), ['path' => $bundleTransPath, 'default_locale' => $this->defaultLocale, 'xliff_version' => $input->getOption('xliff-version'), 'as_tree' => $input->getOption('as-tree'), 'inline' => $input->getOption('as-tree') ?? 0]);
+            $this->writer->write($operation->getResult(), $format, ['path' => $bundleTransPath, 'default_locale' => $this->defaultLocale, 'xliff_version' => $xliffVersion, 'as_tree' => $input->getOption('as-tree'), 'inline' => $input->getOption('as-tree') ?? 0]);
 
             if (true === $input->getOption('dump-messages')) {
                 $resultMessage .= ' and translation files were updated';
@@ -335,11 +338,13 @@ EOF
         foreach ($catalogue->getResources() as $resource) {
             $filteredCatalogue->addResource($resource);
         }
+
         if ($metadata = $catalogue->getMetadata('', $intlDomain)) {
             foreach ($metadata as $k => $v) {
                 $filteredCatalogue->setMetadata($k, $v, $intlDomain);
             }
         }
+
         if ($metadata = $catalogue->getMetadata('', $domain)) {
             foreach ($metadata as $k => $v) {
                 $filteredCatalogue->setMetadata($k, $v, $domain);
diff --git a/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Compiler/UnusedTagsPass.php b/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Compiler/UnusedTagsPass.php
index 3590d0074c..5558e3cfe8 100644
--- a/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Compiler/UnusedTagsPass.php
+++ b/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Compiler/UnusedTagsPass.php
@@ -85,6 +85,7 @@ class UnusedTagsPass implements CompilerPassInterface
         'translation.dumper',
         'translation.extractor',
         'translation.loader',
+        'translation.provider_factory',
         'twig.extension',
         'twig.loader',
         'twig.runtime',
diff --git a/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Configuration.php b/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Configuration.php
index a49f29ef3b..2f0d24dd85 100644
--- a/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Configuration.php
+++ b/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Configuration.php
@@ -785,6 +785,7 @@ class Configuration implements ConfigurationInterface
                     ->fixXmlConfig('fallback')
                     ->fixXmlConfig('path')
                     ->fixXmlConfig('enabled_locale')
+                    ->fixXmlConfig('provider')
                     ->children()
                         ->arrayNode('fallbacks')
                             ->info('Defaults to the value of "default_locale".')
@@ -822,6 +823,27 @@ class Configuration implements ConfigurationInterface
                                 ->end()
                             ->end()
                         ->end()
+                        ->arrayNode('providers')
+                            ->info('Translation providers you can read/write your translations from')
+                            ->useAttributeAsKey('name')
+                            ->prototype('array')
+                                ->fixXmlConfig('domain')
+                                ->fixXmlConfig('locale')
+                                ->children()
+                                    ->scalarNode('dsn')->end()
+                                    ->arrayNode('domains')
+                                        ->prototype('scalar')->end()
+                                        ->defaultValue([])
+                                    ->end()
+                                    ->arrayNode('locales')
+                                        ->prototype('scalar')->end()
+                                        ->defaultValue([])
+                                        ->info('If not set, all locales listed under framework.translator.enabled_locales are used.')
+                                    ->end()
+                                ->end()
+                            ->end()
+                            ->defaultValue([])
+                        ->end()
                     ->end()
                 ->end()
             ->end()
diff --git a/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/FrameworkExtension.php b/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/FrameworkExtension.php
index 7e37224962..9cddc28f86 100644
--- a/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/FrameworkExtension.php
+++ b/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/FrameworkExtension.php
@@ -169,6 +169,7 @@ use Symfony\Component\Serializer\Normalizer\UnwrappingDenormalizer;
 use Symfony\Component\Stopwatch\Stopwatch;
 use Symfony\Component\String\LazyString;
 use Symfony\Component\String\Slugger\SluggerInterface;
+use Symfony\Component\Translation\Bridge\Loco\Provider\LocoProviderFactory;
 use Symfony\Component\Translation\Command\XliffLintCommand as BaseXliffLintCommand;
 use Symfony\Component\Translation\PseudoLocalizationTranslator;
 use Symfony\Component\Translation\Translator;
@@ -1222,11 +1223,14 @@ class FrameworkExtension extends Extension
         if (!$this->isConfigEnabled($container, $config)) {
             $container->removeDefinition('console.command.translation_debug');
             $container->removeDefinition('console.command.translation_update');
+            $container->removeDefinition('console.command.translation_pull');
+            $container->removeDefinition('console.command.translation_push');
 
             return;
         }
 
         $loader->load('translation.php');
+        $loader->load('translation_providers.php');
 
         // Use the "real" translator instead of the identity default
         $container->setAlias('translator', 'translator.default')->setPublic(true);
@@ -1348,6 +1352,46 @@ class FrameworkExtension extends Extension
                     $options,
                 ]);
         }
+
+        $classToServices = [
+            LocoProviderFactory::class => 'translation.provider_factory.loco',
+        ];
+
+        $parentPackages = ['symfony/framework-bundle', 'symfony/translation', 'symfony/http-client'];
+
+        foreach ($classToServices as $class => $service) {
+            $package = sprintf('symfony/%s-translation', substr($service, \strlen('translation.provider_factory.')));
+
+            if (!$container->hasDefinition('http_client') || !ContainerBuilder::willBeAvailable($package, $class, $parentPackages)) {
+                $container->removeDefinition($service);
+            }
+        }
+
+        if (!$config['providers']) {
+            return;
+        }
+
+        foreach ($config['providers'] as $name => $provider) {
+            if (!$config['enabled_locales'] && !$provider['locales']) {
+                throw new LogicException(sprintf('You must specify one of "framework.translator.enabled_locales" or "framework.translator.providers.%s.locales" in order to use translation providers.', $name));
+            }
+        }
+
+        $container->getDefinition('console.command.translation_pull')
+            ->replaceArgument(4, array_merge($transPaths, [$config['default_path']]))
+            ->replaceArgument(5, $config['enabled_locales'])
+        ;
+
+        $container->getDefinition('console.command.translation_push')
+            ->replaceArgument(2, array_merge($transPaths, [$config['default_path']]))
+            ->replaceArgument(3, $config['enabled_locales'])
+        ;
+
+        $container->getDefinition('translation.provider_collection_factory')
+            ->replaceArgument(1, $config['enabled_locales'])
+        ;
+
+        $container->getDefinition('translation.provider_collection')->setArgument(0, $config['providers']);
     }
 
     private function registerValidationConfiguration(array $config, ContainerBuilder $container, PhpFileLoader $loader, bool $propertyInfoEnabled)
diff --git a/src/Symfony/Bundle/FrameworkBundle/Resources/config/console.php b/src/Symfony/Bundle/FrameworkBundle/Resources/config/console.php
index 1c05d8760e..c076183cdc 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Resources/config/console.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Resources/config/console.php
@@ -46,6 +46,8 @@ use Symfony\Component\Messenger\Command\FailedMessagesRetryCommand;
 use Symfony\Component\Messenger\Command\FailedMessagesShowCommand;
 use Symfony\Component\Messenger\Command\SetupTransportsCommand;
 use Symfony\Component\Messenger\Command\StopWorkersCommand;
+use Symfony\Component\Translation\Command\TranslationPullCommand;
+use Symfony\Component\Translation\Command\TranslationPushCommand;
 use Symfony\Component\Translation\Command\XliffLintCommand;
 use Symfony\Component\Validator\Command\DebugCommand as ValidatorDebugCommand;
 
@@ -232,6 +234,26 @@ return static function (ContainerConfigurator $container) {
             ])
             ->tag('console.command')
 
+        ->set('console.command.translation_pull', TranslationPullCommand::class)
+            ->args([
+                service('translation.provider_collection'),
+                service('translation.writer'),
+                service('translation.reader'),
+                param('kernel.default_locale'),
+                [], // Translator paths
+                [], // Enabled locales
+            ])
+            ->tag('console.command', ['command' => 'translation:pull'])
+
+        ->set('console.command.translation_push', TranslationPushCommand::class)
+            ->args([
+                service('translation.provider_collection'),
+                service('translation.reader'),
+                [], // Translator paths
+                [], // Enabled locales
+            ])
+            ->tag('console.command', ['command' => 'translation:push'])
+
         ->set('console.command.workflow_dump', WorkflowDumpCommand::class)
             ->tag('console.command')
 
diff --git a/src/Symfony/Bundle/FrameworkBundle/Resources/config/schema/symfony-1.0.xsd b/src/Symfony/Bundle/FrameworkBundle/Resources/config/schema/symfony-1.0.xsd
index 44ba965b79..edcaca3a90 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Resources/config/schema/symfony-1.0.xsd
+++ b/src/Symfony/Bundle/FrameworkBundle/Resources/config/schema/symfony-1.0.xsd
@@ -176,6 +176,7 @@
             <xsd:element name="path" type="xsd:string" minOccurs="0" maxOccurs="unbounded" />
             <xsd:element name="enabled-locale" type="xsd:string" minOccurs="0" maxOccurs="unbounded" />
             <xsd:element name="pseudo-localization" type="pseudo_localization" minOccurs="0" maxOccurs="1" />
+            <xsd:element name="provider" type="translation_provider" minOccurs="0" maxOccurs="unbounded" />
         </xsd:sequence>
         <xsd:attribute name="enabled" type="xsd:boolean" />
         <xsd:attribute name="fallback" type="xsd:string" />
@@ -195,6 +196,15 @@
         <xsd:attribute name="parse_html" type="xsd:boolean" />
     </xsd:complexType>
 
+    <xsd:complexType name="translation_provider">
+        <xsd:sequence>
+            <xsd:element name="domain" type="xsd:string" minOccurs="0" maxOccurs="unbounded" />
+            <xsd:element name="locale" type="xsd:string" minOccurs="0" maxOccurs="unbounded" />
+        </xsd:sequence>
+        <xsd:attribute name="name" type="xsd:string" />
+        <xsd:attribute name="dsn" type="xsd:string" />
+    </xsd:complexType>
+
     <xsd:complexType name="validation">
         <xsd:choice minOccurs="0" maxOccurs="unbounded">
             <xsd:element name="static-method" type="xsd:string" />
diff --git a/src/Symfony/Bundle/FrameworkBundle/Resources/config/translation_providers.php b/src/Symfony/Bundle/FrameworkBundle/Resources/config/translation_providers.php
new file mode 100644
index 0000000000..ffc70033fc
--- /dev/null
+++ b/src/Symfony/Bundle/FrameworkBundle/Resources/config/translation_providers.php
@@ -0,0 +1,45 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\DependencyInjection\Loader\Configurator;
+
+use Symfony\Component\Translation\Bridge\Loco\Provider\LocoProviderFactory;
+use Symfony\Component\Translation\Provider\NullProviderFactory;
+use Symfony\Component\Translation\Provider\TranslationProviderCollection;
+use Symfony\Component\Translation\Provider\TranslationProviderCollectionFactory;
+
+return static function (ContainerConfigurator $container) {
+    $container->services()
+        ->set('translation.provider_collection', TranslationProviderCollection::class)
+            ->factory([service('translation.provider_collection_factory'), 'fromConfig'])
+            ->args([
+                [], // Providers
+            ])
+
+        ->set('translation.provider_collection_factory', TranslationProviderCollectionFactory::class)
+            ->args([
+                tagged_iterator('translation.provider_factory'),
+                [], // Enabled locales
+            ])
+
+        ->set('translation.provider_factory.null', NullProviderFactory::class)
+            ->tag('translation.provider_factory')
+
+        ->set('translation.provider_factory.loco', LocoProviderFactory::class)
+            ->args([
+                service('http_client'),
+                service('logger'),
+                param('kernel.default_locale'),
+                service('translation.loader.xliff'),
+            ])
+            ->tag('translation.provider_factory')
+    ;
+};
diff --git a/src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/ConfigurationTest.php b/src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/ConfigurationTest.php
index efa0acf856..b056ed498e 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/ConfigurationTest.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/ConfigurationTest.php
@@ -418,6 +418,7 @@ class ConfigurationTest extends TestCase
                     'parse_html' => false,
                     'localizable_html_attributes' => [],
                 ],
+                'providers' => [],
             ],
             'validation' => [
                 'enabled' => !class_exists(FullStack::class),
diff --git a/src/Symfony/Component/Translation/Bridge/Loco/.gitattributes b/src/Symfony/Component/Translation/Bridge/Loco/.gitattributes
new file mode 100644
index 0000000000..84c7add058
--- /dev/null
+++ b/src/Symfony/Component/Translation/Bridge/Loco/.gitattributes
@@ -0,0 +1,4 @@
+/Tests export-ignore
+/phpunit.xml.dist export-ignore
+/.gitattributes export-ignore
+/.gitignore export-ignore
diff --git a/src/Symfony/Component/Translation/Bridge/Loco/.gitignore b/src/Symfony/Component/Translation/Bridge/Loco/.gitignore
new file mode 100644
index 0000000000..76367ee5bb
--- /dev/null
+++ b/src/Symfony/Component/Translation/Bridge/Loco/.gitignore
@@ -0,0 +1,4 @@
+vendor/
+composer.lock
+phpunit.xml
+.phpunit.result.cache
diff --git a/src/Symfony/Component/Translation/Bridge/Loco/CHANGELOG.md b/src/Symfony/Component/Translation/Bridge/Loco/CHANGELOG.md
new file mode 100644
index 0000000000..bbb9efcaeb
--- /dev/null
+++ b/src/Symfony/Component/Translation/Bridge/Loco/CHANGELOG.md
@@ -0,0 +1,7 @@
+CHANGELOG
+=========
+
+5.3
+---
+
+ * Create the bridge
diff --git a/src/Symfony/Component/Translation/Bridge/Loco/LICENSE b/src/Symfony/Component/Translation/Bridge/Loco/LICENSE
new file mode 100644
index 0000000000..efb17f98e7
--- /dev/null
+++ b/src/Symfony/Component/Translation/Bridge/Loco/LICENSE
@@ -0,0 +1,19 @@
+Copyright (c) 2021 Fabien Potencier
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is furnished
+to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
diff --git a/src/Symfony/Component/Translation/Bridge/Loco/Provider/LocoProvider.php b/src/Symfony/Component/Translation/Bridge/Loco/Provider/LocoProvider.php
new file mode 100644
index 0000000000..8b315cbd76
--- /dev/null
+++ b/src/Symfony/Component/Translation/Bridge/Loco/Provider/LocoProvider.php
@@ -0,0 +1,245 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Translation\Bridge\Loco\Provider;
+
+use Psr\Log\LoggerInterface;
+use Symfony\Component\Translation\Exception\ProviderException;
+use Symfony\Component\Translation\Loader\LoaderInterface;
+use Symfony\Component\Translation\Provider\ProviderInterface;
+use Symfony\Component\Translation\TranslatorBag;
+use Symfony\Component\Translation\TranslatorBagInterface;
+use Symfony\Contracts\HttpClient\HttpClientInterface;
+
+/**
+ * @author Mathieu Santostefano <msantostefano@protonmail.com>
+ *
+ * In Loco:
+ *  * Tags refers to Symfony's translation domains
+ *  * Assets refers to Symfony's translation keys
+ *  * Translations refers to Symfony's translated messages
+ *
+ * @experimental in 5.3
+ */
+final class LocoProvider implements ProviderInterface
+{
+    private $client;
+    private $loader;
+    private $logger;
+    private $defaultLocale;
+    private $endpoint;
+
+    public function __construct(HttpClientInterface $client, LoaderInterface $loader, LoggerInterface $logger, string $defaultLocale, string $endpoint)
+    {
+        $this->client = $client;
+        $this->loader = $loader;
+        $this->logger = $logger;
+        $this->defaultLocale = $defaultLocale;
+        $this->endpoint = $endpoint;
+    }
+
+    public function __toString(): string
+    {
+        return sprintf('%s://%s', LocoProviderFactory::SCHEME, $this->endpoint);
+    }
+
+    public function write(TranslatorBagInterface $translatorBag): void
+    {
+        $catalogue = $translatorBag->getCatalogue($this->defaultLocale);
+
+        if (!$catalogue) {
+            $catalogue = $translatorBag->getCatalogues()[0];
+        }
+
+        // Create keys on Loco
+        foreach ($catalogue->all() as $domain => $messages) {
+            $ids = [];
+            foreach ($messages as $id => $message) {
+                $ids[] = $id;
+                $this->createAsset($id);
+            }
+            if ($ids) {
+                $this->tagsAssets($ids, $domain);
+            }
+        }
+
+        // Push translations in all locales and tag them with domain
+        foreach ($translatorBag->getCatalogues() as $catalogue) {
+            $locale = $catalogue->getLocale();
+
+            if (!\in_array($locale, $this->getLocales())) {
+                $this->createLocale($locale);
+            }
+
+            foreach ($catalogue->all() as $messages) {
+                foreach ($messages as $id => $message) {
+                    $this->translateAsset($id, $message, $locale);
+                }
+            }
+        }
+    }
+
+    public function read(array $domains, array $locales): TranslatorBag
+    {
+        $domains = $domains ?: ['*'];
+        $translatorBag = new TranslatorBag();
+
+        foreach ($locales as $locale) {
+            foreach ($domains as $domain) {
+                $response = $this->client->request('GET', sprintf('export/locale/%s.xlf?filter=%s&status=translated', $locale, $domain));
+
+                if (404 === $response->getStatusCode()) {
+                    $this->logger->error(sprintf('Locale "%s" for domain "%s" does not exist in Loco.', $locale, $domain));
+                    continue;
+                }
+
+                $responseContent = $response->getContent(false);
+
+                if (200 !== $response->getStatusCode()) {
+                    throw new ProviderException('Unable to read the Loco response: '.$responseContent, $response);
+                }
+
+                $translatorBag->addCatalogue($this->loader->load($responseContent, $locale, $domain));
+            }
+        }
+
+        return $translatorBag;
+    }
+
+    public function delete(TranslatorBagInterface $translatorBag): void
+    {
+        $deletedIds = [];
+
+        foreach ($translatorBag->getCatalogues() as $catalogue) {
+            foreach ($catalogue->all() as $messages) {
+                foreach ($messages as $id => $message) {
+                    if (\in_array($id, $deletedIds, true)) {
+                        continue;
+                    }
+
+                    $this->deleteAsset($id);
+                    $deletedIds[] = $id;
+                }
+            }
+        }
+    }
+
+    private function createAsset(string $id): void
+    {
+        $response = $this->client->request('POST', 'assets', [
+            'body' => [
+                'name' => $id,
+                'id' => $id,
+                'type' => 'text',
+                'default' => 'untranslated',
+            ],
+        ]);
+
+        if (409 === $response->getStatusCode()) {
+            $this->logger->info(sprintf('Translation key "%s" already exists in Loco.', $id), [
+                'id' => $id,
+            ]);
+        } elseif (201 !== $response->getStatusCode()) {
+            $this->logger->error(sprintf('Unable to add new translation key "%s" to Loco: (status code: "%s") "%s".', $id, $response->getStatusCode(), $response->getContent(false)));
+        }
+    }
+
+    private function translateAsset(string $id, string $message, string $locale): void
+    {
+        $response = $this->client->request('POST', sprintf('translations/%s/%s', $id, $locale), [
+            'body' => $message,
+        ]);
+
+        if (200 !== $response->getStatusCode()) {
+            $this->logger->error(sprintf('Unable to add translation message "%s" (for key: "%s" in locale "%s") to Loco: "%s".', $message, $id, $locale, $response->getContent(false)));
+        }
+    }
+
+    private function tagsAssets(array $ids, string $tag): void
+    {
+        $idsAsString = implode(',', array_unique($ids));
+
+        if (!\in_array($tag, $this->getTags(), true)) {
+            $this->createTag($tag);
+        }
+
+        $response = $this->client->request('POST', sprintf('tags/%s.json', $tag), [
+            'body' => $idsAsString,
+        ]);
+
+        if (200 !== $response->getStatusCode()) {
+            $this->logger->error(sprintf('Unable to add tag "%s" on translation keys "%s" to Loco: "%s".', $tag, $idsAsString, $response->getContent(false)));
+        }
+    }
+
+    private function createTag(string $tag): void
+    {
+        $response = $this->client->request('POST', 'tags.json', [
+            'body' => [
+                'name' => $tag,
+            ],
+        ]);
+
+        if (201 !== $response->getStatusCode()) {
+            $this->logger->error(sprintf('Unable to create tag "%s" on Loco: "%s".', $tag, $response->getContent(false)));
+        }
+    }
+
+    private function getTags(): array
+    {
+        $response = $this->client->request('GET', 'tags.json');
+        $content = $response->toArray(false);
+
+        if (200 !== $response->getStatusCode()) {
+            throw new ProviderException(sprintf('Unable to get tags on Loco: "%s".', $response->getContent(false)), $response);
+        }
+
+        return $content ?: [];
+    }
+
+    private function createLocale(string $locale): void
+    {
+        $response = $this->client->request('POST', 'locales', [
+            'body' => [
+                'code' => $locale,
+            ],
+        ]);
+
+        if (201 !== $response->getStatusCode()) {
+            $this->logger->error(sprintf('Unable to create locale "%s" on Loco: "%s".', $locale, $response->getContent(false)));
+        }
+    }
+
+    private function getLocales(): array
+    {
+        $response = $this->client->request('GET', 'locales');
+        $content = $response->toArray(false);
+
+        if (200 !== $response->getStatusCode()) {
+            throw new ProviderException(sprintf('Unable to get locales on Loco: "%s".', $response->getContent(false)), $response);
+        }
+
+        return array_reduce($content, function ($carry, $locale) {
+            $carry[] = $locale['code'];
+
+            return $carry;
+        }, []);
+    }
+
+    private function deleteAsset(string $id): void
+    {
+        $response = $this->client->request('DELETE', sprintf('assets/%s.json', $id));
+
+        if (200 !== $response->getStatusCode()) {
+            $this->logger->error(sprintf('Unable to delete translation key "%s" to Loco: "%s".', $id, $response->getContent(false)));
+        }
+    }
+}
diff --git a/src/Symfony/Component/Translation/Bridge/Loco/Provider/LocoProviderFactory.php b/src/Symfony/Component/Translation/Bridge/Loco/Provider/LocoProviderFactory.php
new file mode 100644
index 0000000000..06cb0c71cc
--- /dev/null
+++ b/src/Symfony/Component/Translation/Bridge/Loco/Provider/LocoProviderFactory.php
@@ -0,0 +1,69 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Translation\Bridge\Loco\Provider;
+
+use Psr\Log\LoggerInterface;
+use Symfony\Component\Translation\Exception\UnsupportedSchemeException;
+use Symfony\Component\Translation\Loader\LoaderInterface;
+use Symfony\Component\Translation\Provider\AbstractProviderFactory;
+use Symfony\Component\Translation\Provider\Dsn;
+use Symfony\Component\Translation\Provider\ProviderInterface;
+use Symfony\Contracts\HttpClient\HttpClientInterface;
+
+/**
+ * @author Mathieu Santostefano <msantostefano@protonmail.com>
+ *
+ * @experimental in 5.3
+ */
+final class LocoProviderFactory extends AbstractProviderFactory
+{
+    public const SCHEME = 'loco';
+    private const HOST = 'localise.biz/api/';
+
+    private $client;
+    private $logger;
+    private $defaultLocale;
+    private $loader;
+
+    public function __construct(HttpClientInterface $client, LoggerInterface $logger, string $defaultLocale, LoaderInterface $loader)
+    {
+        $this->client = $client;
+        $this->logger = $logger;
+        $this->defaultLocale = $defaultLocale;
+        $this->loader = $loader;
+    }
+
+    /**
+     * @return LocoProvider
+     */
+    public function create(Dsn $dsn): ProviderInterface
+    {
+        if (self::SCHEME !== $dsn->getScheme()) {
+            throw new UnsupportedSchemeException($dsn, self::SCHEME, $this->getSupportedSchemes());
+        }
+
+        $endpoint = sprintf('%s%s', 'default' === $dsn->getHost() ? self::HOST : $dsn->getHost(), $dsn->getPort() ? ':'.$dsn->getPort() : '');
+        $client = $this->client->withOptions([
+            'base_uri' => 'https://'.$endpoint,
+            'headers' => [
+                'Authorization' => 'Loco '.$this->getUser($dsn),
+            ],
+        ]);
+
+        return new LocoProvider($client, $this->loader, $this->logger, $this->defaultLocale, $endpoint);
+    }
+
+    protected function getSupportedSchemes(): array
+    {
+        return [self::SCHEME];
+    }
+}
diff --git a/src/Symfony/Component/Translation/Bridge/Loco/README.md b/src/Symfony/Component/Translation/Bridge/Loco/README.md
new file mode 100644
index 0000000000..2624f3329d
--- /dev/null
+++ b/src/Symfony/Component/Translation/Bridge/Loco/README.md
@@ -0,0 +1,25 @@
+Loco Translation Provider
+=========================
+
+Provides Loco integration for Symfony Translation.
+
+DSN example
+-----------
+
+```
+// .env file
+LOCO_DSN=loco://API_KEY@default
+```
+
+where:
+ - `API_KEY` is your Loco project API key
+
+[more information on Loco website](https://localise.biz/help/developers/api-keys)
+
+Resources
+---------
+
+  * [Contributing](https://symfony.com/doc/current/contributing/index.html)
+  * [Report issues](https://github.com/symfony/symfony/issues) and
+    [send Pull Requests](https://github.com/symfony/symfony/pulls)
+    in the [main Symfony repository](https://github.com/symfony/symfony)
diff --git a/src/Symfony/Component/Translation/Bridge/Loco/Tests/LocoProviderFactoryTest.php b/src/Symfony/Component/Translation/Bridge/Loco/Tests/LocoProviderFactoryTest.php
new file mode 100644
index 0000000000..f108a58da7
--- /dev/null
+++ b/src/Symfony/Component/Translation/Bridge/Loco/Tests/LocoProviderFactoryTest.php
@@ -0,0 +1,39 @@
+<?php
+
+namespace Symfony\Component\Translation\Bridge\Loco\Tests;
+
+use Symfony\Component\Translation\Bridge\Loco\Provider\LocoProviderFactory;
+use Symfony\Component\Translation\Provider\ProviderFactoryInterface;
+use Symfony\Component\Translation\Tests\ProviderFactoryTestCase;
+
+class LocoProviderFactoryTest extends ProviderFactoryTestCase
+{
+    public function supportsProvider(): iterable
+    {
+        yield [true, 'loco://API_KEY@default'];
+        yield [false, 'somethingElse://API_KEY@default'];
+    }
+
+    public function unsupportedSchemeProvider(): iterable
+    {
+        yield ['somethingElse://API_KEY@default'];
+    }
+
+    public function createProvider(): iterable
+    {
+        yield [
+            'loco://localise.biz/api/',
+            'loco://API_KEY@default',
+        ];
+    }
+
+    public function incompleteDsnProvider(): iterable
+    {
+        yield ['loco://default'];
+    }
+
+    public function createFactory(): ProviderFactoryInterface
+    {
+        return new LocoProviderFactory($this->getClient(), $this->getLogger(), $this->getDefaultLocale(), $this->getLoader());
+    }
+}
diff --git a/src/Symfony/Component/Translation/Bridge/Loco/Tests/LocoProviderTest.php b/src/Symfony/Component/Translation/Bridge/Loco/Tests/LocoProviderTest.php
new file mode 100644
index 0000000000..5ea577fb67
--- /dev/null
+++ b/src/Symfony/Component/Translation/Bridge/Loco/Tests/LocoProviderTest.php
@@ -0,0 +1,516 @@
+<?php
+
+namespace Symfony\Component\Translation\Bridge\Loco\Tests;
+
+use Psr\Log\LoggerInterface;
+use Symfony\Component\HttpClient\MockHttpClient;
+use Symfony\Component\Translation\Bridge\Loco\Provider\LocoProvider;
+use Symfony\Component\Translation\Loader\ArrayLoader;
+use Symfony\Component\Translation\Loader\LoaderInterface;
+use Symfony\Component\Translation\Loader\XliffFileLoader;
+use Symfony\Component\Translation\MessageCatalogue;
+use Symfony\Component\Translation\Provider\ProviderInterface;
+use Symfony\Component\Translation\Tests\ProviderTestCase;
+use Symfony\Component\Translation\TranslatorBag;
+use Symfony\Contracts\HttpClient\HttpClientInterface;
+use Symfony\Contracts\HttpClient\ResponseInterface;
+
+class LocoProviderTest extends ProviderTestCase
+{
+    public function createProvider(HttpClientInterface $client, LoaderInterface $loader, LoggerInterface $logger, string $defaultLocale, string $endpoint): ProviderInterface
+    {
+        return new LocoProvider($client, $loader, $logger, $defaultLocale, $endpoint);
+    }
+
+    public function testCompleteWriteProcess()
+    {
+        $createAssetResponse = $this->createMock(ResponseInterface::class);
+        $createAssetResponse->expects($this->exactly(4))
+            ->method('getStatusCode')
+            ->willReturn(201);
+
+        $getLocalesResponse = $this->createMock(ResponseInterface::class);
+        $getLocalesResponse->expects($this->exactly(4))
+            ->method('getStatusCode')
+            ->willReturn(200);
+        $getLocalesResponse->expects($this->exactly(2))
+            ->method('getContent')
+            ->with(false)
+            ->willReturn('[{"code":"en"}]');
+
+        $createLocaleResponse = $this->createMock(ResponseInterface::class);
+        $createLocaleResponse->expects($this->exactly(2))
+            ->method('getStatusCode')
+            ->willReturn(201);
+
+        $translateAssetResponse = $this->createMock(ResponseInterface::class);
+        $translateAssetResponse->expects($this->exactly(8))
+            ->method('getStatusCode')
+            ->willReturn(200);
+
+        $getTagsEmptyResponse = $this->createMock(ResponseInterface::class);
+        $getTagsEmptyResponse->expects($this->exactly(2))
+            ->method('getStatusCode')
+            ->willReturn(200);
+        $getTagsEmptyResponse->expects($this->once())
+            ->method('getContent')
+            ->with(false)
+            ->willReturn('[]');
+
+        $getTagsNotEmptyResponse = $this->createMock(ResponseInterface::class);
+        $getTagsNotEmptyResponse->expects($this->exactly(2))
+            ->method('getStatusCode')
+            ->willReturn(200);
+        $getTagsNotEmptyResponse->expects($this->once())
+            ->method('getContent')
+            ->with(false)
+            ->willReturn('["messages"]');
+
+        $createTagResponse = $this->createMock(ResponseInterface::class);
+        $createTagResponse->expects($this->exactly(4))
+            ->method('getStatusCode')
+            ->willReturn(201);
+
+        $tagAssetResponse = $this->createMock(ResponseInterface::class);
+        $tagAssetResponse->expects($this->exactly(4))
+            ->method('getStatusCode')
+            ->willReturn(200);
+
+        $expectedAuthHeader = 'Authorization: Loco API_KEY';
+
+        $responses = [
+            'createAsset1' => function (string $method, string $url, array $options = []) use ($createAssetResponse, $expectedAuthHeader): ResponseInterface {
+                $expectedBody = http_build_query([
+                    'name' => 'a',
+                    'id' => 'a',
+                    'type' => 'text',
+                    'default' => 'untranslated',
+                ]);
+
+                $this->assertEquals('POST', $method);
+                $this->assertEquals($expectedAuthHeader, $options['normalized_headers']['authorization'][0]);
+                $this->assertEquals($expectedBody, $options['body']);
+
+                return $createAssetResponse;
+            },
+            'getTags1' => function (string $method, string $url, array $options = []) use ($getTagsEmptyResponse, $expectedAuthHeader): ResponseInterface {
+                $this->assertEquals('GET', $method);
+                $this->assertEquals('https://localise.biz/api/tags.json', $url);
+                $this->assertEquals($expectedAuthHeader, $options['normalized_headers']['authorization'][0]);
+
+                return $getTagsEmptyResponse;
+            },
+            'createTag1' => function (string $method, string $url, array $options = []) use ($createTagResponse, $expectedAuthHeader): ResponseInterface {
+                $this->assertEquals('POST', $method);
+                $this->assertEquals('https://localise.biz/api/tags.json', $url);
+                $this->assertEquals($expectedAuthHeader, $options['normalized_headers']['authorization'][0]);
+                $this->assertEquals(http_build_query(['name' => 'messages']), $options['body']);
+
+                return $createTagResponse;
+            },
+            'tagAsset1' => function (string $method, string $url, array $options = []) use ($tagAssetResponse, $expectedAuthHeader): ResponseInterface {
+                $this->assertEquals('POST', $method);
+                $this->assertEquals('https://localise.biz/api/tags/messages.json', $url);
+                $this->assertEquals($expectedAuthHeader, $options['normalized_headers']['authorization'][0]);
+                $this->assertEquals('a', $options['body']);
+
+                return $tagAssetResponse;
+            },
+            'createAsset2' => function (string $method, string $url, array $options = []) use ($createAssetResponse, $expectedAuthHeader): ResponseInterface {
+                $expectedBody = http_build_query([
+                    'name' => 'post.num_comments',
+                    'id' => 'post.num_comments',
+                    'type' => 'text',
+                    'default' => 'untranslated',
+                ]);
+
+                $this->assertEquals('POST', $method);
+                $this->assertEquals($expectedAuthHeader, $options['normalized_headers']['authorization'][0]);
+                $this->assertEquals($expectedBody, $options['body']);
+
+                return $createAssetResponse;
+            },
+            'getTags2' => function (string $method, string $url, array $options = []) use ($getTagsNotEmptyResponse, $expectedAuthHeader): ResponseInterface {
+                $this->assertEquals('GET', $method);
+                $this->assertEquals('https://localise.biz/api/tags.json', $url);
+                $this->assertEquals($expectedAuthHeader, $options['normalized_headers']['authorization'][0]);
+
+                return $getTagsNotEmptyResponse;
+            },
+            'createTag2' => function (string $method, string $url, array $options = []) use ($createTagResponse, $expectedAuthHeader): ResponseInterface {
+                $this->assertEquals('POST', $method);
+                $this->assertEquals('https://localise.biz/api/tags.json', $url);
+                $this->assertEquals($expectedAuthHeader, $options['normalized_headers']['authorization'][0]);
+                $this->assertEquals(http_build_query(['name' => 'validators']), $options['body']);
+
+                return $createTagResponse;
+            },
+            'tagAsset2' => function (string $method, string $url, array $options = []) use ($tagAssetResponse, $expectedAuthHeader): ResponseInterface {
+                $this->assertEquals('POST', $method);
+                $this->assertEquals('https://localise.biz/api/tags/validators.json', $url);
+                $this->assertEquals($expectedAuthHeader, $options['normalized_headers']['authorization'][0]);
+                $this->assertEquals('post.num_comments', $options['body']);
+
+                return $tagAssetResponse;
+            },
+
+            'getLocales1' => function (string $method, string $url, array $options = []) use ($getLocalesResponse, $expectedAuthHeader): ResponseInterface {
+                $this->assertEquals('GET', $method);
+                $this->assertEquals('https://localise.biz/api/locales', $url);
+                $this->assertEquals($expectedAuthHeader, $options['normalized_headers']['authorization'][0]);
+
+                return $getLocalesResponse;
+            },
+
+            'translateAsset1' => function (string $method, string $url, array $options = []) use ($translateAssetResponse, $expectedAuthHeader): ResponseInterface {
+                $this->assertEquals('POST', $method);
+                $this->assertEquals('https://localise.biz/api/translations/a/en', $url);
+                $this->assertEquals($expectedAuthHeader, $options['normalized_headers']['authorization'][0]);
+                $this->assertEquals('trans_en_a', $options['body']);
+
+                return $translateAssetResponse;
+            },
+            'translateAsset2' => function (string $method, string $url, array $options = []) use ($translateAssetResponse, $expectedAuthHeader): ResponseInterface {
+                $this->assertEquals('POST', $method);
+                $this->assertEquals('https://localise.biz/api/translations/post.num_comments/en', $url);
+                $this->assertEquals($expectedAuthHeader, $options['normalized_headers']['authorization'][0]);
+                $this->assertEquals('{count, plural, one {# comment} other {# comments}}', $options['body']);
+
+                return $translateAssetResponse;
+            },
+
+            'getLocales2' => function (string $method, string $url, array $options = []) use ($getLocalesResponse, $expectedAuthHeader): ResponseInterface {
+                $this->assertEquals('GET', $method);
+                $this->assertEquals('https://localise.biz/api/locales', $url);
+                $this->assertEquals($expectedAuthHeader, $options['normalized_headers']['authorization'][0]);
+
+                return $getLocalesResponse;
+            },
+
+            'createLocale1' => function (string $method, string $url, array $options = []) use ($createLocaleResponse, $expectedAuthHeader): ResponseInterface {
+                $this->assertEquals('POST', $method);
+                $this->assertEquals('https://localise.biz/api/locales', $url);
+                $this->assertEquals($expectedAuthHeader, $options['normalized_headers']['authorization'][0]);
+                $this->assertEquals('code=fr', $options['body']);
+
+                return $createLocaleResponse;
+            },
+
+            'translateAsset3' => function (string $method, string $url, array $options = []) use ($translateAssetResponse, $expectedAuthHeader): ResponseInterface {
+                $this->assertEquals('POST', $method);
+                $this->assertEquals('https://localise.biz/api/translations/a/fr', $url);
+                $this->assertEquals($expectedAuthHeader, $options['normalized_headers']['authorization'][0]);
+                $this->assertEquals('trans_fr_a', $options['body']);
+
+                return $translateAssetResponse;
+            },
+            'translateAsset4' => function (string $method, string $url, array $options = []) use ($translateAssetResponse, $expectedAuthHeader): ResponseInterface {
+                $this->assertEquals('POST', $method);
+                $this->assertEquals('https://localise.biz/api/translations/post.num_comments/fr', $url);
+                $this->assertEquals($expectedAuthHeader, $options['normalized_headers']['authorization'][0]);
+                $this->assertEquals('{count, plural, one {# commentaire} other {# commentaires}}', $options['body']);
+
+                return $translateAssetResponse;
+            },
+        ];
+
+        $translatorBag = new TranslatorBag();
+        $translatorBag->addCatalogue(new MessageCatalogue('en', [
+            'messages' => ['a' => 'trans_en_a'],
+            'validators' => ['post.num_comments' => '{count, plural, one {# comment} other {# comments}}'],
+        ]));
+        $translatorBag->addCatalogue(new MessageCatalogue('fr', [
+            'messages' => ['a' => 'trans_fr_a'],
+            'validators' => ['post.num_comments' => '{count, plural, one {# commentaire} other {# commentaires}}'],
+        ]));
+
+        $provider = $this->createProvider((new MockHttpClient($responses))->withOptions([
+            'base_uri' => 'https://localise.biz/api/',
+            'headers' => [
+                'Authorization' => 'Loco API_KEY',
+            ],
+        ]), $this->getLoader(), $this->getLogger(), $this->getDefaultLocale(), 'localise.biz/api/');
+        $provider->write($translatorBag);
+    }
+
+    /**
+     * @dataProvider getLocoResponsesForOneLocaleAndOneDomain
+     */
+    public function testReadForOneLocaleAndOneDomain(string $locale, string $domain, string $responseContent, TranslatorBag $expectedTranslatorBag)
+    {
+        $response = $this->createMock(ResponseInterface::class);
+        $response->expects($this->once())
+            ->method('getContent')
+            ->willReturn($responseContent);
+        $response->expects($this->exactly(2))
+            ->method('getStatusCode')
+            ->willReturn(200);
+
+        $loader = $this->getLoader();
+        $loader->expects($this->once())
+            ->method('load')
+            ->willReturn($expectedTranslatorBag->getCatalogue($locale));
+
+        $locoProvider = $this->createProvider((new MockHttpClient($response))->withOptions([
+            'base_uri' => 'https://localise.biz/api/',
+            'headers' => [
+                'Authorization' => 'Loco API_KEY',
+            ],
+        ]), $loader, $this->getLogger(), $this->getDefaultLocale(), 'localise.biz/api/');
+        $translatorBag = $locoProvider->read([$domain], [$locale]);
+
+        $this->assertEquals($expectedTranslatorBag->getCatalogues(), $translatorBag->getCatalogues());
+    }
+
+    /**
+     * @dataProvider getLocoResponsesForManyLocalesAndManyDomains
+     */
+    public function testReadForManyLocalesAndManyDomains(array $locales, array $domains, array $responseContents, array $expectedTranslatorBags)
+    {
+        foreach ($locales as $locale) {
+            foreach ($domains as $domain) {
+                $response = $this->createMock(ResponseInterface::class);
+                $response->expects($this->once())
+                    ->method('getContent')
+                    ->willReturn($responseContents[$domain][$locale]);
+                $response->expects($this->exactly(2))
+                    ->method('getStatusCode')
+                    ->willReturn(200);
+
+                $locoProvider = new LocoProvider((new MockHttpClient($response))->withOptions([
+                    'base_uri' => 'https://localise.biz/api/',
+                    'headers' => [
+                        'Authorization' => 'Loco API_KEY',
+                    ],
+                ]), new XliffFileLoader(), $this->getLogger(), $this->getDefaultLocale(), 'localise.biz/api/');
+                $translatorBag = $locoProvider->read([$domain], [$locale]);
+                // We don't want to assert equality of metadata here, due to the ArrayLoader usage.
+                $translatorBag->getCatalogue($locale)->deleteMetadata('foo', '');
+
+                $this->assertEquals($expectedTranslatorBags[$domain]->getCatalogue($locale), $translatorBag->getCatalogue($locale));
+            }
+        }
+    }
+
+    public function toStringProvider(): iterable
+    {
+        yield [
+            new LocoProvider($this->getClient()->withOptions([
+                'base_uri' => 'https://localise.biz/api/',
+                'headers' => [
+                    'Authorization' => 'Loco API_KEY',
+                ],
+            ]), $this->getLoader(), $this->getLogger(), $this->getDefaultLocale(), 'localise.biz/api/'),
+            'loco://localise.biz/api/',
+        ];
+
+        yield [
+            new LocoProvider($this->getClient()->withOptions([
+                'base_uri' => 'https://example.com',
+                'headers' => [
+                    'Authorization' => 'Loco API_KEY',
+                ],
+            ]), $this->getLoader(), $this->getLogger(), $this->getDefaultLocale(), 'example.com'),
+            'loco://example.com',
+        ];
+
+        yield [
+            new LocoProvider($this->getClient()->withOptions([
+                'base_uri' => 'https://example.com:99',
+                'headers' => [
+                    'Authorization' => 'Loco API_KEY',
+                ],
+            ]), $this->getLoader(), $this->getLogger(), $this->getDefaultLocale(), 'example.com:99'),
+            'loco://example.com:99',
+        ];
+    }
+
+    public function getLocoResponsesForOneLocaleAndOneDomain(): \Generator
+    {
+        $arrayLoader = new ArrayLoader();
+
+        $expectedTranslatorBagEn = new TranslatorBag();
+        $expectedTranslatorBagEn->addCatalogue($arrayLoader->load([
+            'index.hello' => 'Hello',
+            'index.greetings' => 'Welcome, {firstname}!',
+        ], 'en', 'messages'));
+
+        yield ['en', 'messages', <<<'XLIFF'
+<?xml version="1.0" encoding="UTF-8"?>
+<xliff xmlns="urn:oasis:names:tc:xliff:document:1.2" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="1.2" xsi:schemaLocation="urn:oasis:names:tc:xliff:document:1.2 http://docs.oasis-open.org/xliff/v1.2/os/xliff-core-1.2-strict.xsd">
+  <file original="https://localise.biz/user/symfony-translation-provider" source-language="en" datatype="database" tool-id="loco">
+    <header>
+      <tool tool-id="loco" tool-name="Loco" tool-version="1.0.25 20201211-1" tool-company="Loco"/>
+    </header>
+    <body>
+      <trans-unit id="loco:5fd89b853ee27904dd6c5f67" resname="index.hello" datatype="plaintext">
+        <source>index.hello</source>
+        <target state="translated">Hello</target>
+      </trans-unit>
+      <trans-unit id="loco:5fd89b8542e5aa5cc27457e2" resname="index.greetings" datatype="plaintext" extradata="loco:format=icu">
+        <source>index.greetings</source>
+        <target state="translated">Welcome, {firstname}!</target>
+      </trans-unit>
+    </body>
+  </file>
+</xliff>
+XLIFF
+            ,
+            $expectedTranslatorBagEn,
+        ];
+
+        $expectedTranslatorBagFr = new TranslatorBag();
+        $expectedTranslatorBagFr->addCatalogue($arrayLoader->load([
+            'index.hello' => 'Bonjour',
+            'index.greetings' => 'Bienvenue, {firstname} !',
+        ], 'fr', 'messages'));
+
+        yield ['fr', 'messages', <<<'XLIFF'
+<?xml version="1.0" encoding="UTF-8"?>
+<xliff xmlns="urn:oasis:names:tc:xliff:document:1.2" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="1.2" xsi:schemaLocation="urn:oasis:names:tc:xliff:document:1.2 http://docs.oasis-open.org/xliff/v1.2/os/xliff-core-1.2-strict.xsd">
+  <file original="https://localise.biz/user/symfony-translation-provider" source-language="en" datatype="database" tool-id="loco">
+    <header>
+      <tool tool-id="loco" tool-name="Loco" tool-version="1.0.25 20201211-1" tool-company="Loco"/>
+    </header>
+    <body>
+      <trans-unit id="loco:5fd89b853ee27904dd6c5f67" resname="index.hello" datatype="plaintext">
+        <source>index.hello</source>
+        <target state="translated">Bonjour</target>
+      </trans-unit>
+      <trans-unit id="loco:5fd89b8542e5aa5cc27457e2" resname="index.greetings" datatype="plaintext" extradata="loco:format=icu">
+        <source>index.greetings</source>
+        <target state="translated">Bienvenue, {firstname} !</target>
+      </trans-unit>
+    </body>
+  </file>
+</xliff>
+XLIFF
+            ,
+            $expectedTranslatorBagFr,
+        ];
+    }
+
+    public function getLocoResponsesForManyLocalesAndManyDomains(): \Generator
+    {
+        $arrayLoader = new ArrayLoader();
+
+        $expectedTranslatorBagMessages = new TranslatorBag();
+        $expectedTranslatorBagMessages->addCatalogue($arrayLoader->load([
+            'index.hello' => 'Hello',
+            'index.greetings' => 'Welcome, {firstname}!',
+        ], 'en', 'messages'));
+        $expectedTranslatorBagMessages->addCatalogue($arrayLoader->load([
+            'index.hello' => 'Bonjour',
+            'index.greetings' => 'Bienvenue, {firstname} !',
+        ], 'fr', 'messages'));
+
+        $expectedTranslatorBagValidators = new TranslatorBag();
+        $expectedTranslatorBagValidators->addCatalogue($arrayLoader->load([
+            'firstname.error' => 'Firstname must contains only letters.',
+            'lastname.error' => 'Lastname must contains only letters.',
+        ], 'en', 'validators'));
+        $expectedTranslatorBagValidators->addCatalogue($arrayLoader->load([
+            'firstname.error' => 'Le prénom ne peut contenir que des lettres.',
+            'lastname.error' => 'Le nom de famille ne peut contenir que des lettres.',
+        ], 'fr', 'validators'));
+
+        yield [
+            ['en', 'fr'],
+            ['messages', 'validators'],
+            [
+                'messages' => [
+                    'en' => <<<'XLIFF'
+<?xml version="1.0" encoding="UTF-8"?>
+<xliff xmlns="urn:oasis:names:tc:xliff:document:1.2" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="1.2" xsi:schemaLocation="urn:oasis:names:tc:xliff:document:1.2 http://docs.oasis-open.org/xliff/v1.2/os/xliff-core-1.2-strict.xsd">
+  <file original="https://localise.biz/user/symfony-translation-provider" source-language="en" datatype="database" tool-id="loco">
+    <header>
+      <tool tool-id="loco" tool-name="Loco" tool-version="1.0.25 20201211-1" tool-company="Loco"/>
+    </header>
+    <body>
+      <trans-unit id="loco:5fd89b853ee27904dd6c5f67" resname="index.hello" datatype="plaintext">
+        <source>index.hello</source>
+        <target state="translated">Hello</target>
+      </trans-unit>
+      <trans-unit id="loco:5fd89b8542e5aa5cc27457e2" resname="index.greetings" datatype="plaintext" extradata="loco:format=icu">
+        <source>index.greetings</source>
+        <target state="translated">Welcome, {firstname}!</target>
+      </trans-unit>
+    </body>
+  </file>
+</xliff>
+XLIFF
+                    ,
+                    'fr' => <<<'XLIFF'
+<?xml version="1.0" encoding="UTF-8"?>
+<xliff xmlns="urn:oasis:names:tc:xliff:document:1.2" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="1.2" xsi:schemaLocation="urn:oasis:names:tc:xliff:document:1.2 http://docs.oasis-open.org/xliff/v1.2/os/xliff-core-1.2-strict.xsd">
+  <file original="https://localise.biz/user/symfony-translation-provider" source-language="en" datatype="database" tool-id="loco">
+    <header>
+      <tool tool-id="loco" tool-name="Loco" tool-version="1.0.25 20201211-1" tool-company="Loco"/>
+    </header>
+    <body>
+      <trans-unit id="loco:5fd89b853ee27904dd6c5f67" resname="index.hello" datatype="plaintext">
+        <source>index.hello</source>
+        <target state="translated">Bonjour</target>
+      </trans-unit>
+      <trans-unit id="loco:5fd89b8542e5aa5cc27457e2" resname="index.greetings" datatype="plaintext" extradata="loco:format=icu">
+        <source>index.greetings</source>
+        <target state="translated">Bienvenue, {firstname} !</target>
+      </trans-unit>
+    </body>
+  </file>
+</xliff>
+XLIFF
+                    ,
+                ],
+                'validators' => [
+                    'en' => <<<'XLIFF'
+<?xml version="1.0" encoding="UTF-8"?>
+<xliff xmlns="urn:oasis:names:tc:xliff:document:1.2" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="1.2" xsi:schemaLocation="urn:oasis:names:tc:xliff:document:1.2 http://docs.oasis-open.org/xliff/v1.2/os/xliff-core-1.2-strict.xsd">
+  <file original="https://localise.biz/user/symfony-translation-provider" source-language="en" datatype="database" tool-id="loco">
+    <header>
+      <tool tool-id="loco" tool-name="Loco" tool-version="1.0.25 20201211-1" tool-company="Loco"/>
+    </header>
+    <body>
+      <trans-unit id="loco:5fd89b853ee27904dd6c5f68" resname="firstname.error" datatype="plaintext">
+        <source>firstname.error</source>
+        <target state="translated">Firstname must contains only letters.</target>
+      </trans-unit>
+      <trans-unit id="loco:5fd89b8542e5aa5cc27457e3" resname="lastname.error" datatype="plaintext" extradata="loco:format=icu">
+        <source>lastname.error</source>
+        <target state="translated">Lastname must contains only letters.</target>
+      </trans-unit>
+    </body>
+  </file>
+</xliff>
+XLIFF
+                    ,
+                    'fr' => <<<'XLIFF'
+<?xml version="1.0" encoding="UTF-8"?>
+<xliff xmlns="urn:oasis:names:tc:xliff:document:1.2" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="1.2" xsi:schemaLocation="urn:oasis:names:tc:xliff:document:1.2 http://docs.oasis-open.org/xliff/v1.2/os/xliff-core-1.2-strict.xsd">
+  <file original="https://localise.biz/user/symfony-translation-provider" source-language="en" datatype="database" tool-id="loco">
+    <header>
+      <tool tool-id="loco" tool-name="Loco" tool-version="1.0.25 20201211-1" tool-company="Loco"/>
+    </header>
+    <body>
+      <trans-unit id="loco:5fd89b853ee27904dd6c5f68" resname="firstname.error" datatype="plaintext">
+        <source>firstname.error</source>
+        <target state="translated">Le prénom ne peut contenir que des lettres.</target>
+      </trans-unit>
+      <trans-unit id="loco:5fd89b8542e5aa5cc27457e3" resname="lastname.error" datatype="plaintext" extradata="loco:format=icu">
+        <source>lastname.error</source>
+        <target state="translated">Le nom de famille ne peut contenir que des lettres.</target>
+      </trans-unit>
+    </body>
+  </file>
+</xliff>
+XLIFF
+                    ,
+            ],
+            ],
+            [
+                'messages' => $expectedTranslatorBagMessages,
+                'validators' => $expectedTranslatorBagValidators,
+            ],
+        ];
+    }
+}
diff --git a/src/Symfony/Component/Translation/Bridge/Loco/composer.json b/src/Symfony/Component/Translation/Bridge/Loco/composer.json
new file mode 100644
index 0000000000..7b57c2646f
--- /dev/null
+++ b/src/Symfony/Component/Translation/Bridge/Loco/composer.json
@@ -0,0 +1,30 @@
+{
+    "name": "symfony/loco-translation",
+    "type": "symfony-bridge",
+    "description": "Symfony Loco Translation Bridge",
+    "keywords": ["loco", "translation", "provider"],
+    "homepage": "https://symfony.com",
+    "license": "MIT",
+    "authors": [
+        {
+            "name": "Mathieu Santostefano",
+            "homepage": "https://github.com/welcomattic"
+        },
+        {
+            "name": "Symfony Community",
+            "homepage": "https://symfony.com/contributors"
+        }
+    ],
+    "require": {
+        "php": ">=7.2.5",
+        "symfony/http-client": "^5.3",
+        "symfony/translation": "^5.3"
+    },
+    "autoload": {
+        "psr-4": { "Symfony\\Component\\Translation\\Bridge\\Loco\\": "" },
+        "exclude-from-classmap": [
+            "/Tests/"
+        ]
+    },
+    "minimum-stability": "dev"
+}
diff --git a/src/Symfony/Component/Translation/Bridge/Loco/phpunit.xml.dist b/src/Symfony/Component/Translation/Bridge/Loco/phpunit.xml.dist
new file mode 100644
index 0000000000..c58cb50d0e
--- /dev/null
+++ b/src/Symfony/Component/Translation/Bridge/Loco/phpunit.xml.dist
@@ -0,0 +1,31 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:noNamespaceSchemaLocation="http://schema.phpunit.de/5.2/phpunit.xsd"
+         backupGlobals="false"
+         colors="true"
+         bootstrap="vendor/autoload.php"
+         failOnRisky="true"
+         failOnWarning="true"
+>
+    <php>
+        <ini name="error_reporting" value="-1" />
+    </php>
+
+    <testsuites>
+        <testsuite name="Symfony Loco Translation Bridge Test Suite">
+            <directory>./Tests/</directory>
+        </testsuite>
+    </testsuites>
+
+    <filter>
+        <whitelist>
+            <directory>./</directory>
+            <exclude>
+                <directory>./Resources</directory>
+                <directory>./Tests</directory>
+                <directory>./vendor</directory>
+            </exclude>
+        </whitelist>
+    </filter>
+</phpunit>
diff --git a/src/Symfony/Component/Translation/CHANGELOG.md b/src/Symfony/Component/Translation/CHANGELOG.md
index b1eb2da062..1ff428b8e5 100644
--- a/src/Symfony/Component/Translation/CHANGELOG.md
+++ b/src/Symfony/Component/Translation/CHANGELOG.md
@@ -1,6 +1,11 @@
 CHANGELOG
 =========
 
+5.3
+---
+
+ * Add `translation:pull` and `translation:push` commands to manage translations with third-party providers
+
 5.2.0
 -----
 
diff --git a/src/Symfony/Component/Translation/Catalogue/AbstractOperation.php b/src/Symfony/Component/Translation/Catalogue/AbstractOperation.php
index 17c257fde4..9869fbb8bb 100644
--- a/src/Symfony/Component/Translation/Catalogue/AbstractOperation.php
+++ b/src/Symfony/Component/Translation/Catalogue/AbstractOperation.php
@@ -26,6 +26,10 @@ use Symfony\Component\Translation\MessageCatalogueInterface;
  */
 abstract class AbstractOperation implements OperationInterface
 {
+    public const OBSOLETE_BATCH = 'obsolete';
+    public const NEW_BATCH = 'new';
+    public const ALL_BATCH = 'all';
+
     protected $source;
     protected $target;
     protected $result;
@@ -94,11 +98,11 @@ abstract class AbstractOperation implements OperationInterface
             throw new InvalidArgumentException(sprintf('Invalid domain: "%s".', $domain));
         }
 
-        if (!isset($this->messages[$domain]['all'])) {
+        if (!isset($this->messages[$domain][self::ALL_BATCH])) {
             $this->processDomain($domain);
         }
 
-        return $this->messages[$domain]['all'];
+        return $this->messages[$domain][self::ALL_BATCH];
     }
 
     /**
@@ -110,11 +114,11 @@ abstract class AbstractOperation implements OperationInterface
             throw new InvalidArgumentException(sprintf('Invalid domain: "%s".', $domain));
         }
 
-        if (!isset($this->messages[$domain]['new'])) {
+        if (!isset($this->messages[$domain][self::NEW_BATCH])) {
             $this->processDomain($domain);
         }
 
-        return $this->messages[$domain]['new'];
+        return $this->messages[$domain][self::NEW_BATCH];
     }
 
     /**
@@ -126,11 +130,11 @@ abstract class AbstractOperation implements OperationInterface
             throw new InvalidArgumentException(sprintf('Invalid domain: "%s".', $domain));
         }
 
-        if (!isset($this->messages[$domain]['obsolete'])) {
+        if (!isset($this->messages[$domain][self::OBSOLETE_BATCH])) {
             $this->processDomain($domain);
         }
 
-        return $this->messages[$domain]['obsolete'];
+        return $this->messages[$domain][self::OBSOLETE_BATCH];
     }
 
     /**
@@ -147,6 +151,37 @@ abstract class AbstractOperation implements OperationInterface
         return $this->result;
     }
 
+    /**
+     * @param self::*_BATCH $batch
+     */
+    public function moveMessagesToIntlDomainsIfPossible(string $batch = self::ALL_BATCH): void
+    {
+        // If MessageFormatter class does not exists, intl domains are not supported.
+        if (!class_exists(\MessageFormatter::class)) {
+            return;
+        }
+
+        foreach ($this->getDomains() as $domain) {
+            $intlDomain = $domain.MessageCatalogueInterface::INTL_DOMAIN_SUFFIX;
+            switch ($batch) {
+                case self::OBSOLETE_BATCH: $messages = $this->getObsoleteMessages($domain); break;
+                case self::NEW_BATCH: $messages = $this->getNewMessages($domain); break;
+                case self::ALL_BATCH: $messages = $this->getMessages($domain); break;
+                default: throw new \InvalidArgumentException(sprintf('$batch argument must be one of ["%s", "%s", "%s"].', self::ALL_BATCH, self::NEW_BATCH, self::OBSOLETE_BATCH));
+            }
+
+            if (!$messages || (!$this->source->all($intlDomain) && $this->source->all($domain))) {
+                continue;
+            }
+
+            $result = $this->getResult();
+            $allIntlMessages = $result->all($intlDomain);
+            $currentMessages = array_diff_key($messages, $result->all($domain));
+            $result->replace($currentMessages, $domain);
+            $result->replace($allIntlMessages + $messages, $intlDomain);
+        }
+    }
+
     /**
      * Performs operation on source and target catalogues for the given domain and
      * stores the results.
diff --git a/src/Symfony/Component/Translation/Command/TranslationPullCommand.php b/src/Symfony/Component/Translation/Command/TranslationPullCommand.php
new file mode 100644
index 0000000000..0ec02ca7b2
--- /dev/null
+++ b/src/Symfony/Component/Translation/Command/TranslationPullCommand.php
@@ -0,0 +1,157 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Translation\Command;
+
+use Symfony\Component\Console\Command\Command;
+use Symfony\Component\Console\Input\InputArgument;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Input\InputOption;
+use Symfony\Component\Console\Output\OutputInterface;
+use Symfony\Component\Console\Style\SymfonyStyle;
+use Symfony\Component\Translation\Catalogue\TargetOperation;
+use Symfony\Component\Translation\MessageCatalogue;
+use Symfony\Component\Translation\Provider\TranslationProviderCollection;
+use Symfony\Component\Translation\Reader\TranslationReaderInterface;
+use Symfony\Component\Translation\Writer\TranslationWriterInterface;
+
+/**
+ * @author Mathieu Santostefano <msantostefano@protonmail.com>
+ *
+ * @experimental in 5.3
+ */
+final class TranslationPullCommand extends Command
+{
+    use TranslationTrait;
+
+    protected static $defaultName = 'translation:pull';
+    protected static $defaultDescription = 'Pull translations from a given provider.';
+
+    private $providerCollection;
+    private $writer;
+    private $reader;
+    private $defaultLocale;
+    private $transPaths;
+    private $enabledLocales;
+
+    public function __construct(TranslationProviderCollection $providerCollection, TranslationWriterInterface $writer, TranslationReaderInterface $reader, string $defaultLocale, array $transPaths = [], array $enabledLocales = [])
+    {
+        $this->providerCollection = $providerCollection;
+        $this->writer = $writer;
+        $this->reader = $reader;
+        $this->defaultLocale = $defaultLocale;
+        $this->transPaths = $transPaths;
+        $this->enabledLocales = $enabledLocales;
+
+        parent::__construct();
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    protected function configure()
+    {
+        $keys = $this->providerCollection->keys();
+        $defaultProvider = 1 === \count($keys) ? $keys[0] : null;
+
+        $this
+            ->setDefinition([
+                new InputArgument('provider', null !== $defaultProvider ? InputArgument::OPTIONAL : InputArgument::REQUIRED, 'The provider to pull translations from.', $defaultProvider),
+                new InputOption('force', null, InputOption::VALUE_NONE, 'Override existing translations with provider ones (it will delete not synchronized messages).'),
+                new InputOption('intl-icu', null, InputOption::VALUE_NONE, 'Associated to --force option, it will write messages in "%domain%+intl-icu.%locale%.xlf" files.'),
+                new InputOption('domains', null, InputOption::VALUE_OPTIONAL | InputOption::VALUE_IS_ARRAY, 'Specify the domains to pull.'),
+                new InputOption('locales', null, InputOption::VALUE_OPTIONAL | InputOption::VALUE_IS_ARRAY, 'Specify the locales to pull.'),
+                new InputOption('format', null, InputOption::VALUE_OPTIONAL, 'Override the default output format.', 'xlf12'),
+            ])
+            ->setHelp(<<<'EOF'
+The <info>%command.name%</> command pulls translations from the given provider. Only
+new translations are pulled, existing ones are not overwritten.
+
+You can overwrite existing translations (and remove the missing ones on local side) by using the <comment>--force</> flag:
+
+  <info>php %command.full_name% --force provider</>
+
+Full example:
+
+  <info>php %command.full_name% provider --force --domains=messages,validators --locales=en</>
+
+This command pulls all translations associated with the <comment>messages</> and <comment>validators</> domains for the <comment>en</> locale.
+Local translations for the specified domains and locale are deleted if they're not present on the provider and overwritten if it's the case.
+Local translations for others domains and locales are ignored.
+EOF
+            )
+        ;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    protected function execute(InputInterface $input, OutputInterface $output): int
+    {
+        $io = new SymfonyStyle($input, $output);
+
+        $provider = $this->providerCollection->get($input->getArgument('provider'));
+        $force = $input->getOption('force');
+        $intlIcu = $input->getOption('intl-icu');
+        $locales = $input->getOption('locales') ?: $this->enabledLocales;
+        $domains = $input->getOption('domains');
+        $format = $input->getOption('format');
+        $xliffVersion = '1.2';
+
+        if ($intlIcu && !$force) {
+            $io->note('--intl-icu option only has an effect when used with --force. Here, it will be ignored.');
+        }
+
+        switch ($format) {
+            case 'xlf20': $xliffVersion = '2.0';
+            // no break
+            case 'xlf12': $format = 'xlf';
+        }
+
+        $writeOptions = [
+            'path' => end($this->transPaths),
+            'xliff_version' => $xliffVersion,
+        ];
+
+        if (!$domains) {
+            $domains = $provider->getDomains();
+        }
+
+        $providerTranslations = $provider->read($domains, $locales);
+
+        if ($force) {
+            foreach ($providerTranslations->getCatalogues() as $catalogue) {
+                $operation = new TargetOperation((new MessageCatalogue($catalogue->getLocale())), $catalogue);
+                if ($intlIcu) {
+                    $operation->moveMessagesToIntlDomainsIfPossible();
+                }
+                $this->writer->write($operation->getResult(), $format, $writeOptions);
+            }
+
+            $io->success(sprintf('Local translations has been updated from "%s" (for "%s" locale(s), and "%s" domain(s)).', parse_url($provider, \PHP_URL_SCHEME), implode(', ', $locales), implode(', ', $domains)));
+
+            return 0;
+        }
+
+        $localTranslations = $this->readLocalTranslations($locales, $domains, $this->transPaths);
+
+        // Append pulled translations to local ones.
+        $localTranslations->addBag($providerTranslations->diff($localTranslations));
+
+        foreach ($localTranslations->getCatalogues() as $catalogue) {
+            $this->writer->write($catalogue, $format, $writeOptions);
+        }
+
+        $io->success(sprintf('New translations from "%s" has been written locally (for "%s" locale(s), and "%s" domain(s)).', parse_url($provider, \PHP_URL_SCHEME), implode(', ', $locales), implode(', ', $domains)));
+
+        return 0;
+    }
+}
diff --git a/src/Symfony/Component/Translation/Command/TranslationPushCommand.php b/src/Symfony/Component/Translation/Command/TranslationPushCommand.php
new file mode 100644
index 0000000000..da265d6c8b
--- /dev/null
+++ b/src/Symfony/Component/Translation/Command/TranslationPushCommand.php
@@ -0,0 +1,158 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Translation\Command;
+
+use Symfony\Component\Console\Command\Command;
+use Symfony\Component\Console\Exception\InvalidArgumentException;
+use Symfony\Component\Console\Input\InputArgument;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Input\InputOption;
+use Symfony\Component\Console\Output\OutputInterface;
+use Symfony\Component\Console\Style\SymfonyStyle;
+use Symfony\Component\Translation\Provider\TranslationProviderCollection;
+use Symfony\Component\Translation\Reader\TranslationReaderInterface;
+use Symfony\Component\Translation\TranslatorBag;
+
+/**
+ * @author Mathieu Santostefano <msantostefano@protonmail.com>
+ *
+ * @experimental in 5.3
+ */
+final class TranslationPushCommand extends Command
+{
+    use TranslationTrait;
+
+    protected static $defaultName = 'translation:push';
+    protected static $defaultDescription = 'Push translations to a given provider.';
+
+    private $providers;
+    private $reader;
+    private $transPaths;
+    private $enabledLocales;
+
+    public function __construct(TranslationProviderCollection $providers, TranslationReaderInterface $reader, array $transPaths = [], array $enabledLocales = [])
+    {
+        $this->providers = $providers;
+        $this->reader = $reader;
+        $this->transPaths = $transPaths;
+        $this->enabledLocales = $enabledLocales;
+
+        parent::__construct();
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    protected function configure()
+    {
+        $keys = $this->providers->keys();
+        $defaultProvider = 1 === \count($keys) ? $keys[0] : null;
+
+        $this
+            ->setDefinition([
+                new InputArgument('provider', null !== $defaultProvider ? InputArgument::OPTIONAL : InputArgument::REQUIRED, 'The provider to push translations to.', $defaultProvider),
+                new InputOption('force', null, InputOption::VALUE_NONE, 'Override existing translations with local ones (it will delete not synchronized messages).'),
+                new InputOption('delete-missing', null, InputOption::VALUE_NONE, 'Delete translations available on provider but not locally.'),
+                new InputOption('domains', null, InputOption::VALUE_OPTIONAL | InputOption::VALUE_IS_ARRAY, 'Specify the domains to push.'),
+                new InputOption('locales', null, InputOption::VALUE_OPTIONAL | InputOption::VALUE_IS_ARRAY, 'Specify the locales to push.', $this->enabledLocales),
+            ])
+            ->setHelp(<<<'EOF'
+The <info>%command.name%</> command pushes translations to the given provider. Only new
+translations are pushed, existing ones are not overwritten.
+
+You can overwrite existing translations by using the <comment>--force</> flag:
+
+  <info>php %command.full_name% --force provider</>
+
+You can delete provider translations which are not present locally by using the <comment>--delete-missing</> flag:
+
+  <info>php %command.full_name% --delete-missing provider</>
+
+Full example:
+
+  <info>php %command.full_name% provider --force --delete-missing --domains=messages,validators --locales=en</>
+
+This command pushes all translations associated with the <comment>messages</> and <comment>validators</> domains for the <comment>en</> locale.
+Provider translations for the specified domains and locale are deleted if they're not present locally and overwritten if it's the case.
+Provider translations for others domains and locales are ignored.
+EOF
+            )
+        ;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    protected function execute(InputInterface $input, OutputInterface $output): int
+    {
+        if (!$this->enabledLocales) {
+            throw new InvalidArgumentException('You must define "framework.translator.enabled_locales" or "framework.translator.providers.%s.locales" config key in order to work with translation providers.');
+        }
+
+        $io = new SymfonyStyle($input, $output);
+
+        $provider = $this->providers->get($input->getArgument('provider'));
+        $domains = $input->getOption('domains');
+        $locales = $input->getOption('locales');
+        $force = $input->getOption('force');
+        $deleteMissing = $input->getOption('delete-missing');
+
+        $localTranslations = $this->readLocalTranslations($locales, $domains, $this->transPaths);
+
+        if (!$domains) {
+            $domains = $this->getDomainsFromTranslatorBag($localTranslations);
+        }
+
+        if (!$deleteMissing && $force) {
+            $provider->write($localTranslations);
+
+            $io->success(sprintf('All local translations has been sent to "%s" (for "%s" locale(s), and "%s" domain(s)).', parse_url($provider, \PHP_URL_SCHEME), implode(', ', $locales), implode(', ', $domains)));
+
+            return 0;
+        }
+
+        $providerTranslations = $provider->read($domains, $locales);
+
+        if ($deleteMissing) {
+            $provider->delete($providerTranslations->diff($localTranslations));
+
+            $io->success(sprintf('Missing translations on "%s" has been deleted (for "%s" locale(s), and "%s" domain(s)).', parse_url($provider, \PHP_URL_SCHEME), implode(', ', $locales), implode(', ', $domains)));
+
+            // Read provider translations again, after missing translations deletion,
+            // to avoid push freshly deleted translations.
+            $providerTranslations = $provider->read($domains, $locales);
+        }
+
+        $translationsToWrite = $localTranslations->diff($providerTranslations);
+
+        if ($force) {
+            $translationsToWrite->addBag($localTranslations->intersect($providerTranslations));
+        }
+
+        $provider->write($translationsToWrite);
+
+        $io->success(sprintf('%s local translations has been sent to "%s" (for "%s" locale(s), and "%s" domain(s)).', $force ? 'All' : 'New', parse_url($provider, \PHP_URL_SCHEME), implode(', ', $locales), implode(', ', $domains)));
+
+        return 0;
+    }
+
+    private function getDomainsFromTranslatorBag(TranslatorBag $translatorBag): array
+    {
+        $domains = [];
+
+        foreach ($translatorBag->getCatalogues() as $catalogue) {
+            $domains += $catalogue->getDomains();
+        }
+
+        return array_unique($domains);
+    }
+}
diff --git a/src/Symfony/Component/Translation/Command/TranslationTrait.php b/src/Symfony/Component/Translation/Command/TranslationTrait.php
new file mode 100644
index 0000000000..6a2b1ba86d
--- /dev/null
+++ b/src/Symfony/Component/Translation/Command/TranslationTrait.php
@@ -0,0 +1,78 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Translation\Command;
+
+use Symfony\Component\Translation\MessageCatalogue;
+use Symfony\Component\Translation\MessageCatalogueInterface;
+use Symfony\Component\Translation\TranslatorBag;
+
+/**
+ * @internal
+ */
+trait TranslationTrait
+{
+    private function readLocalTranslations(array $locales, array $domains, array $transPaths): TranslatorBag
+    {
+        $bag = new TranslatorBag();
+
+        foreach ($locales as $locale) {
+            $catalogue = new MessageCatalogue($locale);
+            foreach ($transPaths as $path) {
+                $this->reader->read($path, $catalogue);
+            }
+
+            if ($domains) {
+                foreach ($domains as $domain) {
+                    $catalogue = $this->filterCatalogue($catalogue, $domain);
+                    $bag->addCatalogue($catalogue);
+                }
+            } else {
+                $bag->addCatalogue($catalogue);
+            }
+        }
+
+        return $bag;
+    }
+
+    private function filterCatalogue(MessageCatalogue $catalogue, string $domain): MessageCatalogue
+    {
+        $filteredCatalogue = new MessageCatalogue($catalogue->getLocale());
+
+        // extract intl-icu messages only
+        $intlDomain = $domain.MessageCatalogueInterface::INTL_DOMAIN_SUFFIX;
+        if ($intlMessages = $catalogue->all($intlDomain)) {
+            $filteredCatalogue->add($intlMessages, $intlDomain);
+        }
+
+        // extract all messages and subtract intl-icu messages
+        if ($messages = array_diff($catalogue->all($domain), $intlMessages)) {
+            $filteredCatalogue->add($messages, $domain);
+        }
+        foreach ($catalogue->getResources() as $resource) {
+            $filteredCatalogue->addResource($resource);
+        }
+
+        if ($metadata = $catalogue->getMetadata('', $intlDomain)) {
+            foreach ($metadata as $k => $v) {
+                $filteredCatalogue->setMetadata($k, $v, $intlDomain);
+            }
+        }
+
+        if ($metadata = $catalogue->getMetadata('', $domain)) {
+            foreach ($metadata as $k => $v) {
+                $filteredCatalogue->setMetadata($k, $v, $domain);
+            }
+        }
+
+        return $filteredCatalogue;
+    }
+}
diff --git a/src/Symfony/Component/Translation/DataCollectorTranslator.php b/src/Symfony/Component/Translation/DataCollectorTranslator.php
index ed5008e1c7..c7d3597542 100644
--- a/src/Symfony/Component/Translation/DataCollectorTranslator.php
+++ b/src/Symfony/Component/Translation/DataCollectorTranslator.php
@@ -79,6 +79,14 @@ class DataCollectorTranslator implements TranslatorInterface, TranslatorBagInter
         return $this->translator->getCatalogue($locale);
     }
 
+    /**
+     * {@inheritdoc}
+     */
+    public function getCatalogues(): array
+    {
+        return $this->translator->getCatalogues();
+    }
+
     /**
      * {@inheritdoc}
      *
diff --git a/src/Symfony/Component/Translation/Exception/IncompleteDsnException.php b/src/Symfony/Component/Translation/Exception/IncompleteDsnException.php
new file mode 100644
index 0000000000..192de3c657
--- /dev/null
+++ b/src/Symfony/Component/Translation/Exception/IncompleteDsnException.php
@@ -0,0 +1,24 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Translation\Exception;
+
+class IncompleteDsnException extends InvalidArgumentException
+{
+    public function __construct(string $message, string $dsn = null, ?\Throwable $previous = null)
+    {
+        if ($dsn) {
+            $message = sprintf('Invalid "%s" provider DSN: ', $dsn).$message;
+        }
+
+        parent::__construct($message, 0, $previous);
+    }
+}
diff --git a/src/Symfony/Component/Translation/Exception/ProviderException.php b/src/Symfony/Component/Translation/Exception/ProviderException.php
new file mode 100644
index 0000000000..659c6d7721
--- /dev/null
+++ b/src/Symfony/Component/Translation/Exception/ProviderException.php
@@ -0,0 +1,43 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Translation\Exception;
+
+use Symfony\Contracts\HttpClient\ResponseInterface;
+
+/**
+ * @author Fabien Potencier <fabien@symfony.com>
+ *
+ * @experimental in 5.3
+ */
+class ProviderException extends RuntimeException implements ProviderExceptionInterface
+{
+    private $response;
+    private $debug;
+
+    public function __construct(string $message, ResponseInterface $response, int $code = 0, \Exception $previous = null)
+    {
+        $this->response = $response;
+        $this->debug .= $response->getInfo('debug') ?? '';
+
+        parent::__construct($message, $code, $previous);
+    }
+
+    public function getResponse(): ResponseInterface
+    {
+        return $this->response;
+    }
+
+    public function getDebug(): string
+    {
+        return $this->debug;
+    }
+}
diff --git a/src/Symfony/Component/Translation/Exception/ProviderExceptionInterface.php b/src/Symfony/Component/Translation/Exception/ProviderExceptionInterface.php
new file mode 100644
index 0000000000..8cf1c51c3d
--- /dev/null
+++ b/src/Symfony/Component/Translation/Exception/ProviderExceptionInterface.php
@@ -0,0 +1,25 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Translation\Exception;
+
+/**
+ * @author Fabien Potencier <fabien@symfony.com>
+ *
+ * @experimental in 5.3
+ */
+interface ProviderExceptionInterface extends ExceptionInterface
+{
+    /*
+     * Returns debug info coming from the Symfony\Contracts\HttpClient\ResponseInterface
+     */
+    public function getDebug(): string;
+}
diff --git a/src/Symfony/Component/Translation/Exception/UnsupportedSchemeException.php b/src/Symfony/Component/Translation/Exception/UnsupportedSchemeException.php
new file mode 100644
index 0000000000..d53f3b0118
--- /dev/null
+++ b/src/Symfony/Component/Translation/Exception/UnsupportedSchemeException.php
@@ -0,0 +1,46 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Translation\Exception;
+
+use Symfony\Component\Translation\Bridge;
+use Symfony\Component\Translation\Provider\Dsn;
+
+class UnsupportedSchemeException extends LogicException
+{
+    private const SCHEME_TO_PACKAGE_MAP = [
+        'loco' => [
+            'class' => Bridge\Loco\Provider\LocoProviderFactory::class,
+            'package' => 'symfony/loco-translation',
+        ],
+    ];
+
+    public function __construct(Dsn $dsn, string $name = null, array $supported = [])
+    {
+        $provider = $dsn->getScheme();
+        if (false !== $pos = strpos($provider, '+')) {
+            $provider = substr($provider, 0, $pos);
+        }
+        $package = self::SCHEME_TO_PACKAGE_MAP[$provider] ?? null;
+        if ($package && !class_exists($package['class'])) {
+            parent::__construct(sprintf('Unable to synchronize translations via "%s" as the providers is not installed; try running "composer require %s".', $provider, $package['package']));
+
+            return;
+        }
+
+        $message = sprintf('The "%s" scheme is not supported', $dsn->getScheme());
+        if ($name && $supported) {
+            $message .= sprintf('; supported schemes for translation providers "%s" are: "%s"', $name, implode('", "', $supported));
+        }
+
+        parent::__construct($message.'.');
+    }
+}
diff --git a/src/Symfony/Component/Translation/Loader/XliffFileLoader.php b/src/Symfony/Component/Translation/Loader/XliffFileLoader.php
index f573dfe4c7..2029fed928 100644
--- a/src/Symfony/Component/Translation/Loader/XliffFileLoader.php
+++ b/src/Symfony/Component/Translation/Loader/XliffFileLoader.php
@@ -12,6 +12,8 @@
 namespace Symfony\Component\Translation\Loader;
 
 use Symfony\Component\Config\Resource\FileResource;
+use Symfony\Component\Config\Util\Exception\InvalidXmlException;
+use Symfony\Component\Config\Util\Exception\XmlParsingException;
 use Symfony\Component\Config\Util\XmlUtils;
 use Symfony\Component\Translation\Exception\InvalidResourceException;
 use Symfony\Component\Translation\Exception\NotFoundResourceException;
@@ -35,36 +37,47 @@ class XliffFileLoader implements LoaderInterface
             throw new RuntimeException('Loading translations from the Xliff format requires the Symfony Config component.');
         }
 
-        if (!stream_is_local($resource)) {
-            throw new InvalidResourceException(sprintf('This is not a local file "%s".', $resource));
+        if (!$this->isXmlString($resource)) {
+            if (!stream_is_local($resource)) {
+                throw new InvalidResourceException(sprintf('This is not a local file "%s".', $resource));
+            }
+
+            if (!file_exists($resource)) {
+                throw new NotFoundResourceException(sprintf('File "%s" not found.', $resource));
+            }
+
+            if (!is_file($resource)) {
+                throw new InvalidResourceException(sprintf('This is neither a file nor an XLIFF string "%s".', $resource));
+            }
         }
 
-        if (!file_exists($resource)) {
-            throw new NotFoundResourceException(sprintf('File "%s" not found.', $resource));
+        try {
+            if ($this->isXmlString($resource)) {
+                $dom = XmlUtils::parse($resource);
+            } else {
+                $dom = XmlUtils::loadFile($resource);
+            }
+        } catch (\InvalidArgumentException | XmlParsingException | InvalidXmlException $e) {
+            throw new InvalidResourceException(sprintf('Unable to load "%s": ', $resource).$e->getMessage(), $e->getCode(), $e);
+        }
+
+        if ($errors = XliffUtils::validateSchema($dom)) {
+            throw new InvalidResourceException(sprintf('Invalid resource provided: "%s"; Errors: ', $resource).XliffUtils::getErrorsAsString($errors));
         }
 
         $catalogue = new MessageCatalogue($locale);
-        $this->extract($resource, $catalogue, $domain);
+        $this->extract($dom, $catalogue, $domain);
 
-        if (class_exists(FileResource::class)) {
+        if (is_file($resource) && class_exists(FileResource::class)) {
             $catalogue->addResource(new FileResource($resource));
         }
 
         return $catalogue;
     }
 
-    private function extract($resource, MessageCatalogue $catalogue, string $domain)
+    private function extract($dom, MessageCatalogue $catalogue, string $domain)
     {
-        try {
-            $dom = XmlUtils::loadFile($resource);
-        } catch (\InvalidArgumentException $e) {
-            throw new InvalidResourceException(sprintf('Unable to load "%s": ', $resource).$e->getMessage(), $e->getCode(), $e);
-        }
-
         $xliffVersion = XliffUtils::getVersionNumber($dom);
-        if ($errors = XliffUtils::validateSchema($dom)) {
-            throw new InvalidResourceException(sprintf('Invalid resource provided: "%s"; Errors: ', $resource).XliffUtils::getErrorsAsString($errors));
-        }
 
         if ('1.2' === $xliffVersion) {
             $this->extractXliff1($dom, $catalogue, $domain);
@@ -211,4 +224,9 @@ class XliffFileLoader implements LoaderInterface
 
         return $notes;
     }
+
+    private function isXmlString(string $resource): bool
+    {
+        return 0 === strpos($resource, '<?xml');
+    }
 }
diff --git a/src/Symfony/Component/Translation/LoggingTranslator.php b/src/Symfony/Component/Translation/LoggingTranslator.php
index 9e72ecbd7e..bb93435c30 100644
--- a/src/Symfony/Component/Translation/LoggingTranslator.php
+++ b/src/Symfony/Component/Translation/LoggingTranslator.php
@@ -82,6 +82,14 @@ class LoggingTranslator implements TranslatorInterface, TranslatorBagInterface,
         return $this->translator->getCatalogue($locale);
     }
 
+    /**
+     * {@inheritdoc}
+     */
+    public function getCatalogues(): array
+    {
+        return $this->translator->getCatalogues();
+    }
+
     /**
      * Gets the fallback locales.
      *
diff --git a/src/Symfony/Component/Translation/Provider/AbstractProviderFactory.php b/src/Symfony/Component/Translation/Provider/AbstractProviderFactory.php
new file mode 100644
index 0000000000..17442fde87
--- /dev/null
+++ b/src/Symfony/Component/Translation/Provider/AbstractProviderFactory.php
@@ -0,0 +1,45 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Translation\Provider;
+
+use Symfony\Component\Translation\Exception\IncompleteDsnException;
+
+abstract class AbstractProviderFactory implements ProviderFactoryInterface
+{
+    public function supports(Dsn $dsn): bool
+    {
+        return \in_array($dsn->getScheme(), $this->getSupportedSchemes(), true);
+    }
+
+    /**
+     * @return string[]
+     */
+    abstract protected function getSupportedSchemes(): array;
+
+    protected function getUser(Dsn $dsn): string
+    {
+        if (null === $user = $dsn->getUser()) {
+            throw new IncompleteDsnException('User is not set.', $dsn->getOriginalDsn());
+        }
+
+        return $user;
+    }
+
+    protected function getPassword(Dsn $dsn): string
+    {
+        if (null === $password = $dsn->getPassword()) {
+            throw new IncompleteDsnException('Password is not set.', $dsn->getOriginalDsn());
+        }
+
+        return $password;
+    }
+}
diff --git a/src/Symfony/Component/Translation/Provider/Dsn.php b/src/Symfony/Component/Translation/Provider/Dsn.php
new file mode 100644
index 0000000000..67f805c9d8
--- /dev/null
+++ b/src/Symfony/Component/Translation/Provider/Dsn.php
@@ -0,0 +1,108 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Translation\Provider;
+
+use Symfony\Component\Translation\Exception\InvalidArgumentException;
+
+/**
+ * @author Mathieu Santostefano <msantostefano@protonmail.com>
+ *
+ * @experimental in 5.3
+ */
+final class Dsn
+{
+    private $scheme;
+    private $host;
+    private $user;
+    private $password;
+    private $port;
+    private $options;
+    private $path;
+    private $dsn;
+
+    public function __construct(string $scheme, string $host, ?string $user = null, ?string $password = null, ?int $port = null, array $options = [], ?string $path = null)
+    {
+        $this->scheme = $scheme;
+        $this->host = $host;
+        $this->user = $user;
+        $this->password = $password;
+        $this->port = $port;
+        $this->options = $options;
+        $this->path = $path;
+    }
+
+    public static function fromString(string $dsn): self
+    {
+        if (false === $parsedDsn = parse_url($dsn)) {
+            throw new InvalidArgumentException(sprintf('The "%s" translation provider DSN is invalid.', $dsn));
+        }
+
+        if (!isset($parsedDsn['scheme'])) {
+            throw new InvalidArgumentException(sprintf('The "%s" translation provider DSN must contain a scheme.', $dsn));
+        }
+
+        if (!isset($parsedDsn['host'])) {
+            throw new InvalidArgumentException(sprintf('The "%s" translation provider DSN must contain a host (use "default" by default).', $dsn));
+        }
+
+        $user = isset($parsedDsn['user']) ? urldecode($parsedDsn['user']) : null;
+        $password = isset($parsedDsn['pass']) ? urldecode($parsedDsn['pass']) : null;
+        $port = $parsedDsn['port'] ?? null;
+        $path = $parsedDsn['path'] ?? null;
+        parse_str($parsedDsn['query'] ?? '', $query);
+
+        $dsnObject = new self($parsedDsn['scheme'], $parsedDsn['host'], $user, $password, $port, $query, $path);
+        $dsnObject->dsn = $dsn;
+
+        return $dsnObject;
+    }
+
+    public function getScheme(): string
+    {
+        return $this->scheme;
+    }
+
+    public function getHost(): string
+    {
+        return $this->host;
+    }
+
+    public function getUser(): ?string
+    {
+        return $this->user;
+    }
+
+    public function getPassword(): ?string
+    {
+        return $this->password;
+    }
+
+    public function getPort(int $default = null): ?int
+    {
+        return $this->port ?? $default;
+    }
+
+    public function getOption(string $key, $default = null)
+    {
+        return $this->options[$key] ?? $default;
+    }
+
+    public function getPath(): ?string
+    {
+        return $this->path;
+    }
+
+    public function getOriginalDsn(): string
+    {
+        return $this->dsn;
+    }
+}
diff --git a/src/Symfony/Component/Translation/Provider/FilteringProvider.php b/src/Symfony/Component/Translation/Provider/FilteringProvider.php
new file mode 100644
index 0000000000..0307cdacf0
--- /dev/null
+++ b/src/Symfony/Component/Translation/Provider/FilteringProvider.php
@@ -0,0 +1,67 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Translation\Provider;
+
+use Symfony\Component\Translation\TranslatorBag;
+use Symfony\Component\Translation\TranslatorBagInterface;
+
+/**
+ * Filters domains and locales between the Translator config values and those specific to each provider.
+ *
+ * @author Mathieu Santostefano <msantostefano@protonmail.com>
+ *
+ * @experimental in 5.3
+ */
+class FilteringProvider implements ProviderInterface
+{
+    private $provider;
+    private $locales;
+    private $domains;
+
+    public function __construct(ProviderInterface $provider, array $locales, array $domains = [])
+    {
+        $this->provider = $provider;
+        $this->locales = $locales;
+        $this->domains = $domains;
+    }
+
+    public function __toString(): string
+    {
+        return (string) $this->provider;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function write(TranslatorBagInterface $translatorBag): void
+    {
+        $this->provider->write($translatorBag);
+    }
+
+    public function read(array $domains, array $locales): TranslatorBag
+    {
+        $domains = !$this->domains ? $domains : array_intersect($this->domains, $domains);
+        $locales = array_intersect($this->locales, $locales);
+
+        return $this->provider->read($domains, $locales);
+    }
+
+    public function delete(TranslatorBagInterface $translatorBag): void
+    {
+        $this->provider->delete($translatorBag);
+    }
+
+    public function getDomains(): array
+    {
+        return $this->domains;
+    }
+}
diff --git a/src/Symfony/Component/Translation/Provider/NullProvider.php b/src/Symfony/Component/Translation/Provider/NullProvider.php
new file mode 100644
index 0000000000..f180a5030c
--- /dev/null
+++ b/src/Symfony/Component/Translation/Provider/NullProvider.php
@@ -0,0 +1,41 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Translation\Provider;
+
+use Symfony\Component\Translation\TranslatorBag;
+use Symfony\Component\Translation\TranslatorBagInterface;
+
+/**
+ * @author Mathieu Santostefano <msantostefano@protonmail.com>
+ *
+ * @experimental in 5.3
+ */
+class NullProvider implements ProviderInterface
+{
+    public function __toString(): string
+    {
+        return NullProviderFactory::SCHEME.'://default';
+    }
+
+    public function write(TranslatorBagInterface $translatorBag, bool $override = false): void
+    {
+    }
+
+    public function read(array $domains, array $locales): TranslatorBag
+    {
+        return new TranslatorBag();
+    }
+
+    public function delete(TranslatorBagInterface $translatorBag): void
+    {
+    }
+}
diff --git a/src/Symfony/Component/Translation/Provider/NullProviderFactory.php b/src/Symfony/Component/Translation/Provider/NullProviderFactory.php
new file mode 100644
index 0000000000..81a02df6b2
--- /dev/null
+++ b/src/Symfony/Component/Translation/Provider/NullProviderFactory.php
@@ -0,0 +1,38 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Translation\Provider;
+
+use Symfony\Component\Translation\Exception\UnsupportedSchemeException;
+
+/**
+ * @author Mathieu Santostefano <msantostefano@protonmail.com>
+ *
+ * @experimental in 5.3
+ */
+final class NullProviderFactory extends AbstractProviderFactory
+{
+    const SCHEME = 'null';
+
+    public function create(Dsn $dsn): ProviderInterface
+    {
+        if (self::SCHEME === $dsn->getScheme()) {
+            return new NullProvider();
+        }
+
+        throw new UnsupportedSchemeException($dsn, self::SCHEME, $this->getSupportedSchemes());
+    }
+
+    protected function getSupportedSchemes(): array
+    {
+        return [self::SCHEME];
+    }
+}
diff --git a/src/Symfony/Component/Translation/Provider/ProviderFactoryInterface.php b/src/Symfony/Component/Translation/Provider/ProviderFactoryInterface.php
new file mode 100644
index 0000000000..3fd4494b4a
--- /dev/null
+++ b/src/Symfony/Component/Translation/Provider/ProviderFactoryInterface.php
@@ -0,0 +1,26 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Translation\Provider;
+
+use Symfony\Component\Translation\Exception\IncompleteDsnException;
+use Symfony\Component\Translation\Exception\UnsupportedSchemeException;
+
+interface ProviderFactoryInterface
+{
+    /**
+     * @throws UnsupportedSchemeException
+     * @throws IncompleteDsnException
+     */
+    public function create(Dsn $dsn): ProviderInterface;
+
+    public function supports(Dsn $dsn): bool;
+}
diff --git a/src/Symfony/Component/Translation/Provider/ProviderInterface.php b/src/Symfony/Component/Translation/Provider/ProviderInterface.php
new file mode 100644
index 0000000000..a32193f29c
--- /dev/null
+++ b/src/Symfony/Component/Translation/Provider/ProviderInterface.php
@@ -0,0 +1,32 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Translation\Provider;
+
+use Symfony\Component\Translation\TranslatorBag;
+use Symfony\Component\Translation\TranslatorBagInterface;
+
+interface ProviderInterface
+{
+    public function __toString(): string;
+
+    /**
+     * Translations available in the TranslatorBag only must be created.
+     * Translations available in both the TranslatorBag and on the provider
+     * must be overwritten.
+     * Translations available on the provider only must be kept.
+     */
+    public function write(TranslatorBagInterface $translatorBag): void;
+
+    public function read(array $domains, array $locales): TranslatorBag;
+
+    public function delete(TranslatorBagInterface $translatorBag): void;
+}
diff --git a/src/Symfony/Component/Translation/Provider/TranslationProviderCollection.php b/src/Symfony/Component/Translation/Provider/TranslationProviderCollection.php
new file mode 100644
index 0000000000..9963cb9f8c
--- /dev/null
+++ b/src/Symfony/Component/Translation/Provider/TranslationProviderCollection.php
@@ -0,0 +1,59 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Translation\Provider;
+
+use Symfony\Component\Translation\Exception\InvalidArgumentException;
+
+/**
+ * @author Mathieu Santostefano <msantostefano@protonmail.com>
+ *
+ * @experimental in 5.3
+ */
+final class TranslationProviderCollection
+{
+    private $providers;
+
+    /**
+     * @param array<string, ProviderInterface> $providers
+     */
+    public function __construct(iterable $providers)
+    {
+        $this->providers = [];
+        foreach ($providers as $name => $provider) {
+            $this->providers[$name] = $provider;
+        }
+    }
+
+    public function __toString(): string
+    {
+        return '['.implode(',', array_keys($this->providers)).']';
+    }
+
+    public function has(string $name): bool
+    {
+        return isset($this->providers[$name]);
+    }
+
+    public function get(string $name): ProviderInterface
+    {
+        if (!$this->has($name)) {
+            throw new InvalidArgumentException(sprintf('Provider "%s" not found. Available: "%s".', $name, (string) $this));
+        }
+
+        return $this->providers[$name];
+    }
+
+    public function keys(): array
+    {
+        return array_keys($this->providers);
+    }
+}
diff --git a/src/Symfony/Component/Translation/Provider/TranslationProviderCollectionFactory.php b/src/Symfony/Component/Translation/Provider/TranslationProviderCollectionFactory.php
new file mode 100644
index 0000000000..5c0b1eab7c
--- /dev/null
+++ b/src/Symfony/Component/Translation/Provider/TranslationProviderCollectionFactory.php
@@ -0,0 +1,59 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Translation\Provider;
+
+use Symfony\Component\Translation\Exception\UnsupportedSchemeException;
+
+/**
+ * @author Mathieu Santostefano <msantostefano@protonmail.com>
+ *
+ * @experimental in 5.3
+ */
+class TranslationProviderCollectionFactory
+{
+    private $factories;
+    private $enabledLocales;
+
+    /**
+     * @param ProviderFactoryInterface[] $factories
+     */
+    public function __construct(iterable $factories, array $enabledLocales)
+    {
+        $this->factories = $factories;
+        $this->enabledLocales = $enabledLocales;
+    }
+
+    public function fromConfig(array $config): TranslationProviderCollection
+    {
+        $providers = [];
+        foreach ($config as $name => $currentConfig) {
+            $providers[$name] = $this->fromDsnObject(
+                Dsn::fromString($currentConfig['dsn']),
+                !$currentConfig['locales'] ? $this->enabledLocales : $currentConfig['locales'],
+                !$currentConfig['domains'] ? [] : $currentConfig['domains']
+            );
+        }
+
+        return new TranslationProviderCollection($providers);
+    }
+
+    public function fromDsnObject(Dsn $dsn, array $locales, array $domains = []): ProviderInterface
+    {
+        foreach ($this->factories as $factory) {
+            if ($factory->supports($dsn)) {
+                return new FilteringProvider($factory->create($dsn), $locales, $domains);
+            }
+        }
+
+        throw new UnsupportedSchemeException($dsn);
+    }
+}
diff --git a/src/Symfony/Component/Translation/Tests/Command/TranslationProviderTestCase.php b/src/Symfony/Component/Translation/Tests/Command/TranslationProviderTestCase.php
new file mode 100644
index 0000000000..c490fa096c
--- /dev/null
+++ b/src/Symfony/Component/Translation/Tests/Command/TranslationProviderTestCase.php
@@ -0,0 +1,113 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Translation\Tests\Command;
+
+use PHPUnit\Framework\TestCase;
+use Psr\Log\LoggerInterface;
+use Symfony\Component\Filesystem\Filesystem;
+use Symfony\Component\HttpClient\MockHttpClient;
+use Symfony\Component\HttpClient\Response\CommonResponseTrait;
+use Symfony\Component\Translation\Bridge\Loco\Provider\LocoProvider;
+use Symfony\Component\Translation\Loader\LoaderInterface;
+use Symfony\Component\Translation\Loader\XliffFileLoader;
+use Symfony\Component\Translation\Provider\FilteringProvider;
+use Symfony\Component\Translation\Provider\ProviderInterface;
+use Symfony\Component\Translation\Provider\TranslationProviderCollection;
+use Symfony\Component\Translation\TranslatorBag;
+use Symfony\Contracts\HttpClient\ResponseInterface;
+
+/**
+ * @author Mathieu Santostefano <msantostefano@protonmail.com>
+ */
+abstract class TranslationProviderTestCase extends TestCase
+{
+    protected $fs;
+    protected $translationAppDir;
+    protected $files;
+    protected $defaultLocale;
+
+    protected function setUp(): void
+    {
+        parent::setUp();
+        $this->defaultLocale = \Locale::getDefault();
+        \Locale::setDefault('en');
+        $this->fs = new Filesystem();
+        $this->translationAppDir = sys_get_temp_dir().'/'.uniqid('sf_translation', true);
+        $this->fs->mkdir($this->translationAppDir.'/translations');
+    }
+
+    protected function tearDown(): void
+    {
+        \Locale::setDefault($this->defaultLocale);
+        $this->fs->remove($this->translationAppDir);
+        parent::tearDown();
+    }
+
+    protected function getProviderCollection(ProviderInterface $provider, array $locales = ['en'], array $domains = ['messages']): TranslationProviderCollection
+    {
+        return new TranslationProviderCollection([
+            'loco' => new FilteringProvider($provider, $locales, $domains),
+        ]);
+    }
+
+    protected function createFile(array $messages = ['note' => 'NOTE'], $targetLanguage = 'en', $fileNamePattern = 'messages.%locale%.xlf', string $xlfVersion = 'xlf12'): string
+    {
+        if ($xlfVersion === 'xlf12') {
+            $transUnits = '';
+            foreach ($messages as $key => $value) {
+                $transUnits .= <<<XLIFF
+<trans-unit id="$key">
+    <source>$key</source>
+    <target>$value</target>
+</trans-unit>
+XLIFF;
+            }
+            $xliffContent = <<<XLIFF
+<?xml version="1.0"?>
+<xliff version="1.2" xmlns="urn:oasis:names:tc:xliff:document:1.2">
+    <file source-language="en" target-language="$targetLanguage" datatype="plaintext" original="file.ext">
+        <body>
+            $transUnits
+        </body>
+    </file>
+</xliff>
+XLIFF;
+        } else {
+            $units = '';
+            foreach ($messages as $key => $value) {
+                $units .= <<<XLIFF
+<unit id="$key">
+  <segment>
+    <source>$key</source>
+    <target>$value</target>
+  </segment>
+</unit>
+XLIFF;
+            }
+            $xliffContent = <<<XLIFF
+<?xml version="1.0" encoding="utf-8"?>
+<xliff xmlns="urn:oasis:names:tc:xliff:document:2.0" version="2.0" srcLang="en" trgLang="$targetLanguage">
+  <file id="messages.$targetLanguage">
+    $units
+  </file>
+</xliff>
+XLIFF;
+        }
+
+        $filename = sprintf('%s/%s', $this->translationAppDir.'/translations', str_replace('%locale%', $targetLanguage, $fileNamePattern));
+        file_put_contents($filename, $xliffContent);
+
+        $this->files[] = $filename;
+
+        return $filename;
+    }
+}
diff --git a/src/Symfony/Component/Translation/Tests/Command/TranslationPullCommandTest.php b/src/Symfony/Component/Translation/Tests/Command/TranslationPullCommandTest.php
new file mode 100644
index 0000000000..0d5793e37d
--- /dev/null
+++ b/src/Symfony/Component/Translation/Tests/Command/TranslationPullCommandTest.php
@@ -0,0 +1,356 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Translation\Tests\Command;
+
+use Symfony\Component\Console\Application;
+use Symfony\Component\Console\Tester\CommandTester;
+use Symfony\Component\Translation\Command\TranslationPullCommand;
+use Symfony\Component\Translation\Dumper\XliffFileDumper;
+use Symfony\Component\Translation\Loader\ArrayLoader;
+use Symfony\Component\Translation\Loader\XliffFileLoader;
+use Symfony\Component\Translation\Provider\ProviderInterface;
+use Symfony\Component\Translation\Reader\TranslationReader;
+use Symfony\Component\Translation\TranslatorBag;
+use Symfony\Component\Translation\Writer\TranslationWriter;
+
+/**
+ * @author Mathieu Santostefano <msantostefano@protonmail.com>
+ */
+class TranslationPullCommandTest extends TranslationProviderTestCase
+{
+    public function testPullNewXlf12Messages()
+    {
+        $arrayLoader = new ArrayLoader();
+        $filenameEn = $this->createFile();
+        $filenameFr = $this->createFile(['note' => 'NOTE'], 'fr');
+        $locales = ['en', 'fr'];
+        $domains = ['messages'];
+
+        $providerReadTranslatorBag = new TranslatorBag();
+        $providerReadTranslatorBag->addCatalogue($arrayLoader->load([
+            'note' => 'NOTE',
+            'new.foo' => 'newFoo',
+        ], 'en'));
+        $providerReadTranslatorBag->addCatalogue($arrayLoader->load([
+            'note' => 'NOTE',
+            'new.foo' => 'nouveauFoo',
+        ], 'fr'));
+
+        $provider = $this->createMock(ProviderInterface::class);
+        $provider->expects($this->once())
+            ->method('read')
+            ->with($domains, $locales)
+            ->willReturn($providerReadTranslatorBag);
+
+        $provider->expects($this->once())
+            ->method('__toString')
+            ->willReturn('null://default');
+
+        $tester = $this->createCommandTester($provider, $locales, $domains);
+        $tester->execute(['--locales' => ['en', 'fr'], '--domains' => ['messages']]);
+
+        $this->assertStringContainsString('[OK] New translations from "null" has been written locally (for "en, fr" locale(s), and "messages" domain(s)).', trim($tester->getDisplay()));
+        $this->assertXmlStringEqualsXmlString(<<<XLIFF
+<?xml version="1.0"?>
+<xliff version="1.2" xmlns="urn:oasis:names:tc:xliff:document:1.2">
+    <file source-language="en" target-language="en" datatype="plaintext" original="file.ext">
+        <header>
+            <tool tool-id="symfony" tool-name="Symfony"/>
+        </header>
+        <body>
+            <trans-unit id="994ixRL" resname="new.foo">
+                <source>new.foo</source>
+                <target>newFoo</target>
+            </trans-unit>
+            <trans-unit id="7bRlYkK" resname="note">
+                <source>note</source>
+                <target>NOTE</target>
+            </trans-unit>
+        </body>
+    </file>
+</xliff>
+XLIFF
+            , file_get_contents($filenameEn));
+        $this->assertXmlStringEqualsXmlString(<<<XLIFF
+<?xml version="1.0"?>
+<xliff version="1.2" xmlns="urn:oasis:names:tc:xliff:document:1.2">
+    <file source-language="en" target-language="fr" datatype="plaintext" original="file.ext">
+        <header>
+            <tool tool-id="symfony" tool-name="Symfony"/>
+        </header>
+        <body>
+            <trans-unit id="994ixRL" resname="new.foo">
+                <source>new.foo</source>
+                <target>nouveauFoo</target>
+            </trans-unit>
+            <trans-unit id="7bRlYkK" resname="note">
+                <source>note</source>
+                <target>NOTE</target>
+            </trans-unit>
+        </body>
+    </file>
+</xliff>
+XLIFF
+            , file_get_contents($filenameFr));
+    }
+
+    public function testPullNewXlf20Messages()
+    {
+        $arrayLoader = new ArrayLoader();
+        $filenameEn = $this->createFile(['note' => 'NOTE'], 'en', 'messages.%locale%.xlf', 'xlf20');
+        $filenameFr = $this->createFile(['note' => 'NOTE'], 'fr', 'messages.%locale%.xlf', 'xlf20');
+        $locales = ['en', 'fr'];
+        $domains = ['messages'];
+
+        $providerReadTranslatorBag = new TranslatorBag();
+        $providerReadTranslatorBag->addCatalogue($arrayLoader->load([
+            'note' => 'NOTE',
+            'new.foo' => 'newFoo',
+        ], 'en'));
+        $providerReadTranslatorBag->addCatalogue($arrayLoader->load([
+            'note' => 'NOTE',
+            'new.foo' => 'nouveauFoo',
+        ], 'fr'));
+
+        $provider = $this->createMock(ProviderInterface::class);
+        $provider->expects($this->once())
+            ->method('read')
+            ->with($domains, $locales)
+            ->willReturn($providerReadTranslatorBag);
+
+        $provider->expects($this->once())
+            ->method('__toString')
+            ->willReturn('null://default');
+
+        $tester = $this->createCommandTester($provider, $locales, $domains);
+        $tester->execute(['--locales' => ['en', 'fr'], '--domains' => ['messages'], '--format' => 'xlf20']);
+
+        $this->assertStringContainsString('[OK] New translations from "null" has been written locally (for "en, fr" locale(s), and "messages" domain(s)).', trim($tester->getDisplay()));
+        $this->assertXmlStringEqualsXmlString(<<<XLIFF
+<?xml version="1.0" encoding="utf-8"?>
+<xliff xmlns="urn:oasis:names:tc:xliff:document:2.0" version="2.0" srcLang="en" trgLang="en">
+  <file id="messages.en">
+    <unit id="994ixRL" name="new.foo">
+      <segment>
+        <source>new.foo</source>
+        <target>newFoo</target>
+      </segment>
+    </unit>
+    <unit id="7bRlYkK" name="note">
+      <segment>
+        <source>note</source>
+        <target>NOTE</target>
+      </segment>
+    </unit>
+  </file>
+</xliff>
+XLIFF
+            , file_get_contents($filenameEn));
+        $this->assertXmlStringEqualsXmlString(<<<XLIFF
+<?xml version="1.0" encoding="utf-8"?>
+<xliff xmlns="urn:oasis:names:tc:xliff:document:2.0" version="2.0" srcLang="en" trgLang="fr">
+  <file id="messages.fr">
+    <unit id="994ixRL" name="new.foo">
+      <segment>
+        <source>new.foo</source>
+        <target>nouveauFoo</target>
+      </segment>
+    </unit>
+    <unit id="7bRlYkK" name="note">
+      <segment>
+        <source>note</source>
+        <target>NOTE</target>
+      </segment>
+    </unit>
+  </file>
+</xliff>
+XLIFF
+            , file_get_contents($filenameFr));
+    }
+
+    public function testPullForceMessages()
+    {
+        $arrayLoader = new ArrayLoader();
+        $filenameEn = $this->createFile();
+        $filenameFr = $this->createFile(['note' => 'NOTE'], 'fr');
+        $locales = ['en', 'fr'];
+        $domains = ['messages'];
+
+        $providerReadTranslatorBag = new TranslatorBag();
+        $providerReadTranslatorBag->addCatalogue($arrayLoader->load([
+            'note' => 'UPDATED NOTE',
+            'new.foo' => 'newFoo',
+        ], 'en'));
+        $providerReadTranslatorBag->addCatalogue($arrayLoader->load([
+            'note' => 'NOTE MISE À JOUR',
+            'new.foo' => 'nouveauFoo',
+        ], 'fr'));
+
+        $provider = $this->createMock(ProviderInterface::class);
+        $provider->expects($this->once())
+            ->method('read')
+            ->with($domains, $locales)
+            ->willReturn($providerReadTranslatorBag);
+
+        $provider->expects($this->once())
+            ->method('__toString')
+            ->willReturn('null://default');
+
+        $tester = $this->createCommandTester($provider, $locales, $domains);
+        $tester->execute(['--locales' => ['en', 'fr'], '--domains' => ['messages'], '--force' => true]);
+
+        $this->assertStringContainsString('[OK] Local translations has been updated from "null" (for "en, fr" locale(s), and "messages" domain(s)).', trim($tester->getDisplay()));
+        $this->assertXmlStringEqualsXmlString(<<<XLIFF
+<?xml version="1.0"?>
+<xliff version="1.2" xmlns="urn:oasis:names:tc:xliff:document:1.2">
+    <file source-language="en" target-language="en" datatype="plaintext" original="file.ext">
+        <header>
+            <tool tool-id="symfony" tool-name="Symfony"/>
+        </header>
+        <body>
+            <trans-unit id="7bRlYkK" resname="note">
+                <source>note</source>
+                <target>UPDATED NOTE</target>
+            </trans-unit>
+            <trans-unit id="994ixRL" resname="new.foo">
+                <source>new.foo</source>
+                <target>newFoo</target>
+            </trans-unit>
+        </body>
+    </file>
+</xliff>
+XLIFF
+            , file_get_contents($filenameEn));
+        $this->assertXmlStringEqualsXmlString(<<<XLIFF
+<?xml version="1.0"?>
+<xliff version="1.2" xmlns="urn:oasis:names:tc:xliff:document:1.2">
+    <file source-language="en" target-language="fr" datatype="plaintext" original="file.ext">
+        <header>
+            <tool tool-id="symfony" tool-name="Symfony"/>
+        </header>
+        <body>
+            <trans-unit id="7bRlYkK" resname="note">
+                <source>note</source>
+                <target>NOTE MISE À JOUR</target>
+            </trans-unit>
+            <trans-unit id="994ixRL" resname="new.foo">
+                <source>new.foo</source>
+                <target>nouveauFoo</target>
+            </trans-unit>
+        </body>
+    </file>
+</xliff>
+XLIFF
+            , file_get_contents($filenameFr));
+    }
+
+    /**
+     * @requires extension intl
+     */
+    public function testPullForceIntlIcuMessages()
+    {
+        $arrayLoader = new ArrayLoader();
+        $filenameEn = $this->createFile(['note' => 'NOTE'], 'en', 'messages+intl-icu.%locale%.xlf');
+        $filenameFr = $this->createFile(['note' => 'NOTE'], 'fr', 'messages+intl-icu.%locale%.xlf');
+
+        $locales = ['en', 'fr'];
+        $domains = ['messages'];
+
+        $providerReadTranslatorBag = new TranslatorBag();
+        $providerReadTranslatorBag->addCatalogue($arrayLoader->load([
+            'note' => 'UPDATED NOTE',
+            'new.foo' => 'newFoo',
+        ], 'en'));
+        $providerReadTranslatorBag->addCatalogue($arrayLoader->load([
+            'note' => 'NOTE MISE À JOUR',
+            'new.foo' => 'nouveauFoo',
+        ], 'fr'));
+
+        $provider = $this->createMock(ProviderInterface::class);
+        $provider->expects($this->once())
+            ->method('read')
+            ->with($domains, $locales)
+            ->willReturn($providerReadTranslatorBag);
+
+        $provider->expects($this->once())
+            ->method('__toString')
+            ->willReturn('null://default');
+
+        $tester = $this->createCommandTester($provider, $locales, $domains);
+        $tester->execute(['--locales' => ['en', 'fr'], '--domains' => ['messages'], '--force' => true, '--intl-icu' => true]);
+
+        $this->assertStringContainsString('[OK] Local translations has been updated from "null" (for "en, fr" locale(s), and "messages" domain(s)).', trim($tester->getDisplay()));
+        $this->assertXmlStringEqualsXmlString(<<<XLIFF
+<?xml version="1.0"?>
+<xliff version="1.2" xmlns="urn:oasis:names:tc:xliff:document:1.2">
+    <file source-language="en" target-language="en" datatype="plaintext" original="file.ext">
+        <header>
+            <tool tool-id="symfony" tool-name="Symfony"/>
+        </header>
+        <body>
+            <trans-unit id="7bRlYkK" resname="note">
+                <source>note</source>
+                <target>UPDATED NOTE</target>
+            </trans-unit>
+            <trans-unit id="994ixRL" resname="new.foo">
+                <source>new.foo</source>
+                <target>newFoo</target>
+            </trans-unit>
+        </body>
+    </file>
+</xliff>
+XLIFF
+            , file_get_contents($filenameEn));
+        $this->assertXmlStringEqualsXmlString(<<<XLIFF
+<?xml version="1.0"?>
+<xliff version="1.2" xmlns="urn:oasis:names:tc:xliff:document:1.2">
+    <file source-language="en" target-language="fr" datatype="plaintext" original="file.ext">
+        <header>
+            <tool tool-id="symfony" tool-name="Symfony"/>
+        </header>
+        <body>
+            <trans-unit id="7bRlYkK" resname="note">
+                <source>note</source>
+                <target>NOTE MISE À JOUR</target>
+            </trans-unit>
+            <trans-unit id="994ixRL" resname="new.foo">
+                <source>new.foo</source>
+                <target>nouveauFoo</target>
+            </trans-unit>
+        </body>
+    </file>
+</xliff>
+XLIFF
+            , file_get_contents($filenameFr));
+    }
+
+    private function createCommandTester(ProviderInterface $provider, array $locales = ['en'], array $domains = ['messages']): CommandTester
+    {
+        $writer = new TranslationWriter();
+        $writer->addDumper('xlf', new XliffFileDumper());
+
+        $reader = new TranslationReader();
+        $reader->addLoader('xlf', new XliffFileLoader());
+
+        $command = new TranslationPullCommand(
+            $this->getProviderCollection($provider, $locales, $domains),
+            $writer,
+            $reader,
+            'en',
+            [$this->translationAppDir.'/translations']
+        );
+        $application = new Application();
+        $application->add($command);
+
+        return new CommandTester($application->find('translation:pull'));
+    }
+}
diff --git a/src/Symfony/Component/Translation/Tests/Command/TranslationPushCommandTest.php b/src/Symfony/Component/Translation/Tests/Command/TranslationPushCommandTest.php
new file mode 100644
index 0000000000..bcb8514598
--- /dev/null
+++ b/src/Symfony/Component/Translation/Tests/Command/TranslationPushCommandTest.php
@@ -0,0 +1,253 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Bundle\FrameworkBundle\Tests\Command;
+
+use Symfony\Component\Console\Application;
+use Symfony\Component\Console\Tester\CommandTester;
+use Symfony\Component\Translation\Command\TranslationPushCommand;
+use Symfony\Component\Translation\Loader\ArrayLoader;
+use Symfony\Component\Translation\Loader\XliffFileLoader;
+use Symfony\Component\Translation\Provider\ProviderInterface;
+use Symfony\Component\Translation\Reader\TranslationReader;
+use Symfony\Component\Translation\Tests\Command\TranslationProviderTestCase;
+use Symfony\Component\Translation\TranslatorBag;
+
+/**
+ * @author Mathieu Santostefano <msantostefano@protonmail.com>
+ */
+class TranslationPushCommandTest extends TranslationProviderTestCase
+{
+    public function testPushNewMessages()
+    {
+        $arrayLoader = new ArrayLoader();
+        $xliffLoader = new XliffFileLoader();
+        $locales = ['en', 'fr'];
+        $domains = ['messages'];
+
+        // Simulate existing messages on Provider
+        $providerReadTranslatorBag = new TranslatorBag();
+        $providerReadTranslatorBag->addCatalogue($arrayLoader->load(['note' => 'NOTE'], 'en'));
+        $providerReadTranslatorBag->addCatalogue($arrayLoader->load(['note' => 'NOTE'], 'fr'));
+
+        $provider = $this->createMock(ProviderInterface::class);
+        $provider->expects($this->once())
+            ->method('read')
+            ->with($domains, $locales)
+            ->willReturn($providerReadTranslatorBag);
+
+        // Create local files, with a new message
+        $filenameEn = $this->createFile([
+            'note' => 'NOTE',
+            'new.foo' => 'newFoo',
+        ]);
+        $filenameFr = $this->createFile([
+            'note' => 'NOTE',
+            'new.foo' => 'nouveauFoo',
+        ], 'fr');
+        $localTranslatorBag = new TranslatorBag();
+        $localTranslatorBag->addCatalogue($xliffLoader->load($filenameEn, 'en'));
+        $localTranslatorBag->addCatalogue($xliffLoader->load($filenameFr, 'fr'));
+
+        $provider->expects($this->once())
+            ->method('write')
+            ->with($localTranslatorBag->diff($providerReadTranslatorBag));
+
+        $provider->expects($this->once())
+            ->method('__toString')
+            ->willReturn('null://default');
+
+        $tester = $this->createCommandTester($provider, $locales, $domains);
+
+        $tester->execute(['--locales' => ['en', 'fr'], '--domains' => ['messages']]);
+
+        $this->assertStringContainsString('[OK] New local translations has been sent to "null" (for "en, fr" locale(s), and "messages" domain(s)).', trim($tester->getDisplay()));
+    }
+
+    public function testPushForceMessages()
+    {
+        $xliffLoader = new XliffFileLoader();
+        $filenameEn = $this->createFile([
+            'note' => 'NOTE UPDATED',
+            'new.foo' => 'newFoo',
+        ]);
+        $filenameFr = $this->createFile([
+            'note' => 'NOTE MISE À JOUR',
+            'new.foo' => 'nouveauFoo',
+        ], 'fr');
+        $locales = ['en', 'fr'];
+        $domains = ['messages'];
+
+        $provider = $this->createMock(ProviderInterface::class);
+
+        $localTranslatorBag = new TranslatorBag();
+        $localTranslatorBag->addCatalogue($xliffLoader->load($filenameEn, 'en'));
+        $localTranslatorBag->addCatalogue($xliffLoader->load($filenameFr, 'fr'));
+
+        $provider->expects($this->once())
+            ->method('write')
+            ->with($localTranslatorBag);
+
+        $provider->expects($this->once())
+            ->method('__toString')
+            ->willReturn('null://default');
+
+        $tester = $this->createCommandTester($provider, $locales, $domains);
+
+        $tester->execute(['--locales' => ['en', 'fr'], '--domains' => ['messages'], '--force' => true]);
+
+        $this->assertStringContainsString('[OK] All local translations has been sent to "null" (for "en, fr" locale(s), and "messages" domain(s)).', trim($tester->getDisplay()));
+    }
+
+    public function testDeleteMissingMessages()
+    {
+        $xliffLoader = new XliffFileLoader();
+        $arrayLoader = new ArrayLoader();
+        $locales = ['en', 'fr'];
+        $domains = ['messages'];
+
+        // Simulate existing messages on Provider.
+        $providerReadTranslatorBag = new TranslatorBag();
+        $providerReadTranslatorBag->addCatalogue($arrayLoader->load([
+            'note' => 'NOTE',
+            'obsolete.foo' => 'obsoleteFoo',
+        ], 'en'));
+        $providerReadTranslatorBag->addCatalogue($arrayLoader->load([
+            'note' => 'NOTE',
+            'obsolete.foo' => 'obsolèteFoo',
+        ], 'fr'));
+
+        $provider = $this->createMock(ProviderInterface::class);
+        $provider->expects($this->any())
+            ->method('read')
+            ->with($domains, $locales)
+            ->willReturn($providerReadTranslatorBag);
+
+        // Create local bag, with a missing message.
+        $localTranslatorBag = new TranslatorBag();
+        $localTranslatorBag->addCatalogue($xliffLoader->load($this->createFile(), 'en'));
+        $localTranslatorBag->addCatalogue($xliffLoader->load($this->createFile(['note' => 'NOTE'], 'fr'), 'fr'));
+
+        $missingTranslatorBag = $providerReadTranslatorBag->diff($localTranslatorBag);
+
+        $provider->expects($this->once())
+            ->method('delete')
+            ->with($missingTranslatorBag);
+
+        // Read provider translations again, after missing translations deletion,
+        // to avoid push freshly deleted translations.
+        $providerReadTranslatorBag = new TranslatorBag();
+        $providerReadTranslatorBag->addCatalogue($arrayLoader->load(['note' => 'NOTE'], 'en'));
+        $providerReadTranslatorBag->addCatalogue($arrayLoader->load(['note' => 'NOTE'], 'fr'));
+
+        $provider->expects($this->any())
+            ->method('read')
+            ->with($domains, $locales)
+            ->willReturn($providerReadTranslatorBag);
+
+        $provider->expects($this->once())
+            ->method('write')
+            ->with($localTranslatorBag->diff($providerReadTranslatorBag));
+
+        $provider->expects($this->exactly(2))
+            ->method('__toString')
+            ->willReturn('null://default');
+
+        $tester = $this->createCommandTester($provider, $locales, $domains);
+
+        $tester->execute(['--locales' => ['en', 'fr'], '--domains' => ['messages'], '--delete-missing' => true]);
+
+        $this->assertStringContainsString('[OK] Missing translations on "null" has been deleted (for "en, fr" locale(s), and "messages" domain(s)).', trim($tester->getDisplay()));
+        $this->assertStringContainsString('[OK] New local translations has been sent to "null" (for "en, fr" locale(s), and "messages" domain(s)).', trim($tester->getDisplay()));
+    }
+
+    public function testPushForceAndDeleteMissingMessages()
+    {
+        $xliffLoader = new XliffFileLoader();
+        $arrayLoader = new ArrayLoader();
+        $locales = ['en', 'fr'];
+        $domains = ['messages'];
+
+        // Simulate existing messages on Provider.
+        $providerReadTranslatorBag = new TranslatorBag();
+        $providerReadTranslatorBag->addCatalogue($arrayLoader->load([
+            'note' => 'NOTE',
+            'obsolete.foo' => 'obsoleteFoo',
+        ], 'en'));
+        $providerReadTranslatorBag->addCatalogue($arrayLoader->load([
+            'note' => 'NOTE',
+            'obsolete.foo' => 'obsolèteFoo',
+        ], 'fr'));
+
+        $provider = $this->createMock(ProviderInterface::class);
+        $provider->expects($this->any())
+            ->method('read')
+            ->with($domains, $locales)
+            ->willReturn($providerReadTranslatorBag);
+
+        // Create local bag, with a missing message, an updated one and a new one.
+        $localTranslatorBag = new TranslatorBag();
+        $localTranslatorBag->addCatalogue($xliffLoader->load($this->createFile(['note' => 'NOTE UPDATED', 'note2' => 'NOTE 2']), 'en'));
+        $localTranslatorBag->addCatalogue($xliffLoader->load($this->createFile(['note' => 'NOTE MISE À JOUR', 'note2' => 'NOTE 2'], 'fr'), 'fr'));
+
+        $missingTranslatorBag = $providerReadTranslatorBag->diff($localTranslatorBag);
+
+        $provider->expects($this->once())
+            ->method('delete')
+            ->with($missingTranslatorBag);
+
+        // Read provider translations again, after missing translations deletion,
+        // to avoid push freshly deleted translations.
+        $providerReadTranslatorBag = new TranslatorBag();
+        $providerReadTranslatorBag->addCatalogue($arrayLoader->load(['note' => 'NOTE'], 'en'));
+        $providerReadTranslatorBag->addCatalogue($arrayLoader->load(['note' => 'NOTE'], 'fr'));
+
+        $provider->expects($this->any())
+            ->method('read')
+            ->with($domains, $locales)
+            ->willReturn($providerReadTranslatorBag);
+
+        $translationBagToWrite = $localTranslatorBag->diff($providerReadTranslatorBag);
+        $translationBagToWrite->addBag($localTranslatorBag->intersect($providerReadTranslatorBag));
+
+        $provider->expects($this->once())
+            ->method('write')
+            ->with($translationBagToWrite);
+
+        $provider->expects($this->exactly(2))
+            ->method('__toString')
+            ->willReturn('null://default');
+
+        $tester = $this->createCommandTester($provider, $locales, $domains);
+
+        $tester->execute(['--locales' => ['en', 'fr'], '--domains' => ['messages'], '--force' => true, '--delete-missing' => true]);
+
+        $this->assertStringContainsString('[OK] Missing translations on "null" has been deleted (for "en, fr" locale(s), and "messages" domain(s)).', trim($tester->getDisplay()));
+        $this->assertStringContainsString('[OK] All local translations has been sent to "null" (for "en, fr" locale(s), and "messages" domain(s)).', trim($tester->getDisplay()));
+    }
+
+    private function createCommandTester(ProviderInterface $provider, array $locales = ['en'], array $domains = ['messages']): CommandTester
+    {
+        $reader = new TranslationReader();
+        $reader->addLoader('xlf', new XliffFileLoader());
+
+        $command = new TranslationPushCommand(
+            $this->getProviderCollection($provider, $locales, $domains),
+            $reader,
+            [$this->translationAppDir.'/translations'],
+            $locales
+        );
+        $application = new Application();
+        $application->add($command);
+
+        return new CommandTester($application->find('translation:push'));
+    }
+}
diff --git a/src/Symfony/Component/Translation/Tests/DependencyInjection/TranslationPathsPassTest.php b/src/Symfony/Component/Translation/Tests/DependencyInjection/TranslationPathsPassTest.php
index 42ab398dff..ec803eb5a1 100644
--- a/src/Symfony/Component/Translation/Tests/DependencyInjection/TranslationPathsPassTest.php
+++ b/src/Symfony/Component/Translation/Tests/DependencyInjection/TranslationPathsPassTest.php
@@ -72,7 +72,7 @@ class TranslationPathsPassTest extends TestCase
             ->setArguments([new Reference('.service_locator.bar')])
         ;
 
-        $pass = new TranslatorPathsPass('translator', 'console.command.translation_debug', 'console.command.translation_update', 'argument_resolver.service');
+        $pass = new TranslatorPathsPass();
         $pass->process($container);
 
         $expectedPaths = [
diff --git a/src/Symfony/Component/Translation/Tests/Loader/XliffFileLoaderTest.php b/src/Symfony/Component/Translation/Tests/Loader/XliffFileLoaderTest.php
index 9836ff1cb7..6cfa16de04 100644
--- a/src/Symfony/Component/Translation/Tests/Loader/XliffFileLoaderTest.php
+++ b/src/Symfony/Component/Translation/Tests/Loader/XliffFileLoaderTest.php
@@ -19,7 +19,7 @@ use Symfony\Component\Translation\Loader\XliffFileLoader;
 
 class XliffFileLoaderTest extends TestCase
 {
-    public function testLoad()
+    public function testLoadFile()
     {
         $loader = new XliffFileLoader();
         $resource = __DIR__.'/../fixtures/resources.xlf';
@@ -31,6 +31,42 @@ class XliffFileLoaderTest extends TestCase
         $this->assertContainsOnly('string', $catalogue->all('domain1'));
     }
 
+    public function testLoadRawXliff()
+    {
+        $loader = new XliffFileLoader();
+        $resource = <<<XLIFF
+<?xml version="1.0" encoding="utf-8"?>
+<xliff xmlns="urn:oasis:names:tc:xliff:document:1.2" version="1.2">
+  <file source-language="en" datatype="plaintext" original="file.ext">
+    <body>
+      <trans-unit id="1">
+        <source>foo</source>
+        <target>bar</target>
+      </trans-unit>
+      <trans-unit id="2">
+        <source>extra</source>
+      </trans-unit>
+      <trans-unit id="3">
+        <source>key</source>
+        <target></target>
+      </trans-unit>
+      <trans-unit id="4">
+        <source>test</source>
+        <target>with</target>
+        <note>note</note>
+      </trans-unit>
+    </body>
+  </file>
+</xliff>
+XLIFF;
+
+        $catalogue = $loader->load($resource, 'en', 'domain1');
+
+        $this->assertEquals('en', $catalogue->getLocale());
+        $this->assertSame([], libxml_get_errors());
+        $this->assertContainsOnly('string', $catalogue->all('domain1'));
+    }
+
     public function testLoadWithInternalErrorsEnabled()
     {
         $internalErrors = libxml_use_internal_errors(true);
diff --git a/src/Symfony/Component/Translation/Tests/Provider/DsnTest.php b/src/Symfony/Component/Translation/Tests/Provider/DsnTest.php
new file mode 100644
index 0000000000..e6cf8a388d
--- /dev/null
+++ b/src/Symfony/Component/Translation/Tests/Provider/DsnTest.php
@@ -0,0 +1,108 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Translation\Tests\Provider;
+
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\Translation\Exception\InvalidArgumentException;
+use Symfony\Component\Translation\Provider\Dsn;
+
+class DsnTest extends TestCase
+{
+    /**
+     * @dataProvider fromStringProvider
+     */
+    public function testFromString(string $string, Dsn $expectedDsn): void
+    {
+        $actualDsn = Dsn::fromString($string);
+
+        $this->assertSame($expectedDsn->getScheme(), $actualDsn->getScheme());
+        $this->assertSame($expectedDsn->getHost(), $actualDsn->getHost());
+        $this->assertSame($expectedDsn->getPort(), $actualDsn->getPort());
+        $this->assertSame($expectedDsn->getUser(), $actualDsn->getUser());
+        $this->assertSame($expectedDsn->getPassword(), $actualDsn->getPassword());
+        $this->assertSame($expectedDsn->getPath(), $actualDsn->getPath());
+        $this->assertSame($expectedDsn->getOption('from'), $actualDsn->getOption('from'));
+
+        $this->assertSame($string, $actualDsn->getOriginalDsn());
+    }
+
+    public function fromStringProvider(): iterable
+    {
+        yield 'simple dsn' => [
+            'scheme://localhost',
+            new Dsn('scheme', 'localhost', null, null, null, [], null),
+        ];
+
+        yield 'dsn with user and pass' => [
+            'scheme://u$er:pa$s@localhost',
+            new Dsn('scheme', 'localhost', 'u$er', 'pa$s', null, [], null),
+        ];
+
+        yield 'dsn with user and pass and custom port' => [
+            'scheme://u$er:pa$s@localhost:8000',
+            new Dsn('scheme', 'localhost', 'u$er', 'pa$s', '8000', [], null),
+        ];
+
+        yield 'dsn with user and pass, custom port and custom path' => [
+            'scheme://u$er:pa$s@localhost:8000/channel',
+            new Dsn('scheme', 'localhost', 'u$er', 'pa$s', '8000', [], '/channel'),
+        ];
+
+        yield 'dsn with user and pass, custom port, custom path and custom options' => [
+            'scheme://u$er:pa$s@localhost:8000/channel?from=FROM',
+            new Dsn('scheme', 'localhost', 'u$er', 'pa$s', '8000', ['from' => 'FROM'], '/channel'),
+        ];
+
+        yield 'dsn with user and pass that contains an urlencoded character' => [
+            'scheme://u$er:p%2Fa$s@localhost',
+            new Dsn('scheme', 'localhost', 'u$er', 'p/a$s'),
+        ];
+    }
+
+    /**
+     * @dataProvider invalidDsnProvider
+     */
+    public function testInvalidDsn(string $dsn, string $exceptionMessage): void
+    {
+        $this->expectException(InvalidArgumentException::class);
+        $this->expectExceptionMessage($exceptionMessage);
+        Dsn::fromString($dsn);
+    }
+
+    public function invalidDsnProvider(): iterable
+    {
+        yield [
+            'some://',
+            'The "some://" translation provider DSN is invalid.',
+        ];
+
+        yield [
+            '//loco',
+            'The "//loco" translation provider DSN must contain a scheme.',
+        ];
+
+        yield [
+            'file:///some/path',
+            'The "file:///some/path" translation provider DSN must contain a host (use "default" by default).',
+        ];
+    }
+
+    public function testGetOption(): void
+    {
+        $options = ['with_value' => 'some value', 'nullable' => null];
+        $dsn = new Dsn('scheme', 'localhost', 'u$er', 'pa$s', '8000', $options, '/channel');
+
+        $this->assertSame('some value', $dsn->getOption('with_value'));
+        $this->assertSame('default', $dsn->getOption('nullable', 'default'));
+        $this->assertSame('default', $dsn->getOption('not_existent_property', 'default'));
+    }
+}
diff --git a/src/Symfony/Component/Translation/Tests/Provider/NullProviderFactoryTest.php b/src/Symfony/Component/Translation/Tests/Provider/NullProviderFactoryTest.php
new file mode 100644
index 0000000000..6f35ebad66
--- /dev/null
+++ b/src/Symfony/Component/Translation/Tests/Provider/NullProviderFactoryTest.php
@@ -0,0 +1,38 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Translation\Tests\Provider;
+
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\Translation\Exception\UnsupportedSchemeException;
+use Symfony\Component\Translation\Provider\Dsn;
+use Symfony\Component\Translation\Provider\NullProvider;
+use Symfony\Component\Translation\Provider\NullProviderFactory;
+
+/**
+ * @author Mathieu Santostefano <msantostefano@protonmail.com>
+ *
+ * @experimental in 5.3
+ */
+class NullProviderFactoryTest extends TestCase
+{
+    public function testCreateThrowsUnsupportedSchemeException()
+    {
+        $this->expectException(UnsupportedSchemeException::class);
+
+        (new NullProviderFactory())->create(new Dsn('foo', ''));
+    }
+
+    public function testCreate()
+    {
+        $this->assertInstanceOf(NullProvider::class, (new NullProviderFactory())->create(new Dsn('null', '')));
+    }
+}
diff --git a/src/Symfony/Component/Translation/Tests/ProviderFactoryTestCase.php b/src/Symfony/Component/Translation/Tests/ProviderFactoryTestCase.php
new file mode 100644
index 0000000000..8bb2250734
--- /dev/null
+++ b/src/Symfony/Component/Translation/Tests/ProviderFactoryTestCase.php
@@ -0,0 +1,145 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Translation\Tests;
+
+use PHPUnit\Framework\TestCase;
+use Psr\Log\LoggerInterface;
+use Symfony\Component\HttpClient\MockHttpClient;
+use Symfony\Component\Translation\Dumper\XliffFileDumper;
+use Symfony\Component\Translation\Exception\IncompleteDsnException;
+use Symfony\Component\Translation\Exception\UnsupportedSchemeException;
+use Symfony\Component\Translation\Loader\LoaderInterface;
+use Symfony\Component\Translation\Provider\Dsn;
+use Symfony\Component\Translation\Provider\ProviderFactoryInterface;
+use Symfony\Contracts\HttpClient\HttpClientInterface;
+
+/**
+ * A test case to ease testing a translation provider factory.
+ *
+ * @author Mathieu Santostefano <msantostefano@protonmail.com>
+ */
+abstract class ProviderFactoryTestCase extends TestCase
+{
+    protected $client;
+    protected $logger;
+    protected $defaultLocale;
+    protected $loader;
+    protected $xliffFileDumper;
+
+    abstract public function createFactory(): ProviderFactoryInterface;
+
+    /**
+     * @return iterable<array{0: bool, 1: string}>
+     */
+    abstract public function supportsProvider(): iterable;
+
+    /**
+     * @return iterable<array{0: string, 1: string, 2: TransportInterface}>
+     */
+    abstract public function createProvider(): iterable;
+
+    /**
+     * @return iterable<array{0: string, 1: string|null}>
+     */
+    public function unsupportedSchemeProvider(): iterable
+    {
+        return [];
+    }
+
+    /**
+     * @return iterable<array{0: string, 1: string|null}>
+     */
+    public function incompleteDsnProvider(): iterable
+    {
+        return [];
+    }
+
+    /**
+     * @dataProvider supportsProvider
+     */
+    public function testSupports(bool $expected, string $dsn)
+    {
+        $factory = $this->createFactory();
+
+        $this->assertSame($expected, $factory->supports(Dsn::fromString($dsn)));
+    }
+
+    /**
+     * @dataProvider unsupportedSchemeProvider
+     */
+    public function testUnsupportedSchemeException(string $dsn, string $message = null)
+    {
+        $factory = $this->createFactory();
+
+        $dsn = Dsn::fromString($dsn);
+
+        $this->expectException(UnsupportedSchemeException::class);
+        if (null !== $message) {
+            $this->expectExceptionMessage($message);
+        }
+
+        $factory->create($dsn);
+    }
+
+    /**
+     * @dataProvider createProvider
+     */
+    public function testCreate(string $expected, string $dsn)
+    {
+        $factory = $this->createFactory();
+        $provider = $factory->create(Dsn::fromString($dsn));
+
+        $this->assertSame($expected, (string) $provider);
+    }
+
+    /**
+     * @dataProvider incompleteDsnProvider
+     */
+    public function testIncompleteDsnException(string $dsn, string $message = null)
+    {
+        $factory = $this->createFactory();
+
+        $dsn = Dsn::fromString($dsn);
+
+        $this->expectException(IncompleteDsnException::class);
+        if (null !== $message) {
+            $this->expectExceptionMessage($message);
+        }
+
+        $factory->create($dsn);
+    }
+
+    protected function getClient(): HttpClientInterface
+    {
+        return $this->client ?? $this->client = new MockHttpClient();
+    }
+
+    protected function getLogger(): LoggerInterface
+    {
+        return $this->logger ?? $this->logger = $this->createMock(LoggerInterface::class);
+    }
+
+    protected function getDefaultLocale(): string
+    {
+        return $this->defaultLocale ?? $this->defaultLocale = 'en';
+    }
+
+    protected function getLoader(): LoaderInterface
+    {
+        return $this->loader ?? $this->loader = $this->createMock(LoaderInterface::class);
+    }
+
+    protected function getXliffFileDumper(): XliffFileDumper
+    {
+        return $this->xliffFileDumper ?? $this->xliffFileDumper = $this->createMock(XliffFileDumper::class);
+    }
+}
diff --git a/src/Symfony/Component/Translation/Tests/ProviderTestCase.php b/src/Symfony/Component/Translation/Tests/ProviderTestCase.php
new file mode 100644
index 0000000000..fee89a2d5f
--- /dev/null
+++ b/src/Symfony/Component/Translation/Tests/ProviderTestCase.php
@@ -0,0 +1,75 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Translation\Tests;
+
+use PHPUnit\Framework\TestCase;
+use Psr\Log\LoggerInterface;
+use Symfony\Component\HttpClient\MockHttpClient;
+use Symfony\Component\Translation\Bridge\Loco\Provider\LocoProvider;
+use Symfony\Component\Translation\Dumper\XliffFileDumper;
+use Symfony\Component\Translation\Loader\LoaderInterface;
+use Symfony\Component\Translation\Provider\ProviderInterface;
+use Symfony\Contracts\HttpClient\HttpClientInterface;
+
+/**
+ * A test case to ease testing a translation provider.
+ *
+ * @author Mathieu Santostefano <msantostefano@protonmail.com>
+ */
+abstract class ProviderTestCase extends TestCase
+{
+    protected $client;
+    protected $logger;
+    protected $defaultLocale;
+    protected $loader;
+    protected $xliffFileDumper;
+
+    abstract public function createProvider(HttpClientInterface $client, LoaderInterface $loader, LoggerInterface $logger, string $defaultLocale, string $endpoint): ProviderInterface;
+
+    /**
+     * @return iterable<array{0: string, 1: ProviderInterface}>
+     */
+    abstract public function toStringProvider(): iterable;
+
+    /**
+     * @dataProvider toStringProvider
+     */
+    public function testToString(LocoProvider $provider, string $expected)
+    {
+        $this->assertSame($expected, (string) $provider);
+    }
+
+    protected function getClient(): MockHttpClient
+    {
+        return $this->client ?? $this->client = new MockHttpClient();
+    }
+
+    protected function getLoader(): LoaderInterface
+    {
+        return $this->loader ?? $this->loader = $this->createMock(LoaderInterface::class);
+    }
+
+    protected function getLogger(): LoggerInterface
+    {
+        return $this->logger ?? $this->logger = $this->createMock(LoggerInterface::class);
+    }
+
+    protected function getDefaultLocale(): string
+    {
+        return $this->defaultLocale ?? $this->defaultLocale = 'en';
+    }
+
+    protected function getXliffFileDumper(): XliffFileDumper
+    {
+        return $this->xliffFileDumper ?? $this->xliffFileDumper = $this->createMock(XliffFileDumper::class);
+    }
+}
diff --git a/src/Symfony/Component/Translation/Tests/TranslatorBagTest.php b/src/Symfony/Component/Translation/Tests/TranslatorBagTest.php
new file mode 100644
index 0000000000..a202bc65ca
--- /dev/null
+++ b/src/Symfony/Component/Translation/Tests/TranslatorBagTest.php
@@ -0,0 +1,100 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Translation\Tests;
+
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\Translation\MessageCatalogue;
+use Symfony\Component\Translation\TranslatorBag;
+
+class TranslatorBagTest extends TestCase
+{
+    public function testAll()
+    {
+        $catalogue = new MessageCatalogue('en', $messages = ['domain1' => ['foo' => 'foo'], 'domain2' => ['bar' => 'bar']]);
+
+        $bag = new TranslatorBag();
+        $bag->addCatalogue($catalogue);
+
+        $this->assertEquals(['en' => $messages], $this->getAllMessagesFromTranslatorBag($bag));
+
+        $messages = ['domain1+intl-icu' => ['foo' => 'bar']] + $messages + [
+                'domain2+intl-icu' => ['bar' => 'foo'],
+                'domain3+intl-icu' => ['biz' => 'biz'],
+            ];
+        $catalogue = new MessageCatalogue('en', $messages);
+
+        $bag = new TranslatorBag();
+        $bag->addCatalogue($catalogue);
+
+        $this->assertEquals([
+            'en' => [
+                'domain1' => ['foo' => 'bar'],
+                'domain2' => ['bar' => 'foo'],
+                'domain3' => ['biz' => 'biz'],
+            ],
+        ], $this->getAllMessagesFromTranslatorBag($bag));
+    }
+
+    public function testDiff()
+    {
+        $catalogueA = new MessageCatalogue('en', ['domain1' => ['foo' => 'foo', 'bar' => 'bar'], 'domain2' => ['baz' => 'baz', 'qux' => 'qux']]);
+
+        $bagA = new TranslatorBag();
+        $bagA->addCatalogue($catalogueA);
+
+        $catalogueB = new MessageCatalogue('en', ['domain1' => ['foo' => 'foo'], 'domain2' => ['baz' => 'baz', 'corge' => 'corge']]);
+
+        $bagB = new TranslatorBag();
+        $bagB->addCatalogue($catalogueB);
+
+        $bagResult = $bagA->diff($bagB);
+
+        $this->assertEquals([
+            'en' => [
+                'domain1' => ['bar' => 'bar'],
+                'domain2' => ['qux' => 'qux'],
+            ],
+        ], $this->getAllMessagesFromTranslatorBag($bagResult));
+    }
+
+    public function testIntersect()
+    {
+        $catalogueA = new MessageCatalogue('en', ['domain1' => ['foo' => 'foo', 'bar' => 'bar'], 'domain2' => ['baz' => 'baz', 'qux' => 'qux']]);
+
+        $bagA = new TranslatorBag();
+        $bagA->addCatalogue($catalogueA);
+
+        $catalogueB = new MessageCatalogue('en', ['domain1' => ['foo' => 'foo', 'baz' => 'baz'], 'domain2' => ['baz' => 'baz', 'corge' => 'corge']]);
+
+        $bagB = new TranslatorBag();
+        $bagB->addCatalogue($catalogueB);
+
+        $bagResult = $bagA->intersect($bagB);
+
+        $this->assertEquals([
+            'en' => [
+                'domain1' => ['bar' => 'bar'],
+                'domain2' => ['qux' => 'qux'],
+            ],
+        ], $this->getAllMessagesFromTranslatorBag($bagResult));
+    }
+
+    private function getAllMessagesFromTranslatorBag(TranslatorBag $translatorBag): array
+    {
+        $allMessages = [];
+        foreach ($translatorBag->getCatalogues() as $catalogue) {
+            $allMessages[$catalogue->getLocale()] = $catalogue->all();
+        }
+
+        return $allMessages;
+    }
+}
diff --git a/src/Symfony/Component/Translation/Translator.php b/src/Symfony/Component/Translation/Translator.php
index e332e13753..b40f13d3de 100644
--- a/src/Symfony/Component/Translation/Translator.php
+++ b/src/Symfony/Component/Translation/Translator.php
@@ -243,6 +243,14 @@ class Translator implements TranslatorInterface, TranslatorBagInterface, LocaleA
         return $this->catalogues[$locale];
     }
 
+    /**
+     * {@inheritdoc}
+     */
+    public function getCatalogues(): array
+    {
+        return array_values($this->catalogues);
+    }
+
     /**
      * Gets the loaders.
      *
diff --git a/src/Symfony/Component/Translation/TranslatorBag.php b/src/Symfony/Component/Translation/TranslatorBag.php
new file mode 100644
index 0000000000..c6555782fd
--- /dev/null
+++ b/src/Symfony/Component/Translation/TranslatorBag.php
@@ -0,0 +1,105 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Translation;
+
+use Symfony\Component\Translation\Catalogue\AbstractOperation;
+use Symfony\Component\Translation\Catalogue\TargetOperation;
+
+final class TranslatorBag implements TranslatorBagInterface
+{
+    /** @var MessageCatalogue[] */
+    private $catalogues = [];
+
+    public function addCatalogue(MessageCatalogue $catalogue): void
+    {
+        if (null !== $existingCatalogue = $this->getCatalogue($catalogue->getLocale())) {
+            $catalogue->addCatalogue($existingCatalogue);
+        }
+
+        $this->catalogues[$catalogue->getLocale()] = $catalogue;
+    }
+
+    public function addBag(TranslatorBagInterface $bag): void
+    {
+        foreach ($bag->getCatalogues() as $catalogue) {
+            $this->addCatalogue($catalogue);
+        }
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getCatalogue(string $locale = null)
+    {
+        if (null === $locale || !isset($this->catalogues[$locale])) {
+            $this->catalogues[$locale] = new MessageCatalogue($locale);
+        }
+
+        return $this->catalogues[$locale];
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getCatalogues(): array
+    {
+        return array_values($this->catalogues);
+    }
+
+    public function diff(TranslatorBagInterface $diffBag): self
+    {
+        $diff = new self();
+
+        foreach ($this->catalogues as $locale => $catalogue) {
+            if (null === $diffCatalogue = $diffBag->getCatalogue($locale)) {
+                $diff->addCatalogue($catalogue);
+
+                continue;
+            }
+
+            $operation = new TargetOperation($diffCatalogue, $catalogue);
+            $operation->moveMessagesToIntlDomainsIfPossible(AbstractOperation::NEW_BATCH);
+            $newCatalogue = new MessageCatalogue($locale);
+
+            foreach ($operation->getDomains() as $domain) {
+                $newCatalogue->add($operation->getNewMessages($domain), $domain);
+            }
+
+            $diff->addCatalogue($newCatalogue);
+        }
+
+        return $diff;
+    }
+
+    public function intersect(TranslatorBagInterface $intersectBag): self
+    {
+        $diff = new self();
+
+        foreach ($this->catalogues as $locale => $catalogue) {
+            if (null === $intersectCatalogue = $intersectBag->getCatalogue($locale)) {
+                continue;
+            }
+
+            $operation = new TargetOperation($catalogue, $intersectCatalogue);
+            $operation->moveMessagesToIntlDomainsIfPossible(AbstractOperation::OBSOLETE_BATCH);
+            $obsoleteCatalogue = new MessageCatalogue($locale);
+
+            foreach ($operation->getDomains() as $domain) {
+                $obsoleteCatalogue->add($operation->getObsoleteMessages($domain), $domain);
+            }
+
+            $diff->addCatalogue($obsoleteCatalogue);
+        }
+
+        return $diff;
+    }
+}
diff --git a/src/Symfony/Component/Translation/TranslatorBagInterface.php b/src/Symfony/Component/Translation/TranslatorBagInterface.php
index e40ca8a23b..4228977352 100644
--- a/src/Symfony/Component/Translation/TranslatorBagInterface.php
+++ b/src/Symfony/Component/Translation/TranslatorBagInterface.php
@@ -16,6 +16,8 @@ use Symfony\Component\Translation\Exception\InvalidArgumentException;
 /**
  * TranslatorBagInterface.
  *
+ * @method MessageCatalogueInterface[] getCatalogues() Returns all catalogues of the instance
+ *
  * @author Abdellatif Ait boudad <a.aitboudad@gmail.com>
  */
 interface TranslatorBagInterface
diff --git a/src/Symfony/Component/Translation/composer.json b/src/Symfony/Component/Translation/composer.json
index 3f2c16d3b6..01c05bd7d8 100644
--- a/src/Symfony/Component/Translation/composer.json
+++ b/src/Symfony/Component/Translation/composer.json
@@ -28,6 +28,7 @@
         "symfony/dependency-injection": "^5.0",
         "symfony/http-kernel": "^5.0",
         "symfony/intl": "^4.4|^5.0",
+        "symfony/polyfill-intl-icu": "^1.21",
         "symfony/service-contracts": "^1.1.2|^2",
         "symfony/yaml": "^4.4|^5.0",
         "symfony/finder": "^4.4|^5.0",