User

Thinking about our projects on TODO List. Right now, it's a public TODO List because anyone can come and post stuff. What if we want to have private TODO lists for each user. That's where we need to have a login system for users to log in.

Clone this exercise

We need to identify a user is with an identifier. And, we need to check password to make sure the user is authorized. We need to store these information in the database.

We are going to name the table User with two basic attributes username and password.

$ rails g model user

In db/migrate/xxxx_create_users.rb,

class CreateUsers < ActiveRecord::Migration[5.0]
  def change
    create_table :users do |t|
      t.string :username
      t.string :password

      t.timestamps
    end
  end
end

Now, that we've created the User table.

Let's create an API endpoint to create a new user (effectively, this is the same as "Sign Up" on the website).

In config/routes.rb,

Rails.application.routes.draw do
  # ...

  # USERS
  post '/users' => 'users#create'

  # ...
end

In app/controllers/users_controller.rb,

class UsersController < ApplicationController
  def create
    @user = User.new(user_params)

    if @user.save
      render 'users/create'
    else
      render json: {
        success: false
      }
    end
  end

  private

    def user_params
      params.require(:user).permit(:password, :username)
    end
end

In app/views/users/create.jbuilder,

json.user do
  json.username @user.username
end

There, our API allows anyone to sign up and create a new account on the website. The account information (username, password) will be stored in the table User in the database.