GraphQL API with React.js

Many new APIs are moving away from REST and embracing the change to GraphQL. GitHub's API V4 is one example of this, and that's because GraphQL offers a lot more flexibility when querying for data. This tutorial will go over how to incorporate and make queries using React and a modern GraphQL API.

For this demo, we'll be using AniLists's V2 API to get a list of anime titles and their cover images. I chose this API because it's ready to use without any configurations or OAuth tokens. GitHub's V4 API works in a similar way, but you'll need to create an access token and include it with each request. I'll also be using axios to make our queries, this should give a general overview on the basics of using GraphQL and React.

GraphQL API with React Demo ( view source )

To keep things simple, I'm going to use create-react-app to start things off. Once you have create-react-app installed, we can create our app.

# Create the app
npx create-react-app anime-graphql

cd anime-graphql

# Install axios, use 'npm install axios' if you don't use yarn
yarn add axios

# Start the app, browse to http://localhost:3000/
yarn start

We now have our generic app running and axios is the only additional package we needed to install. Open up src/App.js and strip out the boilerplate JSX until we're left with this

import React, { Component } from 'react';
import './App.css';

class App extends Component {
  render() {
    return (
      <div>

      </div>
    );
  }
}
export default App;

GraphiQL Explorer

AniList has some pretty good documentation for their API, including an example GraphQL query. Their example is to get a single anime title by providing an ID. If we want to get a big list of cover images, we'll need to check out their GraphiQL explorer. In order to use this feature, you'll need to register for free with AniList. You only need to register if you want to play with their explorer, it's not required for our React app.

Most GraphQL APIs will come with an explorer where you can make test queries and search for possible values. Let's check out AniList's https://anilist.co/graphiql.

GraphiQL Preview

The left pane is where you can make a query and the right pane is the result once you hit the "play" button. The far right has a Documentation Explorer which shows all the different fields and values. The left pane also has an auto-complete feature, if you hit control+space within a bracket, it will show a popup of all available fields. This is one of the best features of a GraphQL API since you can quickly and easily make a query and just copy and paste it into your app.

We can plug in a test query to see this in action. Copy the following into the left pane and hit play

{
  Media(id: 1) {
    id
    title {
      romaji
      english
      native
    }
  }
}

This will make a Media query with id: 1, and get all the titles associated with it. If you put your cursor above title and hit control+space, you can select any other field from the auto-complete and query for that as well. A GraphQL query will only return the fields you ask for, which eliminates the over-fetching of unnecessary data.

To get a list of titles, we'll need to query for a Page and then add media() within that query. Search for Page in the Document Explorer and it will list some additional information. Our query will look something like this:

{
  Page {
    media(isAdult: false, sort: POPULARITY_DESC) {
      id
      title {
        romaji
        english
      }
      coverImage {
        large
      }
    }
  }
}

Note that media() requires at least one argument to work, so we'll set isAdult to false and add a sort. We can pass additional filters into the media query, like the season and seasonYear. Play around with the auto-complete and the documentations to find available fields. We're also asking for the coverImage, which will be a url to the image.

Making the Query with React.js

Once we are happy with the query, we can set things up in our React app. Be sure to import axios and set up some initial state. Using async/await, we create a function called getAnime to request our data. An async function is newer syntax for handling Promises in JavaScript.

// Be sure to import axios
import axios from 'axios';

class App extends Component {

state = {
  error: null,
  isLoaded: false,
  items: []
}

getAnime = async (query, variables) => {
  try {
    const response = await axios.post('https://graphql.anilist.co', {
      query,
      variables
    });

    // Log the response so we can look at it in the console
    console.log(response.data)

    // Set the data to the state
    this.setState(() => ({
      isLoaded: true,
      items: response.data.data.Page.media
    }));

  } catch (error) {
    // If there's an error, set the error to the state
    this.setState(() => ({ error }))
  }
}

The one and only AniList endpoint is https://graphql.anilist.co which we have to POST to. Using axios.post(), we pass in the endpoint as the first argument and an object with the query as the second argument. When the query is complete, we set the data to the response constant and update the state. Let's add a componentDidMount() lifecycle method and call this.getAnime() with our query.

componentDidMount() {

  // This is the GraphQL query
  const query = `
  query {
    Page {
      media(isAdult: false, sort: POPULARITY_DESC) {
        id
        title {
          romaji
          english
        }
        coverImage {
          large
        }
      }
    }
  }
  `;

  // These variables are optional, leave empty for now
  const variables = {};

  // We call the method here to execute our async function
  this.getAnime(query, variables)

}

For the query constant, we can basically copy out what we have from the GraphiQL explorer and paste it into a template string, adding query before the first bracket. The variables constant is optional and it's a way of passing variables into the query. Finally we call this.getAnime() and pass in the variables. Open up your browser's inspector and head into the Network tab, you should see the request and the response in the console!

Rendering the Data

With the data in hand, the hard part is over. Only thing left is to update our render() method and map out our cover images. We'll also create a simple component to house each item.

// Our simple component for each grid item
const GridItem = (props) => (
  <div className="grid__flex">
    <img className="grid__img" src={props.image} />
  </div>
)

class App extends Component {
...

// The new render()
render() {

  const { error, isLoaded, items } = this.state;

  if (error) {
    return <div>{error.message}</div>;
  } else if (!isLoaded) {
    return <div>Loading...</div>;
  } else {

    return (
      <div className="grid">
        {items.map(item => (
          <GridItem key={item.id} image={item.coverImage.large} />
        ))}
      </div>
    );

  }
}

You should be seeing the images in your browser! Let's spice things up a bit with some CSS Grid, open up src/App.css and replace with the following.

html, body {
  margin: 10px;
}

.grid {
  display: grid;
  grid-gap: 10px;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  grid-auto-flow: dense;
}

.grid__flex {
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
}

.grid__img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

Nice, the images should now be showing in a responsive grid! Now try creating a new query with the explorer and copy/paste it into the React App. You can also try out GitHub's GraphQL API and play with their explorer as well, everything works pretty much the same except you'll need to generate an OAuth token and add it to your request headers. Here's a sample of what a GitHub query function looks like.

getRepo = async (query, variables) => {
  try {
    const response = await axios.post(
      "https://api.github.com/graphql",
      {
        query: gitQuery,
        variables: variables
      },
      {
        headers: {
          Authorization: "token YOUR_TOKEN_HERE"
        }
      }
    );
    console.log(response.data);
  } catch (error) {
    console.log(error);
  }
};

GraphQL API with React Tutorial ( view source )