3 * Job queue task base code.
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6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License along
16 * with this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
18 * http://www.gnu.org/copyleft/gpl.html
21 * @defgroup JobQueue JobQueue
25 * Class to both describe a background job and handle jobs.
26 * The queue aspects of this class are now deprecated.
27 * Using the class to push jobs onto queues is deprecated (use JobSpecification).
31 abstract class Job
implements IJobSpecification
{
35 /** @var array Array of job parameters */
38 /** @var array Additional queue metadata */
39 public $metadata = [];
44 /** @var bool Expensive jobs may set this to true */
45 protected $removeDuplicates;
47 /** @var string Text for error that occurred last */
50 /** @var callable[] */
51 protected $teardownCallbacks = [];
53 /** @var int Bitfield of JOB_* class constants */
54 protected $executionFlags = 0;
56 /** @var int Job must not be wrapped in the usual explicit LBFactory transaction round */
57 const JOB_NO_EXPLICIT_TRX_ROUND
= 1;
61 * @return bool Success
63 abstract public function run();
66 * Create the appropriate object to handle a specific job
68 * @param string $command Job command
69 * @param Title $title Associated title
70 * @param array $params Job parameters
74 public static function factory( $command, Title
$title, $params = [] ) {
77 if ( isset( $wgJobClasses[$command] ) ) {
78 $handler = $wgJobClasses[$command];
80 if ( is_callable( $handler ) ) {
81 $job = call_user_func( $handler, $title, $params );
82 } elseif ( class_exists( $handler ) ) {
83 $job = new $handler( $title, $params );
88 if ( $job instanceof Job
) {
89 $job->command
= $command;
92 throw new InvalidArgumentException( "Cannot instantiate job '$command': bad spec!" );
96 throw new InvalidArgumentException( "Invalid job command '{$command}'" );
100 * @param string $command
101 * @param Title $title
102 * @param array|bool $params Can not be === true
104 public function __construct( $command, $title, $params = false ) {
105 $this->command
= $command;
106 $this->title
= $title;
107 $this->params
= is_array( $params ) ?
$params : []; // sanity
109 // expensive jobs may set this to true
110 $this->removeDuplicates
= false;
112 if ( !isset( $this->params
['requestId'] ) ) {
113 $this->params
['requestId'] = WebRequest
::getRequestId();
118 * @param int $flag JOB_* class constant
122 public function hasExecutionFlag( $flag ) {
123 return ( $this->executionFlags
&& $flag ) === $flag;
127 * Batch-insert a group of jobs into the queue.
128 * This will be wrapped in a transaction with a forced commit.
130 * This may add duplicate at insert time, but they will be
131 * removed later on, when the first one is popped.
133 * @param Job[] $jobs Array of Job objects
135 * @deprecated since 1.21
137 public static function batchInsert( $jobs ) {
138 wfDeprecated( __METHOD__
, '1.21' );
139 JobQueueGroup
::singleton()->push( $jobs );
146 public function getType() {
147 return $this->command
;
153 public function getTitle() {
160 public function getParams() {
161 return $this->params
;
165 * @return int|null UNIX timestamp to delay running this job until, otherwise null
168 public function getReleaseTimestamp() {
169 return isset( $this->params
['jobReleaseTimestamp'] )
170 ?
wfTimestampOrNull( TS_UNIX
, $this->params
['jobReleaseTimestamp'] )
175 * @return int|null UNIX timestamp of when the job was queued, or null
178 public function getQueuedTimestamp() {
179 return isset( $this->metadata
['timestamp'] )
180 ?
wfTimestampOrNull( TS_UNIX
, $this->metadata
['timestamp'] )
185 * @return string|null Id of the request that created this job. Follows
186 * jobs recursively, allowing to track the id of the request that started a
187 * job when jobs insert jobs which insert other jobs.
190 public function getRequestId() {
191 return isset( $this->params
['requestId'] )
192 ?
$this->params
['requestId']
197 * @return int|null UNIX timestamp of when the job was runnable, or null
200 public function getReadyTimestamp() {
201 return $this->getReleaseTimestamp() ?
: $this->getQueuedTimestamp();
205 * Whether the queue should reject insertion of this job if a duplicate exists
207 * This can be used to avoid duplicated effort or combined with delayed jobs to
208 * coalesce updates into larger batches. Claimed jobs are never treated as
209 * duplicates of new jobs, and some queues may allow a few duplicates due to
210 * network partitions and fail-over. Thus, additional locking is needed to
211 * enforce mutual exclusion if this is really needed.
215 public function ignoreDuplicates() {
216 return $this->removeDuplicates
;
220 * @return bool Whether this job can be retried on failure by job runners
223 public function allowRetries() {
228 * @return int Number of actually "work items" handled in this job
229 * @see $wgJobBackoffThrottling
232 public function workItemCount() {
237 * Subclasses may need to override this to make duplication detection work.
238 * The resulting map conveys everything that makes the job unique. This is
239 * only checked if ignoreDuplicates() returns true, meaning that duplicate
240 * jobs are supposed to be ignored.
242 * @return array Map of key/values
245 public function getDeduplicationInfo() {
247 'type' => $this->getType(),
248 'namespace' => $this->getTitle()->getNamespace(),
249 'title' => $this->getTitle()->getDBkey(),
250 'params' => $this->getParams()
252 if ( is_array( $info['params'] ) ) {
253 // Identical jobs with different "root" jobs should count as duplicates
254 unset( $info['params']['rootJobSignature'] );
255 unset( $info['params']['rootJobTimestamp'] );
256 // Likewise for jobs with different delay times
257 unset( $info['params']['jobReleaseTimestamp'] );
258 // Identical jobs from different requests should count as duplicates
259 unset( $info['params']['requestId'] );
260 // Queues pack and hash this array, so normalize the order
261 ksort( $info['params'] );
268 * Get "root job" parameters for a task
270 * This is used to no-op redundant jobs, including child jobs of jobs,
271 * as long as the children inherit the root job parameters. When a job
272 * with root job parameters and "rootJobIsSelf" set is pushed, the
273 * deduplicateRootJob() method is automatically called on it. If the
274 * root job is only virtual and not actually pushed (e.g. the sub-jobs
275 * are inserted directly), then call deduplicateRootJob() directly.
277 * @see JobQueue::deduplicateRootJob()
279 * @param string $key A key that identifies the task
280 * @return array Map of:
281 * - rootJobIsSelf : true
282 * - rootJobSignature : hash (e.g. SHA1) that identifies the task
283 * - rootJobTimestamp : TS_MW timestamp of this instance of the task
286 public static function newRootJobParams( $key ) {
288 'rootJobIsSelf' => true,
289 'rootJobSignature' => sha1( $key ),
290 'rootJobTimestamp' => wfTimestampNow()
295 * @see JobQueue::deduplicateRootJob()
299 public function getRootJobParams() {
301 'rootJobSignature' => isset( $this->params
['rootJobSignature'] )
302 ?
$this->params
['rootJobSignature']
304 'rootJobTimestamp' => isset( $this->params
['rootJobTimestamp'] )
305 ?
$this->params
['rootJobTimestamp']
311 * @see JobQueue::deduplicateRootJob()
315 public function hasRootJobParams() {
316 return isset( $this->params
['rootJobSignature'] )
317 && isset( $this->params
['rootJobTimestamp'] );
321 * @see JobQueue::deduplicateRootJob()
322 * @return bool Whether this is job is a root job
324 public function isRootJob() {
325 return $this->hasRootJobParams() && !empty( $this->params
['rootJobIsSelf'] );
329 * @param callable $callback A function with one parameter, the success status, which will be
330 * false if the job failed or it succeeded but the DB changes could not be committed or
331 * any deferred updates threw an exception. (This parameter was added in 1.28.)
334 protected function addTeardownCallback( $callback ) {
335 $this->teardownCallbacks
[] = $callback;
339 * Do any final cleanup after run(), deferred updates, and all DB commits happen
340 * @param bool $status Whether the job, its deferred updates, and DB commit all succeeded
343 public function teardown( $status ) {
344 foreach ( $this->teardownCallbacks
as $callback ) {
345 call_user_func( $callback, $status );
350 * Insert a single job into the queue.
351 * @return bool True on success
352 * @deprecated since 1.21
354 public function insert() {
355 wfDeprecated( __METHOD__
, '1.21' );
356 JobQueueGroup
::singleton()->push( $this );
363 public function toString() {
365 if ( $this->params
) {
366 foreach ( $this->params
as $key => $value ) {
367 if ( $paramString != '' ) {
370 if ( is_array( $value ) ) {
372 foreach ( $value as $k => $v ) {
373 $json = FormatJson
::encode( $v );
374 if ( $json === false ||
mb_strlen( $json ) > 512 ) {
375 $filteredValue[$k] = gettype( $v ) . '(...)';
377 $filteredValue[$k] = $v;
380 if ( count( $filteredValue ) <= 10 ) {
381 $value = FormatJson
::encode( $filteredValue );
383 $value = "array(" . count( $value ) . ")";
385 } elseif ( is_object( $value ) && !method_exists( $value, '__toString' ) ) {
386 $value = "object(" . get_class( $value ) . ")";
389 $flatValue = (string)$value;
390 if ( mb_strlen( $value ) > 1024 ) {
391 $flatValue = "string(" . mb_strlen( $value ) . ")";
394 $paramString .= "$key={$flatValue}";
399 foreach ( $this->metadata
as $key => $value ) {
400 if ( is_scalar( $value ) && mb_strlen( $value ) < 1024 ) {
401 $metaString .= ( $metaString ?
",$key=$value" : "$key=$value" );
406 if ( is_object( $this->title
) ) {
407 $s .= " {$this->title->getPrefixedDBkey()}";
409 if ( $paramString != '' ) {
410 $s .= " $paramString";
412 if ( $metaString != '' ) {
413 $s .= " ($metaString)";
419 protected function setLastError( $error ) {
420 $this->error
= $error;
423 public function getLastError() {