RailErr

A declarative, fire and forget way to handle errors in a rails REST API, and associate each error to an HTTP status code.

Add a rescue_from block to your controller to rescue APIException exceptions and render the appropriate response:

class ApplicationController < ActionController::API
  rescue_from Railerr::APIException do |e|
    render json: { error: e.message }.to_json, status: e.status_code
  end
end

Now just raise your error inside your application and it will automatically be cast to the appropriate HTTP status.

class SomethingReader < ApplicationService
  def call
    # Do Something
    raise Railerr::BadRequstError if params.invalid?
    raise Railerr::NotFoundError, 'Something not found' if something_not_found
  end
end

The above example will result in the following for the BadRequestError:

  # HTTP/1.1 400 Bad Request
  {
    "error": "Bad request"
  }

And raising with a custom message, as for the NotFoundError:

  # HTTP/1.1 404 Not Found
  {
    "error": "Something not found"
  }

Custom API Exception classes can be created through inheritance. You can override HTTP status code and default error message by defining the STATUS_CODE and DEFAULT_MESSAGE constants on your custom Exception

class MyCustomError < APIException
  DEFAULT_MESSAGE = 'Custom error message' # Overrides the message inherited from APIException
  STATUS_CODE = Status::HTTP_400_BAD_REQUEST # Overrides the status code inherited from APIException
end