Using Gadget with React 

Gadget has React bindings that use the API client generated for simple-blog-example. These bindings are built on top of the React bindings provided by urql, but with the same type safety guarantees as the generated client.

Installation 

To use your Gadget client with React, you must install both React and the React bindings.

npm install @gadgetinc/react react

yarn add @gadgetinc/react react

Client setup 

Authentication 

The urql client that the simple-blog-example JS client provides is pre-configured to connect to the right Gadget platform GraphQL endpoint and uses the same authentication mechanism that the outer Gadget client uses. If you configure the Gadget client to use a browser session, the urql client will use the same browser session. If you configure you Gadget client to use API key authentication, the urql client will use that same API key.

React is a client side framework and your code is likely to be visible to all the users of your application. For this reason, Gadget recommends using Session Cookie based authentication for accessing the Gadget API. You shouldn't use an API key that has write permissions for authenticating as that API key will be available to any client and ripe for abuse. You can instead use session-based authentication where users must log in to get privileges, or you can leave the client in the unauthenticated mode and grant permissions to read some backend data to the Unauthenticated role.

See the Authentication documentation for more details on safely giving users access to your application.

Creating the client for React apps 

Once your simple-blog-example package has been installed, create an instance of the Client class in a shared file somewhere:

This client will be shared by all your React components, so it's best to put this code outside any particular component, or within one of your root components where it can be shared. Be sure to select the appropriate authentication mode for your use case.

import { Client } from "@gadget-client/simple-blog-example";
export const api = new Client({
  authenticationMode: { browserSession: true },
});

export const api = new Client();

Providing the Client 

Once your client is installed and set up, you must provide an urql client to your React components using the Gadget React provider. Your Client instance exposes the urql client object at .connection.currentClient.

1import { Provider } from "@gadgetinc/react";
2import { api } from "shared/api";
3const App = () => (
4  <Provider api={api}>
5    <YourRoutes />
6  </Provider>
7);

Querying data 

You can now use @gadgetinc/react's hooks for fetching models. Gadget provides various hooks for different kinds of queries: useFindOne, useMaybeFindOne, useFindMany, useFindFirst, useMaybeFindFirst, useFindBy, and useGet. These hooks mirror the underlying query methods found on the generated client for simple-blog-example.

useFindOne, useMaybeFindOne, useFindMany, useFindFirst, useMaybeFindFirst, and useGet take a manager from the API client as the first argument, whereas useFindBy takes a specific findByXYZ method on a manager. All of these methods also take an optional options argument. This is a combination of the options for the relevant query, such as select to choose specific fields, or filters and search for useFindMany, useFindFirst, and useMaybeFindFirst. This options object can also take any of the urql [useQuery] options (except query and variables).

The result of calling these hooks is a two element array, similar to the result of urql's useQuery hook. The first element is the result, composed of an error, fetching status, and the data itself. The second element is a function that you can call to run the query again. By default, urql will use its cache and reach out to the network only when it has been invalidated.

1import { useFindOne } from "@gadgetinc/react";
2import { api } from "shared/client";
3
4const BlogPosts = () => {
5  const [result, refresh] = useFindMany(api.posts, {
6    select: { id: true, title: true },
7  });
8
9  const { data, fetching, error } = result;
10  if (error) return <p>Error: {error.message}</p>;
11  if (fetching && !data) return <p>Fetching posts...</p>;
12  if (!data) return <p>Could not find any posts</p>;
13
14  return (
15    <ul>
16      {data.posts.map((post) => (
17        <li key={post.id}>{post.title}</li>
18      ))}
19    </ul>
20  );
21};

Running actions 

The Gadget React bindings provides three options for calling actions: useAction, useBulkAction, and useGlobalAction.

Similar to querying data, these hooks return a two element array. The first element contains all the same result information as queries, but the second element is a function to call the action. This function takes a variables object, along with an optional options argument.

1import { useAction } from "@gadgetinc/react";
2import { useRef } from "react";
3import { api } from "shared/client";
4
5const CreateComment = () => {
6  const commentInputRef = useRef(null);
7  const [result, createComment] = useAction(api.comments.create, {
8    select: { id: true },
9  });
10
11  const { fetching, result, error } = result;
12  return (
13    <form>
14      {error && <p>Error: {error.message}</p>}
15      {fetching && <p>Creating comment...</p>}
16      <div>
17        <label for="commentBody">Comment body:</label>
18        <input ref={commentInputRef} type="text" id="commentBody" />
19      </div>
20      <button
21        onClick={async (event) => {
22          event.preventDefault();
23          await createComment({ comment: { body: commentInputRef.current.value } });
24          commentInputRef.current.value = "";
25        }}
26      >
27        Create comment
28      </button>
29    </form>
30  );
31};