1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
|
# frozen_string_literal: true
require "active_support/core_ext/numeric/time"
module ActiveJob
# Provides behavior for retrying and discarding jobs on exceptions.
module Exceptions
extend ActiveSupport::Concern
module ClassMethods
# Catch the exception and reschedule job for re-execution after so many seconds, for a specific number of attempts.
# The number of attempts includes the total executions of a job, not just the retried executions.
# If the exception keeps getting raised beyond the specified number of attempts, the exception is allowed to
# bubble up to the underlying queuing system, which may have its own retry mechanism or place it in a
# holding queue for inspection.
#
# You can also pass a block that'll be invoked if the retry attempts fail for custom logic rather than letting
# the exception bubble up. This block is yielded with the job instance as the first and the error instance as the second parameter.
#
# ==== Options
# * <tt>:wait</tt> - Re-enqueues the job with a delay specified either in seconds (default: 3 seconds),
# as a computing proc that the number of executions so far as an argument, or as a symbol reference of
# <tt>:exponentially_longer</tt>, which applies the wait algorithm of <tt>(executions ** 4) + 2</tt>
# (first wait 3s, then 18s, then 83s, etc)
# * <tt>:attempts</tt> - Re-enqueues the job the specified number of times (default: 5 attempts),
# attempts here refers to the total number of times the job is executed, not just retried executions
# * <tt>:queue</tt> - Re-enqueues the job on a different queue
# * <tt>:priority</tt> - Re-enqueues the job with a different priority
#
# ==== Examples
#
# class RemoteServiceJob < ActiveJob::Base
# retry_on CustomAppException # defaults to 3s wait, 5 attempts
# retry_on AnotherCustomAppException, wait: ->(executions) { executions * 2 }
# retry_on(YetAnotherCustomAppException) do |job, error|
# ExceptionNotifier.caught(error)
# end
# retry_on ActiveRecord::Deadlocked, wait: 5.seconds, attempts: 3
# retry_on Net::OpenTimeout, wait: :exponentially_longer, attempts: 10
#
# def perform(*args)
# # Might raise CustomAppException, AnotherCustomAppException, or YetAnotherCustomAppException for something domain specific
# # Might raise ActiveRecord::Deadlocked when a local db deadlock is detected
# # Might raise Net::OpenTimeout when the remote service is down
# end
# end
def retry_on(*exceptions, wait: 3.seconds, attempts: 5, queue: nil, priority: nil)
rescue_from(*exceptions) do |error|
if executions < attempts
retry_job wait: determine_delay(wait), queue: queue, priority: priority, error: error
else
if block_given?
instrument :retry_stopped, error: error do
yield self, error
end
else
instrument :retry_stopped, error: error
raise error
end
end
end
end
# Discard the job with no attempts to retry, if the exception is raised. This is useful when the subject of the job,
# like an Active Record, is no longer available, and the job is thus no longer relevant.
#
# You can also pass a block that'll be invoked. This block is yielded with the job instance as the first and the error instance as the second parameter.
#
# ==== Example
#
# class SearchIndexingJob < ActiveJob::Base
# discard_on ActiveJob::DeserializationError
# discard_on(CustomAppException) do |job, error|
# ExceptionNotifier.caught(error)
# end
#
# def perform(record)
# # Will raise ActiveJob::DeserializationError if the record can't be deserialized
# # Might raise CustomAppException for something domain specific
# end
# end
def discard_on(*exceptions)
rescue_from(*exceptions) do |error|
instrument :discard, error: error do
yield self, error if block_given?
end
end
end
end
# Reschedules the job to be re-executed. This is useful in combination
# with the +rescue_from+ option. When you rescue an exception from your job
# you can ask Active Job to retry performing your job.
#
# ==== Options
# * <tt>:wait</tt> - Enqueues the job with the specified delay in seconds
# * <tt>:wait_until</tt> - Enqueues the job at the time specified
# * <tt>:queue</tt> - Enqueues the job on the specified queue
# * <tt>:priority</tt> - Enqueues the job with the specified priority
#
# ==== Examples
#
# class SiteScraperJob < ActiveJob::Base
# rescue_from(ErrorLoadingSite) do
# retry_job queue: :low_priority
# end
#
# def perform(*args)
# # raise ErrorLoadingSite if cannot scrape
# end
# end
def retry_job(options = {})
instrument :enqueue_retry, options.slice(:error, :wait) do
enqueue options
end
end
private
def determine_delay(seconds_or_duration_or_algorithm)
case seconds_or_duration_or_algorithm
when :exponentially_longer
(executions**4) + 2
when ActiveSupport::Duration
duration = seconds_or_duration_or_algorithm
duration.to_i
when Integer
seconds = seconds_or_duration_or_algorithm
seconds
when Proc
algorithm = seconds_or_duration_or_algorithm
algorithm.call(executions)
else
raise "Couldn't determine a delay based on #{seconds_or_duration_or_algorithm.inspect}"
end
end
def instrument(name, error: nil, wait: nil, &block)
payload = { job: self, adapter: self.class.queue_adapter, error: error, wait: wait }
ActiveSupport::Notifications.instrument("#{name}.active_job", payload, &block)
end
end
end
|
