Class | Delayed::Backend::ActiveRecord::Job |
In: |
lib/delayed/backend/active_record.rb
|
Parent: | ::ActiveRecord::Base |
A job object that is persisted to the database. Contains the work object as a YAML field.
# File lib/delayed/backend/active_record.rb, line 33 33: def self.after_fork 34: ::ActiveRecord::Base.connection.reconnect! 35: end
When a worker is exiting, make sure we don‘t have any locked jobs.
# File lib/delayed/backend/active_record.rb, line 38 38: def self.clear_locks!(worker_name) 39: update_all("locked_by = null, locked_at = null", ["locked_by = ?", worker_name]) 40: end
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.
# File lib/delayed/backend/active_record.rb, line 79 79: def self.db_time_now 80: if Time.zone 81: Time.zone.now 82: elsif ::ActiveRecord::Base.default_timezone == :utc 83: Time.now.utc 84: else 85: Time.now 86: end 87: end
Find a few candidate jobs to run (in case some immediately get locked by others).
# File lib/delayed/backend/active_record.rb, line 43 43: def self.find_available(worker_name, limit = 5, max_run_time = Worker.max_run_time) 44: scope = self.ready_to_run(worker_name, max_run_time) 45: scope = scope.scoped(:conditions => ['priority >= ?', Worker.min_priority]) if Worker.min_priority 46: scope = scope.scoped(:conditions => ['priority <= ?', Worker.max_priority]) if Worker.max_priority 47: 48: ::ActiveRecord::Base.silence do 49: scope.by_priority.all(:limit => limit) 50: end 51: end
Lock this job for this worker. Returns true if we have the lock, false otherwise.
# File lib/delayed/backend/active_record.rb, line 55 55: def lock_exclusively!(max_run_time, worker) 56: now = self.class.db_time_now 57: affected_rows = if locked_by != worker 58: # We don't own this job so we will update the locked_by name and the locked_at 59: 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]) 60: else 61: # We already own this job, this may happen if the job queue crashes. 62: # Simply resume and update the locked_at 63: self.class.update_all(["locked_at = ?", now], ["id = ? and locked_by = ?", id, worker]) 64: end 65: if affected_rows == 1 66: self.locked_at = now 67: self.locked_by = worker 68: self.locked_at_will_change! 69: self.locked_by_will_change! 70: return true 71: else 72: return false 73: end 74: end