atcities.dev / server / src / index.ts

import root from "./routes/root.ts";
import user from "./routes/user.ts";
import backfill from "./backfill/index.ts";
import { clearCookies, PORT, ROOT_DOMAIN, SUBDOMAIN_REGEX } from "./utils.ts";

const db = await backfill;

Deno.serve({ port: PORT, hostname: ROOT_DOMAIN }, async (req) => {
  const reqUrl = new URL(req.url);
  const subdomain = reqUrl.hostname.match(SUBDOMAIN_REGEX)?.at(0)?.split(".");

  // redirect ROOT_DOMAIN => www.ROOT_DOMAIN
  if (!subdomain) {
    const redirUrl = new URL(reqUrl.toString());
    redirUrl.host = "www." + redirUrl.host;
    return new Response(`Redirecting to ${redirUrl.toString()}`, {
      status: 308,
      headers: {
        Location: redirUrl.toString(),
      },
    });
  }

  if (subdomain.length === 1 && subdomain[0] === "www") return root(req);

  // did:plc example: `sjkdgfjk.did-plc.ROOT_DOMAIN`
  // did:web example: `vielle.dev.did-web.ROOT_DOMAIN
  // last segment must be did-plc or did-web
  const isDidSubdomain = !!subdomain.at(-1)?.match(/^did-(web|plc)+$/gm);
  // ex: vielle.dev.ROOT_DOMAIN
  // cannot contain hyphen in top level domain
  const isHandleSubdomain = !isDidSubdomain && subdomain.length > 1;

  if (isDidSubdomain || isHandleSubdomain) {
    const res: Response = await user(
      db,
      req,
      isDidSubdomain
        ? {
            did: `did:${subdomain.at(-1) === "did-plc" ? "plc" : "web"}:${subdomain
              .slice(0, -1)
              .join(".")}`,
          }
        : {
            handle: subdomain.join(".") as `${string}.${string}`,
          }
    );
    return new Response(res.body, {
      ...res,
      headers: {
        ...res.headers,
        ...clearCookies(req),
      },
    });
  }

  return new Response(
    `Could not resolve domain "${subdomain.join(".")}.${ROOT_DOMAIN}"`,
    {
      status: 404,
    }
  );
});