rails api boilerplate example

exception_handler.rb

# app/controllers/concerns/exception_handler.rb

module ExceptionHandler
  extend ActiveSupport::Concern

  class MissingToken  < StandardError; end
  class InvalidToken < StandardError; end
  class AuthenticationError < StandardError; end

  included do
    rescue_from ExceptionHandler::MissingToken, with: :four_twenty_two
    rescue_from ExceptionHandler::InvalidToken, with: :unauthorized_request
    rescue_from ExceptionHandler::AuthenticationError, with: :unauthorized_request
  end

  private

  def four_twenty_two(error)
    json_response({ message: error.message }, :unprocessible_entity)
  end

  def unauthorized_request(error)
    json_response({ message: error.message }, :unauthorized)
  end
end

gistfile1.txt

class ApplicationController < ActionController::API
  include Response
  include ExceptionHandler

  # ...
end

gistfile2.txt

def destroy
  item = Item.find_by(id: params[:id])
  
  raise(ExceptionHandler::NotAuthorized, Message.unauthorized_request)
  if item.destroy
  # .....

message.rb

# app/lib/message.rb

class Message
  def self.not_found(record = 'record')
    "Sorry, #{record} nof found!"
  end

  def self.invalid_credentials
    'Invalid credentials.'
  end

  def self.unauthorized_request
    'Unauthorized request.'
  end

  def self.missing_token
    'Missing token'
  end

  def self.invalid_token
    'Invaild token'
  end
end

response.rb

# app/controllers/concerns/response.rb

module Response
  def json_response(object, status = :ok)
    render json: object, status: status
  end
end