grape error handling

v1.rb

# app/controllers/api/v1.rb

class Api::V1 < Grape::API
  class Grape::Middleware::Error
    def error_message(code, text)
      {
        :error => {
          :code => code,
          :message => text
        }
      }.to_json
    end
  end

  rescue_from Api::V1::BaseAPI::InvalidToken do |e|
    rack_response(error_message(50, 'invalid access token provided'), 401)
  end

  rescue_from Api::V1::BaseAPI::AccessDenied do |e|
    rack_response(error_message(60, 'access denied'), 403)
  end

  rescue_from ActiveRecord::RecordNotFound do |e|
    rack_response(error_message(70, 'not found'), 404)
  end

  rescue_from Grape::Exceptions::ValidationErrors do |e|
    rack_response(error_message(20, e.message), e.status)
  end

  rescue_from :all do |e|
    if Rails.env.development?
      raise e
    else
      rack_response(error_message(500, 'internal server error'), 500)
    end
  end

  # mounts goes here
end