playwright下载及基本使用

1. 下载playwright库

pip install playwright==1.33.0
playwright install 

2. playwright使用

2.1导入库

from playwright.sync_api import sync_playwright

2.2 基本使用

• 启动引擎，实例化对象

   browser = playwright.chromium.launch(
   headless=False,channel='chrome') 
  

• 创建上下文context

  context = browser.new_context() 
  

• 创建页面对象

  page= context.new_page()
  

• 页面请求

  page.goto('https://www.baidu.com/')
  

• 页面关闭

  context.close()
  browser.close()  
  

• 禁止加载图片

  import re
  # 禁止加载图片，加速加载
  def cancel_request(route):
      route.abort()
  
  page.route(re.compile(r"(.png)|(.jpg)"), cancel_request)
  

• 窗口最大化
  • 设置参数args=['--start-maximized']和no_viewport=True

  with sync_playwright() as playwright:
      browser = playwright.chromium.launch(
          headless=False,
          args=['--start-maximized'], # 窗口大小打开最大
      )  # 启动引擎，实例化对象
      context = browser.new_context(no_viewport=True)  #显示最大窗口
      page = context.new_page()
      page.goto(url)
  
      context.close()
      browser.close()
  

• 请求百度总代码

  from playwright.sync_api import sync_playwright
  
  url='https://www.baidu.com/'
  with sync_playwright() as playwright:
      browser = playwright.chromium.launch(
          headless=True,              # 无头
          args=['--start-maximized'], # 窗口大小打开最大
          channel='chrome'            # 使用google浏览器打开
      )                               # 启动引擎，实例化对象
                                      # no_viewport=True显示最大窗口
      context = browser.new_context(no_viewport=True) # 需要创建一个 context，这是一个新的概念，不同于selenium，以后更为方便管理 cookies 和 ip代理
      
      page = context.new_page()
      page.goto(url)
  
      context.close()
      browser.close()
  

3.XPATH元素定位方法

• xpath教程·
  • xpath基本使用

3.1 xpath定位语法

• 点位xpath语句前加xpath=即可

   input_xpath = 'xpath= //input[@id="su"]'
  

3.2 相关操作

• 点击元素

  page.locator(input_xpath).click()
  

• 获取元素属性

  attribute1 = page.get_attribute(input_xpath, 'value')   # 获取元素value值
  attribute2= page.get_attribute(input_xpath, 'href')     # 获取元素href值
  attribute3 = page.get_attribute(input_xpath, 'src')     # 获取元素src值
  attribute4 = page.get_attribute(input_xpath, 'id')  # 获取元素id值
  

• 获取元素文本

  text1=page.locator(ul).all_inner_texts()  # 获取所有元素列表
  text2=page.locator(ul).inner_text()    # 所有元素字符串,所有文本变为一整个字符串
  

4. 等待及缓存

4.1 等待操作

• 强制等待

  import time
  time.sleep(n)  
  

• playwright强制等待

  page.wait_for_timeout(1000) # 单位ms
  

• 设置访问最长等待时长
  • 请求操作设置时长

    page.goto(url, timeout=1000)  # 单位ms
    

  • 点击操作设置时长

    page.locator(href_xpath).click(timeout=1000)   # 单位ms
    

4.2 添加缓存

• 添加缓存，提高加载速度

  from playwright.sync_api import Playwright, sync_playwright
  
  def run(playwright: Playwright) -> None:
      browser = playwright.firefox.launch_persistent_context(headless=False, args=['--start-maximized'],
                                                             user_data_dir=os.path.join(root_path, 'user_data'),# 保存缓存地址
                                                             accept_downloads=True, slow_mo=250)
      page = browser.new_page()
      page.goto('https://www.baidu.com/')
  
      browser.close()
  with sync_playwright() as playwright:
      run(playwright)