gnu-social/lib/activity.php
2013-06-04 15:21:59 -04:00

764 lines
26 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
public $extra = array(); // extra elements as array(tag, attrs, content)
public $source; // ActivitySource object representing 'home feed'
public $selfLink; // <link rel='self' type='application/atom+xml'>
public $editLink; // <link rel='edit' type='application/atom+xml'>
/**
* 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, $feed);
} else if ($entry->namespaceURI == Activity::SPEC &&
$entry->localName == 'object') {
$this->_fromAtomEntry($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
}
// get immediate object children
$objectEls = ActivityUtils::children($entry, self::OBJECT, self::SPEC);
if (count($objectEls) > 0) {
foreach ($objectEls as $objectEl) {
// Special case for embedded activities
$objectType = ActivityUtils::childContent($objectEl, self::OBJECTTYPE, self::SPEC);
if (!empty($objectType) && $objectType == ActivityObject::ACTIVITY) {
$this->objects[] = new Activity($objectEl);
} else {
$this->objects[] = new ActivityObject($objectEl);
}
}
} else {
// XXX: really?
$this->objects[] = new ActivityObject($entry);
}
$actorEl = $this->_child($entry, self::ACTOR);
if (!empty($actorEl)) {
// Standalone <activity:actor> elements are a holdover from older
// versions of ActivityStreams. Newer feeds should have this data
// integrated straight into <atom:author>.
$this->actor = new ActivityObject($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 = $authorObj->id;
}
}
} else if ($authorEl = $this->_child($entry, self::AUTHOR, self::ATOM)) {
// An <atom:author> in the entry overrides any author info on
// the surrounding feed.
$this->actor = new ActivityObject($authorEl);
} else if (!empty($feed) &&
$subjectEl = $this->_child($feed, self::SUBJECT)) {
// Feed subject is used for things like groups.
// Should actually possibly not be interpreted as an actor...?
$this->actor = new ActivityObject($subjectEl);
} else if (!empty($feed) && $authorEl = $this->_child($feed, self::AUTHOR,
self::ATOM)) {
// If there's no <atom:author> on the entry, it's safe to assume
// the containing feed's authorship info applies.
$this->actor = new ActivityObject($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');
}
// From APP. Might be useful.
$this->selfLink = ActivityUtils::getLink($entry, 'self', 'application/atom+xml');
$this->editLink = ActivityUtils::getLink($entry, 'edit', 'application/atom+xml');
}
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;
}
/**
* Returns an array based on this activity suitable
* for encoding as a JSON object
*
* @return array $activity
*/
function asArray()
{
$activity = array();
// actor
$activity['actor'] = $this->actor->asArray();
// content
$activity['content'] = $this->content;
// generator <-- We could use this when we know a notice is created
// locally. Or if we know the upstream Generator.
// icon <-- possibly a mini object representing verb?
// id
$activity['id'] = $this->id;
// object
if (count($this->objects) == 0) {
common_log(LOG_ERR, "Can't save " . $this->id);
} else {
if (count($this->objects) > 1) {
common_log(LOG_WARNING, "Ignoring " . (count($this->objects) - 1) . " extra objects in JSON output for activity " . $this->id);
}
$object = $this->objects[0];
if ($object instanceof Activity) {
// Sharing a post activity is more like sharing the original object
if ($this->verb == 'share' && $object->verb == 'post') {
// XXX: Here's one for the obfuscation record books
$object = $object->object;
}
}
$activity['object'] = $object->asArray();
if ($object instanceof Activity) {
$activity['object']['objectType'] = 'activity';
}
// Context stuff. For now I'm just sticking most of it
// in a property called "context"
if (!empty($this->context)) {
if (!empty($this->context->location)) {
$loc = $this->context->location;
$activity['location'] = array(
'objectType' => 'place',
'position' => sprintf("%+02.5F%+03.5F/", $loc->lat, $loc->lon),
'lat' => $loc->lat,
'lon' => $loc->lon
);
$name = $loc->getName();
if ($name) {
$activity['location']['displayName'] = $name;
}
$url = $loc->getURL();
if ($url) {
$activity['location']['url'] = $url;
}
}
$activity['to'] = $this->context->getToArray();
$activity['context'] = $this->context->asArray();
}
// Instead of adding enclosures as an extension to JSON
// Activities, it seems like we should be using the
// attachements property of ActivityObject
$attachments = array();
// XXX: OK, this is kinda cheating. We should probably figure out
// what kind of objects these are based on mime-type and then
// create specific object types. Right now this rely on
// duck-typing. Also, we should include an embed code for
// video attachments.
foreach ($this->enclosures as $enclosure) {
if (is_string($enclosure)) {
$attachments[]['id'] = $enclosure;
} else {
$attachments[]['id'] = $enclosure->url;
$mediaLink = new ActivityStreamsMediaLink(
$enclosure->url,
null,
null,
$enclosure->mimetype
// XXX: Add 'size' as an extension to MediaLink?
);
$attachments[]['mediaLink'] = $mediaLink->asArray(); // extension
if ($enclosure->title) {
$attachments[]['displayName'] = $enclosure->title;
}
}
}
if (!empty($attachments)) {
$activity['object']['attachments'] = $attachments;
}
}
// published
$activity['published'] = self::iso8601Date($this->time);
// provider
$provider = array(
'objectType' => 'service',
'displayName' => common_config('site', 'name'),
'url' => common_root_url()
);
$activity['provider'] = $provider;
// target
if (!empty($this->target)) {
$activity['target'] = $this->target->asArray();
}
// title
$activity['title'] = $this->title;
// updated <-- Optional. Should we use this to indicate the time we r
// eceived a remote notice? Probably not.
// verb
//
// We can probably use the whole schema URL here but probably the
// relative simple name is easier to parse
$activity['verb'] = substr($this->verb, strrpos($this->verb, '/') + 1);
// url
$activity['url'] = $this->id;
/* Purely extensions hereafter */
if ($activity['verb'] == 'post') {
$tags = array();
foreach ($this->categories as $cat) {
if (mb_strlen($cat->term) > 0) {
// Couldn't figure out which object type to use, so...
$tags[] = array('objectType' => 'http://activityschema.org/object/hashtag',
'displayName' => $cat->term);
}
}
if (count($tags) > 0) {
$activity['object']['tags'] = $tags;
}
}
// XXX: a bit of a hack... Since JSON isn't namespaced we probably
// shouldn't be using 'statusnet:notice_info', but this will work
// for the moment.
foreach ($this->extra as $e) {
list($objectName, $props, $txt) = $e;
if (!empty($objectName)) {
$activity[$objectName] = $props;
}
}
return array_filter($activity);
}
function asString($namespace=false, $author=true, $source=false)
{
$xs = new XMLStringer(true);
$this->outputTo($xs, $namespace, $author, $source);
return $xs->getString();
}
function outputTo($xs, $namespace=false, $author=true, $source=false, $tag='entry')
{
if ($namespace) {
$attrs = array('xmlns' => 'http://www.w3.org/2005/Atom',
'xmlns:thr' => 'http://purl.org/syndication/thread/1.0',
'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',
'xmlns:statusnet' => 'http://status.net/schema/api/1/');
} else {
$attrs = array();
}
$xs->elementStart($tag, $attrs);
if ($tag != 'entry') {
$xs->element('activity:object-type', null, ActivityObject::ACTIVITY);
}
if ($this->verb == ActivityVerb::POST && count($this->objects) == 1 && $tag == 'entry') {
$obj = $this->objects[0];
$obj->outputTo($xs, null);
} else {
$xs->element('id', null, $this->id);
$xs->element('title', null, $this->title);
$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);
}
}
$xs->element('activity:verb', null, $this->verb);
$published = self::iso8601Date($this->time);
$xs->element('published', null, $published);
$xs->element('updated', null, $published);
if ($author) {
$this->actor->outputTo($xs, 'author');
}
if ($this->verb != ActivityVerb::POST || count($this->objects) != 1 || $tag != 'entry') {
foreach($this->objects as $object) {
if ($object instanceof Activity) {
$object->outputTo($xs, false, true, true, 'activity:object');
} else {
$object->outputTo($xs, 'activity:object');
}
}
}
if (!empty($this->context)) {
if (!empty($this->context->replyToID)) {
if (!empty($this->context->replyToUrl)) {
$xs->element('thr:in-reply-to',
array('ref' => $this->context->replyToID,
'href' => $this->context->replyToUrl));
} else {
$xs->element('thr:in-reply-to',
array('ref' => $this->context->replyToID));
}
}
if (!empty($this->context->replyToUrl)) {
$xs->element('link', array('rel' => 'related',
'href' => $this->context->replyToUrl));
}
if (!empty($this->context->conversation)) {
$xs->element('link', array('rel' => 'ostatus:conversation',
'href' => $this->context->conversation));
}
foreach ($this->context->attention as $attnURI) {
$xs->element('link', array('rel' => 'ostatus:attention',
'href' => $attnURI));
$xs->element('link', array('rel' => 'mentioned',
'href' => $attnURI));
}
// XXX: shoulda used ActivityVerb::SHARE
if (!empty($this->context->forwardID)) {
if (!empty($this->context->forwardUrl)) {
$xs->element('ostatus:forward',
array('ref' => $this->context->forwardID,
'href' => $this->context->forwardUrl));
} else {
$xs->element('ostatus:forward',
array('ref' => $this->context->forwardID));
}
}
if (!empty($this->context->location)) {
$loc = $this->context->location;
$xs->element('georss:point', null, $loc->lat . ' ' . $loc->lon);
}
}
if ($this->target) {
$this->target->outputTo($xs, 'activity:target');
}
foreach ($this->categories as $cat) {
$cat->outputTo($xs);
}
// can be either URLs or enclosure objects
foreach ($this->enclosures as $enclosure) {
if (is_string($enclosure)) {
$xs->element('link', array('rel' => 'enclosure',
'href' => $enclosure));
} else {
$attributes = array('rel' => 'enclosure',
'href' => $enclosure->url,
'type' => $enclosure->mimetype,
'length' => $enclosure->size);
if ($enclosure->title) {
$attributes['title'] = $enclosure->title;
}
$xs->element('link', $attributes);
}
}
// Info on the source feed
if ($source && !empty($this->source)) {
$xs->elementStart('source');
$xs->element('id', null, $this->source->id);
$xs->element('title', null, $this->source->title);
if (array_key_exists('alternate', $this->source->links)) {
$xs->element('link', array('rel' => 'alternate',
'type' => 'text/html',
'href' => $this->source->links['alternate']));
}
if (array_key_exists('self', $this->source->links)) {
$xs->element('link', array('rel' => 'self',
'type' => 'application/atom+xml',
'href' => $this->source->links['self']));
}
if (array_key_exists('license', $this->source->links)) {
$xs->element('link', array('rel' => 'license',
'href' => $this->source->links['license']));
}
if (!empty($this->source->icon)) {
$xs->element('icon', null, $this->source->icon);
}
if (!empty($this->source->updated)) {
$xs->element('updated', null, $this->source->updated);
}
$xs->elementEnd('source');
}
if (!empty($this->selfLink)) {
$xs->element('link', array('rel' => 'self',
'type' => 'application/atom+xml',
'href' => $this->selfLink));
}
if (!empty($this->editLink)) {
$xs->element('link', array('rel' => 'edit',
'type' => 'application/atom+xml',
'href' => $this->editLink));
}
// For throwing in extra elements; used for statusnet:notice_info
foreach ($this->extra as $el) {
list($tag, $attrs, $content) = $el;
$xs->element($tag, $attrs, $content);
}
$xs->elementEnd($tag);
return;
}
private function _child($element, $tag, $namespace=self::SPEC)
{
return ActivityUtils::child($element, $tag, $namespace);
}
/**
* For consistency, we'll always output UTC rather than local time.
* Note that clients *should* accept any timezone we give them as long
* as it's properly formatted.
*
* @param int $tm Unix timestamp
* @return string
*/
static function iso8601Date($tm)
{
$dateStr = date('d F Y H:i:s', $tm);
$d = new DateTime($dateStr, new DateTimeZone('UTC'));
return $d->format('c');
}
}