一、前言
接着上一篇的笔记,Scrapy爬取普通无反爬、静态页面的网页时可以顺利爬取我们要的信息。但是大部分情况下我们要的数据所在的网页它是动态加载出来的(ajax请求后传回前端页面渲染、js调用function等)。这种情况下需要使用selenium进行模拟人工操作浏览器行为,实现自动化采集动态网页数据。
二、环境搭建
- Scrapy框架的基本依赖包(前几篇有记录)
- selenium依赖包
- pip install selenium==4.0.0a6.post2
- pip install certifi
- pip install urllib3==1.25.11
- 安装Firefox浏览器和对应版本的驱动包
- 火狐浏览器我用的是最新版121.0
- 驱动的版本为0.3.0,见上方资源链接
- 把驱动放到python环境的Scripts文件夹下
三、代码实现
- settings设置
SPIDER_MIDDLEWARES = {'stock_spider.middlewares.StockSpiderSpiderMiddleware': 543,
}DOWNLOADER_MIDDLEWARES = {'stock_spider.middlewares.StockSpiderDownloaderMiddleware': 543,
}ITEM_PIPELINES = {'stock_spider.pipelines.StockSpiderPipeline': 300,
}
- middlewares中间件
from selenium.webdriver.firefox.options import Options as firefox_optionsspider.driver = webdriver.Firefox(options=firefox_options()) # 指定使用的浏览器
- process_request
def process_request(self, request, spider):# Called for each request that goes through the downloader# middleware.# Must either:# - return None: continue processing this request# - or return a Response object# - or return a Request object# - or raise IgnoreRequest: process_exception() methods of# installed downloader middleware will be calledspider.driver.get("http://www.baidu.com")return None
- process_response
from scrapy.http import HtmlResponsedef process_response(self, request, response, spider):# Called with the response returned from the downloader.# Must either;# - return a Response object# - return a Request object# - or raise IgnoreRequestresponse_body = spider.driver.page_sourcereturn HtmlResponse(url=request.url, body=response_body, encoding='utf-8', request=request)
启动爬虫后就可以看到爬虫启动了浏览器驱动,接下来就可以实现各种模拟人工操作了