Merge pull request #38 from anil-groupon/add-lh-api

feat: Add supporting APIs for lighthouse

lib/browser/lighthouse.js

@@ -0,0 +1,168 @@
+/*
+ * Copyright (c) 2015, Groupon, Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * Neither the name of GROUPON nor the names of its contributors may be
+ * used to endorse or promote products derived from this software without
+ * specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+ * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+ * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
+ * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+'use strict';
+
+const assert = require('assertive');
+const isEmpty = require('lodash/isEmpty');
+
+function getTotalScore(success, failure) {
+  const successCount = Object.keys(success).length;
+  const errorCount = Object.keys(failure).length;
+
+  return (successCount * 100) / (successCount + errorCount);
+}
+
+const lhConfig = {
+  passes: [
+    {
+      passName: 'accessibilityPass',
+      gatherers: ['accessibility'],
+    },
+  ],
+  audits: [
+    'accessibility/accesskeys',
+    'accessibility/aria-allowed-attr',
+    'accessibility/aria-required-attr',
+    'accessibility/aria-required-children',
+    'accessibility/aria-required-parent',
+    'accessibility/aria-roles',
+    'accessibility/aria-valid-attr-value',
+    'accessibility/aria-valid-attr',
+    'accessibility/audio-caption',
+    'accessibility/button-name',
+    'accessibility/bypass',
+    'accessibility/color-contrast',
+    'accessibility/definition-list',
+    'accessibility/dlitem',
+    'accessibility/document-title',
+    'accessibility/duplicate-id',
+    'accessibility/frame-title',
+    'accessibility/html-has-lang',
+    'accessibility/html-lang-valid',
+    'accessibility/image-alt',
+    'accessibility/input-image-alt',
+    'accessibility/label',
+    'accessibility/layout-table',
+    'accessibility/link-name',
+    'accessibility/list',
+    'accessibility/listitem',
+    'accessibility/meta-refresh',
+    'accessibility/meta-viewport',
+    'accessibility/object-alt',
+    'accessibility/tabindex',
+    'accessibility/td-headers-attr',
+    'accessibility/th-has-data-cells',
+    'accessibility/valid-lang',
+    'accessibility/video-caption',
+    'accessibility/video-description',
+  ],
+};
+
+const parseLhResult = function(results) {
+  if (!results || !results.lhr || !results.lhr.audits) {
+    throw new Error(`Error fetching lighthouse audit results`);
+  }
+
+  const audits = results.lhr.audits;
+
+  const errorsObj = {};
+  const notApplicableObj = {};
+  const successObj = {};
+
+  for (const key in audits) {
+    const audit = audits[key];
+    const description = audit.description;
+    const details = audit.details;
+    const id = audit.id;
+    const score = audit.score;
+    const scoreDisplayMode = audit.scoreDisplayMode;
+
+    const auditInfo = { description, details };
+
+    if (score) {
+      successObj[id] = auditInfo;
+    } else if (scoreDisplayMode === 'not-applicable') {
+      notApplicableObj[id] = auditInfo;
+    } else if (scoreDisplayMode !== 'manual') {
+      const snippets = [];
+      if (!isEmpty(details.items)) {
+        details.items.forEach(item => snippets.push(item.node.snippet || ''));
+      }
+
+      errorsObj[id] = { description, snippets };
+    }
+  }
+
+  const score = getTotalScore(successObj, errorsObj);
+
+  return {
+    audits,
+    score,
+    isSuccess(cutoff) {
+      return score >= cutoff;
+    },
+    success(type) {
+      return type ? successObj[type] : successObj;
+    },
+    errors(type) {
+      return type ? errorsObj[type] : errorsObj;
+    },
+    errorString() {
+      const errorList = [];
+
+      for (const id in errorsObj) {
+        const description = errorsObj[id].description;
+        const snippets = errorsObj[id].snippets;
+        errorList.push(`${description}:\n\t${snippets.join('\n\t')}`);
+      }
+
+      return errorList.join('\n\n');
+    },
+  };
+};
+
+exports.assertLighthouseScore = function assertLighthouseScore(
+  score,
+  flags,
+  config
+) {
+  const assertScore = function aScore(res) {
+    assert.expect(parseLhResult(res).isSuccess(score));
+  };
+
+  return this.getLighthouseData(flags, config || lhConfig).then(assertScore);
+};
+
+exports.runLighthouseAudit = function runLighthouseAudit(flags, config) {
+  return this.getLighthouseData(flags, config || lhConfig).then(parseLhResult);
+};

lib/testium-driver-wd.js

@@ -65,6 +65,7 @@ const defaultMethods = [
   require('./browser/navigation'),
   require('./browser/page'),
   require('./browser/window'),
+  require('./browser/lighthouse'),
   /* eslint-enable */
 ];