gnu-social/lib/activity.php

398 lines
13 KiB
PHP

<?php
/**
* StatusNet, the distributed open-source microblogging tool
*
* An activity
*
* PHP version 5
*
* LICENCE: This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* @category Feed
* @package StatusNet
* @author Evan Prodromou <evan@status.net>
* @author Zach Copley <zach@status.net>
* @copyright 2010 StatusNet, Inc.
* @license http://www.fsf.org/licensing/licenses/agpl-3.0.html AGPLv3
* @link http://status.net/
*/
if (!defined('STATUSNET')) {
exit(1);
}
/**
* An activity in the ActivityStrea.ms world
*
* An activity is kind of like a sentence: someone did something
* to something else.
*
* 'someone' is the 'actor'; 'did something' is the verb;
* 'something else' is the object.
*
* @category OStatus
* @package StatusNet
* @author Evan Prodromou <evan@status.net>
* @copyright 2010 StatusNet, Inc.
* @license http://www.fsf.org/licensing/licenses/agpl-3.0.html AGPLv3
* @link http://status.net/
*/
class Activity
{
const SPEC = 'http://activitystrea.ms/spec/1.0/';
const SCHEMA = 'http://activitystrea.ms/schema/1.0/';
const MEDIA = 'http://purl.org/syndication/atommedia';
const VERB = 'verb';
const OBJECT = 'object';
const ACTOR = 'actor';
const SUBJECT = 'subject';
const OBJECTTYPE = 'object-type';
const CONTEXT = 'context';
const TARGET = 'target';
const ATOM = 'http://www.w3.org/2005/Atom';
const AUTHOR = 'author';
const PUBLISHED = 'published';
const UPDATED = 'updated';
const RSS = null; // no namespace!
const PUBDATE = 'pubDate';
const DESCRIPTION = 'description';
const GUID = 'guid';
const SELF = 'self';
const IMAGE = 'image';
const URL = 'url';
const DC = 'http://purl.org/dc/elements/1.1/';
const CREATOR = 'creator';
const CONTENTNS = 'http://purl.org/rss/1.0/modules/content/';
const ENCODED = 'encoded';
public $actor; // an ActivityObject
public $verb; // a string (the URL)
public $objects = array(); // an array of ActivityObjects
public $target; // an ActivityObject
public $context; // an ActivityObject
public $time; // Time of the activity
public $link; // an ActivityObject
public $entry; // the source entry
public $feed; // the source feed
public $summary; // summary of activity
public $content; // HTML content of activity
public $id; // ID of the activity
public $title; // title of the activity
public $categories = array(); // list of AtomCategory objects
public $enclosures = array(); // list of enclosure URL references
/**
* Turns a regular old Atom <entry> into a magical activity
*
* @param DOMElement $entry Atom entry to poke at
* @param DOMElement $feed Atom feed, for context
*/
function __construct($entry = null, $feed = null)
{
if (is_null($entry)) {
return;
}
// Insist on a feed's root DOMElement; don't allow a DOMDocument
if ($feed instanceof DOMDocument) {
throw new ClientException(
// TRANS: Client exception thrown when a feed instance is a DOMDocument.
_('Expecting a root feed element but got a whole XML document.')
);
}
$this->entry = $entry;
$this->feed = $feed;
if ($entry->namespaceURI == Activity::ATOM &&
$entry->localName == 'entry') {
$this->_fromAtomEntry($entry, $feed);
} else if ($entry->namespaceURI == Activity::RSS &&
$entry->localName == 'item') {
$this->_fromRssItem($entry, $feed);
} else {
// Low level exception. No need for i18n.
throw new Exception("Unknown DOM element: {$entry->namespaceURI} {$entry->localName}");
}
}
function _fromAtomEntry($entry, $feed)
{
$pubEl = $this->_child($entry, self::PUBLISHED, self::ATOM);
if (!empty($pubEl)) {
$this->time = strtotime($pubEl->textContent);
} else {
// XXX technically an error; being liberal. Good idea...?
$updateEl = $this->_child($entry, self::UPDATED, self::ATOM);
if (!empty($updateEl)) {
$this->time = strtotime($updateEl->textContent);
} else {
$this->time = null;
}
}
$this->link = ActivityUtils::getPermalink($entry);
$verbEl = $this->_child($entry, self::VERB);
if (!empty($verbEl)) {
$this->verb = trim($verbEl->textContent);
} else {
$this->verb = ActivityVerb::POST;
// XXX: do other implied stuff here
}
$objectEls = $entry->getElementsByTagNameNS(self::SPEC, self::OBJECT);
if ($objectEls->length > 0) {
for ($i = 0; $i < $objectEls->length; $i++) {
$objectEl = $objectEls->item($i);
$this->objects[] = new ActivityObject($objectEl);
}
} else {
$this->objects[] = new ActivityObject($entry);
}
$actorEl = $this->_child($entry, self::ACTOR);
if (!empty($actorEl)) {
$this->actor = new ActivityObject($actorEl);
// Cliqset has bad actor IDs (just nickname of user). We
// work around it by getting the author data and using its
// id instead
if (!preg_match('/^\w+:/', $this->actor->id)) {
$authorEl = ActivityUtils::child($entry, 'author');
if (!empty($authorEl)) {
$authorObj = new ActivityObject($authorEl);
$this->actor->id = $authorObj->id;
}
}
} else if (!empty($feed) &&
$subjectEl = $this->_child($feed, self::SUBJECT)) {
$this->actor = new ActivityObject($subjectEl);
} else if ($authorEl = $this->_child($entry, self::AUTHOR, self::ATOM)) {
$this->actor = new ActivityObject($authorEl);
} else if (!empty($feed) && $authorEl = $this->_child($feed, self::AUTHOR,
self::ATOM)) {
$this->actor = new ActivityObject($authorEl);
}
$contextEl = $this->_child($entry, self::CONTEXT);
if (!empty($contextEl)) {
$this->context = new ActivityContext($contextEl);
} else {
$this->context = new ActivityContext($entry);
}
$targetEl = $this->_child($entry, self::TARGET);
if (!empty($targetEl)) {
$this->target = new ActivityObject($targetEl);
}
$this->summary = ActivityUtils::childContent($entry, 'summary');
$this->id = ActivityUtils::childContent($entry, 'id');
$this->content = ActivityUtils::getContent($entry);
$catEls = $entry->getElementsByTagNameNS(self::ATOM, 'category');
if ($catEls) {
for ($i = 0; $i < $catEls->length; $i++) {
$catEl = $catEls->item($i);
$this->categories[] = new AtomCategory($catEl);
}
}
foreach (ActivityUtils::getLinks($entry, 'enclosure') as $link) {
$this->enclosures[] = $link->getAttribute('href');
}
}
function _fromRssItem($item, $channel)
{
$verbEl = $this->_child($item, self::VERB);
if (!empty($verbEl)) {
$this->verb = trim($verbEl->textContent);
} else {
$this->verb = ActivityVerb::POST;
// XXX: do other implied stuff here
}
$pubDateEl = $this->_child($item, self::PUBDATE, self::RSS);
if (!empty($pubDateEl)) {
$this->time = strtotime($pubDateEl->textContent);
}
if ($authorEl = $this->_child($item, self::AUTHOR, self::RSS)) {
$this->actor = ActivityObject::fromRssAuthor($authorEl);
} else if ($dcCreatorEl = $this->_child($item, self::CREATOR, self::DC)) {
$this->actor = ActivityObject::fromDcCreator($dcCreatorEl);
} else if ($posterousEl = $this->_child($item, ActivityObject::AUTHOR, ActivityObject::POSTEROUS)) {
// Special case for Posterous.com
$this->actor = ActivityObject::fromPosterousAuthor($posterousEl);
} else if (!empty($channel)) {
$this->actor = ActivityObject::fromRssChannel($channel);
} else {
// No actor!
}
$this->title = ActivityUtils::childContent($item, ActivityObject::TITLE, self::RSS);
$contentEl = ActivityUtils::child($item, self::ENCODED, self::CONTENTNS);
if (!empty($contentEl)) {
// <content:encoded> XML node's text content is HTML; no further processing needed.
$this->content = $contentEl->textContent;
} else {
$descriptionEl = ActivityUtils::child($item, self::DESCRIPTION, self::RSS);
if (!empty($descriptionEl)) {
// Per spec, <description> must be plaintext.
// In practice, often there's HTML... but these days good
// feeds are using <content:encoded> which is explicitly
// real HTML.
// We'll treat this following spec, and do HTML escaping
// to convert from plaintext to HTML.
$this->content = htmlspecialchars($descriptionEl->textContent);
}
}
$this->link = ActivityUtils::childContent($item, ActivityUtils::LINK, self::RSS);
// @fixme enclosures
// @fixme thumbnails... maybe
$guidEl = ActivityUtils::child($item, self::GUID, self::RSS);
if (!empty($guidEl)) {
$this->id = $guidEl->textContent;
if ($guidEl->hasAttribute('isPermaLink') && $guidEl->getAttribute('isPermaLink') != 'false') {
// overwrites <link>
$this->link = $this->id;
}
}
$this->objects[] = new ActivityObject($item);
$this->context = new ActivityContext($item);
}
/**
* Returns an Atom <entry> based on this activity
*
* @return DOMElement Atom entry
*/
function toAtomEntry()
{
return null;
}
function asString($namespace=false, $author=true)
{
$xs = new XMLStringer(true);
if ($namespace) {
$attrs = array('xmlns' => 'http://www.w3.org/2005/Atom',
'xmlns:activity' => 'http://activitystrea.ms/spec/1.0/',
'xmlns:georss' => 'http://www.georss.org/georss',
'xmlns:ostatus' => 'http://ostatus.org/schema/1.0',
'xmlns:poco' => 'http://portablecontacts.net/spec/1.0',
'xmlns:media' => 'http://purl.org/syndication/atommedia');
} else {
$attrs = array();
}
$xs->elementStart('entry', $attrs);
$xs->element('id', null, $this->id);
$xs->element('title', null, $this->title);
$xs->element('published', null, self::iso8601Date($this->time));
$xs->element('content', array('type' => 'html'), $this->content);
if (!empty($this->summary)) {
$xs->element('summary', null, $this->summary);
}
if (!empty($this->link)) {
$xs->element('link', array('rel' => 'alternate',
'type' => 'text/html'),
$this->link);
}
// XXX: add context
if ($author) {
$xs->elementStart('author');
$xs->element('uri', array(), $this->actor->id);
if ($this->actor->title) {
$xs->element('name', array(), $this->actor->title);
}
$xs->elementEnd('author');
$xs->raw($this->actor->asString('activity:actor'));
}
$xs->element('activity:verb', null, $this->verb);
if (!empty($this->objects)) {
foreach($this->objects as $object) {
$xs->raw($object->asString());
}
}
if ($this->target) {
$xs->raw($this->target->asString('activity:target'));
}
foreach ($this->categories as $cat) {
$xs->raw($cat->asString());
}
$xs->elementEnd('entry');
return $xs->getString();
}
private function _child($element, $tag, $namespace=self::SPEC)
{
return ActivityUtils::child($element, $tag, $namespace);
}
static function iso8601Date($tm)
{
$dateStr = date('d F Y H:i:s', $tm);
$d = new DateTime($dateStr, new DateTimeZone('UTC'));
$d->setTimezone(new DateTimeZone(common_timezone()));
return $d->format('c');
}
}