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NAME

Resque::Worker - Does the hard work of babysitting Resque::Job's

VERSION

version 0.20

ATTRIBUTES

resque

The Resque object running this worker.

queues

Queues this worker should fetch jobs from.

stat

See Resque::Stat.

id

Unique identifier for the running worker. Used to set process status all around.

The worker stringify to this attribute.

verbose

Set to a true value to make this worker report what's doing while on work().

cant_fork

Set it to a true value to stop this worker from fork jobs.

By default, the worker will fork the job out and control the children process. This make the worker more resilient to memory leaks.

child

PID of current running child.

shutdown

When true, this worker will shutdown after finishing current job.

paused

When true, this worker won't proccess more jobs till false.

interval

Float representing the polling frequency. The default is 5 seconds, but for a semi-active app you may want to use a smaller value.

METHODS

pause

Stop processing jobs after the current one has completed (if we're currently running one).

unpause

Start processing jobs again after a pause

shutdown_please

Schedule this worker for shutdown. Will finish processing the current job.

shutdown_now

Kill the child and shutdown immediately.

work

Calling this method will make this worker to start pulling & running jobs from queues().

This is the main wheel and will run while shutdown() is false.

work_tick

Perform() one job and wait till it finish.

perform

Call perform() on the given Resque::Job capturing and reporting any exception.

kill_child

Kills the forked child immediately, without remorse. The job it is processing will not be completed.

add_queue

Add a queue this worker should listen to.

del_queue

Stop listening to the given queue.

reserve

Pull the next job to be precessed.

working_on

Set worker and working status on the given Resque::Job.

done_working

Inform the backend this worker has done its current job

started

What time did this worker start? Returns an instance of DateTime.

TODO: not working in this release. This is returning a string used internally.

set_started

Tell Redis we've started

processing

Returns a hash explaining the Job we're currently processing, if any.

state

Returns a string representing the current worker state, which can be either working or idle

is_working

Boolean - true if working, false if not

is_idle

Boolean - true if idle, false if not

procline

Given a string, sets the procline ($0) and logs. Procline is always in the format of: resque-VERSION: STRING

startup

Helper method called by work() to:

  1. register_signal_handlers()
  2. prune_dead_workers();
  3. register_worker();

register_signal_handlers

Registers the various signal handlers a worker responds to.

 TERM: Shutdown immediately, stop processing jobs.
  INT: Shutdown immediately, stop processing jobs.
 QUIT: Shutdown after the current job has finished processing.
 USR1: Kill the forked child immediately, continue processing jobs.
 USR2: Don't process any new jobs
 CONT: Start processing jobs again after a USR2

prune_dead_workers

Looks for any workers which should be running on this server and, if they're not, removes them from Redis.

This is a form of garbage collection. If a server is killed by a hard shutdown, power failure, or something else beyond our control, the Resque workers will not die gracefully and therefore will leave stale state information in Redis.

By checking the current Redis state against the actual environment, we can determine if Redis is old and clean it up a bit.

register_worker

Registers ourself as a worker. Useful when entering the worker lifecycle on startup.

unregister_worker

Unregisters ourself as a worker. Useful when shutting down.

worker_pids

Returns an Array of string pids of all the other workers on this machine. Useful when pruning dead workers on startup.

log

If verbose() is true, this will print to STDERR.

processed

Retrieve from Resque::Stat many jobs has done this worker. Pass a true argument to increment by one.

failed

How many failed jobs has this worker seen. Pass a true argument to increment by one.

find

Returns a single worker object. Accepts a string id.

all

Returns all worker registered on the backend.

exists

Returns true if the given worker id exists on redis() backend.

AUTHOR

Diego Kuperman <diego@freekeylabs.com>

COPYRIGHT AND LICENSE

This software is copyright (c) 2015 by Diego Kuperman.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.