diff options
Diffstat (limited to 'activesupport/lib/active_support/log_subscriber.rb')
| -rw-r--r-- | activesupport/lib/active_support/log_subscriber.rb | 39 |
1 files changed, 31 insertions, 8 deletions
diff --git a/activesupport/lib/active_support/log_subscriber.rb b/activesupport/lib/active_support/log_subscriber.rb index 0f7be06c8e..938cfdb914 100644 --- a/activesupport/lib/active_support/log_subscriber.rb +++ b/activesupport/lib/active_support/log_subscriber.rb @@ -5,8 +5,8 @@ require "active_support/core_ext/class/attribute" require "active_support/subscriber" module ActiveSupport - # ActiveSupport::LogSubscriber is an object set to consume - # ActiveSupport::Notifications with the sole purpose of logging them. + # <tt>ActiveSupport::LogSubscriber</tt> is an object set to consume + # <tt>ActiveSupport::Notifications</tt> with the sole purpose of logging them. # The log subscriber dispatches notifications to a registered object based # on its given namespace. # @@ -16,7 +16,7 @@ module ActiveSupport # module ActiveRecord # class LogSubscriber < ActiveSupport::LogSubscriber # def sql(event) - # "#{event.payload[:name]} (#{event.duration}) #{event.payload[:sql]}" + # info "#{event.payload[:name]} (#{event.duration}) #{event.payload[:sql]}" # end # end # end @@ -29,13 +29,36 @@ module ActiveSupport # subscriber, the line above should be called after your # <tt>ActiveRecord::LogSubscriber</tt> definition. # - # After configured, whenever a "sql.active_record" notification is published, - # it will properly dispatch the event (ActiveSupport::Notifications::Event) to - # the sql method. + # After configured, whenever a <tt>"sql.active_record"</tt> notification is published, + # it will properly dispatch the event + # (<tt>ActiveSupport::Notifications::Event</tt>) to the sql method. + # + # Being an <tt>ActiveSupport::Notifications</tt> consumer, + # <tt>ActiveSupport::LogSubscriber</tt> exposes a simple interface to check if + # instrumented code raises an exception. It is common to log a different + # message in case of an error, and this can be achieved by extending + # the previous example: + # + # module ActiveRecord + # class LogSubscriber < ActiveSupport::LogSubscriber + # def sql(event) + # exception = event.payload[:exception] + # + # if exception + # exception_object = event.payload[:exception_object] + # + # error "[ERROR] #{event.payload[:name]}: #{exception.join(', ')} " \ + # "(#{exception_object.backtrace.first})" + # else + # # standard logger code + # end + # end + # end + # end # # Log subscriber also has some helpers to deal with logging and automatically - # flushes all logs when the request finishes (via action_dispatch.callback - # notification) in a Rails environment. + # flushes all logs when the request finishes + # (via <tt>action_dispatch.callback</tt> notification) in a Rails environment. class LogSubscriber < Subscriber # Embed in a String to clear all previous ANSI sequences. CLEAR = "\e[0m" |