Fresh Redis Session Middleware

_middleware.js

// routes/_middleware.js
import { cyan, green, yellow } from "$std/fmt/colors.ts";
import { getCookies, setCookie } from "$std/http/cookie.ts";
import { config } from "$std/dotenv/mod.ts";
import * as redis from "redis";

// import_map.json
// "@/": "./",
// "$std/": "https://deno.land/[email protected]/",
// "redis": "https://deno.land/x/[email protected]/mod.ts",

// Load dotenv over Deno.env
const env = Object.assign(Deno.env.toObject(), await config());
const { REDIS_PASS, REDIS_HOST, REDIS_PORT, API_URL, DENO_ENV } = env;
const COOKIE_NAME = "uuid";
const store = await redis.connect({
  password: REDIS_PASS,
  hostname: REDIS_HOST,
  port: REDIS_PORT,
});

// Session Tracker
const createSession = async () => {
  const session = {
    cart: [],
  };
  session[COOKIE_NAME] = crypto.randomUUID()
  await store.set(session[COOKIE_NAME], JSON.stringify(session));
  await store.expire(session[COOKIE_NAME], 7 * 24 * 60 * 60);
  return session;
};

const setupSession = async (req, ctx) => {
  const cookies = getCookies(req.headers);
  let tracker_id = cookies[COOKIE_NAME];
  if (tracker_id) {
    const session = await store.get(tracker_id);
    if (session) {
      ctx.state = JSON.parse(session);
    } else {
      tracker_id = false;
      ctx.state = await createSession();
    }
  } else {
    ctx.state = await createSession();
  }
  if (!tracker_id) {
    const resp = await ctx.next();
    setCookie(resp.headers, { name: COOKIE_NAME, value: ctx.state[COOKIE_NAME] });
    return resp;
  } else {
    return await ctx.next();
  }
};

export async function handler(req, ctx) {
  // Logging
  const start = Date.now();
  const { pathname } = new URL(req.url);
  const withSession = [
    "/",
    "/pages",
    "/with",
    "/sessions",
    "/here",
    "/middleware",
    "/runs/always",
  ];
  let resp;
  if (
    withSession.includes(pathname) ||
    pathname.startsWith("/api/") ||
    pathname.startsWith("/scans/")
  ) {
    ctx.API_URL = API_URL;
    ctx.DENO_ENV = DENO_ENV;
    ctx.store = store;
    resp = await setupSession(req, ctx);
  } else {
    resp = await ctx.next();
  }
  // Timing stuff - from oak
  const ms = Date.now() - start;
  resp.headers.set("X-Response-Time", `${ms}ms`);
  // console.log( ms, req )
  console.log(
    `${green(req.method)} ${cyan(pathname)} - ${yellow(String(ms) + "ms")}`,
  );
  return resp;
}