bug #25381 [DI] Add context to service-not-found exceptions thrown by service locators (nicolas-grekas)

This PR was merged into the 3.4 branch. Discussion ---------- [DI] Add context to service-not-found exceptions thrown by service locators | Q | A | ------------- | --- | Branch? | 3.4 | Bug fix? | yes (DX) | New feature? | yes (...) | BC breaks? | no | Deprecations? | no | Tests pass? | yes | Fixed tickets | #25342, #25196 | License | MIT | Doc PR | - Here hopefully is the fully-context aware message you're looking for @weaverryan @curry684. ![image](https://user-images.githubusercontent.com/243674/33726013-1db38a34-db74-11e7-91dd-ca9d53e58891.png) Commits ------- 9512f268f4 [DI] Add context to service-not-found exceptions thrown by service locators
2017-12-11 12:28:19 -08:00 · 2017-12-11 12:28:19 -08:00 · 5b66c269d2
commit 5b66c269d2
parent d21aa19e4d 9512f268f4
6 changed files with 165 additions and 20 deletions
--- a/src/Symfony/Component/DependencyInjection/Compiler/RegisterServiceSubscribersPass.php
+++ b/src/Symfony/Component/DependencyInjection/Compiler/RegisterServiceSubscribersPass.php
@ -94,7 +94,7 @@ class RegisterServiceSubscribersPass extends AbstractRecursivePass
            throw new InvalidArgumentException(sprintf('Service %s not exist in the map returned by "%s::getSubscribedServices()" for service "%s".', $message, $class, $this->currentId));
        }

-        $value->addTag('container.service_subscriber.locator', array('id' => (string) ServiceLocatorTagPass::register($this->container, $subscriberMap)));
+        $value->addTag('container.service_subscriber.locator', array('id' => (string) ServiceLocatorTagPass::register($this->container, $subscriberMap, $this->currentId)));

        return parent::processValue($value);
    }
--- a/src/Symfony/Component/DependencyInjection/Compiler/ServiceLocatorTagPass.php
+++ b/src/Symfony/Component/DependencyInjection/Compiler/ServiceLocatorTagPass.php
@ -72,10 +72,11 @@ final class ServiceLocatorTagPass extends AbstractRecursivePass
    /**
     * @param ContainerBuilder $container
     * @param Reference[]      $refMap
+     * @param string|null      $callerId
     *
     * @return Reference
     */
-    public static function register(ContainerBuilder $container, array $refMap)
+    public static function register(ContainerBuilder $container, array $refMap, $callerId = null)
    {
        foreach ($refMap as $id => $ref) {
            if (!$ref instanceof Reference) {
@ -94,6 +95,18 @@ final class ServiceLocatorTagPass extends AbstractRecursivePass
            $container->setDefinition($id, $locator);
        }

+        if (null !== $callerId) {
+            $locatorId = $id;
+            // Locators are shared when they hold the exact same list of factories;
+            // to have them specialized per consumer service, we use a cloning factory
+            // to derivate customized instances from the prototype one.
+            $container->register($id .= '.'.$callerId, ServiceLocator::class)
+                ->setPublic(false)
+                ->setFactory(array(new Reference($locatorId), 'withContext'))
+                ->addArgument($callerId)
+                ->addArgument(new Reference('service_container'));
+        }
+
        return new Reference($id);
    }
 }
--- a/src/Symfony/Component/DependencyInjection/ServiceLocator.php
+++ b/src/Symfony/Component/DependencyInjection/ServiceLocator.php
@ -22,6 +22,9 @@ use Symfony\Component\DependencyInjection\Exception\ServiceNotFoundException;
 class ServiceLocator implements PsrContainerInterface
 {
    private $factories;
+    private $loading = array();
+    private $externalId;
+    private $container;

    /**
     * @param callable[] $factories
@ -45,18 +48,22 @@ class ServiceLocator implements PsrContainerInterface
    public function get($id)
    {
        if (!isset($this->factories[$id])) {
-            throw new ServiceNotFoundException($id, null, null, array_keys($this->factories));
+            throw new ServiceNotFoundException($id, end($this->loading) ?: null, null, array(), $this->createServiceNotFoundMessage($id));
        }

-        if (true === $factory = $this->factories[$id]) {
-            throw new ServiceCircularReferenceException($id, array($id, $id));
+        if (isset($this->loading[$id])) {
+            $ids = array_values($this->loading);
+            $ids = array_slice($this->loading, array_search($id, $ids));
+            $ids[] = $id;
+
+            throw new ServiceCircularReferenceException($id, $ids);
        }

-        $this->factories[$id] = true;
+        $this->loading[$id] = $id;
        try {
-            return $factory();
+            return $this->factories[$id]();
        } finally {
-            $this->factories[$id] = $factory;
+            unset($this->loading[$id]);
        }
    }

@ -64,4 +71,75 @@ class ServiceLocator implements PsrContainerInterface
    {
        return isset($this->factories[$id]) ? $this->get($id) : null;
    }
+
+    /**
+     * @internal
+     */
+    public function withContext($externalId, Container $container)
+    {
+        $locator = clone $this;
+        $locator->externalId = $externalId;
+        $locator->container = $container;
+
+        return $locator;
+    }
+
+    private function createServiceNotFoundMessage($id)
+    {
+        if ($this->loading) {
+            return sprintf('The service "%s" has a dependency on a non-existent service "%s". This locator %s', end($this->loading), $id, $this->formatAlternatives());
+        }
+
+        $class = debug_backtrace(DEBUG_BACKTRACE_PROVIDE_OBJECT | DEBUG_BACKTRACE_IGNORE_ARGS, 3);
+        $class = isset($class[2]['object']) ? get_class($class[2]['object']) : null;
+        $externalId = $this->externalId ?: $class;
+
+        $msg = sprintf('Service "%s" not found: ', $id);
+
+        if (!$this->container) {
+            $class = null;
+        } elseif ($this->container->has($id) || isset($this->container->getRemovedIds()[$id])) {
+            $msg .= 'even though it exists in the app\'s container, ';
+        } else {
+            try {
+                $this->container->get($id);
+                $class = null;
+            } catch (ServiceNotFoundException $e) {
+                if ($e->getAlternatives()) {
+                    $msg .= sprintf(' did you mean %s? Anyway, ', $this->formatAlternatives($e->getAlternatives(), 'or'));
+                } else {
+                    $class = null;
+                }
+            }
+        }
+        if ($externalId) {
+            $msg .= sprintf('the container inside "%s" is a smaller service locator that %s', $externalId, $this->formatAlternatives());
+        } else {
+            $msg .= sprintf('the current service locator %s', $this->formatAlternatives());
+        }
+
+        if (!$class) {
+            // no-op
+        } elseif (is_subclass_of($class, ServiceSubscriberInterface::class)) {
+            $msg .= sprintf(' Unless you need extra laziness, try using dependency injection instead. Otherwise, you need to declare it using "%s::getSubscribedServices()".', preg_replace('/([^\\\\]++\\\\)++/', '', $class));
+        } else {
+            $msg .= 'Try using dependency injection instead.';
+        }
+
+        return $msg;
+    }
+
+    private function formatAlternatives(array $alternatives = null, $separator = 'and')
+    {
+        $format = '"%s"%s';
+        if (null === $alternatives) {
+            if (!$alternatives = array_keys($this->factories)) {
+                return 'is empty...';
+            }
+            $format = sprintf('only knows about the %s service%s.', $format, 1 < count($alternatives) ? 's' : '');
+        }
+        $last = array_pop($alternatives);
+
+        return sprintf($format, $alternatives ? implode('", "', $alternatives) : $last, $alternatives ? sprintf(' %s "%s"', $separator, $last) : '');
+    }
 }
--- a/src/Symfony/Component/DependencyInjection/Tests/Compiler/RegisterServiceSubscribersPassTest.php
+++ b/src/Symfony/Component/DependencyInjection/Tests/Compiler/RegisterServiceSubscribersPassTest.php
@ -85,7 +85,7 @@ class RegisterServiceSubscribersPassTest extends TestCase
            'baz' => new ServiceClosureArgument(new TypedReference(CustomDefinition::class, CustomDefinition::class, TestServiceSubscriber::class, ContainerInterface::IGNORE_ON_INVALID_REFERENCE)),
        );

-        $this->assertEquals($expected, $locator->getArgument(0));
+        $this->assertEquals($expected, $container->getDefinition((string) $locator->getFactory()[0])->getArgument(0));
    }

    public function testWithAttributes()
@ -115,7 +115,7 @@ class RegisterServiceSubscribersPassTest extends TestCase
            'baz' => new ServiceClosureArgument(new TypedReference(CustomDefinition::class, CustomDefinition::class, TestServiceSubscriber::class, ContainerInterface::IGNORE_ON_INVALID_REFERENCE)),
        );

-        $this->assertEquals($expected, $locator->getArgument(0));
+        $this->assertEquals($expected, $container->getDefinition((string) $locator->getFactory()[0])->getArgument(0));
    }

    /**
--- a/src/Symfony/Component/DependencyInjection/Tests/Fixtures/php/services_subscriber.php
+++ b/src/Symfony/Component/DependencyInjection/Tests/Fixtures/php/services_subscriber.php
@ -45,6 +45,7 @@ class ProjectServiceContainer extends Container
            'Symfony\\Component\\DependencyInjection\\ContainerInterface' => true,
            'Symfony\\Component\\DependencyInjection\\Tests\\Fixtures\\CustomDefinition' => true,
            'service_locator.jmktfsv' => true,
+            'service_locator.jmktfsv.foo_service' => true,
        );
    }

@ -82,7 +83,7 @@ class ProjectServiceContainer extends Container
     */
    protected function getFooServiceService()
    {
-        return $this->services['foo_service'] = new \Symfony\Component\DependencyInjection\Tests\Fixtures\TestServiceSubscriber(new \Symfony\Component\DependencyInjection\ServiceLocator(array('Symfony\\Component\\DependencyInjection\\Tests\\Fixtures\\CustomDefinition' => function () {
+        return $this->services['foo_service'] = new \Symfony\Component\DependencyInjection\Tests\Fixtures\TestServiceSubscriber(\call_user_func(array(new \Symfony\Component\DependencyInjection\ServiceLocator(array('Symfony\\Component\\DependencyInjection\\Tests\\Fixtures\\CustomDefinition' => function () {
            $f = function (\Symfony\Component\DependencyInjection\Tests\Fixtures\CustomDefinition $v = null) { return $v; }; return $f(${($_ = isset($this->services['Symfony\Component\DependencyInjection\Tests\Fixtures\CustomDefinition']) ? $this->services['Symfony\Component\DependencyInjection\Tests\Fixtures\CustomDefinition'] : $this->services['Symfony\Component\DependencyInjection\Tests\Fixtures\CustomDefinition'] = new \Symfony\Component\DependencyInjection\Tests\Fixtures\CustomDefinition()) && false ?: '_'});
        }, 'Symfony\\Component\\DependencyInjection\\Tests\\Fixtures\\TestServiceSubscriber' => function () {
            $f = function (\Symfony\Component\DependencyInjection\Tests\Fixtures\TestServiceSubscriber $v) { return $v; }; return $f(${($_ = isset($this->services['Symfony\Component\DependencyInjection\Tests\Fixtures\TestServiceSubscriber']) ? $this->services['Symfony\Component\DependencyInjection\Tests\Fixtures\TestServiceSubscriber'] : $this->services['Symfony\Component\DependencyInjection\Tests\Fixtures\TestServiceSubscriber'] = new \Symfony\Component\DependencyInjection\Tests\Fixtures\TestServiceSubscriber()) && false ?: '_'});
@ -90,7 +91,7 @@ class ProjectServiceContainer extends Container
            $f = function (\Symfony\Component\DependencyInjection\Tests\Fixtures\CustomDefinition $v) { return $v; }; return $f(${($_ = isset($this->services['Symfony\Component\DependencyInjection\Tests\Fixtures\TestServiceSubscriber']) ? $this->services['Symfony\Component\DependencyInjection\Tests\Fixtures\TestServiceSubscriber'] : $this->services['Symfony\Component\DependencyInjection\Tests\Fixtures\TestServiceSubscriber'] = new \Symfony\Component\DependencyInjection\Tests\Fixtures\TestServiceSubscriber()) && false ?: '_'});
        }, 'baz' => function () {
            $f = function (\Symfony\Component\DependencyInjection\Tests\Fixtures\CustomDefinition $v = null) { return $v; }; return $f(${($_ = isset($this->services['Symfony\Component\DependencyInjection\Tests\Fixtures\CustomDefinition']) ? $this->services['Symfony\Component\DependencyInjection\Tests\Fixtures\CustomDefinition'] : $this->services['Symfony\Component\DependencyInjection\Tests\Fixtures\CustomDefinition'] = new \Symfony\Component\DependencyInjection\Tests\Fixtures\CustomDefinition()) && false ?: '_'});
-        })));
+        })), 'withContext'), 'foo_service', $this));
    }

    /**
--- a/src/Symfony/Component/DependencyInjection/Tests/ServiceLocatorTest.php
+++ b/src/Symfony/Component/DependencyInjection/Tests/ServiceLocatorTest.php
@ -12,8 +12,9 @@
 namespace Symfony\Component\DependencyInjection\Tests;

 use PHPUnit\Framework\TestCase;
-use Symfony\Component\DependencyInjection\Exception\ServiceNotFoundException;
+use Symfony\Component\DependencyInjection\Container;
 use Symfony\Component\DependencyInjection\ServiceLocator;
+use Symfony\Component\DependencyInjection\ServiceSubscriberInterface;

 class ServiceLocatorTest extends TestCase
 {
@ -59,7 +60,7 @@ class ServiceLocatorTest extends TestCase

    /**
     * @expectedException        \Psr\Container\NotFoundExceptionInterface
-     * @expectedExceptionMessage You have requested a non-existent service "dummy". Did you mean one of these: "foo", "bar"?
+     * @expectedExceptionMessage Service "dummy" not found: the container inside "Symfony\Component\DependencyInjection\Tests\ServiceLocatorTest" is a smaller service locator that only knows about the "foo" and "bar" services.
     */
    public function testGetThrowsOnUndefinedService()
    {
@ -68,13 +69,50 @@ class ServiceLocatorTest extends TestCase
            'bar' => function () { return 'baz'; },
        ));

-        try {
-            $locator->get('dummy');
-        } catch (ServiceNotFoundException $e) {
-            $this->assertSame(array('foo', 'bar'), $e->getAlternatives());
+        $locator->get('dummy');
+    }

-            throw $e;
-        }
+    /**
+     * @expectedException        \Psr\Container\NotFoundExceptionInterface
+     * @expectedExceptionMessage The service "foo" has a dependency on a non-existent service "bar". This locator only knows about the "foo" service.
+     */
+    public function testThrowsOnUndefinedInternalService()
+    {
+        $locator = new ServiceLocator(array(
+            'foo' => function () use (&$locator) { return $locator->get('bar'); },
+        ));
+
+        $locator->get('foo');
+    }
+
+    /**
+     * @expectedException        \Symfony\Component\DependencyInjection\Exception\ServiceCircularReferenceException
+     * @expectedExceptionMessage Circular reference detected for service "bar", path: "bar -> baz -> bar".
+     */
+    public function testThrowsOnCircularReference()
+    {
+        $locator = new ServiceLocator(array(
+            'foo' => function () use (&$locator) { return $locator->get('bar'); },
+            'bar' => function () use (&$locator) { return $locator->get('baz'); },
+            'baz' => function () use (&$locator) { return $locator->get('bar'); },
+        ));
+
+        $locator->get('foo');
+    }
+
+    /**
+     * @expectedException        \Psr\Container\NotFoundExceptionInterface
+     * @expectedExceptionMessage Service "foo" not found: even though it exists in the app's container, the container inside "caller" is a smaller service locator that only knows about the "bar" service. Unless you need extra laziness, try using dependency injection instead. Otherwise, you need to declare it using "SomeServiceSubscriber::getSubscribedServices()".
+     */
+    public function testThrowsInServiceSubscriber()
+    {
+        $container = new Container();
+        $container->set('foo', new \stdClass());
+        $subscriber = new SomeServiceSubscriber();
+        $subscriber->container = new ServiceLocator(array('bar' => function () {}));
+        $subscriber->container = $subscriber->container->withContext('caller', $container);
+
+        $subscriber->getFoo();
    }

    public function testInvoke()
@ -89,3 +127,18 @@ class ServiceLocatorTest extends TestCase
        $this->assertNull($locator('dummy'), '->__invoke() should return null on invalid service');
    }
 }
+
+class SomeServiceSubscriber implements ServiceSubscriberinterface
+{
+    public $container;
+
+    public function getFoo()
+    {
+        return $this->container->get('foo');
+    }
+
+    public static function getSubscribedServices()
+    {
+        return array('bar' => 'stdClass');
+    }
+}