Add new prerender-user-profile-page Vercel prerender function

vercel-functions/prerender-user-profile-page.func/.gitignore

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+/node_modules
+/dist

vercel-functions/prerender-user-profile-page.func/.vc-config.json

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+{
+  "handler": "index.js",
+  "runtime": "nodejs22.x",
+  "memory": 3009,
+  "maxDuration": 15,
+  "launcherType": "Nodejs",
+  "shouldAddHelpers": true,
+  "shouldAddSourcemapSupport": true
+}

vercel-functions/prerender-user-profile-page.func/index.js

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+import FastBoot from 'fastboot';
+import { replaceAllMetaTags } from './replace-meta-tag.js';
+
+export default async function (request, response) {
+  const { username } = request.query;
+
+  // Check if username query parameter is provided
+  if (!username) {
+    console.error('Missing "username" query parameter');
+    response.redirect('/404');
+
+    return;
+  }
+
+  // Initialize a FastBoot instance
+  const app = new FastBoot({
+    distPath: 'dist',
+    resilient: false,
+
+    // Customize the sandbox globals
+    buildSandboxGlobals(defaultGlobals) {
+      return Object.assign({}, defaultGlobals, {
+        AbortController,
+      });
+    },
+
+    maxSandboxQueueSize: 1,
+  });
+
+  // Visit the user profile page
+  const result = await app.visit(`/users/${username}`);
+  const statusCode = result._fastbootInfo.response.statusCode;
+
+  // Redirect to 404 page if the status code is not 200
+  if (statusCode !== 200) {
+    console.warn('Error parsing FastBoot response, statusCode was:', statusCode);
+    response.redirect('/404');
+
+    return;
+  }
+
+  // Get the HTML content of the FastBoot response
+  const html = await result['html'](); // Weird VSCode syntax highlighting issue if written as result.html()
+
+  // Define meta tag values
+  const pageTitle = `${username}'s CodeCrafters Profile`;
+  const pageImageUrl = `https://og.codecrafters.io/api/user_profile/${username}`; // TODO: Read `metaTagUserProfilePictureBaseURL` from page config
+  const pageDescription = `View ${username}'s profile on CodeCrafters`;
+
+  // Replace meta tags in the HTML content
+  const responseText = replaceAllMetaTags(html, pageTitle, pageDescription, pageImageUrl);
+
+  // Send the modified HTML content as the response
+  response.send(responseText);
+}