Add canonical / alternate links for mozilla collections (and only those) (#13129)

* Add canonical / alternate links for mozilla collections (and only those)

Non-mozilla collections are disallowed in robots.txt

Author: diox

src/amo/pages/Collection/index.js

@@ -1,4 +1,5 @@
 /* @flow */
+import config from 'config';
 import deepEqual from 'deep-eql';
 import invariant from 'invariant';
 import * as React from 'react';
@@ -11,6 +12,7 @@ import Button from 'amo/components/Button';
 import CollectionAddAddon from 'amo/components/CollectionAddAddon';
 import CollectionControls from 'amo/components/CollectionControls';
 import CollectionDetailsCard from 'amo/components/CollectionDetailsCard';
+import HeadLinks from 'amo/components/HeadLinks';
 import NotFoundPage from 'amo/pages/ErrorPages/NotFoundPage';
 import Link from 'amo/components/Link';
 import Page from 'amo/components/Page';
@@ -586,6 +588,13 @@ export class CollectionBase extends React.Component<InternalProps> {
               <meta name="description" content={this.getPageDescription()} />
             </Helmet>
           )}
+          {
+            /* Only include canonical/alternate links if this is a mozilla collection */
+            collection &&
+              collection.authorId === config.get('mozillaUserId') && (
+                <HeadLinks />
+              )
+          }
 
           {errorHandler.renderErrorIfPresent()}
 

tests/unit/amo/pages/TestCollection.js

@@ -19,6 +19,7 @@ import {
   INSTALL_SOURCE_SUGGESTIONS,
   MOZILLA_COLLECTIONS_EDIT,
 } from 'amo/constants';
+import { hrefLangs } from 'amo/languages';
 import {
   FETCH_CURRENT_COLLECTION,
   FETCH_CURRENT_COLLECTION_PAGE,
@@ -63,6 +64,7 @@ import {
   fakeI18n,
   fakePreview,
   getElement,
+  getElements,
   getMockConfig,
   renderPage as defaultRender,
   screen,
@@ -1147,6 +1149,49 @@ describe(__filename, () => {
     );
   });
 
+  it('renders canonical and alternate links for mozilla collections', async () => {
+    renderWithCollection({
+      detailProps: { authorId: mozillaUserId },
+      userId: mozillaUserId,
+    });
+
+    const getExpectedURL = (locale, app) => {
+      return `${config.get(
+        'baseURL',
+      )}/${locale}/${app}/collections/${mozillaUserId}/${defaultSlug}/`;
+    };
+
+    await waitFor(() =>
+      expect(getElement('link[rel="canonical"]')).toHaveAttribute(
+        'href',
+        getExpectedURL('en-US', 'firefox'),
+      ),
+    );
+
+    await waitFor(() =>
+      expect(getElement('link[rel="alternate"]')).toBeInTheDocument(),
+    );
+
+    expect(getElements('link[rel="alternate"]')).toHaveLength(hrefLangs.length);
+
+    const hrefLangsMap = config.get('hrefLangsMap');
+    hrefLangs.forEach((hrefLang) => {
+      const locale = hrefLangsMap[hrefLang] || hrefLang;
+      expect(
+        getElement(`link[rel="alternate"][hreflang="${hrefLang}"]`),
+      ).toHaveAttribute('href', getExpectedURL(locale, 'firefox'));
+    });
+  });
+
+  it('does not render canonical and alternate links for non-mozilla collections', async () => {
+    renderWithCollection();
+
+    await waitFor(() =>
+      expect(getElement('meta[name="description"]')).toBeInTheDocument(),
+    );
+    expect(getElements('link[rel="canonical"]')).toHaveLength(0);
+  });
+
   describe('errorHandler - extractId', () => {
     it('returns a unique ID based on params', () => {
       const props = {