summaryrefslogtreecommitdiffstats
path: root/web/lib/aurjson.class.php
blob: 0ac586fe4dee23971d3da32018e5ce473185b3e4 (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
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
<?php

include_once("aur.inc.php");

/*
 * This class defines a remote interface for fetching data from the AUR using
 * JSON formatted elements.
 *
 * @package rpc
 * @subpackage classes
 */
class AurJSON {
	private $dbh = false;
	private $version = 1;
	private static $exposed_methods = array(
		'search', 'info', 'multiinfo', 'msearch', 'suggest',
		'suggest-pkgbase', 'get-comment-form'
	);
	private static $exposed_fields = array(
		'name', 'name-desc', 'maintainer',
		'depends', 'makedepends', 'checkdepends', 'optdepends'
	);
	private static $exposed_depfields = array(
		'depends', 'makedepends', 'checkdepends', 'optdepends'
	);
	private static $fields_v1 = array(
		'Packages.ID', 'Packages.Name',
		'PackageBases.ID AS PackageBaseID',
		'PackageBases.Name AS PackageBase', 'Version',
		'Description', 'URL', 'NumVotes', 'OutOfDateTS AS OutOfDate',
		'Users.UserName AS Maintainer',
		'SubmittedTS AS FirstSubmitted', 'ModifiedTS AS LastModified',
		'Licenses.Name AS License'
	);
	private static $fields_v2 = array(
		'Packages.ID', 'Packages.Name',
		'PackageBases.ID AS PackageBaseID',
		'PackageBases.Name AS PackageBase', 'Version',
		'Description', 'URL', 'NumVotes', 'OutOfDateTS AS OutOfDate',
		'Users.UserName AS Maintainer',
		'SubmittedTS AS FirstSubmitted', 'ModifiedTS AS LastModified'
	);
	private static $fields_v4 = array(
		'Packages.ID', 'Packages.Name',
		'PackageBases.ID AS PackageBaseID',
		'PackageBases.Name AS PackageBase', 'Version',
		'Description', 'URL', 'NumVotes', 'Popularity',
		'OutOfDateTS AS OutOfDate', 'Users.UserName AS Maintainer',
		'SubmittedTS AS FirstSubmitted', 'ModifiedTS AS LastModified'
	);
	private static $numeric_fields = array(
		'ID', 'PackageBaseID', 'NumVotes', 'OutOfDate',
		'FirstSubmitted', 'LastModified'
	);
	private static $decimal_fields = array(
		'Popularity'
	);

	/*
	 * Handles post data, and routes the request.
	 *
	 * @param string $post_data The post data to parse and handle.
	 *
	 * @return string The JSON formatted response data.
	 */
	public function handle($http_data) {
		/*
		 * Unset global aur.inc.php Pragma header. We want to allow
		 * caching of data in proxies, but require validation of data
		 * (if-none-match) if possible.
		 */
		header_remove('Pragma');
		/*
		 * Overwrite cache-control header set in aur.inc.php to allow
		 * caching, but require validation.
		 */
		header('Cache-Control: public, must-revalidate, max-age=0');
		header('Content-Type: application/json, charset=utf-8');

		if (isset($http_data['v'])) {
			$this->version = intval($http_data['v']);
		}
		if ($this->version < 1 || $this->version > 5) {
			return $this->json_error('Invalid version specified.');
		}

		if (!isset($http_data['type']) || !isset($http_data['arg'])) {
			return $this->json_error('No request type/data specified.');
		}
		if (!in_array($http_data['type'], self::$exposed_methods)) {
			return $this->json_error('Incorrect request type specified.');
		}

		if (isset($http_data['search_by']) && !isset($http_data['by'])) {
			$http_data['by'] = $http_data['search_by'];
		}
		if (isset($http_data['by']) && !in_array($http_data['by'], self::$exposed_fields)) {
			return $this->json_error('Incorrect by field specified.');
		}

		$this->dbh = DB::connect();

		if ($this->check_ratelimit($_SERVER['REMOTE_ADDR'])) {
			header("HTTP/1.1 429 Too Many Requests");
			return $this->json_error('Rate limit reached');
		}

		$type = str_replace('-', '_', $http_data['type']);
		if ($type == 'info' && $this->version >= 5) {
			$type = 'multiinfo';
		}
		$json = call_user_func(array(&$this, $type), $http_data);

		$etag = md5($json);
		header("Etag: \"$etag\"");
		/*
		 * Make sure to strip a few things off the
		 * if-none-match header. Stripping whitespace may not
		 * be required, but removing the quote on the incoming
		 * header is required to make the equality test.
		 */
		$if_none_match = isset($_SERVER['HTTP_IF_NONE_MATCH']) ?
			trim($_SERVER['HTTP_IF_NONE_MATCH'], "\t\n\r\" ") : false;
		if ($if_none_match && $if_none_match == $etag) {
			header('HTTP/1.1 304 Not Modified');
			return;
		}

		if (isset($http_data['callback'])) {
			$callback = $http_data['callback'];
			if (!preg_match('/^[a-zA-Z0-9()_.]{1,128}$/D', $callback)) {
				return $this->json_error('Invalid callback name.');
			}
			header('content-type: text/javascript');
			return '/**/' . $callback . '(' . $json . ')';
		} else {
			header('content-type: application/json');
			return $json;
		}
	}

	/*
	 * Check if an IP needs to be  rate limited.
	 *
	 * @param $ip IP of the current request
	 *
	 * @return true if IP needs to be rate limited, false otherwise.
	 */
	private function check_ratelimit($ip) {
		$limit = config_get("ratelimit", "request_limit");
		if ($limit == 0) {
			return false;
		}

		$this->update_ratelimit($ip);

		$status = false;
		$value = get_cache_value('ratelimit:' . $ip, $status);
		if (!$status) {
			$stmt = $this->dbh->prepare("
				SELECT Requests FROM ApiRateLimit
				WHERE IP = :ip");
			$stmt->bindParam(":ip", $ip);
			$result = $stmt->execute();

			if (!$result) {
				return false;
			}

			$row = $stmt->fetch(PDO::FETCH_ASSOC);
			$value = $row['Requests'];
		}

		return $value > $limit;
	}

	/*
	 * Update a rate limit for an IP by increasing it's requests value by one.
	 *
	 * @param $ip IP of the current request
	 *
	 * @return void
	 */
	private function update_ratelimit($ip) {
		$window_length = config_get("ratelimit", "window_length");
		$db_backend = config_get("database", "backend");
		$time = time();
		$deletion_time = $time - $window_length;

		/* Try to use the cache. */
		$status = false;
		$value = get_cache_value('ratelimit-ws:' . $ip, $status);
		if (!$status || ($status && $value < $deletion_time)) {
			if (set_cache_value('ratelimit-ws:' . $ip, $time, $window_length) &&
			    set_cache_value('ratelimit:' . $ip, 1, $window_length)) {
				return;
			}
		} else {
			$value = get_cache_value('ratelimit:' . $ip, $status);
			if ($status && set_cache_value('ratelimit:' . $ip, $value + 1, $window_length))
				return;
		}

		/* Clean up old windows. */
		$stmt = $this->dbh->prepare("
			DELETE FROM ApiRateLimit
			WHERE WindowStart < :time");
		$stmt->bindParam(":time", $deletion_time);
		$stmt->execute();

		if ($db_backend == "mysql") {
			$stmt = $this->dbh->prepare("
				INSERT INTO ApiRateLimit
				(IP, Requests, WindowStart)
				VALUES (:ip, 1, :window_start)
				ON DUPLICATE KEY UPDATE Requests=Requests+1");
			$stmt->bindParam(":ip", $ip);
			$stmt->bindParam(":window_start", $time);
			$stmt->execute();
		} elseif ($db_backend == "sqlite") {
			$stmt = $this->dbh->prepare("
				INSERT OR IGNORE INTO ApiRateLimit
				(IP, Requests, WindowStart)
				VALUES (:ip, 0, :window_start);");
			$stmt->bindParam(":ip", $ip);
			$stmt->bindParam(":window_start", $time);
			$stmt->execute();

			$stmt = $this->dbh->prepare("
				UPDATE ApiRateLimit
				SET Requests = Requests + 1
				WHERE IP = :ip");
			$stmt->bindParam(":ip", $ip);
			$stmt->execute();
		} else {
			throw new RuntimeException("Unknown database backend");
		}
	}

	/*
	 * Returns a JSON formatted error string.
	 *
	 * @param $msg The error string to return
	 *
	 * @return mixed A json formatted error response.
	 */
	private function json_error($msg) {
		header('content-type: application/json');
		if ($this->version < 3) {
			return $this->json_results('error', 0, $msg, NULL);
		} elseif ($this->version >= 3) {
			return $this->json_results('error', 0, array(), $msg);
		}
	}

	/*
	 * Returns a JSON formatted result data.
	 *
	 * @param $type The response method type.
	 * @param $count The number of results to return
	 * @param $data The result data to return
	 * @param $error An error message to include in the response
	 *
	 * @return mixed A json formatted result response.
	 */
	private function json_results($type, $count, $data, $error) {
		$json_array = array(
			'version' => $this->version,
			'type' => $type,
			'resultcount' => $count,
			'results' => $data
		);

		if ($error) {
			$json_array['error'] = $error;
		}

		return json_encode($json_array);
	}

	/*
	 * Get extended package details (for info and multiinfo queries).
	 *
	 * @param $pkgid The ID of the package to retrieve details for.
	 * @param $base_id The ID of the package base to retrieve details for.
	 *
	 * @return array An array containing package details.
	 */
	private function get_extended_fields($pkgid, $base_id) {
		$query = "SELECT DependencyTypes.Name AS Type, " .
			"PackageDepends.DepName AS Name, " .
			"PackageDepends.DepCondition AS Cond " .
			"FROM PackageDepends " .
			"LEFT JOIN DependencyTypes " .
			"ON DependencyTypes.ID = PackageDepends.DepTypeID " .
			"WHERE PackageDepends.PackageID = " . $pkgid . " " .
			"UNION SELECT RelationTypes.Name AS Type, " .
			"PackageRelations.RelName AS Name, " .
			"PackageRelations.RelCondition AS Cond " .
			"FROM PackageRelations " .
			"LEFT JOIN RelationTypes " .
			"ON RelationTypes.ID = PackageRelations.RelTypeID " .
			"WHERE PackageRelations.PackageID = " . $pkgid . " " .
			"UNION SELECT 'groups' AS Type, `Groups`.`Name`, '' AS Cond " .
			"FROM `Groups` INNER JOIN PackageGroups " .
			"ON PackageGroups.PackageID = " . $pkgid . " " .
			"AND PackageGroups.GroupID = `Groups`.ID " .
			"UNION SELECT 'license' AS Type, Licenses.Name, '' AS Cond " .
			"FROM Licenses INNER JOIN PackageLicenses " .
			"ON PackageLicenses.PackageID = " . $pkgid . " " .
			"AND PackageLicenses.LicenseID = Licenses.ID";
		$ttl = config_get_int('options', 'cache_pkginfo_ttl');
		$rows = db_cache_result($query, 'extended-fields:' . $pkgid, PDO::FETCH_ASSOC, $ttl);

		$type_map = array(
			'depends' => 'Depends',
			'makedepends' => 'MakeDepends',
			'checkdepends' => 'CheckDepends',
			'optdepends' => 'OptDepends',
			'conflicts' => 'Conflicts',
			'provides' => 'Provides',
			'replaces' => 'Replaces',
			'groups' => 'Groups',
			'license' => 'License',
		);
		$data = array();
		foreach ($rows as $row) {
			$type = $type_map[$row['Type']];
			$data[$type][] = $row['Name'] . $row['Cond'];
		}

		if ($this->version >= 5) {
			$query = "SELECT Keyword FROM PackageKeywords " .
				"WHERE PackageBaseID = " . intval($base_id) . " " .
				"ORDER BY Keyword ASC";
			$ttl = config_get_int('options', 'cache_pkginfo_ttl');
			$rows = db_cache_result($query, 'keywords:' . intval($base_id), PDO::FETCH_NUM, $ttl);
			$data['Keywords'] = array_map(function ($x) { return $x[0]; }, $rows);
		}

		return $data;
	}

	/*
	 * Retrieve package information (used in info, multiinfo, search and
	 * depends requests).
	 *
	 * @param $type The request type.
	 * @param $where_condition An SQL WHERE-condition to filter packages.
	 *
	 * @return mixed Returns an array of package matches.
	 */
	private function process_query($type, $where_condition) {
		$max_results = config_get_int('options', 'max_rpc_results');

		if ($this->version == 1) {
			$fields = implode(',', self::$fields_v1);
			$query = "SELECT {$fields} " .
				"FROM Packages LEFT JOIN PackageBases " .
				"ON PackageBases.ID = Packages.PackageBaseID " .
				"LEFT JOIN Users " .
				"ON PackageBases.MaintainerUID = Users.ID " .
				"LEFT JOIN PackageLicenses " .
				"ON PackageLicenses.PackageID = Packages.ID " .
				"LEFT JOIN Licenses " .
				"ON Licenses.ID = PackageLicenses.LicenseID " .
				"WHERE ${where_condition} " .
				"AND PackageBases.PackagerUID IS NOT NULL " .
				"LIMIT $max_results";
		} elseif ($this->version >= 2) {
			if ($this->version == 2 || $this->version == 3) {
				$fields = implode(',', self::$fields_v2);
			} else if ($this->version == 4 || $this->version == 5) {
				$fields = implode(',', self::$fields_v4);
			}
			$query = "SELECT {$fields} " .
				"FROM Packages LEFT JOIN PackageBases " .
				"ON PackageBases.ID = Packages.PackageBaseID " .
				"LEFT JOIN Users " .
				"ON PackageBases.MaintainerUID = Users.ID " .
				"WHERE ${where_condition} " .
				"AND PackageBases.PackagerUID IS NOT NULL " .
				"LIMIT $max_results";
		}
		$result = $this->dbh->query($query);

		if ($result) {
			$resultcount = 0;
			$search_data = array();
			while ($row = $result->fetch(PDO::FETCH_ASSOC)) {
				$resultcount++;
				$row['URLPath'] = sprintf(config_get('options', 'snapshot_uri'), urlencode($row['PackageBase']));
				if ($this->version < 4) {
					$row['CategoryID'] = 1;
				}

				/*
				 * Unfortunately, mysql_fetch_assoc() returns
				 * all fields as strings. We need to coerce
				 * numeric values into integers to provide
				 * proper data types in the JSON response.
				 */
				foreach (self::$numeric_fields as $field) {
					if (isset($row[$field])) {
						$row[$field] = intval($row[$field]);
					}
				}

				foreach (self::$decimal_fields as $field) {
					if (isset($row[$field])) {
						$row[$field] = floatval($row[$field]);
					}
				}

				if ($this->version >= 2 && ($type == 'info' || $type == 'multiinfo')) {
					$extfields = $this->get_extended_fields($row['ID'], $row['PackageBaseID']);
					if ($extfields) {
						$row = array_merge($row, $extfields);
					}
				}

				if ($this->version < 3) {
					if ($type == 'info') {
						$search_data = $row;
						break;
					} else {
						array_push($search_data, $row);
					}
				} elseif ($this->version >= 3) {
					array_push($search_data, $row);
				}
			}

			if ($resultcount === $max_results) {
				return $this->json_error('Too many package results.');
			}

			return $this->json_results($type, $resultcount, $search_data, NULL);
		} else {
			return $this->json_results($type, 0, array(), NULL);
		}
	}

	/*
	 * Parse the args to the multiinfo function. We may have a string or an
	 * array, so do the appropriate thing. Within the elements, both * package
	 * IDs and package names are valid; sort them into the relevant arrays and
	 * escape/quote the names.
	 *
	 * @param array $args Query parameters.
	 *
	 * @return mixed An array containing 'ids' and 'names'.
	 */
	private function parse_multiinfo_args($args) {
		if (!is_array($args)) {
			$args = array($args);
		}

		$id_args = array();
		$name_args = array();
		foreach ($args as $arg) {
			if (!$arg) {
				continue;
			}
			if ($this->version < 5 && is_numeric($arg)) {
				$id_args[] = intval($arg);
			} else {
				$name_args[] = $this->dbh->quote($arg);
			}
		}

		return array('ids' => $id_args, 'names' => $name_args);
	}

	/*
	 * Performs a fulltext mysql search of the package database.
	 *
	 * @param array $http_data Query parameters.
	 *
	 * @return mixed Returns an array of package matches.
	 */
	private function search($http_data) {
		$keyword_string = $http_data['arg'];

		if (isset($http_data['by'])) {
			$search_by = $http_data['by'];
		} else {
			$search_by = 'name-desc';
		}

		if ($search_by === 'name' || $search_by === 'name-desc') {
			if (strlen($keyword_string) < 2) {
				return $this->json_error('Query arg too small.');
			}
			$keyword_string = $this->dbh->quote("%" . addcslashes($keyword_string, '%_') . "%");

			if ($search_by === 'name') {
				$where_condition = "(Packages.Name LIKE $keyword_string)";
			} else if ($search_by === 'name-desc') {
				$where_condition = "(Packages.Name LIKE $keyword_string OR ";
				$where_condition .= "Description LIKE $keyword_string)";
			}
		} else if ($search_by === 'maintainer') {
			if (empty($keyword_string)) {
				$where_condition = "Users.ID is NULL";
			} else {
				$keyword_string = $this->dbh->quote($keyword_string);
				$where_condition = "Users.Username = $keyword_string ";
			}
		} else if (in_array($search_by, self::$exposed_depfields)) {
			if (empty($keyword_string)) {
				return $this->json_error('Query arg is empty.');
			} else {
				$keyword_string = $this->dbh->quote($keyword_string);
				$search_by = $this->dbh->quote($search_by);
				$subquery = "SELECT PackageDepends.DepName FROM PackageDepends ";
				$subquery .= "LEFT JOIN DependencyTypes ";
				$subquery .= "ON PackageDepends.DepTypeID = DependencyTypes.ID ";
				$subquery .= "WHERE PackageDepends.PackageID = Packages.ID ";
				$subquery .= "AND DependencyTypes.Name = $search_by";
				$where_condition = "$keyword_string IN ($subquery)";
			}
		}

		return $this->process_query('search', $where_condition);
	}

	/*
	 * Returns the info on a specific package.
	 *
	 * @param array $http_data Query parameters.
	 *
	 * @return mixed Returns an array of value data containing the package data
	 */
	private function info($http_data) {
		$pqdata = $http_data['arg'];
		if ($this->version < 5 && is_numeric($pqdata)) {
			$where_condition = "Packages.ID = $pqdata";
		} else {
			$where_condition = "Packages.Name = " . $this->dbh->quote($pqdata);
		}

		return $this->process_query('info', $where_condition);
	}

	/*
	 * Returns the info on multiple packages.
	 *
	 * @param array $http_data Query parameters.
	 *
	 * @return mixed Returns an array of results containing the package data
	 */
	private function multiinfo($http_data) {
		$pqdata = $http_data['arg'];
		$args = $this->parse_multiinfo_args($pqdata);
		$ids = $args['ids'];
		$names = $args['names'];

		if (!$ids && !$names) {
			return $this->json_error('Invalid query arguments.');
		}

		$where_condition = "";
		if ($ids) {
			$ids_value = implode(',', $args['ids']);
			$where_condition .= "Packages.ID IN ($ids_value) ";
		}
		if ($ids && $names) {
			$where_condition .= "OR ";
		}
		if ($names) {
			/*
			 * Individual names were quoted in
			 * parse_multiinfo_args().
			 */
			$names_value = implode(',', $args['names']);
			$where_condition .= "Packages.Name IN ($names_value) ";
		}

		return $this->process_query('multiinfo', $where_condition);
	}

	/*
	 * Returns all the packages for a specific maintainer.
	 *
	 * @param array $http_data Query parameters.
	 *
	 * @return mixed Returns an array of value data containing the package data
	 */
	private function msearch($http_data) {
		$http_data['by'] = 'maintainer';
		return $this->search($http_data);
	}

	/*
	 * Get all package names that start with $search.
	 *
	 * @param array $http_data Query parameters.
	 *
	 * @return string The JSON formatted response data.
	 */
	private function suggest($http_data) {
		$search = $http_data['arg'];
		$query = "SELECT Packages.Name FROM Packages ";
		$query.= "LEFT JOIN PackageBases ";
		$query.= "ON PackageBases.ID = Packages.PackageBaseID ";
		$query.= "WHERE Packages.Name LIKE ";
		$query.= $this->dbh->quote(addcslashes($search, '%_') . '%');
		$query.= " AND PackageBases.PackagerUID IS NOT NULL ";
		$query.= "ORDER BY Name ASC LIMIT 20";

		$result = $this->dbh->query($query);
		$result_array = array();

		if ($result) {
			$result_array = $result->fetchAll(PDO::FETCH_COLUMN, 0);
		}

		return json_encode($result_array);
	}

	/*
	 * Get all package base names that start with $search.
	 *
	 * @param array $http_data Query parameters.
	 *
	 * @return string The JSON formatted response data.
	 */
	private function suggest_pkgbase($http_data) {
		$search = $http_data['arg'];
		$query = "SELECT Name FROM PackageBases WHERE Name LIKE ";
		$query.= $this->dbh->quote(addcslashes($search, '%_') . '%');
		$query.= " AND PackageBases.PackagerUID IS NOT NULL ";
		$query.= "ORDER BY Name ASC LIMIT 20";

		$result = $this->dbh->query($query);
		$result_array = array();

		if ($result) {
			$result_array = $result->fetchAll(PDO::FETCH_COLUMN, 0);
		}

		return json_encode($result_array);
	}

	/**
	 * Get the HTML markup of the comment form.
	 *
	 * @param array $http_data Query parameters.
	 *
	 * @return string The JSON formatted response data.
	 */
	private function get_comment_form($http_data) {
		if (!isset($http_data['base_id']) || !isset($http_data['pkgbase_name'])) {
			$output = array(
				'success' => 0,
				'error' => __('Package base ID or package base name missing.')
			);
			return json_encode($output);
		}

		$comment_id = intval($http_data['arg']);
		$base_id = intval($http_data['base_id']);
		$pkgbase_name = $http_data['pkgbase_name'];

		list($user_id, $comment) = comment_by_id($comment_id);

		if (!has_credential(CRED_COMMENT_EDIT, array($user_id))) {
			$output = array(
				'success' => 0,
				'error' => __('You are not allowed to edit this comment.')
			);
			return json_encode($output);
		} elseif (is_null($comment)) {
			$output = array(
				'success' => 0,
				'error' => __('Comment does not exist.')
			);
			return json_encode($output);
		}

		ob_start();
		include('pkg_comment_form.php');
		$html = ob_get_clean();
		$output = array(
			'success' => 1,
			'form' => $html
		);

		return json_encode($output);
	}
}