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Exception Notifier

The Exception Notifier plugin provides a mailer object and a default set of templates for sending email notifications when errors occur in a Rails application. The plugin is configurable, allowing programmers to specify:

  • the sender address of the email
  • the recipient addresses
  • the text used to prefix the subject line

The email includes information about the current request, session, and environment, and also gives a backtrace of the exception.


Repository git://
License Rails' (MIT)
Rating (128 votes)
Created 18 May 2006


  • Avatar
    Andrew Selder
    18 January 2007

    This seems to break on Rails 1.2:

    I keep getting the following error message: Expected /Users/aselder/BostonLogic/match/config/../vendor/plugins/exceptionnotification/lib/exceptionnotifier.rb to define ExceptionNotifier

  • Rene Perrier
    21 February 2007

    Same problem with Rails 1.2 this article ( talks about it, but does not really offer a solution

  • Avatar
    15 April 2007

    You can get an updated version of this that should work with Rails 1.2 from the sample app.

  • Avatar
    6 May 2007

    Thanks for a highly useful plugin.

    I'm using Rails 1.2.3 and the plugin works just fine.

  • Avatar
    Brandon Keene
    9 May 2007

    Note, this plugin hooks into ActionController::rescueactionin_public()

    If you're working in your development environment or on your local machine, this won't be called and the plugin won't send e-mail.

    If you want to just try this out, throw this line at the bottom of app/controllers/application.rb:

    alias :rescueactionlocally :rescueactionin_public

    Assume you can send mail and you configured the plugin, voila! It works in development.

  • Avatar
    Brett Neumeier
    12 October 2007

    In ruby 1.8.6p111, rendering the _environment.rhtml plugin fails with "TemplateError: flag after width". This is fixed if you change the string "%-s" to "%-s" on line three of the template.

  • Chris
    18 October 2007

    This is the correct string: "%-*s:"

  • Jean-Michel
    3 December 2007

    To test under development mode, add alias :rescueactionlocally :rescueactionin_public in your ApplicationController (don't know why the underscore dissapear when copy-pasted!)

  • Avatar
    10 January 2008

    I was having trouble with it in a project, and found this:

    Then it began working for me!

  • Avatar
    William Evanson
    21 January 2008

    I keep getting a warning starting up my rails application warning: already initialized constant VIEW_PATH warning: already initialized constant APP_PATH warning: already initialized constant PARAMFILTERREPLACEMENT

    It started when I moved my app from 1.1.6 to 1.2.3.

  • Avatar
    25 January 2008


    For the life of me, I cannot get the Exception Notification plugin to send email when in development mode. When tracing with the debugger it seems that no exception handlers are regsitered [rescue.rb: if rescueactionwithhandler(exception)]. As a result, ExceptionNotifiable.rescueactioninpublic never executes.

    If you have any thoughts, I'd love to hear them.


    • I'm running Rails 2.0.2
    • I've restarted Webrick several times
    • for testing purposes, I'm forcing rails to throw a NameError exception
    • I know ActionMailer has been setup properly as I can send mail through it.

    [environment.rb] do |config| config.actioncontroller.considerallrequestslocal = false end

    ExceptionNotifier.exception_recipients = %w( ExceptionNotifier.sender_address = %w(


    class ApplicationController < ActionController::Base include ExceptionNotifiable local_addresses.clear end

  • Avatar
    3 July 2008

    I recently upgraded my app to rail 2.1 . I was running it in 1.2.3 all while.

    I hit this error: ActionView::TemplateFinder::InvalidViewPath (Unprocessed view path found: ... vendor/plugins/exception_notification/lib/../views"

    Has any faced this? How do I solve it?

    Thanks in Advance, Sandeep G

  • Avatar
    6 August 2008

    Sandeep: I'm having the exact same problem. Anyone have a solution?

  • Avatar
    19 August 2008

    This seems to get it going again in 2.1.

    In ExceptionNotifiable there is a templateroot method. Change "def templateroot" to "self.template_root =", and remove the "end".

    Sorry to be so elliptical, but this comment system obviously eats Ruby syntax for breakfast... :)

  • Avatar
    Stan Gudo
    20 August 2008

    I'm seeing the same problem as reported by Sandeep, can't seem to get it fixed. Any help appreciated. Thanks.

  • Avatar
    28 August 2008

    To fix this plugin for rails 2.1 go to class ExceptionNotifier, comment out the template root function and add templateroot= "#{File.dirname(FILE)}/../views" as the first line of the exceptionnotification function.

  • Avatar
    9 December 2008

    Must have plugin for applications that were recently deployed and could have some bugs ;)

  • Vijay
    21 January 2009

    Just installed the latest on GIT in Rails 2.2.2. This seems to break setting exceptionrecipients in production.rb, as it appears the vendor plugins get loaded after production.rb is processed and the require 'reinitializes' the ExceptionNotifier class a second time (resulting in the exceptionrecipients being reinitialized). A Workaround is to configure exception_notifier in a file in the initializers directory, but I'd be interested in knowing what the 'right' way to do this. (Rails 2.2.2/OSX 10.5)

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