class ActiveSupport::Notifications::Instrumenter

Instrumenters are stored in a thread local.

Attributes

id[R]

Public Class Methods

new(notifier) click to toggle source
# File 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

Public Instance Methods

build_handle(name, payload) click to toggle source

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

# File lib/active_support/notifications/instrumenter.rb, line 78
def build_handle(name, payload)
  @notifier.build_handle(name, @id, payload)
end
finish(name, payload) click to toggle source

Send a finish notification with name and payload.

# File 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) click to toggle source
# File 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 = {}) { |payload| ... } click to toggle source

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.

# File 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
start(name, payload) click to toggle source

Send a start notification with name and payload.

# File lib/active_support/notifications/instrumenter.rb, line 87
def start(name, payload)
  @notifier.start name, @id, payload
end

Private Instance Methods

unique_id() click to toggle source
# File lib/active_support/notifications/instrumenter.rb, line 101
def unique_id
  SecureRandom.hex(10)
end