feat: introduce canonical audit

assessment/canonical.js

@@ -0,0 +1,90 @@
+/*
+ * Copyright 2024 Adobe. All rights reserved.
+ * This file is licensed to you under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License. You may obtain a copy
+ * of the License at http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under
+ * the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR REPRESENTATIONS
+ * OF ANY KIND, either express or implied. See the License for the specific language
+ * governing permissions and limitations under the License.
+ */
+import { JSDOM } from 'jsdom';
+import { createAssessment } from './assessment-lib.js';
+import { fetchSitemapsFromBaseUrl } from './sitemap.js';
+
+const TRACKING_PARAM = '?utm';
+const userSiteUrl = process.argv[2];
+
+const checkForCanonical = async (url, assessment) => {
+  try {
+    const response = await fetch(url);
+    const contentType = response.headers.get('content-type');
+    if (response.ok && contentType.includes('text/html')) {
+      const htmlContent = await response.text();
+      const dom = new JSDOM(htmlContent);
+
+      // should be in the head
+      const { head } = dom.window.document;
+      const canonicalLink = head.querySelector('link[rel="canonical"]')?.href;
+
+      // check if canonical link exists
+      if (canonicalLink) {
+        assessment.addColumn({
+          url,
+          canonicalExists: true,
+          response: response.status,
+          presentInSiteMap: url === canonicalLink,
+          www: url.startsWith('https://www.'),
+          hasTrailingSlash: url.endsWith('/'),
+          hasHtmlExtension: url.endsWith('.html'),
+          hasTrackingParams: url.includes(TRACKING_PARAM),
+        });
+      } else {
+        assessment.addColumn({
+          url,
+          error: 'No canonical link found',
+        });
+      }
+    } else {
+      assessment.addColumn({
+        url,
+        response: response.status,
+        error: `URL ${url} is not an HTML page`,
+      });
+    }
+  } catch (error) {
+    assessment.addColumn({
+      url,
+      error: `Error fetching URL ${url}: ${error.message}`,
+    });
+  }
+};
+
+const canonicalAudit = async (siteUrl, assessment) => {
+  // TODO: fetch sitemap url from file if already exists
+  const sitemaps = await fetchSitemapsFromBaseUrl(siteUrl);
+  return Promise.all(sitemaps.map((sitemap) => {
+    if (sitemap.page) {
+      return checkForCanonical(sitemap.page, assessment);
+    }
+  }));
+};
+
+(async () => {
+  const assessment = await createAssessment(userSiteUrl, 'Canonical');
+  assessment.setRowHeadersAndDefaults({
+    url: '',
+    canonicalExists: false,
+    response: '',
+    presentInSiteMap: false,
+    www: undefined,
+    hasTrailingSlash: undefined,
+    hasHtmlExtension: undefined,
+    hasTrackingParams: undefined,
+    error: '',
+    warning: '',
+  });
+  await canonicalAudit(userSiteUrl, assessment);
+  assessment.end();
+})();

assessment/sitemap.js

@@ -110,6 +110,21 @@ async function fetchSitemapsFromRobots(siteUrl) {
   return fetchSitemapsFromSource(sitemapSources);
 }
 
+export async function fetchSitemapsFromBaseUrl(url) {
+  let sitemaps = await fetchSitemapsFromRobots(userSiteUrl);
+  if (!sitemaps.length) {
+    sitemaps = await fetchSitemapsFromSource([
+      { url: new URL('sitemap.xml', url).toString(), source: 'Default path /sitemap.xml' },
+    ]);
+    if (!sitemaps.length) {
+      sitemaps = await fetchSitemapsFromSource([
+        { url: new URL('sitemap_index.xml', url).toString(), source: 'Default path /sitemap_index.xml' },
+      ]);
+    }
+  }
+  return sitemaps;
+};
+
 (async () => {
   const assessment = await createAssessment(userSiteUrl, 'Sitemap');
   assessment.setRowHeadersAndDefaults({
@@ -120,17 +135,7 @@ async function fetchSitemapsFromRobots(siteUrl) {
     warning: '',
   });
 
-  let sitemaps = await fetchSitemapsFromRobots(userSiteUrl);
-  if (!sitemaps.length) {
-    sitemaps = await fetchSitemapsFromSource([
-      { url: new URL('sitemap.xml', userSiteUrl).toString(), source: 'Default path /sitemap.xml' },
-    ]);
-    if (!sitemaps.length) {
-      sitemaps = await fetchSitemapsFromSource([
-        { url: new URL('sitemap_index.xml', userSiteUrl).toString(), source: 'Default path /sitemap_index.xml' },
-      ]);
-    }
-  }
+  const sitemaps = await fetchSitemapsFromBaseUrl(userSiteUrl);
 
   // Assessment for sitemaps
   sitemaps.forEach(async (sitemap) => {