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hof:until( function($f) { jobs:finishedwait($query) }, function($f) { prof:sleep(10) }, () ),
no edit summary
|-
| '''Summary'''
|Returns information on all jobs that are currently registered. The list includes scheduled, queued, running jobs, and cached jobs. A string representation of the job , or its URI, will be returned in the text nodeas value. The returned elements have additional attributes:
* <code>id</code>: job id
* <code>type</code>: type of the job (command, query, REST, RESTXQ, etc.)
|-
| '''Summary'''
|Indicates if the evaluation of a an already running job with the specified {{Code|$id}} has finished. As the ids of finished jobs will usually be discarded, unless caching is enabled, the function will also return <code>true</code> for unknown jobs.
* <code>false</code> indicates that the job id is scheduled, queued, or currently running.
* <code>true</code> will be returned if the job has either finished, or if the id is unknown (because the ids of all finished jobs will not be cached).
|-
| '''Summary'''
|Cancels Triggeres the execution cancelation of a job with the specified {{Code|$id}}, drops the cached result of a query, or cancels a scheduled job. Unknown ids are ignored. All jobs are gracefully stopped; it is up to the process to decide when it is safe to shut down.|} ==jobs:wait== {| width='100%'|-| width='120' | '''Signatures'''|{{Func|jobs:wait|$id as xs:string|empty-sequence()}}|-| '''Summary'''|Waits for the completion of a job with the specified {{Code|$id}}:* The function will terminate immediately if the job id is unknown. This is the case if a future job has not been queued yet, or if the id has already been discarded after job evaluation.* If the function is called with the id of a queued job, or repeatedly executed job, it may stall and never terminate.|-| '''Errors'''|{{Error|self|#Errors}} if the current job is addressed.<br/>
|}
* {{Code|start}}: a dayTimeDuration, time or dateTime can be specified to delay the execution of the query:
** If a dayTimeDuration is specified, the query will be queued after the specified duration has passed. Examples for valid values are: <code>P1D</code> (1 day), <code>PT5M</code> (5 minutes), <code>PT0.1S</code> (100 ms). An error will be raised if a negative value is specified.
** If a time is specified, the query will be executed at this time of the day. Examples for valid times are: <code>02:00:00</code> (2amlocal time), <code>12:00:0000Z</code> (noon, UTC). If the time lies in the past, the query will be executed the next day.
** If a dateTime is specified, the query will be executed at this date. Examples for valid values are: <code>2018-12-31T23:59:59</code> (New Year's Eve 2018, close to midnight). An error will be raised if the specified time lies in the past.
* {{Code|interval}}: a dayTimeDuration string can be specified to execute the query periodically. An error is raised if the specified interval is less than one second (<code>PT1S</code>). If the next scheduled call is due, and if a query with the same id is still running, it will be skipped.
<pre class="brush:xquery">
jobs:eval("prof:sleep(1500)", (), map { 'interval': 'PT1S', 'end': 'PT10S' })
</pre>
* The following expression, if stored as a file, calls and evaluates itself every 5 seconds:
<pre class="brush:xquery">
jobs:eval(
file:read-text(static-base-uri()),
map { },
map { 'start': 'PT5S' }
)
</pre>
|}
==jobs:invoke==
{{Mark|Introduced with Version 8.7}}
{| width='100%'
|-
| width='120' | '''Signatures'''
|{{Func|jobs:invoke|$uri as xs:string|xs:string}}<br />{{Func|jobs:invoke|$uri as xs:string, $bindings as map(*)?|xs:string}}<br />{{Func|jobs:invoke|$uri as xs:string, $bindings as map(*)?, $options as map(xs:string, xs:string)|xs:string}}<br />
|-
| '''Summary'''
|Schedules the evaluation of the XQuery expression located at {{Code|$uri}} and returns a query id. The semantics and remaining arguments are identical to [[#jobs:eval|jobs:eval]].
|-
| '''Errors'''
|{{Error|overflow|#Errors}} Query execution is rejected, because too many jobs are queued or being executed. {{Option|CACHETIMEOUT}} can be decreased if the default setting is too restrictive.<br/>{{Error|range|#Errors}} A specified time or duration is out of range.<br/>{{Error|id|#Errors}} The specified id is invalid or has already been assigned.
|-
| '''Examples'''
|
* Runs an XQuery expression that may perform some cleanups:
<pre class='brush:xquery'>
jobs:invoke("cleanup.xq", (), ())
</pre>
|}
};
</pre>
* The following query demonstrates how the results of an asynchronously executed query can be returned within the same query. Please remember that this is not the common way how these functions will be used in practice:
<pre class='brush:xquery'>
let $query := jobs:eval('(1 to 10000000)[. = 1]', map{}, map{ 'cache': true() })
return (
jobs:result($query)
)
</pre>
Please note that queries of this kind can cause deadlocks. For example, if both the original query and the query to be executed asynchronously perform updates on the same database, the second query would only be run after the first one has been executed, and the first query will wait forever. This is why you should avoid this pattern in practice and resort to [[XQuery Module#xquery:fork-join|xquery:fork-join]] if you want to do things in parallel.
|}
|{{Code|id}}
| The specified is invalid or has already been assigned.
|-
|{{Code|self}}
| The current job cannot be addressed.
|}
=Changelog=
;Version 8.7
* Added: [[#jobs:invoke|jobs:invoke]]
;Version 8.6
