Playwright-go: Golang跨浏览器自动化控制库

Playwright-go是Microsoft Playwright的Golang绑定，它允许你通过代码自动化控制Chromium、Firefox和WebKit浏览器，实现端到端的测试和网页自动化操作。

安装Playwright-go

首先需要安装Playwright-go库：

go get github.com/playwright-community/playwright-go

然后安装所需的浏览器二进制文件：

go run github.com/playwright-community/playwright-go/cmd/playwright install

基本使用示例

1. 启动浏览器并访问页面

package main

import (
	"log"

	"github.com/playwright-community/playwright-go"
)

func main() {
	pw, err := playwright.Run()
	if err != nil {
		log.Fatalf("could not start playwright: %v", err)
	}
	defer pw.Stop()

	browser, err := pw.Chromium.Launch()
	if err != nil {
		log.Fatalf("could not launch browser: %v", err)
	}
	defer browser.Close()

	page, err := browser.NewPage()
	if err != nil {
		log.Fatalf("could not create page: %v", err)
	}

	if _, err = page.Goto("https://example.com"); err != nil {
		log.Fatalf("could not goto: %v", err)
	}

	title, err := page.Title()
	if err != nil {
		log.Fatalf("could not get title: %v", err)
	}
	log.Printf("Page title: %s", title)
}

2. 填写表单并提交

func fillForm() {
	// ...前面的初始化代码同上...

	page, err := browser.NewPage()
	if err != nil {
		log.Fatalf("could not create page: %v", err)
	}

	if _, err = page.Goto("https://example.com/login"); err != nil {
		log.Fatalf("could not goto: %v", err)
	}

	// 填写用户名和密码
	if err = page.Locator("#username").Fill("testuser"); err != nil {
		log.Fatalf("could not fill username: %v", err)
	}
	if err = page.Locator("#password").Fill("password123"); err != nil {
		log.Fatalf("could not fill password: %v", err)
	}

	// 点击登录按钮
	if err = page.Locator("button[type='submit']").Click(); err != nil {
		log.Fatalf("could not click submit button: %v", err)
	}

	// 等待导航完成
	page.WaitForNavigation()
}

3. 截图和PDF生成

func takeScreenshotAndPDF() {
	// ...初始化代码...
	
	page, err := browser.NewPage()
	if err != nil {
		log.Fatalf("could not create page: %v", err)
	}

	if _, err = page.Goto("https://example.com"); err != nil {
		log.Fatalf("could not goto: %v", err)
	}

	// 截图
	if _, err = page.Screenshot(playwright.PageScreenshotOptions{
		Path: playwright.String("screenshot.png"),
	}); err != nil {
		log.Fatalf("could not take screenshot: %v", err)
	}

	// 生成PDF
	pdfData, err := page.PDF(playwright.PagePdfOptions{
		Path: playwright.String("page.pdf"),
	})
	if err != nil {
		log.Fatalf("could not generate PDF: %v", err)
	}
	log.Printf("Generated PDF with %d bytes", len(pdfData))
}

高级功能

1. 处理iframe

func handleIframe() {
	// ...初始化代码...
	
	page, err := browser.NewPage()
	if err != nil {
		log.Fatalf("could not create page: %v", err)
	}

	if _, err = page.Goto("https://example.com/iframe-page"); err != nil {
		log.Fatalf("could not goto: %v", err)
	}

	// 获取iframe
	frame := page.Frame("iframe-name")
	if frame == nil {
		frame = page.FrameByURL("https://example.com/iframe-content")
	}

	// 在iframe内操作
	if frame != nil {
		if err = frame.Locator("#iframe-button").Click(); err != nil {
			log.Fatalf("could not click iframe button: %v", err)
		}
	}
}

2. 模拟移动设备

func emulateMobile() {
	// ...初始化代码...
	
	iphone := playwright.Devices["iPhone 11"]
	context, err := browser.NewContext(playwright.BrowserNewContextOptions{
		Viewport:    iphone.Viewport,
		UserAgent:   iphone.UserAgent,
		DeviceScaleFactor: iphone.DeviceScaleFactor,
		IsMobile:    iphone.IsMobile,
		HasTouch:    iphone.HasTouch,
	})
	if err != nil {
		log.Fatalf("could not create context: %v", err)
	}
	defer context.Close()

	page, err := context.NewPage()
	if err != nil {
		log.Fatalf("could not create page: %v", err)
	}

	if _, err = page.Goto("https://example.com"); err != nil {
		log.Fatalf("could not goto: %v", err)
	}
}

3. 网络拦截和模拟

func interceptRequests() {
	// ...初始化代码...
	
	page, err := browser.NewPage()
	if err != nil {
		log.Fatalf("could not create page: %v", err)
	}

	// 拦截所有请求
	err = page.Route("**/*", func(route playwright.Route) {
		// 屏蔽图片请求
		if route.Request().ResourceType() == "image" {
			route.Abort()
		} else {
			route.Continue()
		}
	})
	if err != nil {
		log.Fatalf("could not set up route: %v", err)
	}

	if _, err = page.Goto("https://example.com"); err != nil {
		log.Fatalf("could not goto: %v", err)
	}
}

测试示例

Playwright-go非常适合用于端到端测试：

func TestLogin(t *testing.T) {
	pw, err := playwright.Run()
	if err != nil {
		t.Fatalf("could not start playwright: %v", err)
	}
	defer pw.Stop()

	browser, err := pw.Chromium.Launch()
	if err != nil {
		t.Fatalf("could not launch browser: %v", err)
	}
	defer browser.Close()

	page, err := browser.NewPage()
	if err != nil {
		t.Fatalf("could not create page: %v", err)
	}

	if _, err = page.Goto("http://localhost:8080/login"); err != nil {
		t.Fatalf("could not goto: %v", err)
	}

	// 测试登录流程
	if err = page.Locator("#username").Fill("testuser"); err != nil {
		t.Fatalf("could not fill username: %v", err)
	}
	if err = page.Locator("#password").Fill("password123"); err != nil {
		t.Fatalf("could not fill password: %v", err)
	}
	if err = page.Locator("button[type='submit']").Click(); err != nil {
		t.Fatalf("could not click submit button: %v", err)
	}

	// 验证登录成功
	if _, err = page.WaitForSelector(".welcome-message"); err != nil {
		t.Fatalf("login failed: %v", err)
	}
}

总结

Playwright-go提供了强大的跨浏览器自动化能力，主要特点包括：

• 支持Chromium、Firefox和WebKit
• 自动等待元素出现和可操作状态
• 强大的选择器和定位器API
• 网络拦截和模拟功能
• 设备模拟和移动端测试
• 截图和PDF生成

相比传统的Selenium方案，Playwright-go具有更好的性能和更现代的API设计，非常适合用于自动化测试和网页抓取等场景。