Class: Resque::Job

Inherits:
Object
  • Object
show all
Extended by:
Helpers
Includes:
Helpers
Defined in:
lib/resque/job.rb

Overview

A Resque::Job represents a unit of work. Each job lives on a single queue and has an associated payload object. The payload is a hash with two attributes: class and args. The class is the name of the Ruby class which should be used to run the job. The args are an array of arguments which should be passed to the Ruby class's perform class-level method.

You can manually run a job using this code:

job = Resque::Job.reserve(:high)
klass = Resque::Job.constantize(job.payload['class'])
klass.perform(*job.payload['args'])

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Methods included from Helpers

classify, constantize, decode, encode, redis

Constructor Details

#initialize(queue, payload) ⇒ Job

Returns a new instance of Job.



28
29
30
31
 
# File 'lib/resque/job.rb', line 28

def initialize(queue, payload)
  @queue = queue
  @payload = payload
end

Instance Attribute Details

#payload ⇒ Object (readonly)

This job's associated payload object.



26
27
28
 
# File 'lib/resque/job.rb', line 26

def payload
  @payload
end

#queue ⇒ Object (readonly)

The name of the queue from which this job was pulled (or is to be placed)



23
24
25
 
# File 'lib/resque/job.rb', line 23

def queue
  @queue
end

#worker ⇒ Object

The worker object which is currently processing this job.



19
20
21
 
# File 'lib/resque/job.rb', line 19

def worker
  @worker
end

Class Method Details

.create(queue, klass, *args) ⇒ Object

Creates a job by placing it on a queue. Expects a string queue name, a string class name, and an optional array of arguments to pass to the class' perform method.

Raises an exception if no queue or class is given.



38
39
40
41
42
43
44
45
46
47
48
 
# File 'lib/resque/job.rb', line 38

def self.create(queue, klass, *args)
  if queue.to_s.empty?
    raise NoQueueError.new("Jobs must be placed onto a queue.")
  end

  if klass.to_s.empty?
    raise NoClassError.new("Jobs must be given a class.")
  end

  Resque.push(queue, :class => klass.to_s, :args => args)
end

.reserve(queue) ⇒ Object

Given a string queue name, returns an instance of Resque::Job if any jobs are available. If not, returns nil.



52
53
54
55
 
# File 'lib/resque/job.rb', line 52

def self.reserve(queue)
  return unless payload = Resque.pop(queue)
  new(queue, payload)
end

Instance Method Details

#args ⇒ Object

Returns an array of args represented in this job's payload.



71
72
73
 
# File 'lib/resque/job.rb', line 71

def args
  @payload['args']
end

#fail(exception) ⇒ Object

Given an exception object, hands off the needed parameters to the Failure module.



77
78
79
80
81
82
83
 
# File 'lib/resque/job.rb', line 77

def fail(exception)
  Failure.create \
    :payload   => payload,
    :exception => exception,
    :worker    => worker,
    :queue     => queue
end

#inspect ⇒ Object

String representation



86
87
88
89
 
# File 'lib/resque/job.rb', line 86

def inspect
  obj = @payload
  "(Job{%s} | %s | %s)" % [ @queue, obj['class'], obj['args'].inspect ]
end

#payload_class ⇒ Object

Returns the actual class constant represented in this job's payload.



66
67
68
 
# File 'lib/resque/job.rb', line 66

def payload_class
  @payload_class ||= constantize(@payload['class'])
end

#perform ⇒ Object

Attempts to perform the work represented by this job instance. Calls #perform on the class given in the payload with the arguments given in the payload.



60
61
62
63
 
# File 'lib/resque/job.rb', line 60

def perform
  return unless payload_class && payload_class.respond_to?(:perform)
  args ? payload_class.perform(*args) : payload_class.perform
end