JobQueue
JobQueue
A JobQueue is used to process Jobs. A job is added to the queue via the
.add() method, and the configured JobQueueStrategy will check for new jobs and process each
according to the defined process function.
Note: JobQueue instances should not be directly instantiated. Rather, the
JobQueueService createQueue() method should be used (see that service
for example usage).
Signature
class JobQueue<Data extends JobData<Data> = {}> {
name: string
started: boolean
constructor(options: CreateQueueOptions<Data>, jobQueueStrategy: JobQueueStrategy, jobBufferService: JobBufferService)
async add(data: Data, options?: Pick<JobConfig<Data>, 'retries'>) => Promise<SubscribableJob<Data>>;
}
Members
name
property
type:
string
started
property
type:
boolean
constructor
method
type:
(options: CreateQueueOptions<Data>, jobQueueStrategy: JobQueueStrategy, jobBufferService: JobBufferService) => JobQueue
add
async method
type:
(data: Data, options?: Pick<JobConfig<Data>, 'retries'>) => Promise<SubscribableJob<Data>>
Adds a new Job to the queue. The resolved SubscribableJob allows the calling code to subscribe to updates to the Job:
Example
const job = await this.myQueue.add({ intervalMs, shouldFail }, { retries: 2 });
return job.updates().pipe(
map(update => {
// The returned Observable will emit a value for every update to the job
// such as when the `progress` or `status` value changes.
Logger.info(`Job ${update.id}: progress: ${update.progress}`);
if (update.state === JobState.COMPLETED) {
Logger.info(`COMPLETED ${update.id}: ${update.result}`);
}
return update.result;
}),
catchError(err => of(err.message)),
);
Alternatively, if you aren’t interested in the intermediate
progress changes, you can convert to a Promise like this:
Example
const job = await this.myQueue.add({ intervalMs, shouldFail }, { retries: 2 });
return job.updates().toPromise()
.then(update => update.result),
.catch(err => err.message);