add lighthouse CI checks for core features

Signed-off-by: Emma Indal <emma.indahl@gmail.com>

.github/workflows/verify_accessibility_core.yml

@@ -0,0 +1,29 @@
+name: Verify Accessibility Core features
+on:
+  pull_request:
+    branches: [master]
+    paths:
+      - 'plugins/catalog/**'
+      - 'plugins/techdocs/**'
+      - 'plugins/scaffolder/**'
+      - 'plugins/search/**'
+
+jobs:
+  lhci:
+    name: Lighthouse
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - name: Use Node.js 16.x
+        uses: actions/setup-node@v3
+        with:
+          node-version: 16.x
+      - name: install dependencies
+        run: |
+          yarn install
+      - name: run Lighthouse CI
+        run: |
+          npm install -g @lhci/cli@0.11.x
+          lhci autorun
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

.gitignore

@@ -152,3 +152,7 @@ tsconfig.tmp.json
 
 # vscode database functionality support files
 *.session.sql
+
+# Lighthouse CI Reports
+**/.lighthouseci/*
+!**/.lighthouseci/scripts

.lighthouseci/scripts/guest-auth.js

@@ -0,0 +1,11 @@
+'use strict';
+
+module.exports = async (browser, context) => {
+  // launch browser for LHCI
+  const page = await browser.newPage();
+  await page.goto('http://localhost:3000');
+  await page.evaluate(() => {
+    localStorage.setItem('@backstage/core:SignInPage:provider', 'guest');
+  });
+  await page.goto('http://localhost:3000');
+};

lighthouserc.js

@@ -0,0 +1,60 @@
+/*
+ * Copyright 2023 The Backstage Authors
+ *
+ * Licensed 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 CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+module.exports = {
+  ci: {
+    collect: {
+      url: [
+        /** Software Catalog */
+        'http://localhost:3000/catalog',
+        'http://localhost:3000/catalog-import',
+        'http://localhost:3000/catalog/default/component/backstage',
+        /** TechDocs */
+        'http://localhost:3000/docs',
+        'http://localhost:3000/docs/default/component/backstage',
+        /** Software Templates */
+        'http://localhost:3000/create',
+        'http://localhost:3000/create/tasks',
+        'http://localhost:3000/create/actions',
+        'http://localhost:3000/create/edit',
+        'http://localhost:3000/create/templates/default/react-ssr-template',
+        /** Search */
+        'http://localhost:3000/search',
+      ],
+      settings: {
+        onlyCategories: ['accessibility'],
+        // need to disable storage reset because of auth
+        disableStorageReset: true,
+        output: ['html', 'json'],
+        outputPath: './.lighthouseci/reports',
+        preset: 'desktop',
+      },
+      startServerCommand: 'yarn dev',
+      startServerReadyTimeout: 600000,
+      numberOfRuns: 1,
+      puppeteerScript: './.lighthouseci/scripts/guest-auth.js',
+      startServerReadyPattern: 'Listening on :7007',
+    },
+    assert: {
+      assertions: {
+        'categories:performance': 'off',
+        'categories:pwa': 'off',
+        'categories:best-practices': 'off',
+        'categories:seo': 'off',
+        'categories:accessibility': ['error', { minScore: 0.85 }],
+      },
+    },
+  },
+};