index.js

/**
 * @license
 * Copyright 2016 Google Inc. All rights reserved.
 *
 * 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.
 */

'use strict';

const Runner = require('./runner');
const log = require('./lib/log.js');
const ChromeProtocol = require('./gather/connections/cri.js');
const Config = require('./config/config');

/**
 * The relationship between these root modules:
 *
 *   index.js  - the require('lighthouse') hook for Node modules (including the CLI)
 *
 *   runner.js - marshalls the actions that must be taken (Gather / Audit / Aggregate)
 *               config file is used to determine which of these actions are needed
 *
 *   lighthouse-cli \
 *                   -- index.js  \
 *                                 ----- runner.js ----> [Gather / Audit / Aggregate]
 *           lighthouse-extension /
 *
 */

module.exports = function(url, flags = {}, configJSON) {
  const startTime = Date.now();
  return Promise.resolve().then(_ => {
    if (!url) {
      throw new Error('Lighthouse requires a URL');
    }

    // set logging preferences, assume quiet
    flags.logLevel = flags.logLevel || 'error';
    log.setLevel(flags.logLevel);

    // Use ConfigParser to generate a valid config file
    const config = new Config(configJSON, flags.configPath);

    const connection = new ChromeProtocol(flags.port);

    // kick off a lighthouse run
    return Runner.run(connection, {url, flags, config})
      .then(lighthouseResults => {
        // Annotate with time to run lighthouse.
        const endTime = Date.now();
        lighthouseResults.timing = lighthouseResults.timing || {};
        lighthouseResults.timing.total = endTime - startTime;

        return lighthouseResults;
      });
  });
};

module.exports.getAuditList = Runner.getAuditList;
module.exports.traceCategories = require('./gather/driver').traceCategories;
module.exports.Audit = require('./audits/audit');
module.exports.Gatherer = require('./gather/gatherers/gatherer');