bigmac12 / api_me

RESTful Api resources in Rails

ApiMe

This gem is currently a work in progress, follows semver, and may change significantly until version 1.0

A gem for building RESTful Api resources in Rails

ApiMe provides a set of generators and base classes to assist with building Restful API's in Ruby on Rails.

Details

Api controllers use the fantastic Pundit gem for authorization and parameter whitelisting, Active Model Serializers ver 0.8 for resource serialization, and SearchObject for list filtering. The model, filter, serializer, and policy that the controller uses by default can all be overriden, along with other optional parameters.

The primary goal of this gem was to keep things simple so that customization is fairly straight forward by separating concerns and providing overrides. Reusing existing libraries was a primary goal during the design, hence the overall simplicity of this gem. We currently use this gem internally at Inigo and are committed to its ongoing maintenance.

Installation

Add the gem to your Gemfile: gem api_me.

Run bundle install to install it.

Run rails generate api_me:install to install api_me.

You are now setup!

Usage

rails generate api_me:resource user organization:belongs_to name:string ...

this generates the following:

• app/controllers/api/v1/users_controller.rb
• app/policies/user_policy.rb
• app/serializers/user_serializer.rb

and also essentially calls:

• rails generate model user organization:belongs_to name:string ... Which generates the model et al as specified.

users_controller.rb:

class UsersController < ApplicationController
  include ApiMe

end

POST (create) and PUT (update) requests are expected to post parameters to the singular underscored name of the model by default (I.E. {"user": {"name": "Test"}} for a user model), but this can be overriden by overriding def params_klass_symbol, or more in-depth by overriding def object_params. If def object_params is overriden, parameters are also expected be whitelisted inside of this method.

models/user.rb:

# Standard Rails generator used
class User < ActiveRecord::Base
  belongs_to :organization
end

policies/user_policy.rb (See Pundit for details):

class UserPolicy < ApplicationPolicy
  # Authorizes what parameters will be whitelisted, see [Pundit](https://github.com/elabs/pundit) for details
  def permitted_attributes
    [:id, :organization_id, :name]
  end

end

serializers/user_serializer.rb (See Active Model Serializers ver 0.8 for details):

class UserSerializer < ActiveModel::Serializer
  attributes :id, :name, :organization_id
end

filters/user_filter.rb (See SearchObject for details):

require 'search_object'

class UserFilter < ApiMe::BaseFilter
  include ::SearchObject.module #required

  # Add custom filter logic here
  # Ex:
  #   option(:search) { |scope, value| scope.where("username LIKE ?", "%#{value}%") }
end

The ApiMe::BaseFilter is called if no filter exists for the resource, by default the base filter provides filtering by ids for convenience. I.E a GET to /api/v1/users?ids%5B%5D=1&ids%5B%5D=3 would return users filtered by ids of 1 and 3. All other filters are expected by default to be located at params[:filters] and not at the base level.

Overrides

Overriding the default model class, serializer class, filter class, and filter parameter can be done like so:

users_controller.rb:

class UsersController < ApplicationController
  include ApiMe

  model FakeUser
  serialzier RealUserSerialzier

  def filter_klass
    FancyUserFilter
  end

  def filter_params
    params[:meta][:filters]
  end
end

Todo:

• Add the ability to specify the api controller path (I.E. app/controllers/api/v2)
• Add the ability to inject the resource route into the routes file in the resource generators

License

Copyright (c) 2014, Api Me is developed and maintained by Sam Clopton, and is released under the open MIT Licence.