server.ts

#!/usr/bin/env -S deno run --watch --check --allow-sys=hostname --allow-read --allow-net --allow-run=deno,dot --allow-env

import { httpTracer, trace } from "./deps.ts";
import { serveFont, servePublic, serveTemplatedHtml } from './lib/request-handling.ts';

// The different HTTP surfaces we expose
import * as DependenciesOf from './feat/dependencies-of/api.ts';
import * as Shields from './feat/shields/api.ts';
import * as RegistryKey from './feat/registry-key/api.ts';

let port = 5000;
try {
  port = parseInt(Deno.env.get('PORT') || port.toString());
} catch (err) {
  console.error(`WARN: failed to read $PORT due to ${err.name}`);
}

console.log('Setting up on', { port });
Deno.serve({
  port,
}, httpTracer(async request => {

  const resp = await handleReq(request);
  return resp ?? new Response('404 Not Found', {
    status: 404,
  });

}));

async function handleReq(req: Request): Promise<Response | undefined> {
  const url = new URL(req.url);

  { // feature: dependencies-of
    const match = url.pathname.match(/^\/dependencies-of\/(.*)$/);
    if (match && req.method === 'GET') {
      trace.getActiveSpan()?.setAttribute('http.route', 'dependencies-of');
      return await DependenciesOf.handleRequest(req, match[1], url.searchParams);
    }
  }

  { // feature: shields
    const match = url.pathname.match(/^\/shields\/([^\/]+)\/(.+)$/);
    if (match && req.method === 'GET') {
      trace.getActiveSpan()?.setAttribute('http.route', 'shield.'+match[1]);
      return await Shields.handleRequest(req, match[1], match[2]);
    }
  }

  { // feature: registry-key
    if (url.pathname === '/registry-key' && req.method === 'GET') {
      trace.getActiveSpan()?.setAttribute('http.route', 'registry-key');
      return await RegistryKey.handleRequest(req);
    }
  }

  if (url.pathname === '/') {
    trace.getActiveSpan()?.setAttribute('http.route', '/');
    return await serveTemplatedHtml(req, 'public/index.html');
  }

  if ([
    '/global.css',
    '/icon-deps.png',
    '/interactive-graph.js',
  ].includes(url.pathname)) {
    trace.getActiveSpan()?.setAttribute('http.route', 'public');
    return await servePublic(req, url.pathname);
  }

  if (url.pathname.startsWith('/fonts/') &&
      url.pathname.endsWith('.woff2')) {
    trace.getActiveSpan()?.setAttribute('http.route', 'fonts');
    return await serveFont(req, url.pathname.slice(6));
  }
}