Class: ActiveSupport::Notifications::Instrumenter

Inherits:
Object
  • Object
show all
Defined in:
activesupport/lib/active_support/notifications/instrumenter.rb

Overview

Instrumenters are stored in a thread local.

Defined Under Namespace

Classes: LegacyHandle

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(notifier) ⇒ Instrumenter

Returns a new instance of Instrumenter.



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# File 'activesupport/lib/active_support/notifications/instrumenter.rb', line 12

def initialize(notifier)
  unless notifier.respond_to?(:build_handle)
    notifier = LegacyHandle::Wrapper.new(notifier)
  end

  @id       = unique_id
  @notifier = notifier
end

Instance Attribute Details

#idObject (readonly)

Returns the value of attribute id



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# File 'activesupport/lib/active_support/notifications/instrumenter.rb', line 10

def id
  @id
end

Instance Method Details

#build_handle(name, payload) ⇒ Object

Returns a “handle” for an event with the given name and payload

#start and #finish must each be called exactly once on the returned object.

Where possible, it’s best to use #instrument, which will record the start and finish of the event and correctly handle any exceptions. build_handle is a low-level API intended for cases where using #instrument isn’t possible.

See ActiveSupport::Notifications::Fanout::Handle



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# File 'activesupport/lib/active_support/notifications/instrumenter.rb', line 78

def build_handle(name, payload)
  @notifier.build_handle(name, @id, payload)
end

#finish(name, payload) ⇒ Object

Send a finish notification with name and payload.



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# File 'activesupport/lib/active_support/notifications/instrumenter.rb', line 92

def finish(name, payload)
  @notifier.finish name, @id, payload
end

#finish_with_state(listeners_state, name, payload) ⇒ Object



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# File 'activesupport/lib/active_support/notifications/instrumenter.rb', line 96

def finish_with_state(listeners_state, name, payload)
  @notifier.finish name, @id, payload, listeners_state
end

#instrument(name, payload = {}) ⇒ Object

Given a block, instrument it by measuring the time taken to execute and publish it. Without a block, simply send a message via the notifier. Notice that events get sent even if an error occurs in the passed-in block.



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# File 'activesupport/lib/active_support/notifications/instrumenter.rb', line 54

def instrument(name, payload = {})
  handle = build_handle(name, payload)
  handle.start
  begin
    yield payload if block_given?
  rescue Exception => e
    payload[:exception] = [e.class.name, e.message]
    payload[:exception_object] = e
    raise e
  ensure
    handle.finish
  end
end

#new_event(name, payload = {}) ⇒ Object

:nodoc:



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# File 'activesupport/lib/active_support/notifications/instrumenter.rb', line 82

def new_event(name, payload = {}) # :nodoc:
  Event.new(name, nil, nil, @id, payload)
end

#start(name, payload) ⇒ Object

Send a start notification with name and payload.



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# File 'activesupport/lib/active_support/notifications/instrumenter.rb', line 87

def start(name, payload)
  @notifier.start name, @id, payload
end