puppeteer-core
Version:
A high-level API to control headless Chrome over the DevTools Protocol
330 lines • 12.8 kB
JavaScript
/**
* Copyright 2017 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.
*/
import { assert } from './assert.js';
import { helper, debugError } from './helper.js';
import { EVALUATION_SCRIPT_URL } from './ExecutionContext.js';
/**
* The Coverage class provides methods to gathers information about parts of
* JavaScript and CSS that were used by the page.
*
* @remarks
* To output coverage in a form consumable by {@link https://github.com/istanbuljs | Istanbul},
* see {@link https://github.com/istanbuljs/puppeteer-to-istanbul | puppeteer-to-istanbul}.
*
* @example
* An example of using JavaScript and CSS coverage to get percentage of initially
* executed code:
* ```js
* // Enable both JavaScript and CSS coverage
* await Promise.all([
* page.coverage.startJSCoverage(),
* page.coverage.startCSSCoverage()
* ]);
* // Navigate to page
* await page.goto('https://example.com');
* // Disable both JavaScript and CSS coverage
* const [jsCoverage, cssCoverage] = await Promise.all([
* page.coverage.stopJSCoverage(),
* page.coverage.stopCSSCoverage(),
* ]);
* let totalBytes = 0;
* let usedBytes = 0;
* const coverage = [...jsCoverage, ...cssCoverage];
* for (const entry of coverage) {
* totalBytes += entry.text.length;
* for (const range of entry.ranges)
* usedBytes += range.end - range.start - 1;
* }
* console.log(`Bytes used: ${usedBytes / totalBytes * 100}%`);
* ```
* @public
*/
export class Coverage {
constructor(client) {
this._jsCoverage = new JSCoverage(client);
this._cssCoverage = new CSSCoverage(client);
}
/**
* @param options - Set of configurable options for coverage defaults to
* `resetOnNavigation : true, reportAnonymousScripts : false`
* @returns Promise that resolves when coverage is started.
*
* @remarks
* Anonymous scripts are ones that don't have an associated url. These are
* scripts that are dynamically created on the page using `eval` or
* `new Function`. If `reportAnonymousScripts` is set to `true`, anonymous
* scripts will have `__puppeteer_evaluation_script__` as their URL.
*/
async startJSCoverage(options = {}) {
return await this._jsCoverage.start(options);
}
/**
* @returns Promise that resolves to the array of coverage reports for
* all scripts.
*
* @remarks
* JavaScript Coverage doesn't include anonymous scripts by default.
* However, scripts with sourceURLs are reported.
*/
async stopJSCoverage() {
return await this._jsCoverage.stop();
}
/**
* @param options - Set of configurable options for coverage, defaults to
* `resetOnNavigation : true`
* @returns Promise that resolves when coverage is started.
*/
async startCSSCoverage(options = {}) {
return await this._cssCoverage.start(options);
}
/**
* @returns Promise that resolves to the array of coverage reports
* for all stylesheets.
* @remarks
* CSS Coverage doesn't include dynamically injected style tags
* without sourceURLs.
*/
async stopCSSCoverage() {
return await this._cssCoverage.stop();
}
}
/**
* @public
*/
export class JSCoverage {
constructor(client) {
this._enabled = false;
this._scriptURLs = new Map();
this._scriptSources = new Map();
this._eventListeners = [];
this._resetOnNavigation = false;
this._reportAnonymousScripts = false;
this._includeRawScriptCoverage = false;
this._client = client;
}
async start(options = {}) {
assert(!this._enabled, 'JSCoverage is already enabled');
const { resetOnNavigation = true, reportAnonymousScripts = false, includeRawScriptCoverage = false, } = options;
this._resetOnNavigation = resetOnNavigation;
this._reportAnonymousScripts = reportAnonymousScripts;
this._includeRawScriptCoverage = includeRawScriptCoverage;
this._enabled = true;
this._scriptURLs.clear();
this._scriptSources.clear();
this._eventListeners = [
helper.addEventListener(this._client, 'Debugger.scriptParsed', this._onScriptParsed.bind(this)),
helper.addEventListener(this._client, 'Runtime.executionContextsCleared', this._onExecutionContextsCleared.bind(this)),
];
await Promise.all([
this._client.send('Profiler.enable'),
this._client.send('Profiler.startPreciseCoverage', {
callCount: this._includeRawScriptCoverage,
detailed: true,
}),
this._client.send('Debugger.enable'),
this._client.send('Debugger.setSkipAllPauses', { skip: true }),
]);
}
_onExecutionContextsCleared() {
if (!this._resetOnNavigation)
return;
this._scriptURLs.clear();
this._scriptSources.clear();
}
async _onScriptParsed(event) {
// Ignore puppeteer-injected scripts
if (event.url === EVALUATION_SCRIPT_URL)
return;
// Ignore other anonymous scripts unless the reportAnonymousScripts option is true.
if (!event.url && !this._reportAnonymousScripts)
return;
try {
const response = await this._client.send('Debugger.getScriptSource', {
scriptId: event.scriptId,
});
this._scriptURLs.set(event.scriptId, event.url);
this._scriptSources.set(event.scriptId, response.scriptSource);
}
catch (error) {
// This might happen if the page has already navigated away.
debugError(error);
}
}
async stop() {
assert(this._enabled, 'JSCoverage is not enabled');
this._enabled = false;
const result = await Promise.all([
this._client.send('Profiler.takePreciseCoverage'),
this._client.send('Profiler.stopPreciseCoverage'),
this._client.send('Profiler.disable'),
this._client.send('Debugger.disable'),
]);
helper.removeEventListeners(this._eventListeners);
const coverage = [];
const profileResponse = result[0];
for (const entry of profileResponse.result) {
let url = this._scriptURLs.get(entry.scriptId);
if (!url && this._reportAnonymousScripts)
url = 'debugger://VM' + entry.scriptId;
const text = this._scriptSources.get(entry.scriptId);
if (text === undefined || url === undefined)
continue;
const flattenRanges = [];
for (const func of entry.functions)
flattenRanges.push(...func.ranges);
const ranges = convertToDisjointRanges(flattenRanges);
if (!this._includeRawScriptCoverage) {
coverage.push({ url, ranges, text });
}
else {
coverage.push({ url, ranges, text, rawScriptCoverage: entry });
}
}
return coverage;
}
}
/**
* @public
*/
export class CSSCoverage {
constructor(client) {
this._enabled = false;
this._stylesheetURLs = new Map();
this._stylesheetSources = new Map();
this._eventListeners = [];
this._resetOnNavigation = false;
this._reportAnonymousScripts = false;
this._client = client;
}
async start(options = {}) {
assert(!this._enabled, 'CSSCoverage is already enabled');
const { resetOnNavigation = true } = options;
this._resetOnNavigation = resetOnNavigation;
this._enabled = true;
this._stylesheetURLs.clear();
this._stylesheetSources.clear();
this._eventListeners = [
helper.addEventListener(this._client, 'CSS.styleSheetAdded', this._onStyleSheet.bind(this)),
helper.addEventListener(this._client, 'Runtime.executionContextsCleared', this._onExecutionContextsCleared.bind(this)),
];
await Promise.all([
this._client.send('DOM.enable'),
this._client.send('CSS.enable'),
this._client.send('CSS.startRuleUsageTracking'),
]);
}
_onExecutionContextsCleared() {
if (!this._resetOnNavigation)
return;
this._stylesheetURLs.clear();
this._stylesheetSources.clear();
}
async _onStyleSheet(event) {
const header = event.header;
// Ignore anonymous scripts
if (!header.sourceURL)
return;
try {
const response = await this._client.send('CSS.getStyleSheetText', {
styleSheetId: header.styleSheetId,
});
this._stylesheetURLs.set(header.styleSheetId, header.sourceURL);
this._stylesheetSources.set(header.styleSheetId, response.text);
}
catch (error) {
// This might happen if the page has already navigated away.
debugError(error);
}
}
async stop() {
assert(this._enabled, 'CSSCoverage is not enabled');
this._enabled = false;
const ruleTrackingResponse = await this._client.send('CSS.stopRuleUsageTracking');
await Promise.all([
this._client.send('CSS.disable'),
this._client.send('DOM.disable'),
]);
helper.removeEventListeners(this._eventListeners);
// aggregate by styleSheetId
const styleSheetIdToCoverage = new Map();
for (const entry of ruleTrackingResponse.ruleUsage) {
let ranges = styleSheetIdToCoverage.get(entry.styleSheetId);
if (!ranges) {
ranges = [];
styleSheetIdToCoverage.set(entry.styleSheetId, ranges);
}
ranges.push({
startOffset: entry.startOffset,
endOffset: entry.endOffset,
count: entry.used ? 1 : 0,
});
}
const coverage = [];
for (const styleSheetId of this._stylesheetURLs.keys()) {
const url = this._stylesheetURLs.get(styleSheetId);
const text = this._stylesheetSources.get(styleSheetId);
const ranges = convertToDisjointRanges(styleSheetIdToCoverage.get(styleSheetId) || []);
coverage.push({ url, ranges, text });
}
return coverage;
}
}
function convertToDisjointRanges(nestedRanges) {
const points = [];
for (const range of nestedRanges) {
points.push({ offset: range.startOffset, type: 0, range });
points.push({ offset: range.endOffset, type: 1, range });
}
// Sort points to form a valid parenthesis sequence.
points.sort((a, b) => {
// Sort with increasing offsets.
if (a.offset !== b.offset)
return a.offset - b.offset;
// All "end" points should go before "start" points.
if (a.type !== b.type)
return b.type - a.type;
const aLength = a.range.endOffset - a.range.startOffset;
const bLength = b.range.endOffset - b.range.startOffset;
// For two "start" points, the one with longer range goes first.
if (a.type === 0)
return bLength - aLength;
// For two "end" points, the one with shorter range goes first.
return aLength - bLength;
});
const hitCountStack = [];
const results = [];
let lastOffset = 0;
// Run scanning line to intersect all ranges.
for (const point of points) {
if (hitCountStack.length &&
lastOffset < point.offset &&
hitCountStack[hitCountStack.length - 1] > 0) {
const lastResult = results.length ? results[results.length - 1] : null;
if (lastResult && lastResult.end === lastOffset)
lastResult.end = point.offset;
else
results.push({ start: lastOffset, end: point.offset });
}
lastOffset = point.offset;
if (point.type === 0)
hitCountStack.push(point.range.count);
else
hitCountStack.pop();
}
// Filter out empty ranges.
return results.filter((range) => range.end - range.start > 1);
}
//# sourceMappingURL=Coverage.js.map