How to configure rollbar-gem to work with your Rails app | Support Level: Supported

Quick Start

Run the following command from your Rails root:

$ rails generate rollbar POST_SERVER_ITEM_ACCESS_TOKEN

Be sure to replace POST_SERVER_ITEM_ACCESS_TOKEN with your project's post_server_item access token, which you can find in the Rollbar.com interface.

That will create the file config/initializers/rollbar.rb, which initializes Rollbar and holds your access token and other configuration values.

If you want to learn more about how to configure this file, you can refer to the Configuration Reference.

If you want to store your access token outside of your repo, run the same command without arguments and create an environment variable ROLLBAR_ACCESS_TOKEN that holds your server-side access token:

$ rails generate rollbar

For Heroku users:

If you're on Heroku, you can store the access token in your Heroku config:


That's all you need to use Rollbar with Rails.

Test your installation

If you're not using Rails, you may first need to add the following to your Rakefile:

require 'rollbar/rake_tasks'

You may also need to add an :environment task to your Rakefile if you haven't already defined one. At a bare minimum, this task should call Rollbar.configure() and set your access token.

task :environment do
  Rollbar.configure do |config |
    config.access_token = '...'

To confirm that it worked, run:

$ rake rollbar:test

This will raise an exception within a test request; if it works, you'll see a stacktrace in the console, and the exception will appear in the Rollbar dashboard.

Rails booting process

Rails doesn't provide a way to hook into its booting process, so we can't catch errors during boot out of the box. To report these errors to Rollbar, make the following changes to your project files.

First, move your config/initializers/rollbar.rb file to config/rollbar.rb. Then be sure your config/environment.rb looks similar to this:

# config/environment.rb

require File.expand_path('../application', __FILE__)
require File.expand_path('../rollbar', __FILE__)

notify = ->(e) do
    Rollbar.with_config(use_async: false) do
    Rails.logger.error "Synchronous Rollbar notification failed.  Sending async to preserve info"

rescue Exception => e

How this works: first, Rollbar config (which is now at config/rollbar.rb is required). Later, Rails.application/initialize statement is wrapped with a begin/rescue and any exceptions within will be reported to Rollbar. We first try to send the notification synchronously since, with our app failing to boot, it is likely the async handler relies on the app booting, and will not process the notification.

Rails runner command

We aren't able to instrument rails runner directly, but we do provide a wrapper, rollbar-rails-runner, which you can use to capture errors when running commands in a rails runner-like way. For example:

$ bundle exec rollbar-rails-runner 'puts User.count'

If an error occurs during that command, the exception will be reported to Rollbar.


For more information on rollbar-gem, please see the docs here.