MERN Challenge: Book Search Engine
Your Challenge this week is emblematic of the fact that most modern websites are driven by two things: data and user demands. This shouldn’t come as a surprise, as the ability to personalize user data is the cornerstone of real-world web development today. And as user demands evolve, applications need to be more performant.
This week, you’ll take a fully functioning Google Books API search engine built with a RESTful API, and refactor it to be a GraphQL API built with Apollo Server. The app was built using the MERN stack, with a React front end, MongoDB database, and Node.js/Express.js server and API. It’s already set up to allow users to save book searches to the back end.
To fulfill the Challenge, you’ll need to do the following:
Set up an Apollo Server to use GraphQL queries and mutations to fetch and modify data, replacing the existing RESTful API.
Modify the existing authentication middleware so that it works in the context of a GraphQL API.
Create an Apollo Provider so that requests can communicate with an Apollo Server.
Deploy the application to Heroku.
Make sure to clone the starter code repository and make your own repository with the starter code. Do not fork the starter code repository!
Before you start, clone the starter code ( https://github.com/coding-boot-camp/solid-broccoli).
AS AN avid reader
I WANT to search for new books to read
SO THAT I can keep a list of books to purchase
GIVEN a book search engine
WHEN I load the search engine
THEN I am presented with a menu with the options Search for Books and Login/Signup and an input field to search for books and a submit button
WHEN I click on the Search for Books menu option
THEN I am presented with an input field to search for books and a submit button
WHEN I am not logged in and enter a search term in the input field and click the submit button
THEN I am presented with several search results, each featuring a book’s title, author, description, image, and a link to that book on the Google Books site
WHEN I click on the Login/Signup menu option
THEN a modal appears on the screen with a toggle between the option to log in or sign up
WHEN the toggle is set to Signup
THEN I am presented with three inputs for a username, an email address, and a password, and a signup button
WHEN the toggle is set to Login
THEN I am presented with two inputs for an email address and a password and login button
WHEN I enter a valid email address and create a password and click on the signup button
THEN my user account is created and I am logged in to the site
WHEN I enter my account’s email address and password and click on the login button
THEN I the modal closes and I am logged in to the site
WHEN I am logged in to the site
THEN the menu options change to Search for Books, an option to see my saved books, and Logout
WHEN I am logged in and enter a search term in the input field and click the submit button
THEN I am presented with several search results, each featuring a book’s title, author, description, image, and a link to that book on the Google Books site and a button to save a book to my account
WHEN I click on the Save button on a book
THEN that book’s information is saved to my account
WHEN I click on the option to see my saved books
THEN I am presented with all of the books I have saved to my account, each featuring the book’s title, author, description, image, and a link to that book on the Google Books site and a button to remove a book from my account
WHEN I click on the Remove button on a book
THEN that book is deleted from my saved books list
WHEN I click on the Logout button
THEN I am logged out of the site and presented with a menu with the options Search for Books and Login/Signup and an input field to search for books and a submit button
Let’s start by revisiting the web application’s appearance and functionality.
As you can see in the following animation, a user can type a search term (in this case, “star wars”) in a search box and the results appear:
Animation shows “star wars” typed into a search box and books about Star Wars appearing as results.
The user can save books by clicking “Save This Book!” under each search result, as shown in the following animation:
Animation shows user clicking “Save This Book!” button to save books that appear in search results. The button label changes to “Book Already Saved” after it is clicked and the book is saved.
A user can view their saved books on a separate page, as shown in the following animation:
The Viewing Lernantino’s Books page shows the books that the user Lernaninto has saved.
In order for this application to use a GraphQL API, you’ll need to refactor the API to use GraphQL on the back end and add some functionality to the front end. The following sections contain details about the files you’ll need to modify on the back end and the front end.
Make sure to study the application before building upon it. Better yet, start by making a copy of it. It’s already a working application—you’re converting it from RESTful API practices to a GraphQL API.
You’ll need to complete the following tasks in each of these back-end files:
auth.js: Update the auth middleware function to work with the GraphQL API.
server.js: Implement the Apollo Server and apply it to the Express server as middleware.
Apollo Server recently migrated to Apollo Server 3. This major-version release impacts how Apollo Server interacts in an Express environment. To implement Apollo Server 2 as demonstrated in the activities, you MUST use the following script npm install email@example.com to install Apollo Server 2. Alternately, to migrate to the latest version of Apollo Server, please refer to the Apollo Server Docs on Migrating to Apollo Server 3 (Links to an external site.) and Apollo Server Docs on Implementing Apollo Server Express with v3 (Links to an external site.). Note that if you are using Apollo Server 3 you are required use await server.start() before calling server.applyMiddleware.
index.js: Export your typeDefs and resolvers.
resolvers.js: Define the query and mutation functionality to work with the Mongoose models.
typeDefs.js: Define the necessary Query and Mutation types:
me: Which returns a User type.
login: Accepts an email and password as parameters; returns an Auth type.
addUser: Accepts a username, email, and password as parameters; returns an Auth type.
saveBook: Accepts a book author’s array, description, title, bookId, image, and link as parameters; returns a User type. (Look into creating what’s known as an input type to handle all of these parameters!)
removeBook: Accepts a book’s bookId as a parameter; returns a User type.
savedBooks (This will be an array of the Book type.)
bookId (Not the _id, but the book’s id value returned from Google’s Book API.)
authors (An array of strings, as there may be more than one author.)
user (References the User type.)
You’ll need to create the following front-end files:
queries.js: This will hold the query GET_ME, which will execute the me query set up using Apollo Server.
LOGIN_USER will execute the loginUser mutation set up using Apollo Server.
ADD_USER will execute the addUser mutation.
SAVE_BOOK will execute the saveBook mutation.
REMOVE_BOOK will execute the removeBook mutation.
Additionally, you’ll need to complete the following tasks in each of these front-end files:
App.js: Create an Apollo Provider to make every request work with the Apollo server.
Use the Apollo useMutation() Hook to execute the SAVE_BOOK mutation in the handleSaveBook() function instead of the saveBook() function imported from the API file.
Make sure you keep the logic for saving the book’s ID to state in the try…catch block!
Remove the useEffect() Hook that sets the state for UserData.
Instead, use the useQuery() Hook to execute the GET_ME query on load and save it to a variable named userData.
Use the useMutation() Hook to execute the REMOVE_BOOK mutation in the handleDeleteBook() function instead of the deleteBook() function that’s imported from API file. (Make sure you keep the removeBookId() function in place!)
SignupForm.js: Replace the addUser() functionality imported from the API file with the ADD_USER mutation functionality.
LoginForm.js: Replace the loginUser() functionality imported from the API file with the LOGIN_USER mutation functionality.
MERN Challenge: Book Search Engine