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
|
require 'active_support/core_ext/module/delegation'
module ActiveSupport
# Notifications provides an instrumentation API for Ruby. To instrument an
# action in Ruby you just need to do:
#
# ActiveSupport::Notifications.instrument(:render, :extra => :information) do
# render :text => "Foo"
# end
#
# You can consume those events and the information they provide by registering
# a log subscriber. For instance, let's store all instrumented events in an array:
#
# @events = []
#
# ActiveSupport::Notifications.subscribe do |*args|
# @events << ActiveSupport::Notifications::Event.new(*args)
# end
#
# ActiveSupport::Notifications.instrument(:render, :extra => :information) do
# render :text => "Foo"
# end
#
# event = @events.first
# event.name #=> :render
# event.duration #=> 10 (in milliseconds)
# event.payload #=> { :extra => :information }
#
# When subscribing to Notifications, you can pass a pattern, to only consume
# events that match the pattern:
#
# ActiveSupport::Notifications.subscribe(/render/) do |event|
# @render_events << event
# end
#
# Notifications ships with a queue implementation that consumes and publish events
# to log subscribers in a thread. You can use any queue implementation you want.
#
module Notifications
autoload :Instrumenter, 'active_support/notifications/instrumenter'
autoload :Event, 'active_support/notifications/instrumenter'
autoload :Fanout, 'active_support/notifications/fanout'
@instrumenters = Hash.new { |h,k| h[k] = notifier.listening?(k) }
class << self
attr_writer :notifier
delegate :publish, :to => :notifier
def instrument(name, payload = {})
if @instrumenters[name]
instrumenter.instrument(name, payload) { yield payload if block_given? }
else
yield payload if block_given?
end
end
def subscribe(*args, &block)
notifier.subscribe(*args, &block).tap do
@instrumenters.clear
end
end
def unsubscribe(*args)
notifier.unsubscribe(*args)
@instrumenters.clear
end
def notifier
@notifier ||= Fanout.new
end
def instrumenter
Thread.current[:"instrumentation_#{notifier.object_id}"] ||= Instrumenter.new(notifier)
end
end
end
end
|
