Why Rails API mode exists - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a new Rails API-only application.

Ruby on Rails

rails new my_api_app --[1]

Drag options to blanks, or click blank then click option'

Afull

Bminimal

Capi

Dweb

Attempts:

3 left

💡 Hint

Common Mistakes

Using --full creates a full Rails app with views and assets.

Using --web is not a valid Rails new flag.

Using --minimal is not a recognized option.

The --api flag creates a Rails application optimized for APIs by excluding views and assets.

2fill in blank

medium

Complete the sentence explaining why Rails API mode excludes some features.

Ruby on Rails

Rails API mode excludes [1] and assets to make the app smaller and faster.

Drag options to blanks, or click blank then click option'

Aviews

Bmigrations

Ccontrollers

Dmodels

Attempts:

3 left

💡 Hint

Common Mistakes

Thinking models are excluded, but models are still used.

Controllers are still needed to handle requests.

Migrations are part of database setup and not excluded.

Rails API mode excludes views and assets because APIs usually send data, not HTML pages.

3fill in blank

hard

Fix the error in this Rails API controller method to respond with JSON.

Ruby on Rails

def show
  user = User.find(params[:id])
  render [1]: user
end

Drag options to blanks, or click blank then click option'

Atext

Bhtml

Cxml

Djson

Attempts:

3 left

💡 Hint

Common Mistakes

Using html renders a web page, not JSON data.

Using text or xml is not standard for Rails APIs.

In API mode, responses are usually JSON, so render json: user sends user data as JSON.

4fill in blank

hard

Fill both blanks to configure middleware for a Rails API app.

Ruby on Rails

class Application < Rails::Application
  config.api_only = [1]
  config.middleware.use [2]
end

Drag options to blanks, or click blank then click option'

Atrue

Bfalse

CActionDispatch::Cookies

DActionDispatch::Static

Attempts:

3 left

💡 Hint

Common Mistakes

Setting api_only to false disables API mode.

Adding Static middleware is for serving files, not cookies.

Setting config.api_only = true enables API mode. Adding ActionDispatch::Cookies middleware allows cookie support if needed.

5fill in blank

hard

Fill all three blanks to create a simple JSON response in a Rails API controller.

Ruby on Rails

class GreetingsController < ApplicationController
  def hello
    message = { [1]: [2] }
    render [3]: message
  end
end

Drag options to blanks, or click blank then click option'

Agreeting

B"Hello, world!"

Cjson

Dtext

Attempts:

3 left

💡 Hint

Common Mistakes

Using text instead of json in render.

Forgetting to quote the string value.

Using an unrelated key name.

The hash key is greeting, the value is the string "Hello, world!", and render json: message sends JSON response.