Add custom script for checking lit.dev redirects

Author: aomarks

.github/workflows/build.yml

@@ -22,6 +22,9 @@ jobs:
       - name: Build
         run: npm run build
 
+      - name: Check for broken redirects
+        run: npm run test:links:redirects
+
       - name: Check for broken links (internal)
         run: npm run test:links:internal
 

package.json

@@ -11,7 +11,8 @@
     "format": "prettier \"**/*.{ts,js,json,html,css,md}\" --write",
     "nuke": "rm -rf node_modules package-lock.json packages/*/node_modules packages/*/package-lock.json && npm install && npx lerna bootstrap",
     "test": "npm run test:links",
-    "test:links": "npm run test:links:internal && npm run test:links:external",
+    "test:links": "npm run test:links:redirects && npm run test:links:internal && npm run test:links:external",
+    "test:links:redirects": "node packages/lit-dev-tools-esm/lib/check-redirects.js",
     "test:links:internal": "run-p -r start check-links:internal",
     "test:links:external": "run-p -r start check-links:external",
     "check-links:internal": "wait-on tcp:8080 && blc http://localhost:8080 --recursive --exclude-external --ordered",

packages/lit-dev-tools-esm/package-lock.json

@@ -0,0 +1,124 @@
+/**
+ * @license
+ * Copyright 2021 Google LLC
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+import * as pathLib from 'path';
+import * as fs from 'fs/promises';
+import ansi from 'ansi-escape-sequences';
+import fetch from 'node-fetch';
+import {pageRedirects} from 'lit-dev-server/redirects.js';
+import {fileURLToPath} from 'url';
+
+const __filename = fileURLToPath(import.meta.url);
+const __dirname = pathLib.dirname(__filename);
+
+const {red, green, yellow, bold, reset} = ansi.style;
+
+const OK = Symbol();
+type ErrorMessage = string;
+
+const isUrl = (str: string) => {
+  try {
+    new URL(str);
+    return true;
+  } catch {
+    return false;
+  }
+};
+
+const trimTrailingSlash = (str: string) =>
+  str.endsWith('/') ? str.slice(0, str.length - 1) : str;
+
+const siteOutputDir = pathLib.resolve(
+  __dirname,
+  '../',
+  '../',
+  'lit-dev-content',
+  '_site'
+);
+
+const checkRedirect = async (
+  redirect: string
+): Promise<ErrorMessage | typeof OK> => {
+  if (isUrl(redirect)) {
+    // Remote URLs.
+    let res;
+    try {
+      res = await fetch(redirect);
+    } catch (e) {
+      return `Fetch error: ${(e as Error).message}`;
+    }
+    if (res.status !== 200) {
+      return `HTTP ${res.status} error`;
+    }
+  } else {
+    // Local paths. A bit hacky, but since we know how Eleventy works, we don't
+    // need to actually run the server, we can just look directly in the built
+    // HTML output directory.
+    const {pathname, hash} = new URL(redirect, 'http://lit.dev');
+    const diskPath = pathLib.relative(
+      process.cwd(),
+      pathLib.join(siteOutputDir, trimTrailingSlash(pathname), 'index.html')
+    );
+    let data;
+    try {
+      data = await fs.readFile(diskPath, {encoding: 'utf8'});
+    } catch {
+      return `Could not find file matching path ${pathname}
+Searched for file ${diskPath}`;
+    }
+    if (hash) {
+      // Another hack. Just do a regexp search for e.g. id="somesection" instead
+      // of DOM parsing. Should be good enough, especially given how regular our
+      // Markdown generated HTML is.
+      const idAttrRegExp = new RegExp(`\\sid=["']?${hash.slice(1)}["']?[\\s>]`);
+      if (data.match(idAttrRegExp) === null) {
+        return `Could not find section matching hash ${hash}.
+Searched in file ${diskPath}`;
+      }
+    }
+  }
+  return OK;
+};
+
+const checkAllRedirects = async () => {
+  console.log('==========================');
+  console.log('Checking lit.dev redirects');
+  console.log('==========================');
+  console.log();
+
+  let fail = false;
+  const promises = [];
+  for (const [from, to] of pageRedirects) {
+    promises.push(
+      (async () => {
+        const result = await checkRedirect(to);
+        if (result === OK) {
+          console.log(`${bold + green}OK${reset} ${from} -> ${to}`);
+        } else {
+          console.log();
+          console.log(
+            `${bold + red}BROKEN REDIRECT${reset} ${from} -> ${
+              yellow + to + reset
+            }`
+          );
+          console.log(result);
+          console.log();
+          fail = true;
+        }
+      })()
+    );
+  }
+  await Promise.all(promises);
+  console.log();
+  if (fail) {
+    console.log('Redirects were broken!');
+    process.exit(1);
+  } else {
+    console.error('All redirects OK!');
+  }
+};
+
+checkAllRedirects();

packages/lit-dev-tools-esm/src/check-redirects.ts

@@ -12,8 +12,10 @@
     "test": "npm run build && uvu ./lib \".spec.js$\""
   },
   "dependencies": {
+    "@types/jsdom": "^16.2.13",
     "@types/markdown-it": "^12.0.1",
     "@types/source-map": "^0.5.7",
+    "@types/strip-comments": "^2.0.1",
     "@web/dev-server": "^0.1.6",
     "@web/dev-server-core": "^0.3.5",
     "fast-glob": "^3.2.5",
@@ -27,8 +29,6 @@
     "strip-comments": "^2.0.1",
     "striptags": "^3.2.0",
     "typedoc": "^0.20.30",
-    "@types/jsdom": "^16.2.13",
-    "@types/strip-comments": "^2.0.1",
     "uvu": "^0.5.1"
   }
 }