REST API with Ruby on Rails and ReactJS

Question

I'm currently working on building a simple REST API using Ruby on Rails. I noticed that a lot of the things I did were a bit redundant, especially the models. Just to clarify: I want this to be a REST API which returns JSON, without any views (I want to be able to access it from different applications, mainly Apache Cordova). Within Cordova I wanted to use ReactJS.

Sadly, my Rails controllers all look like this:

class StudentsController < ApplicationController
  def index
    @students = Student.all
    render json: @students
  end

  def create
    if @student.present?
      render nothing: true, status: :conflict
    else
      @student = Student.new(student_params)
      if @student.save
        render json: @student
      else
        render nothing: true, status: :bad_request
      end
    end
  end

  def show
    @student = Student.find(params[:id])
    render json: @student.classes
  end

  def update
    @student = Student.find(params[:id])
    @student.update(student_params)
    if @student.save
      render json: @student
    else
      render nothing: true, status: :bad_request
    end
  end

  def delete
    if Student.destroy(params[:id])
      render nothing: true, status: :ok
    else
      render nothing: true, status: :bad_request
    end
  end

  private
    def student_params
      params.permit(:first_name, :last_name, :grade_id)
    end
end

I literally got three of them with only the classname changed. Is there a smarter way to organize this? I may have to change override some functions, but some functions will be identical.

I also have a few database relationships, for example grades and classes to teachers and students. Does anyone have some information about best practices for this? I seem to be creating a lot of "relationship" tables for these many-to-many relationships.

For the RoR Rest API Part I found this tutorial.

Answer 1

I think this is an interesting idea, although I haven't personally used it when building REST APIs.

Here's some code which shows how it could be done.

I tested the following code to ensure that it works. To test it:

1. make a todo model with a :name column
2. add resources :todos to the routes
3. visit localhost:3000/todos

...

# app/controllers/todos_controller.rb
class TodosController < ApplicationController
  include GenericController
  RecordClass = Todo
  def record_params
    params.require(:todo).permit(:name)
  end
end

You can see that there are only two points of customization in each controller. You'll have to specify the RecordClass and your secure parameters method.

The following "generic controller" was built using Rails' default scaffold controller. You can customize it to follow your own default controller logic.

# app/controllers/generic_controller.rb
module GenericController

  before_action :set_instance, only: [:show, :edit, :update, :destroy]

  def index
    @records = RecordClass.all
  end

  def show
  end

  def new
    @record = RecordClass.new
  end

  def edit
  end

  def create
    @record = RecordClass.new(record_params)
    respond_to do |format|
      if @record.save
        format.html { redirect_to @record, notice: '#{RecordClass} was successfully created.' }
        format.json { render :show, status: :created, location: @record }
      else
        format.html { render :new }
        format.json { render json: @record.errors, status: :unprocessable_entity }
      end
    end
  end

  def update
    respond_to do |format|
      if @record.update(record_params)
        format.html { redirect_to @record, notice: '#{RecordC;ass} was successfully updated.' }
        format.json { render :show, status: :ok, location: @record }
      else
        format.html { render :edit }
        format.json { render json: @record.errors, status: :unprocessable_entity }
      end
    end
  end

  def destroy
    @record.destroy
    respond_to do |format|
      format.html { redirect_to records_url, notice: #{'RecordClass} was successfully destroyed.' }
      format.json { head :no_content }
    end
  end

  private
    def set_record
      @record = RecordClass.find(params[:id])
    end