Class: Delayed::Backend::ActiveRecord::Job

Inherits:
ActiveRecord::Base
  • Object
show all
Includes:
Base
Defined in:
lib/delayed/backend/active_record.rb

Overview

A job object that is persisted to the database. Contains the work object as a YAML field.

Constant Summary

Constants included from Base

Base::ParseObjectFromYaml

Class Method Summary collapse

Instance Method Summary collapse

Methods included from Base

#failed?, included, #invoke_job, #max_attempts, #name, #payload_object, #payload_object=, #reschedule_at, #unlock

Class Method Details

.after_fork ⇒ Object

[View source]

33
34
35
 
# File 'lib/delayed/backend/active_record.rb', line 33

def self.after_fork
  ::ActiveRecord::Base.connection.reconnect!
end

.clear_locks!(worker_name) ⇒ Object

When a worker is exiting, make sure we don’t have any locked jobs.

[View source]

38
39
40
 
# File 'lib/delayed/backend/active_record.rb', line 38

def self.clear_locks!(worker_name)
  update_all("locked_by = null, locked_at = null", ["locked_by = ?", worker_name])
end

.db_time_now ⇒ Object

Get the current time (GMT or local depending on DB) Note: This does not ping the DB to get the time, so all your clients must have syncronized clocks.

[View source]

80
81
82
83
84
85
86
87
88
 
# File 'lib/delayed/backend/active_record.rb', line 80

def self.db_time_now
  if Time.zone
    Time.zone.now
  elsif ::ActiveRecord::Base.default_timezone == :utc
    Time.now.utc
  else
    Time.now
  end
end

.find_available(worker_name, limit = 5, max_run_time = Worker.max_run_time) ⇒ Object

Find a few candidate jobs to run (in case some immediately get locked by others).

[View source]

43
44
45
46
47
48
49
50
51
52
 
# File 'lib/delayed/backend/active_record.rb', line 43

def self.find_available(worker_name, limit = 5, max_run_time = Worker.max_run_time)
  scope = self.ready_to_run(worker_name, max_run_time)
  scope = scope.scoped(:conditions => ['priority >= ?', Worker.min_priority]) if Worker.min_priority
  scope = scope.scoped(:conditions => ['priority <= ?', Worker.max_priority]) if Worker.max_priority
  scope = scope.scoped(:conditions => ["queue IN (?)", Worker.queues]) if Worker.queues.any?

  ::ActiveRecord::Base.silence do
    scope.by_priority.all(:limit => limit)
  end
end

Instance Method Details

#lock_exclusively!(max_run_time, worker) ⇒ Object

Lock this job for this worker. Returns true if we have the lock, false otherwise.

[View source]

56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
 
# File 'lib/delayed/backend/active_record.rb', line 56

def lock_exclusively!(max_run_time, worker)
  now = self.class.db_time_now
  affected_rows = if locked_by != worker
    # We don't own this job so we will update the locked_by name and the locked_at
    self.class.update_all(["locked_at = ?, locked_by = ?", now, worker], ["id = ? and (locked_at is null or locked_at < ?) and (run_at <= ?)", id, (now - max_run_time.to_i), now])
  else
    # We already own this job, this may happen if the job queue crashes.
    # Simply resume and update the locked_at
    self.class.update_all(["locked_at = ?", now], ["id = ? and locked_by = ?", id, worker])
  end
  if affected_rows == 1
    self.locked_at = now
    self.locked_by = worker
    self.locked_at_will_change!
    self.locked_by_will_change!
    return true
  else
    return false
  end
end