Provides friendly responses for validation and server errors to RESTful Rails JSON APIs.


Add this line to your application's Gemfile:

gem 'friendly-responses'

And then execute:

$ bundle

Or install it yourself as:

$ gem install friendly-responses


Simply include the FriendlyResponses module in your controller to enable friendly-responses. You may prefer to include this module in your application controller or a controller your API controllers will subclass as shown in the example below.

# app/controllers/api_controller.rb
class ApiController < ApplicationController
  include FriendlyResponses
  # ...custom controller code

Validation errors

The friendly-responses gem provides a convenient way to respond with validation errors that are actually useful to API clients. In the example controller action below, we call the #respond_with_invalid_record method with our model to create a friendly error response.

# app/controller/frienemies_controller.rb
class FrienemiesController < ApiController
  def create
    @frienemy = frienemy_params

      render action: 'show', status: :created
      respond_with_invalid_record @frienemy

Here is an example of a request that triggers a validation error and a friendly response.

$ curl -i -X POST http://localhost:3000/frienemies \
    -H 'Accept: application/json' \
    -H 'Content-Type: application/json' \
    -d '{ "frienemy": { "name": "Donald Trump" } }'

  "errors": [
    "Why you can't have a frienemy for no reason"
  "frienemy": {
    "errors": {
      "why": [
        "you can't have a frienemy for no reason"


After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to


Bug reports and pull requests are welcome on GitHub at


The gem is available as open source under the terms of the MIT License.