exception_notification-rake - ExceptionNotifier for Rake tasks
This Ruby gem is an extension of the exception_notification gem to support sending mail upon failures in Rake tasks. This is useful if you run Rake tasks as batch jobs on a schedule, particularly if you're using the Heroku Scheduler add-on.
Usage
Basic Configuration
Exception notification must be set up in your Rails config files. In general, you'll want to do this in environment-specific config files, such as config/environments/production.rb. Minimal configuration:
# config/environments/production.rb
YourApp::Application.configure do
# Other configuration here, including ActionMailer config ...
config.middleware.use ExceptionNotifier,
:sender_address => %{"notifier" <[email protected]>},
:exception_recipients => %w{[email protected]},
:ignore_if => lambda { true }
ExceptionNotifier::Rake.configure
end
Note: This uses :ignore_if to suppress all exception notifications triggered by the Rails server itself (as opposed to Rake). If you want those notifications as well, omit the :ignore_if option.
If you are already using ExceptionNotifier anyway, you don't need to configure it again and all you need is:
# config/environments/production.rb
YourApp::Application.configure do
# Other configuration here, including ExceptionNotifer and ActionMailer config ...
ExceptionNotifier::Rake.configure
end
Note: As a prerequisite for sending mail your Rails Action Mailer needs to be configured in the environment where you're using exception notification. See the Rails guide on Action Mailer.
Notification Example
Email sent upon a failure will include the Rake tasks executed and a stacktrace. This is the result from calling an undefined method khaaaaan! in a task called failing_task:
Subject: [Rake Failure] (NoMethodError) "undefined method `khaaaaan!' for main:Object"
From: "notifier" <[email protected]>
To: <[email protected]>
A NoMethodError occurred in background at 2013-02-07 18:31:57 UTC :
undefined method `khaaaaan!' for main:Object
lib/tasks/scheduler.rake:33:in `block in <top (required)>'
-------------------------------
Rake:
-------------------------------
rake failing_task
-------------------------------
Backtrace:
-------------------------------
lib/tasks/scheduler.rake:33:in `block in <top (required)>'
.rvm/gems/ruby-1.9.3-p327/gems/rake-10.0.3/lib/rake/task.rb:228:in `call'
.rvm/gems/ruby-1.9.3-p327/gems/rake-10.0.3/lib/rake/task.rb:228:in `block in execute'
.rvm/gems/ruby-1.9.3-p327/gems/rake-10.0.3/lib/rake/task.rb:223:in `each'
.rvm/gems/ruby-1.9.3-p327/gems/rake-10.0.3/lib/rake/task.rb:223:in `execute'
.rvm/gems/ruby-1.9.3-p327/gems/rake-10.0.3/lib/rake/task.rb:166:in `block in invoke_with_call_chain'
.rvm/rubies/ruby-1.9.3-p327/lib/ruby/1.9.1/monitor.rb:211:in `mon_synchronize'
.rvm/gems/ruby-1.9.3-p327/gems/rake-10.0.3/lib/rake/task.rb:159:in `invoke_with_call_chain'
.rvm/gems/ruby-1.9.3-p327/gems/rake-10.0.3/lib/rake/task.rb:152:in `invoke'
.rvm/gems/ruby-1.9.3-p327/gems/rake-10.0.3/lib/rake/application.rb:143:in `invoke_task'
.rvm/gems/ruby-1.9.3-p327/gems/rake-10.0.3/lib/rake/application.rb:101:in `block (2 levels) in top_level'
.rvm/gems/ruby-1.9.3-p327/gems/rake-10.0.3/lib/rake/application.rb:101:in `each'
.rvm/gems/ruby-1.9.3-p327/gems/rake-10.0.3/lib/rake/application.rb:101:in `block in top_level'
.rvm/gems/ruby-1.9.3-p327/gems/rake-10.0.3/lib/rake/application.rb:110:in `run_with_threads'
.rvm/gems/ruby-1.9.3-p327/gems/rake-10.0.3/lib/rake/application.rb:95:in `top_level'
.rvm/gems/ruby-1.9.3-p327/gems/rake-10.0.3/lib/rake/application.rb:73:in `block in run'
.rvm/gems/ruby-1.9.3-p327/gems/rake-10.0.3/lib/rake/application.rb:160:in `standard_exception_handling'
.rvm/gems/ruby-1.9.3-p327/gems/rake-10.0.3/lib/rake/application.rb:70:in `run'
.rvm/gems/ruby-1.9.3-p327/gems/rake-10.0.3/bin/rake:33:in `<top (required)>'
.rvm/gems/ruby-1.9.3-p327/bin/rake:23:in `load'
.rvm/gems/ruby-1.9.3-p327/bin/rake:23:in `<main>'
(If you're spotting encoding issues here, those appear to be a problem upstream in the exception_notification gem.)
Usage with Heroku Scheduler
If you're using Heroku, the Scheduler add-on is a very convenient and cheap (i.e., free) way to run scheduled batch jobs. In a Rails environment it's easiest to define batch jobs as Rake tasks. However, the only way to find out whether a task run by the scheduler succeeded or failed is generally reading the logs.
This gem fixes this issue. If you configure exception notification as described above it should work out of the box with the Heroku Scheduler. (Provided you have email delivery set up in your Heroku app - you could try the SendGrid add-on which comes in a free version that should be good enough for notifications.)
Customization
You can pass configuration options to ExceptionNotifier::Rake.configure. It accepts all the same options as standard ExceptionNotifier (see its documentation). These options will be applied only to notifications sent as a result of Rake failures.
The most likely options you'll want to use are :email_prefix and :exception_recpients. Example:
ExceptionNotifier::Rake.configure(
:email_prefix => "[Cron Failure] ",
:exception_recipients => %w{[email protected] [email protected]})
This will prefix the email subjects of Rake failure notifications with [Cron Failure] and will send them to the two given email addresses. Note that if you set the same options when you configure ExceptionNotifier itself, they will be overridden but for Rake failures only.
If you want to configure sections, which is unlikely, note that by default the sections ['rake', 'backtrace'] are used (where rake is a custom section introduced by this gem).
Installation
gem install exception_notification-rake
License
Distributed under an MIT license.