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.
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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 * To push jobs onto queues, use JobQueueGroup::singleton()->push();
30 abstract class Job
implements RunnableJob
{
34 /** @var array Array of job parameters */
37 /** @var array Additional queue metadata */
38 public $metadata = [];
43 /** @var bool Expensive jobs may set this to true */
44 protected $removeDuplicates = false;
46 /** @var string Text for error that occurred last */
49 /** @var callable[] */
50 protected $teardownCallbacks = [];
52 /** @var int Bitfield of JOB_* class constants */
53 protected $executionFlags = 0;
55 /** @var int Job must not be wrapped in the usual explicit LBFactory transaction round */
56 const JOB_NO_EXPLICIT_TRX_ROUND
= 1;
59 * Create the appropriate object to handle a specific job
61 * @param string $command Job command
62 * @param array|Title $params Job parameters
63 * @throws InvalidArgumentException
66 public static function factory( $command, $params = [] ) {
69 if ( $params instanceof Title
) {
70 // Backwards compatibility for old signature ($command, $title, $params)
72 $params = func_num_args() >= 3 ?
func_get_arg( 2 ) : [];
74 $title = ( isset( $params['namespace'] ) && isset( $params['title'] ) )
75 ? Title
::makeTitle( $params['namespace'], $params['title'] )
76 : Title
::makeTitle( NS_SPECIAL
, '' );
79 $params = is_array( $params ) ?
$params : []; // sanity
81 if ( isset( $wgJobClasses[$command] ) ) {
82 $handler = $wgJobClasses[$command];
84 if ( is_callable( $handler ) ) {
85 $job = call_user_func( $handler, $title, $params );
86 } elseif ( class_exists( $handler ) ) {
87 if ( is_subclass_of( $handler, GenericParameterJob
::class ) ) {
88 $job = new $handler( $params );
90 $job = new $handler( $title, $params );
96 if ( $job instanceof Job
) {
97 $job->command
= $command;
101 throw new InvalidArgumentException( "Could instantiate job '$command': bad spec!" );
105 throw new InvalidArgumentException( "Invalid job command '{$command}'" );
109 * @param string $command
110 * @param array|Title|null $params
112 public function __construct( $command, $params = null ) {
113 if ( $params instanceof Title
) {
114 // Backwards compatibility for old signature ($command, $title, $params)
116 $params = func_num_args() >= 3 ?
func_get_arg( 2 ) : [];
117 $params = is_array( $params ) ?
$params : []; // sanity
118 // Set namespace/title params if both are missing and this is not a dummy title
120 $title->getDBkey() !== '' &&
121 !isset( $params['namespace'] ) &&
122 !isset( $params['title'] )
124 $params['namespace'] = $title->getNamespace();
125 $params['title'] = $title->getDBKey();
126 // Note that JobQueue classes will prefer the parameters over getTitle()
127 $this->title
= $title;
131 $this->command
= $command;
132 $this->params
= $params +
[ 'requestId' => WebRequest
::getRequestId() ];
133 if ( $this->title
=== null ) {
134 $this->title
= ( isset( $params['namespace'] ) && isset( $params['title'] ) )
135 ? Title
::makeTitle( $params['namespace'], $params['title'] )
136 : Title
::makeTitle( NS_SPECIAL
, '' );
141 * @param int $flag JOB_* class constant
145 public function hasExecutionFlag( $flag ) {
146 return ( $this->executionFlags
& $flag ) === $flag;
152 public function getType() {
153 return $this->command
;
159 final public function getTitle() {
166 public function getParams() {
167 return $this->params
;
171 * @param string|null $field Metadata field or null to get all the metadata
172 * @return mixed|null Value; null if missing
175 public function getMetadata( $field = null ) {
176 if ( $field === null ) {
177 return $this->metadata
;
180 return $this->metadata
[$field] ??
null;
184 * @param string $field Key name to set the value for
185 * @param mixed $value The value to set the field for
186 * @return mixed|null The prior field value; null if missing
189 public function setMetadata( $field, $value ) {
190 $old = $this->getMetadata( $field );
191 if ( $value === null ) {
192 unset( $this->metadata
[$field] );
194 $this->metadata
[$field] = $value;
201 * @return int|null UNIX timestamp to delay running this job until, otherwise null
204 public function getReleaseTimestamp() {
205 return isset( $this->params
['jobReleaseTimestamp'] )
206 ?
wfTimestampOrNull( TS_UNIX
, $this->params
['jobReleaseTimestamp'] )
211 * @return int|null UNIX timestamp of when the job was queued, or null
214 public function getQueuedTimestamp() {
215 return isset( $this->metadata
['timestamp'] )
216 ?
wfTimestampOrNull( TS_UNIX
, $this->metadata
['timestamp'] )
221 * @return string|null Id of the request that created this job. Follows
222 * jobs recursively, allowing to track the id of the request that started a
223 * job when jobs insert jobs which insert other jobs.
226 public function getRequestId() {
227 return $this->params
['requestId'] ??
null;
231 * @return int|null UNIX timestamp of when the job was runnable, or null
234 public function getReadyTimestamp() {
235 return $this->getReleaseTimestamp() ?
: $this->getQueuedTimestamp();
239 * Whether the queue should reject insertion of this job if a duplicate exists
241 * This can be used to avoid duplicated effort or combined with delayed jobs to
242 * coalesce updates into larger batches. Claimed jobs are never treated as
243 * duplicates of new jobs, and some queues may allow a few duplicates due to
244 * network partitions and fail-over. Thus, additional locking is needed to
245 * enforce mutual exclusion if this is really needed.
249 public function ignoreDuplicates() {
250 return $this->removeDuplicates
;
254 * @return bool Whether this job can be retried on failure by job runners
257 public function allowRetries() {
262 * @return int Number of actually "work items" handled in this job
263 * @see $wgJobBackoffThrottling
266 public function workItemCount() {
271 * Subclasses may need to override this to make duplication detection work.
272 * The resulting map conveys everything that makes the job unique. This is
273 * only checked if ignoreDuplicates() returns true, meaning that duplicate
274 * jobs are supposed to be ignored.
276 * @return array Map of key/values
279 public function getDeduplicationInfo() {
281 'type' => $this->getType(),
282 'params' => $this->getParams()
284 if ( is_array( $info['params'] ) ) {
285 // Identical jobs with different "root" jobs should count as duplicates
286 unset( $info['params']['rootJobSignature'] );
287 unset( $info['params']['rootJobTimestamp'] );
288 // Likewise for jobs with different delay times
289 unset( $info['params']['jobReleaseTimestamp'] );
290 // Identical jobs from different requests should count as duplicates
291 unset( $info['params']['requestId'] );
292 // Queues pack and hash this array, so normalize the order
293 ksort( $info['params'] );
300 * Get "root job" parameters for a task
302 * This is used to no-op redundant jobs, including child jobs of jobs,
303 * as long as the children inherit the root job parameters. When a job
304 * with root job parameters and "rootJobIsSelf" set is pushed, the
305 * deduplicateRootJob() method is automatically called on it. If the
306 * root job is only virtual and not actually pushed (e.g. the sub-jobs
307 * are inserted directly), then call deduplicateRootJob() directly.
309 * @see JobQueue::deduplicateRootJob()
311 * @param string $key A key that identifies the task
312 * @return array Map of:
313 * - rootJobIsSelf : true
314 * - rootJobSignature : hash (e.g. SHA1) that identifies the task
315 * - rootJobTimestamp : TS_MW timestamp of this instance of the task
318 public static function newRootJobParams( $key ) {
320 'rootJobIsSelf' => true,
321 'rootJobSignature' => sha1( $key ),
322 'rootJobTimestamp' => wfTimestampNow()
327 * @see JobQueue::deduplicateRootJob()
331 public function getRootJobParams() {
333 'rootJobSignature' => $this->params
['rootJobSignature'] ??
null,
334 'rootJobTimestamp' => $this->params
['rootJobTimestamp'] ??
null
339 * @see JobQueue::deduplicateRootJob()
343 public function hasRootJobParams() {
344 return isset( $this->params
['rootJobSignature'] )
345 && isset( $this->params
['rootJobTimestamp'] );
349 * @see JobQueue::deduplicateRootJob()
350 * @return bool Whether this is job is a root job
352 public function isRootJob() {
353 return $this->hasRootJobParams() && !empty( $this->params
['rootJobIsSelf'] );
357 * @param callable $callback A function with one parameter, the success status, which will be
358 * false if the job failed or it succeeded but the DB changes could not be committed or
359 * any deferred updates threw an exception. (This parameter was added in 1.28.)
362 protected function addTeardownCallback( $callback ) {
363 $this->teardownCallbacks
[] = $callback;
367 * Do any final cleanup after run(), deferred updates, and all DB commits happen
368 * @param bool $status Whether the job, its deferred updates, and DB commit all succeeded
371 public function teardown( $status ) {
372 foreach ( $this->teardownCallbacks
as $callback ) {
373 call_user_func( $callback, $status );
380 public function toString() {
382 if ( $this->params
) {
383 foreach ( $this->params
as $key => $value ) {
384 if ( $paramString != '' ) {
387 if ( is_array( $value ) ) {
389 foreach ( $value as $k => $v ) {
390 $json = FormatJson
::encode( $v );
391 if ( $json === false ||
mb_strlen( $json ) > 512 ) {
392 $filteredValue[$k] = gettype( $v ) . '(...)';
394 $filteredValue[$k] = $v;
397 if ( count( $filteredValue ) <= 10 ) {
398 $value = FormatJson
::encode( $filteredValue );
400 $value = "array(" . count( $value ) . ")";
402 } elseif ( is_object( $value ) && !method_exists( $value, '__toString' ) ) {
403 $value = "object(" . get_class( $value ) . ")";
406 $flatValue = (string)$value;
407 if ( mb_strlen( $value ) > 1024 ) {
408 $flatValue = "string(" . mb_strlen( $value ) . ")";
411 $paramString .= "$key={$flatValue}";
416 foreach ( $this->metadata
as $key => $value ) {
417 if ( is_scalar( $value ) && mb_strlen( $value ) < 1024 ) {
418 $metaString .= ( $metaString ?
",$key=$value" : "$key=$value" );
423 if ( is_object( $this->title
) ) {
424 $s .= " {$this->title->getPrefixedDBkey()}";
426 if ( $paramString != '' ) {
427 $s .= " $paramString";
429 if ( $metaString != '' ) {
430 $s .= " ($metaString)";
436 protected function setLastError( $error ) {
437 $this->error
= $error;
440 public function getLastError() {