python Playwright 教程

官方文档：https://playwright.dev/docs/intro

1、Playwright介绍

Playwright是一个强大的Python库，仅用一个API即可自动执行Chromium、Firefox、WebKit等主流浏览器自动化操作，并同时支持以无头模式、有头模式运行。

Playwright提供的自动化技术是绿色的、功能强大、可靠且快速，支持Linux、Mac以及Windows操作系统。

ps:博主以前都是用selenium来做ui自动化测试的, 部署的时候，还得额外安装一个本地浏览器，或者去制作一个绿色免安装版的浏览器（mac、linux还不知道怎么制作）非常的不喜欢。Playwright可以避免这种问题，Playwright安装后，直接是打开浏览器引擎Chromium、Firefox、WebKit进行驱动操作，绿色且快速。

二、安装

安装playwright库

pip install playwright

安装浏览器驱动文件（安装过程稍微有点慢）
python -m playwright install

安装成功后可查看帮助

python -m playwright codegen --help


Usage: playwright codegen [options] [url]

open page and generate code for user actions

Options:
  -o, --output         saves the generated script to a file
  --target              language to generate, one of javascript, test, python, python-async, pytest, csharp, java (default: "python")
  --save-trace          record a trace for the session and save it to a file
  -b, --browser      browser to use, one of cr, chromium, ff, firefox, wk, webkit (default: "chromium")
  --block-service-workers         block service workers
  --channel              Chromium distribution channel, "chrome", "chrome-beta", "msedge-dev", etc
  --color-scheme          emulate preferred color scheme, "light" or "dark"
  --device            emulate device, for example  "iPhone 11"
  --geolocation      specify geolocation coordinates, for example "37.819722,-122.478611"
  --ignore-https-errors           ignore https errors
  --load-storage        load context storage state from the file, previously saved with --save-storage
  --lang                specify language / locale, for example "en-GB"
  --proxy-server           specify proxy server, for example "http://myproxy:3128" or "socks5://myproxy:8080"
  --proxy-bypass          comma-separated domains to bypass proxy, for example ".com,chromium.org,.domain.com"
  --save-har            save HAR file with all network activity at the end
  --save-har-glob   filter entries in the HAR by matching url against this glob pattern
  --save-storage        save context storage state at the end, for later use with --load-storage
  --timezone           time zone to emulate, for example "Europe/Rome"
  --timeout              timeout for Playwright actions in milliseconds, no timeout by default
  --user-agent         specify user agent string
  --viewport-size           specify browser viewport size in pixels, for example "1280, 720"
  -h, --help                      display help for command

Examples:

  $ codegen
  $ codegen --target=python
  $ codegen -b webkit https://example.com

帮助解析

options含义：

-o：将录制的脚本保存到一个文件

--target：规定生成脚本的语言，有JS和Python两种，默认为Python

-b：指定浏览器驱动

我们可以执行一行命令打开浏览器录制操作并生成脚本，例如：

python -m playwright codegen --target python -o 'demo.py' -b chromium https://www.baidu.com

录制关闭后，自动生成demo.py脚本，执行demo.py可以回放。（ps：滚动操作无法录制到，得自己修改代码，添加滚动操作）

demo.py

from playwright.sync_api import Playwright, sync_playwright, expect


def run(playwright: Playwright) -> None:
    browser = playwright.chromium.launch(headless=False)
    context = browser.new_context()

    # Open new page
    page = context.new_page()

    # Go to https://www.baidu.com/
    page.goto("https://www.baidu.com/")

    # Click input[name="wd"]
    page.locator("input[name=\"wd\"]").click()

    # Fill input[name="wd"]
    page.locator("input[name=\"wd\"]").fill("Playwright")

    # Click text=百度一下
    page.locator("text=百度一下").click()
    page.wait_for_url("https://www.baidu.com/s?ie=utf-8&f=8&rsv_bp=1&rsv_idx=1&tn=baidu&wd=Playwright&fenlei=256&rsv_pq=dc316e380004ede0&rsv_t=8fd9RWXb83JO2c9YXPfB1V6gwx%2F4Yt3sFpHTOQjLhfEwx3pjr%2Bkui28W74ox&rqlang=en&rsv_enter=0&rsv_dl=tb&rsv_sug3=2&rsv_sug1=1&rsv_sug7=100&rsv_btype=i&prefixsug=Playwright&rsp=0&inputT=1949&rsv_sug4=2154")

    # Close page
    page.close()

    # ---------------------
    context.close()
    browser.close()


with sync_playwright() as playwright:
    run(playwright)

Playwright的更多优点可查看官方文档 https://playwright.dev/docs/intro