Route Parameters

A route can optionally export a parameters object, which is a Record of parameter names, paired with functions to safely decode them from the url string. If this object is exported the router will attempt to parse the params before calling the loader or action function, meaning for those functions to be called the url parameters must be valid.

export const parameters = {
  kind: (s: string) => {
    if (s !== "user" && s !== "group") throw new Response("invalid kind", { status: 400, statusText: "Bad Request" });
    return s;
  },
  id: Number
}

export async function loader({ params }: RouteContext<typeof parameters>) {
  // no type errors here, because they are of these types exactly
  const kind : "user" | "group" = params.kind;
  const id   : number           = params.number;
}

The route context also includes:

Key	Description
request	Request the original request object
url	The already parsed URL object of the request
cookie	The Cookies from the request, and set cookies will be added to the final response
headers	A header object that will be merged with the final response allowing early header setting
params	This object will be empty if no parameters object is exported