aboutsummaryrefslogtreecommitdiff
path: root/engine/lib/river.php
blob: 676b0fce0bd87e4d95588a719ff02025418139df (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
<?php
	/**
	 * Elgg river.
	 * Functions for listening for and generating the river out of the system log.
	 * 
	 * @package Elgg
	 * @subpackage Core
	 * @license http://www.gnu.org/licenses/old-licenses/gpl-2.0.html GNU Public License version 2
	 * @author Curverider Ltd
	 * @copyright Curverider Ltd 2008
	 * @link http://elgg.org/
	 */

	/**
	 * @class ElggRiverComponent Component passed to river views.
	 * This class represents all the necessary information for constructing a river article - this includes:
	 *  - The user who performed the action
	 *  - The object the action was performed on
	 *  - The event performed
	 *  - Any related objects
	 * 
	 * @author Curverider Ltd
	 */
	class ElggRiverStatement
	{
		/**
		 * Object in question (may be a relationship event or a metadata event). In the case of a relationship this is an array containing 
		 * the objects that the relationship is established between. in the case of metadata it consists of 
		 */
		private $object;
		
		/**
		 * The log event (create / update etc).
		 */
		private $log_event; 
		
		/**
		 * The subject who created this event (the user).
		 */
		private $subject;
		
		/**
		 * When the event occured.
		 */
		private $timestamp;
		
		/**
		 * Create the statement.
		 *
		 * @param ElggUser $subject The subject (the user who created this)
		 * @param string $event The event.
		 * @param mixed $object The object, either an ElggEntity or an associated array 
		 * 	('subject' => ElggEntity, 'relationship' => relationship, 'object' => ElggEntity) or 
		 *  ('subject' => ElggEntity, 'object' => ElggEntity)
		 * @param int $timestamp The timestamp
		 */
		public function __construct(ElggUser $subject, $event, $object, $timestamp)
		{
			$this->setSubject($subject);
			$this->setEvent($event);
			$this->setObject($object);
			$this->setTimestamp($timestamp);
		}
		
		/**
		 * Set the subject.
		 *
		 * @param ElggEntity $subject The subject.
		 */
		public function setSubject(ElggEntity $subject) { $this->subject = $subject; }
		
		/**
		 * Return the user that created this event - the subject of the statement.
		 * @return ElggUser
		 */
		public function getSubject() { return $this->subject; }
		
		/**
		 * Return the user who initiated this event (an alias of getSubject();
		 * @return ElggUser
		 */
		public function getByUser() { return $this->getSubject(); }
		
		/**
		 * Set the object.
		 *
		 * @param mixed $object ElggEntity or array.
		 * @return bool
		 */
		public function setObject($object)
		{
			if (is_array($object))
			{
				/*if (
					(!isset($object['subject'])) ||
					(
						(!($object['subject'] instanceof ElggEntity)) ||
						(!($object['subject'] instanceof ElggExtender))
					)
				)
					return false;
				
				if ( (!isset($object['object'])) || (!($object['object'] instanceof ElggEntity)) )
					return false;
					*/
				$this->object = $object;
				
				return true;
			}
			else if ($object instanceof ElggEntity)
			{
				$this->object = $object;
				
				return true;
			}
			
			return false;
		}
		
		/**
		 * Return the accusitive object of the statement. This is either an object in isolation, or an array containing
		 * the parts of the statement.
		 * 
		 * E.g. 
		 * 
		 * 	For the statement "User X created object Y", this function will return object Y.
		 *  
		 * 	However, for a statement "User X is now friends with User Y" you are essentially making the system level statement
		 *  "User X has created a relationship of type friend between Y and Z" (where X is almost always going to be the same as Y).. therefore
		 *  this function will return a three element array associative containing the relationship type, plus the elements the relationship 
		 *  is between ['subject', 'relationship', 'object'].
		 * 
		 *  Also, if you are updating a bit of metadata about an object this a two element array: ['subject', 'object'].
		 *  Which is making the statement "User X updated some Metadata (subject) about object (object) Y
		 * 
		 * @return mixed
		 */
		public function getObject() { return $this->object; }
		
		/**
		 * Set the log event.
		 *
		 * @param string $event The event - e.g. "update".
		 */
		public function setEvent($event) { $this->log_event = $event; }
		
		/**
		 * Return the event in the system log that this action relates to (eg, "create", "update").
		 * @return string
		 */
		public function getEvent() { return $this->log_event; }
		
		/**
		 * Set when this event occured.
		 *
		 * @param int $timestamp Unix TS
		 */
		public function setTimestamp($timestamp) { $this->timestamp = $timestamp; }
		
		/**
		 * Retrieve when this event occured.
		 *
		 * @return int Unix TS
		 */
		public function getTimestamp() { return $this->timestamp; }
	}

	/**
	 * Perform a somewhat complicated query to extract river data from the system log based on available views.
	 * 
	 * NOTE: Do not use this function directly. It is called elsewhere and is subject to change without warning.
	 *
	 * @param unknown_type $by_user
	 * @param unknown_type $relationship
	 * @param unknown_type $limit
	 * @param unknown_type $offset
	 * @return unknown
	 */
	function __get_river_from_log($by_user = "", $relationship = "", $limit = 10, $offset = 0)
	{
		global $CONFIG;
	
		// Get all potential river events from available view
		$river_events = array(); 
		$river_views = elgg_view_tree('river');
		foreach ($river_views as $view)
		{
			$fragments = explode('/', $view);

			if ((isset($fragments[0])) && ($fragments[0] == 'river'))
			{
				if (isset($fragments[1]))
				{
					$f = array();
					for ($n = 1; $n < count($fragments); $n++)
					{
						$val = sanitise_string($fragments[$n]);
						switch($n)
						{
							case 1: $key = 'type'; break;
							case 2: $key = 'subtype'; break;
							case 3: $key = 'event'; break;
						}
						$f[$key] = $val;
					}
					$river_events[] = $f; 
					
				}
			}
		}
		// Construct query
		
		// Objects
		$n = 0;
		foreach ($river_events as $details)
		{
			// Get what we're talking about
		
			if ((isset($details['subtype'])) && ($details['subtype'] == 'default')) $details['subtype'] = '';
			
			if ((isset($details['type'])) && (isset($details['event']))) {
				if ($n>0) $obj_query .= " or ";
				
				$access = "";
				if ($details['type']!='relationship')
					$access = " and " . get_access_sql_suffix('sl');
				 
				$obj_query .= "( sl.object_type='{$details['type']}' and sl.object_subtype='{$details['subtype']}' and sl.event='{$details['event']}' $access )";
				
				$n++;
			}
		
		}		
	
		// User
		$user = "sl.performed_by_guid in (".implode(',', $by_user).")";
		
		// Relationship
		$relationship_query = "";
		$relationship_join = "";
		if ($relationship)
		{
			$relationship_join = " join {$CONFIG->dbprefix}entity_relationships r on sl.performed_by_guid=r.entity_guid ";
			$relationship_query = "r.relationship = '$relationship'";
		}
		
		$query = "SELECT sl.* from {$CONFIG->dbprefix}system_log sl $relationship_join where $user and $relationship_query ($obj_query) order by sl.time_created desc  limit $offset, $limit";

		// fetch data from system log (needs optimisation)
		return get_data($query);
	}
	
	/**
	 * Construct a river statement out of an entry in the system log.
	 *
	 * @param stdClass $log_entry
	 * @return mixed Either an ElggRiverStatement or false
	 */
	function construct_riverstatement_from_log($log_entry)
	{
		if (!($log_entry instanceof stdClass)) return false;
		
		$log = $log_entry;
		
		// See if we have access to the object we're talking about
		$event = $log->event;
		$class = $log->object_class;
		$type = $log->object_type;
		$subtype = $log->object_subtype;
		$tmp = new $class();
		$object = $tmp->getObjectFromID($log->object_id);	
		$by_user_obj = get_entity($log->performed_by_guid);
				
		if ( ($object) && ($object instanceof $class))
		{
			// Construct the statement
			$statement_object = $object; // Simple object, we don't need to do more
					
			// This is a relationship, slighty more complicated
			if ($object instanceof ElggRelationship) {
						
				$statement_object = array(
					'subject' => get_entity($object->guid_one),
					'relationship' => $object->relationship,// Didn' cast to int here deliberately
					'object' => get_entity($object->guid_two) 
				);
				
			// Metadata or annotations, also slightly more complicated
			} else if ($object instanceof ElggExtender) {
				$statement_object = array(
					'subject' => $object,
					'object' => get_entity($object->entity_guid)  
				);
			}

			// Put together a river statement
			return new ElggRiverStatement($by_user_obj, $event, $statement_object, $log->time_created);
		}
		
		return false;
	}
	
	/**
	 * Extract a list of river events from the current system log.
	 * This function retrieves the objects from the system log and will attempt to render 
	 * the view "river/CLASSNAME/EVENT" where CLASSNAME is the class of the object the system event is referring to,
	 * and EVENT is the event (create, update, delete etc).
	 * 
	 * This view will be passed the log entry (as 'log_entry') and the object (as 'object') which will be accessable 
	 * through the $vars[] array.
	 * 
	 * It returns an array of the result of each of these views.
	 * 
	 * \TODO: Limit to just one user or just one user's friends
	 * \TODO: Make this more efficient / reduce DB queries.
	 * 
	 * @param int $by_user The user who initiated the event.
	 * @param string $relationship Limit return results to only those users who $by_user has $relationship with.
	 * @param int $limit Maximum number of events to show
	 * @param int $offset An offset
	 * @return array of river entities rendered with the appropriate view.
	 */
	function get_river_entries($by_user = "", $relationship = "", $limit = 10, $offset = 0)
	{
		global $CONFIG;
		
		$limit = (int)$limit;
		$offset = (int)$offset;
		$relationship = sanitise_string($relationship);
		
		if (is_array($by_user) && sizeof($by_user) > 0) {
			foreach($by_user as $key => $val) {
				$by_user[$key] = (int) $val;
			}
		} else {
			$by_user = array((int)$by_user);
		}
		
		// Get river data
		$log_data = __get_river_from_log($by_user, $relationship, $limit, $offset);
		
		// until count reached, loop through and render
		$river = array();
		
		if ($log_data)
		{
			foreach ($log_data as $log)
			{
				$statement = construct_riverstatement_from_log($log);
				
				$event = $log->event;
				$class = $log->object_class;
				$type = $log->object_type;
				$subtype = $log->object_subtype;
				$tmp = new $class();
				$object = $tmp->getObjectFromID($log->object_id);	
				$by_user_obj = get_entity($log->performed_by_guid);
				
				// Belts and braces
				if ($statement)
				{
					$tam = "";
					
					// Now construct and call the appropriate views
					
					if ($subtype == "widget") { // Special case for widgets
						$subtype = "widget/" . $object->handler;
					}
					if ($subtype == '')
						$subtype = 'default';
						
					$tam = elgg_view("river/$type/$subtype/$event", array(
						'statement' => $statement
					));
					
					
					// Giftwrap
					if (!empty($tam)) {
						$tam = elgg_view("river/wrapper",array(
									'entry' => $tam,
									'time' => $log->time_created,
									'event' => $event,
									'statement' => $statement 
						));
					}
					
					$river[] = $tam;
				}
			}
		}
		
		return $river;
		
	}
	
	/**
	 * Extract entities from the system log and produce them as an OpenDD stream.
	 * This stream can be subscribed to and reconstructed on another system as an activity stream.
	 *
	 * @param int $by_user The user who initiated the event.
	 * @param string $relationship Limit return results to only those users who $by_user has $relationship with.
	 * @param int $limit Maximum number of events to show
	 * @param int $offset An offset
	 * @return ODDDocument
	 */
	function get_river_entries_as_opendd($by_user = "", $relationship = "", $limit = 10, $offset = 0)
	{
		global $CONFIG;
		
		$limit = (int)$limit;
		$offset = (int)$offset;
		$relationship = sanitise_string($relationship);
		
		if (is_array($by_user) && sizeof($by_user) > 0) {
			foreach($by_user as $key => $val) {
				$by_user[$key] = (int) $val;
			}
		} else {
			$by_user = array((int)$by_user);
		}
		
		// Get river data
		$log_data = __get_river_from_log($by_user, $relationship, $limit, $offset);
		
		// River objects
		$river = new ODDDocument();	
		if ($log_data)
		{
			foreach ($log_data as $log)
			{		
				$event = $log->event;
				$class = $log->object_class;
				$type = $log->object_type;
				$subtype = $log->object_subtype;
				$tmp = new $class();
				$object = $tmp->getObjectFromID($log->object_id);	
				$by_user_obj = get_entity($log->performed_by_guid);
				
				// Belts and braces
				if ($object instanceof $class)
				{
					$relationship_obj = NULL;
							
					// Handle updates of entities
					if ($object instanceof ElggEntity)
					{
						$relationship_obj = new ODDRelationship(
							guid_to_uuid($log->performed_by_guid),
							$log->event,
							guid_to_uuid($log->object_id)
						);
					}
							
					// Handle updates of metadata
					if ($object instanceof ElggExtender)
					{
						$odd = $object->export();
						$relationship_obj = new ODDRelationship(
							guid_to_uuid($log->performed_by_guid),
							$log->event,
							$odd->getAttribute('uuid')
						);
					}
							
					// Handle updates of relationships
					if ($object instanceof ElggRelationship)
					{
						$odd = $object->export();
						$relationship_obj = new ODDRelationship(
							guid_to_uuid($log->performed_by_guid),
							$log->event,
							$odd->getAttribute('uuid')
						);
					}
							
					// If we have handled it then add it to the document
					if ($relationship_obj) {
						$relationship_obj->setPublished($log->time_created); 
						$river->addElement($relationship_obj);
					}
				}
			}
			
		}		
		return $river;
		
	}
	
	/**
	 * Extract a list of river events from the current system log, from a given user's friends.
	 *
	 * @seeget_river_entries 
	 * @param int $by_user The user whose friends we're checking for.
	 * @param int $limit Maximum number of events to show
	 * @param int $offset An offset
	 * @return array of river entities rendered with the appropriate view.
	 */
	function get_river_entries_friends($by_user, $limit = 10, $offset = 0) {
		$friendsarray = "";
		if ($friends = get_user_friends($by_user, "", 9999)) {
			$friendsarray = array();
			foreach($friends as $friend) {
				$friendsarray[] = $friend->getGUID();
			}
		}
		
		return get_river_entries($friendsarray,"",$limit,$offset);
	}

	/**
	 * Simplify drawing a river for a given user.
	 *
	 * @param int $guid The user
	 * @param unknown_type $limit Limit
	 * @param unknown_type $offset Offset
	 * @param string $view Optional view to use to display the river (dashboard is assumed)
	 */
	function elgg_view_river($guid, $limit = 10, $offset = 0, $view = 'river/dashboard')
	{
		return elgg_view($view, array('river' => get_river_entries($guid,"", $limit, $offset)));
	}
	
	/**
	 * Simplify drawing a river for a given user, showing their friend's activity
	 *
	 * @param int $guid The user
	 * @param unknown_type $limit Limit
	 * @param unknown_type $offset Offset
	 * @param string $view Optional view to use to display the river (dashboard is assumed)
	 */
	function elgg_view_friend_river($guid, $limit = 10, $offset = 0, $view = 'river/dashboard')
	{
		return elgg_view($view, array('river' => get_river_entries_friends($guid, $limit, $offset)));
	}
?>