Model-backed forms in Ruby on Rails - Mini Project: Build & Apply

Model-backed Forms in Rails

📖 Scenario: You are building a simple web app to manage books in a library. Each book has a title and an author. You want to create a form that users can fill out to add new books to the library database.

🎯 Goal: Create a model-backed form in Rails that allows users to add new books with a title and author. The form should save the data to the database when submitted.

📋 What You'll Learn

Create a Book model with title and author attributes

Set up a controller action to handle new book creation

Create a form in the view that is backed by the Book model

Ensure the form submits data correctly to create a new Book record

💡 Why This Matters

🌍 Real World

Model-backed forms are used in web apps to collect and save user data directly tied to database records, like adding books, users, or products.

💼 Career

Understanding model-backed forms is essential for Rails developers to build data-driven web applications efficiently and securely.

1

Create the Book model

Generate a Rails model called Book with string attributes title and author. Write the model class with these attributes.

Ruby on Rails

# Create the Book model class with title and author attributes
# Your code here

Need a hint?

Use rails generate model Book title:string author:string to create the model, then write the class.

2

Add a new action in the Books controller

In the BooksController, add a new action that initializes a new Book object and assigns it to @book.

Ruby on Rails

class Book < ApplicationRecord
  # title:string
  # author:string
end

class BooksController < ApplicationController
  # Your code here
end

Need a hint?

Define a method new inside BooksController and set @book = Book.new.

3

Create the model-backed form in the view

In the new.html.erb view for books, create a form using form_with model: @book. Add fields for title and author, and a submit button.

Ruby on Rails

class Book 

Need a hint?

Use form_with model: @book, local: true do |form| and add label and text_field for title and author.

4

Add the create action to save the book

In BooksController, add a create action that builds a new Book from book_params and saves it. Redirect to the new book page on success. Also add a private method book_params that permits title and author.

Ruby on Rails

class Book 

  
    
    
  
  
    
    
  
  
    
  

Need a hint?

Define create to build and save a new book, redirect on success, and add a private book_params method.