React Query Read 📖

⚠️ This library is now obsolete, as similar functionality has been implemented in React Query itself.

Most convenient way to use React Query.

RQR is a tiny wrapper around React Query that adds a special read function. In contrast with the standard data field, the read function always returns already fetched data and cannot be undefined. Under the hood, it uses Suspense to achieve the best developer experience.

Installation

npm install react-query-read

Usage

With RQR you can turn code like this:

const {
  data: user,
  isError: isUserError,
  isPending: isUserPending,
} = useQuery({ queryKey: ["user"], queryFn: getUser });

const {
  data: posts,
  isError: isPostsError,
  isPending: isPostsPending,
} = useQuery({
  queryKey: ["posts", user?.id],
  queryFn: () => getPosts(user?.id),
  enabled: !!user?.id,
});

if (isUserPending || isPostsPending) {
  return <span>Loading...</span>;
}

if (isUserError || isPostsError) {
  return <span>Error</span>;
}

To something like this:

const { read: user } = useReadQuery({ queryKey: ["user"], queryFn: getUser });

const { read: posts } = useReadQuery({
  queryKey: ["posts", user().id],
  queryFn: () => getPosts(user().id),
});

It’s much easier to reason about since you don’t need to spend your mental energy writing code that checks if your data is undefined, loaded, or failed to load.

How it’s different from useSuspenseQuery?

Take for example this code:

const {data: user} = useSuspenseQuery({queryKey: ['user']);
const {data: settings} = useSuspenseQuery({queryKey: ['settings'});

In this case, these two queries will be executed in series. In other words, the second fetch will only be executed after the first one. This is a serious performance issue.

RQR mitigates this problem by separating the processes of query fetching and suspense.

const {read: readUser} = useReadQuery({queryKey: ['user']);
const {read: readSettings} = useReadQuery({queryKey: ['settings'});

const user = readUser();
const settings = readSettings();

In this example, two fetches will be executed immediately in parallel.

When you call the readUser function, React will pause rendering until the user is fetched.

Example

For a more complete example, see the example directory.