如何在 puppeteer page.evaluate 中使用 url 模块
How to use url module in puppeteer page.evaluate
我已经尝试了 Error: Evaluation Failed: ReferenceError: util is not defined and 中提到的所有内容。具体来说,我试过使用 browserify 转换 url.js(我也试过一起转换 url.js 和 punycode.js),并且我添加了相应的脚本(bundle.js)到页面环境。
我正在尝试在 puppeteer 中使用 page.evaluate() 中的 url 模块。这是一个显示错误的非常简单的示例:
const puppeteer = require('puppeteer');
puppeteer.launch({dumpio: true}).then(async browser => {
const page = await browser.newPage();
const response = await page.goto('https://www.google.com');
await page.waitFor(5000);
const pageUrl = page.url();
await page.addScriptTag({path: 'bundle.js'});
await page.evaluate(pageUrl => {
const anchors = Array.from(document.querySelectorAll('a'));
for (let anchor of anchors) {
const href = anchor.getAttribute('href');
let hrefUrl;
try {
hrefUrl = new URL(href);
} catch (e) {
hrefUrl = new URL(href, pageUrl);
}
console.log(url.format(hrefUrl, {fragment: false}));
}
}, pageUrl);
await page.close();
await browser.close();
});
此示例生成以下错误:
(node:23667) UnhandledPromiseRejectionWarning: Error: Evaluation
failed: ReferenceError: url is not defined
at pageUrl (puppeteer_evaluation_script:11:19)
at ExecutionContext.evaluateHandle (/home/webb/node_modules/puppeteer/lib/ExecutionContext.js:97:13)
at
at process._tickCallback (internal/process/next_tick.js:188:7)
我还需要做什么才能识别 url 模块?
与 page.exposeFunction()
的变体:
'use strict';
const url = require('url');
const puppeteer = require('puppeteer');
puppeteer.launch({ dumpio: true }).then(async browser => {
const page = await browser.newPage();
await page.exposeFunction('formatURL', formatURL);
const response = await page.goto('https://www.google.com');
await page.waitFor(5000);
const pageUrl = page.url();
await page.evaluate(async (pageUrl) => {
const anchors = Array.from(document.querySelectorAll('a'));
for (const anchor of anchors) {
const href = anchor.getAttribute('href');
const hrefUrl = await formatURL(href, pageUrl);
console.log(hrefUrl);
}
}, pageUrl);
await page.close();
await browser.close();
});
function formatURL(href, base) {
try {
return url.format(new URL(href), { fragment: false });
} catch (e) {
return url.format(new URL(href, base), { fragment: false });
}
}
使用page.exposeFunction
公开url
包中的所有函数。
迭代模块的导出并添加每个函数以公开
var url = require('url');
var functionsToExpose = [];
for(let key of Object.keys(url)){
if(typeof url[key] == 'function'){
functionsToExpose.push({name: 'url'+key, func: url[key]});
}
}
将它们公开到页面
for(let item of functionsToExpose){
await page.exposeFunction(item.name, item.func);
}
url 包的每个函数都将被重命名。 url.parse
可使用 urlparse
.
访问
我已经尝试了 Error: Evaluation Failed: ReferenceError: util is not defined and
我正在尝试在 puppeteer 中使用 page.evaluate() 中的 url 模块。这是一个显示错误的非常简单的示例:
const puppeteer = require('puppeteer');
puppeteer.launch({dumpio: true}).then(async browser => {
const page = await browser.newPage();
const response = await page.goto('https://www.google.com');
await page.waitFor(5000);
const pageUrl = page.url();
await page.addScriptTag({path: 'bundle.js'});
await page.evaluate(pageUrl => {
const anchors = Array.from(document.querySelectorAll('a'));
for (let anchor of anchors) {
const href = anchor.getAttribute('href');
let hrefUrl;
try {
hrefUrl = new URL(href);
} catch (e) {
hrefUrl = new URL(href, pageUrl);
}
console.log(url.format(hrefUrl, {fragment: false}));
}
}, pageUrl);
await page.close();
await browser.close();
});
此示例生成以下错误:
(node:23667) UnhandledPromiseRejectionWarning: Error: Evaluation failed: ReferenceError: url is not defined at pageUrl (puppeteer_evaluation_script:11:19) at ExecutionContext.evaluateHandle (/home/webb/node_modules/puppeteer/lib/ExecutionContext.js:97:13) at at process._tickCallback (internal/process/next_tick.js:188:7)
我还需要做什么才能识别 url 模块?
与 page.exposeFunction()
的变体:
'use strict';
const url = require('url');
const puppeteer = require('puppeteer');
puppeteer.launch({ dumpio: true }).then(async browser => {
const page = await browser.newPage();
await page.exposeFunction('formatURL', formatURL);
const response = await page.goto('https://www.google.com');
await page.waitFor(5000);
const pageUrl = page.url();
await page.evaluate(async (pageUrl) => {
const anchors = Array.from(document.querySelectorAll('a'));
for (const anchor of anchors) {
const href = anchor.getAttribute('href');
const hrefUrl = await formatURL(href, pageUrl);
console.log(hrefUrl);
}
}, pageUrl);
await page.close();
await browser.close();
});
function formatURL(href, base) {
try {
return url.format(new URL(href), { fragment: false });
} catch (e) {
return url.format(new URL(href, base), { fragment: false });
}
}
使用page.exposeFunction
公开url
包中的所有函数。
迭代模块的导出并添加每个函数以公开
var url = require('url');
var functionsToExpose = [];
for(let key of Object.keys(url)){
if(typeof url[key] == 'function'){
functionsToExpose.push({name: 'url'+key, func: url[key]});
}
}
将它们公开到页面
for(let item of functionsToExpose){
await page.exposeFunction(item.name, item.func);
}
url 包的每个函数都将被重命名。 url.parse
可使用 urlparse
.