python的pyppeteer的爬虫demo

目标网站是药物临床试验登记平台

思路：尝试requests库直接获取该网站的response，失败，因为该网站返回202，需要破解js；然后尝试用chrome driver驱动获取网页数据，失败，因为被识别为恶意爬虫；然后找到了pyppeteer库进行尝试，成功

贴代码：

import asyncio
import random

from pyppeteer import launch
from pyppeteer.network_manager import Response


class PyppeteerScript(object):
    """
    pyppeteer
    """

    def __init__(self):
        self.base_url = "http://www.chinadrugtrials.org.cn/clinicaltrials.searchlistdetail.dhtml"
        # 从第几个开始爬取
        self.current_page = 13480
        # 可爬取的最大实验数 退出的条件
        self.page_limit = 13483
        self.config = {
            # 无头浏览器设置 显示网页
            "headless": False,
            # 本地Chromium路径 镜像下载:https://npm.taobao.org/mirrors/chromium-browser-snapshots/
            "executablePath": "/Users/xxx/Downloads/chromium/Chromium.app/Contents/MacOS/Chromium",
            # 操作后的延迟时间 防止检测
            "slowMo": 5,
            # 配置参数
            "args": [
                # 关闭自动化提示框
                "--disable-infobars",
                # 关闭沙盒模式
                "--no-sandbox",
                # 代理 PS:每次需要更换代理就需要重新通过launch方法来启动浏览器
                # "--proxy-server=http://ip:port",
                # 取消显示正在受控制的bars
                "--disable-infobars",
            ]
        }

    async def intercept_response(self, res: Response):
        json_text = await res.text()
        print(json_text)

    def __save_html(self, content, name):
        with open("./html/{}.html".format(name), "w+", encoding="utf-8") as f:
            f.write(content)

    async def run(self):
        """
        入口函数
        """
        browser = await launch(**self.config)
        page = await browser.newPage()
        await page.setViewport({'width': 1920, 'height': 1080})

        await page.setUserAgent(
            'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_9_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/66.0.3359.181 Safari/537.36'
        );

        # 混淆识别js代码 防止被识别
        js_text = """
            () =>{ 
                Object.defineProperties(navigator,{ webdriver:{ get: () => false } });
                window.navigator.chrome = { runtime: {},  };
                Object.defineProperty(navigator, 'languages', { get: () => ['en-US', 'en'] });
                Object.defineProperty(navigator, 'plugins', { get: () => [1, 2, 3, 4, 5,6], });
            }
            """
        await page.evaluateOnNewDocument(js_text)

        await page.goto(url=self.base_url)
        # 等待网页加载(second)
        await asyncio.sleep(5)

        while True:
            if self.current_page > self.page_limit:
                break

            # 执行翻页的JS函数
            turn_page_js = "gotopage({})".format(self.current_page)
            await page.evaluate(turn_page_js)
            await asyncio.sleep(random.randint(2, 4))
            self.current_page += 1

            # 获取网页源码
            page_text = await page.content()
            page_title = await page.title()
            self.__save_html(content=page_text, name=page_title)

            # 没有XHR请求 不会响应response 不能直接获取json
            # await page.setRequestInterception(True)
            # page.on('response', self.intercept_response)

        await browser.close()


if __name__ == '__main__':
    asyncio.get_event_loop().run_until_complete(PyppeteerScript().run())

PS：该代码仅供学习交流，请勿用于其他商业用途

标签：__,await,python,demo,self,pyppeteer,js,text,page
来源： https://blog.csdn.net/weixin_50385593/article/details/117634794