diff options
Diffstat (limited to 'activesupport/lib/active_support/notifications.rb')
| -rw-r--r-- | activesupport/lib/active_support/notifications.rb | 36 |
1 files changed, 32 insertions, 4 deletions
diff --git a/activesupport/lib/active_support/notifications.rb b/activesupport/lib/active_support/notifications.rb index 6207de8094..7ccc333463 100644 --- a/activesupport/lib/active_support/notifications.rb +++ b/activesupport/lib/active_support/notifications.rb @@ -34,7 +34,7 @@ module ActiveSupport # name # => String, name of the event (such as 'render' from above) # start # => Time, when the instrumented block started execution # finish # => Time, when the instrumented block ended execution - # id # => String, unique ID for this notification + # id # => String, unique ID for the instrumenter that fired the event # payload # => Hash, the payload # end # @@ -59,7 +59,7 @@ module ActiveSupport # event.payload # => { extra: :information } # # The block in the <tt>subscribe</tt> call gets the name of the event, start - # timestamp, end timestamp, a string with a unique identifier for that event + # timestamp, end timestamp, a string with a unique identifier for that event's instrumenter # (something like "535801666f04d0298cd6"), and a hash with the payload, in # that order. # @@ -67,9 +67,12 @@ module ActiveSupport # have a key <tt>:exception</tt> with an array of two elements as value: a string with # the name of the exception class, and the exception message. # The <tt>:exception_object</tt> key of the payload will have the exception - # itself as the value. + # itself as the value: # - # As the previous example depicts, the class <tt>ActiveSupport::Notifications::Event</tt> + # event.payload[:exception] # => ["ArgumentError", "Invalid value"] + # event.payload[:exception_object] # => #<ArgumentError: Invalid value> + # + # As the earlier example depicts, the class <tt>ActiveSupport::Notifications::Event</tt> # is able to take the arguments as they come and provide an object-oriented # interface to that data. # @@ -171,6 +174,31 @@ module ActiveSupport end end + # Subscribe to a given event name with the passed +block+. + # + # You can subscribe to events by passing a String to match exact event + # names, or by passing a Regexp to match all events that match a pattern. + # + # ActiveSupport::Notifications.subscribe(/render/) do |*args| + # @event = ActiveSupport::Notifications::Event.new(*args) + # end + # + # The +block+ will receive five parameters with information about the event: + # + # ActiveSupport::Notifications.subscribe('render') do |name, start, finish, id, payload| + # name # => String, name of the event (such as 'render' from above) + # start # => Time, when the instrumented block started execution + # finish # => Time, when the instrumented block ended execution + # id # => String, unique ID for the instrumenter that fired the event + # payload # => Hash, the payload + # end + # + # If the block passed to the method only takes one parameter, + # it will yield an event object to the block: + # + # ActiveSupport::Notifications.subscribe(/render/) do |event| + # @event = event + # end def subscribe(*args, &block) notifier.subscribe(*args, &block) end |