👋 Welcome to Lift-off IV!
Lift-off IV: Mutations is a certifying course!By completing this course, you're getting one step closer to earning your Graph Developer - Associate Certification.
Good to see you here for Lift-off Part IV! We've been hard at work on our Catstronauts app, diving into GraphQL on both the server and client side.
So far, we've only dealt with retrieving data from our API. Now it's time to switch gears and work on modifying our data with GraphQL mutations.
Each track in our app displays the number of times it's been viewed. We want to increment this number every time a user visits the track page from the homepage.
To do this, we'll update our schema to include mutations, learning best practices for our mutation responses. We'll write our resolvers to handle both successful responses and errors. And lastly on the client-side, we'll use a React hook called
useMutation to send our request to the GraphQL server.
Clone the repository
In the directory of your choice with your preferred terminal, clone the app's starter repository:
git clone https://github.com/apollographql/odyssey-lift-off-part4
This repo picks up where Lift-off III left off. Our project is a full-stack app with the backend app in the
server/ directory and the frontend app in the
You'll also find a
final/ folder that contains the final state of the project once you've completed the course. Feel free to use it as a guide!
Here's the file structure:
📦 odyssey-lift-off-part4┣ 📂 client┃ ┣ 📂 public┃ ┣ 📂 src┃ ┣ 📄 README.md┃ ┣ 📄 package.json┣ 📂 server┃ ┣ 📂 src┃ ┃ ┣ 📂 datasources┃ ┃ ┃┣ 📄 track-api.js┃ ┃ ┣ 📄 index.js┃ ┃ ┣ 📄 schema.js┃ ┃ ┣ 📄 resolvers.js┃ ┣ 📄 README.md┃ ┣ 📄 package.json┣ 📂 final┃ ┣ 📂 client┃ ┣ 📂 server┗ 📄 README.md
Now, open the repository in your favorite IDE.
Note: The examples in this course use
npm, but you're welcome to use
yarn if you prefer.
Let's start with the server app.
In a terminal window, navigate to the repo's
server directory and run the following to install dependencies and run the app:
npm install && npm start
If all goes well, you'll see the installation complete and a message in the console indicating that the server is running.
Next, the client app.
In a new terminal window, navigate to the repo's
client directory and run the following to install dependencies and start the app:
npm install && npm start
The console should show a bunch of output and a link to the running app at
localhost:3000. You can navigate to http://localhost:3000 in the browser and see our homepage, which shows multiple track cards.
Setting up the Explorer
To write our queries, we'll be using the Explorer page in Apollo Sandbox. The Explorer is free to use, and it provides awesome development features like interactive query building, query history, and response hints. This will make building our queries fast and fun.
To open the Explorer in Apollo Sandbox, you can
cmd+click on the URL in your terminal (from starting the server) to open it in your browser, or you can open it here: http://localhost:4000.
In the browser, we can see that our server is running successfully, with a message inviting us to query it. Let's click Query your server to see our graph in action with Apollo Sandbox.
Let's get to it!