start-core/server-functions

Type-safe server functions in TanStack Start are created using the createServerFn API. You define a server function by specifying a method like GET or POST and attaching a handler, which can then be securely called from loaders or components.

Input validation for TanStack Start server functions is handled using the inputValidator API. It accepts either a custom validation function or a Zod schema to ensure the data passed to your server RPCs is securely typed and predictable.

You access request headers and server context in TanStack Start using server context utilities. Functions like getRequest, getRequestHeader, setResponseHeader, and setResponseStatus allow you to read and modify server context details within your RPCs.

Organize TanStack Start server function files using .functions.ts and .server.ts extensions. This file naming convention ensures clean separation of server logic from client code, keeping your server-side RPCs secure and maintainable.

Handle errors and redirects in TanStack Start server functions by throwing errors directly within the handler. You can also return redirect responses or notFound responses to control navigation and manage invalid states effectively.

Yes, TanStack Start server functions support both streaming and FormData handling. This allows you to manage progressive data delivery and file uploads securely within your type-safe server-side RPC architecture.