A simple plugin to handle, log, and customize production errors

error-handling, error-monitoring, rails, slack
gem install errdo -v 0.12.14



Gem Version master build Code Climate Test Coverage

Because sometimes your users get ERRors, and you want to DO something about it.

This gem is meant to be an simple all-in-one error solution that's embedded right into your rails application. It's an alternative to the complications of installing multiple gems to track, record, and notify yourself of errors that your users encounter. (Or paying for a big solution when you only want something simple.)

I'm a big believer that every single app with a production server, whether it has users or not, should have some way to track errors. It leads to better code and can prevent a critical error from causing a mass exodus of users (something I have personal experience with).

Big thanks to the contributors to the rails admin and devise gems, whose beautiful code has been very helpful in trying to make this gem as modular and expandable as possible.

To the good part.

If you're updating from 0.10.x to 0.11.x, it's a breaking change. You will have to either run rails generate errdo:install again, resetting the errors table to incorporate new fields, or add the field importance, type string to your error model with a migration:

def change
  add_column :errors, :importance, :string, default: 'error'

If you're updating from 0.11.x to 0.12.x, it's a breaking change. You will have to either run rails generate errdo:install again, resetting the errors table to incorporate new fields, or change over the fields

def up
    change_column :errors, :exception_class_name, :text
    change_column :errors, :exception_message, :text
    change_column :errors, :host_name, :text
    change_column :errors, :url, :text
    change_column :error_occurrences, :user_agent, :text
    change_column :error_occurrences, :query_string, :text
def down
    change_column :errors, :exception_class_name, :string
    change_column :errors, :exception_message, :string
    change_column :errors, :host_name, :string
    change_column :errors, :url, :string
    change_column :error_occurrences, :user_agent, :string
    change_column :error_occurrences, :query_string, :string

Quickstart Guide

Put gem 'errdo' in your Gemfile and run bundle install

Next, you need to run the installer with

$ rails generate errdo:install

This will create an initializer called "errdo.rb" with configuration options inside. It's useful to read these options to customize to get exactly what you want.

If you want to log the errors into a database, you'll now need to run

$ rails generate errdo MODEL where MODEL is the optional error name you want to log. If left blank, it will default to "error". Run rake db:migrate

To be able to see a list of all the errors in your application, mount the engine: mount Errdo::Engine => "/errdo" where you can replace "/errdo" with whatever you want.

To link the error index page in your application, the route will be errdo.root_path

This should be good enough to get everything working on a basic level.

To test this in your development environment, make sure you set config.consider_all_requests_local = false in your development.rb

And then, you know, break something.


To authenticate, you must pass a block to the authenticate_with method in the initializer. If you're using devise, the simple command is

config.authenticate_with do
      warden.authenticate! scope: :user

Otherwise, you'll want to pass a block that authenticates the current user.

To keep track of the user that encounters an error, you'll want to set the current_user method in the initializer.

By default, it's nil, which means that logged in users aren't recorded with the errors (Though the user-agent always is).

If you want to be able to link to your user's page (and have it clickable from the error index page for quick navigation), set the config.user_show_path to the URL helper for your user's show page. For example, in a normal application, this would be :user_path


You probably don't want to rely on obfuscation to stop users from seeing your developer/admin side error index table.

Similarly to authentication, you can pass a block to authorize with. For example, you can pass a direct redirect call:

config.authorize_with do
  redirect_to root_path unless warden.user.try(:is_admin?)

If you're using CanCanCan, you can just pass :cancan as an option: config.authorize_with :cancan

Notification Integrations

Right now, only slack is supported.


To get this working, you must set up a slack integration on your team's slack page.

To get webhook url you need:

  1. Go to https://slack.com/apps/A0F7XDUAZ-incoming-webhooks
  2. Choose your team, press configure in configurations press add configuration
  3. Choose channel, press "Add Incoming WebHooks integration"

Now, set a hash of all your slack values

config.notify_with slack: {  webhook: "WEBHOOK-URL",
                            icon: ":boom:",
                            channel: "#general"}

You can set a custom slack emoji icon and name for the bot that posts in your channel. See the initializer for more information. You can also set which channel Errdo posts in.

In the future, more keys will be added to this hash for more integrations. Working on it!

Manual Logging

There are cases in every app when things that go wrong are caught before they percolate up to the user. In these cases, it's helpful to have a way to manually log errors.

if @user.update(params)
  flash[:success] = t(:success)
  flash[:error] = t(:error)

The logging methods are:

  1. Errdo.log(exception, string, params)to log to database only with importance level of 'info'
  2. Errdo.notify(exception, string, params)to send notifications only
  3. Errdo.warn(exception, string, params)to send notifications and log, with an importance level of 'warning'
  4. Errdo.error(exception, string, params)to send notifications and log, with an importance level of 'error'

The last exception, string, and hash as method parameters will be logged along with the error.

Non Web Requests

Errdo has the default ability to log exceptions in rake tasks. If you don't want this functionality, set

config.log_task_exceptions = false

in the errdo.rb initializer.

ActiveJobs are supported with no extra effort.


By default, the words password passwd password_confirmation secret confirm_password secret_token are all scrubbed from the params before storing the error in the database. If you need something else scrubbed, you can customize this list of params in the initializer

config.dirty_words += ["custom_param"]

Notice the += instead of just =


By default, 404 errors are logged and notified. To turn this off, set

config.log404 = true

in the initializer.

By default, errors are ignored (for notification only) if they happen within 5 minutes of the last identical error. This can be changed by setting

config.ignore_time = 5.minutes


If there's a big feature you want, I would hope you would consider contributing.

This gem happens on the brink of failure in the app. Exceptions in this gem lead to bad user experience, so everything is very well tested in minitest. Everything submitted should have 95%+ code test coverage, at the very least.

As far as style, I follow a subset of the ruby style guide. There's a rubocop file in the repo that's customized. I would highly appreciate if it you follow the style guide, to keep things clean. Honestly, though, I probably won't reject something just because of style.

That being said, I would love your help!

Bug reports

Because bugs are so catastrophic at this level of the app, I would really really really appreciate it if you could submit bugs that you encounter. I will be able to get to them quickly.

Being mean to my code

I'm doing this project as a fun side project, so I'm trying to make the code as beautiful and DRY as possible. If you have a good time ripping apart people's code, feel free to message me with any things you think I can do better in the app. I love to learn and I would love to hear your feedback.


If you think of something cool that you would use in your app, let me know on github preferably, even if you don't want to work on it! I'm always open to new ideas.


I'm using Semantic Versioning. That being said, this gem is currently in beta stage (0 as the major release). Because of this, many of the changes in minor version (The middle number) will be breaking changes. These should become a lot less frequent, but the core functionality is still sort of being figured out. I will be including in the README specific instructions on how to upgrade each minor beta version, so make sure to check here if something breaks.

Also, I'll be answering any question I get on the issues page, or any email. Until the first major release (1.0.0), please pardon my dust!

This project rocks and uses MIT-LICENSE.