Authentication in Reno with a higher-order route handler

reno-auth-hof.ts

import {
  RouteHandler,
  AugmentedRequest,
  textResponse,
  createRouter,
  createRouteMap,
} from "https://deno.land/x/[email protected]/reno/mod.ts";

import { Status } from "https://deno.land/[email protected]/http/mod.ts";

function hasValidSession(req: AugmentedRequest) {
  // Verify JWT, lookup session in database etc...
}

function unauthorised() {
  return textResponse("Unauthorised", {}, Status.Unauthorized);
}

function withAuth(handler: RouteHandler): RouteHandler {
  return (req) => hasValidSession(req) ? handler(req) : unauthorised();
}

function profileRoute() {
  // Route handler for user profile
}

// Usage:
// Protect an individual route
const protectedProfile = withAuth(profileRoute);

// Protect an entire router
const userRouter = withAuth(createRouter(createRouteMap([
  ["/profile", profileRoute],
])));