/**
* @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';
class Formatter {
static get CAPITAL_LETTERS() {
return /([A-Z])/g;
}
static get SUPPORTED_FORMATS() {
// Get the available formatters if they don't already exist.
if (!this._formatters) {
this._getFormatters();
}
// From the formatters we can establish a master list of supported format names.
if (!this._supportedFormatsNames) {
this._generateSupportedFormats();
}
return this._supportedFormatsNames;
}
static _getFormatters() {
this._formatters = {
accessibility: require('./accessibility'),
criticalRequestChains: require('./critical-request-chains'),
null: require('./null-formatter'),
userTimings: require('./user-timings')
};
}
static _generateSupportedFormats() {
const formatNames = Object.keys(this._formatters);
this._supportedFormatsNames = formatNames.reduce((prev, format) => {
// Reformulates names like criticalNetworkChains to CRITICAL_NETWORK_CHAINS so they appear
// like a bunch of constants.
const formatName = format.replace(Formatter.CAPITAL_LETTERS, '_$1').toUpperCase();
prev[formatName] = format;
return prev;
}, {});
}
static getByName(name) {
if (!this._formatters) {
this._getFormatters();
}
if (!this._formatters[name]) {
throw new Error(`Unknown formatter: ${name}`);
}
return this._formatters[name];
}
static getFormatter() {
throw new Error('Formatter must implement getPrettyFormatter()');
}
/**
* Optional function to get any Handlebars helpers this formatter expects to need.
*/
static getHelpers() {}
}
module.exports = Formatter;
|