createTRPCQueryUtils
Similar to useUtils
, createTRPCQueryUtils
is a function that gives you access to helpers that let you manage the cached data of the queries you execute via @trpc/react-query
. These helpers are actually thin wrappers around @tanstack/react-query
's queryClient
methods. If you want more in-depth information about options and usage patterns for useUtils
helpers than what we provide here, we will link to their respective @tanstack/react-query
docs so you can refer to them accordingly.
The difference between useUtils
and createTRPCQueryUtils
is that useUtils
is a react hook that uses useQueryClient
under the hood. This means that it is able to work better within React Components.
The use case for createTRPCQueryUtils
is when you need to use the helpers outside of a React Component, for example in react-router's loaders.
You should avoid using createTRPCQueryUtils
in React Components. Instead, use useUtils
which is a React hook that implements useCallback
and useQueryClient
under the hood.
Usage
createTRPCQueryUtils
returns an object with all the available queries you have in your routers. You use it the same way as your trpc
client object. Once you reach a query, you'll have access to the query helpers. For example, let's say you have a post
router with an all
query:
Now in our component, when we navigate the object createTRPCQueryUtils
gives us and reach the post.all
query, we'll get access to our query helpers!
MyPage.tsxtsx
import { QueryClient } from '@tanstack/react-query';import { createTRPCQueryUtils, createTRPCReact } from '@trpc/react-query';import { useLoaderData } from 'react-router-dom';import type { AppRouter } from './server';const trpc = createTRPCReact<AppRouter>();const trpcClient = trpc.createClient({ links: [] );const queryClient = new QueryClient();const clientUtils = createTRPCQueryUtils({ queryClient, client: trpcClient });// This is a react-router loaderexport async function loader() {const allPostsData = await clientUtils.post.all.ensureData(); // Fetches data if it doesn't exist in the cachereturn {allPostsData,};}// This is a react componentexport function Component() {const loaderData = useLoaderData() as Awaited<ReturnType<typeof loader>>;const allPostQuery = trpc.post.all.useQuery({initialData: loaderData.allPostsData, // Uses the data from the loader});return (<div>{allPostQuery.data.posts.map((post) => (<div key={post.id}>{post.title}</div>))}</div>);}
MyPage.tsxtsx
import { QueryClient } from '@tanstack/react-query';import { createTRPCQueryUtils, createTRPCReact } from '@trpc/react-query';import { useLoaderData } from 'react-router-dom';import type { AppRouter } from './server';const trpc = createTRPCReact<AppRouter>();const trpcClient = trpc.createClient({ links: [] );const queryClient = new QueryClient();const clientUtils = createTRPCQueryUtils({ queryClient, client: trpcClient });// This is a react-router loaderexport async function loader() {const allPostsData = await clientUtils.post.all.ensureData(); // Fetches data if it doesn't exist in the cachereturn {allPostsData,};}// This is a react componentexport function Component() {const loaderData = useLoaderData() as Awaited<ReturnType<typeof loader>>;const allPostQuery = trpc.post.all.useQuery({initialData: loaderData.allPostsData, // Uses the data from the loader});return (<div>{allPostQuery.data.posts.map((post) => (<div key={post.id}>{post.title}</div>))}</div>);}
If you were using Remix Run or SSR you wouldn't re-use the same queryClient
for every request. Instead, you would create a new queryClient
for every request so that there's no cross-request data leakage.
Helpers
Much like useUtils
, createTRPCQueryUtils
gives you access to same set of helpers. The only difference is that you need to pass in the queryClient
and client
objects.
You can see them on the useUtils page.