Local Link
localLink
is a terminating link that allows you to make tRPC procedure calls directly in your application without going through HTTP.
info
We have prefixed this as experimental_
as it's a new API! Read more.
Usage
tsx
import { createTRPCClient, experimental_localLink } from '@trpc/client';import type { AppRouter } from '../server';const client = createTRPCClient<AppRouter>({links: [experimental_localLink({router: appRouter,createContext: async () => {// Create your context herereturn {};},onError: (opts) => {// Log errors here, similarly to how you would in an API routeconsole.error('Error:', opts.error);},}),],});
tsx
import { createTRPCClient, experimental_localLink } from '@trpc/client';import type { AppRouter } from '../server';const client = createTRPCClient<AppRouter>({links: [experimental_localLink({router: appRouter,createContext: async () => {// Create your context herereturn {};},onError: (opts) => {// Log errors here, similarly to how you would in an API routeconsole.error('Error:', opts.error);},}),],});
Features
- Direct procedure calls without HTTP overhead
- Full support for queries, mutations, and subscriptions
- Automatic error handling and transformation
- Support for abort signals
- Type-safe context creation
Options
The localLink
accepts the following options:
ts
type LocalLinkOptions<TRouter extends AnyRouter> = {router: TRouter;createContext: () => Promise<inferRouterContext<TRouter>>;onError?: (opts: ErrorHandlerOptions<inferRouterContext<TRouter>>) => void;} & TransformerOptions<inferClientTypes<TRouter>>;
ts
type LocalLinkOptions<TRouter extends AnyRouter> = {router: TRouter;createContext: () => Promise<inferRouterContext<TRouter>>;onError?: (opts: ErrorHandlerOptions<inferRouterContext<TRouter>>) => void;} & TransformerOptions<inferClientTypes<TRouter>>;
router
The tRPC router instance to use for procedure calls.
createContext
A function that creates the context for each procedure call. This is called for each request and should return a promise that resolves to the context object.
onError
An optional error handler that is called when an error occurs during a procedure call. It receives the error, operation type, path, input, and context.
transformer
Optional input/output transformers for serialization/deserialization of data.
Notes
- It's recommended to use this link in scenarios where you need direct procedure calls without HTTP
- For most client-side applications, you should use the
httpLink
or other HTTP-based links instead - The link supports all tRPC features including queries, mutations, and subscriptions
- Error handling and transformation are handled automatically, just like with HTTP-based links