使用scrapy+splash+Lua脚本实现滚轮动态加载爬取CSDN

﹏ヽ暗。殇╰゛Y 2022-05-10 12:20 49阅读 0赞

爬取CSDN的时候发现，csdn需要一直使用鼠标滑轮下拉，动态加载

![70][]

使用Lua脚本，详细解释见官方文档[https://splash.readthedocs.io/en/stable/][https_splash.readthedocs.io_en_stable]

function main(splash, args)
      splash:go(args.url)
      local scroll_to = splash:jsfunc("window.scrollTo")
      scroll_to(0, 300)
      splash:set_viewport_full()
      return {png=splash:png()}
    end

![70 1][]

发现可以获取到滑动以后的内容

![70 2][]

接下来就是如何将该脚本结合到scrapy中，工具使用的是pycharm

class CSDNSpider(scrapy.Spider):
    
        name = 'test'
        def start_requests(self):
    
            # script = """
            #             function main(splash,args)
            #                 splash:set_viewport_size(1028, 10000)
            #                 splash:go(args.url)
            #                 local scroll_to = splash:jsfunc("window.scrollTo")
            #                 scroll_to(0, 2500)
            #                 splash:wait(5)
            #                 return {
            #                     html = splash:html()
            #                 }
            #             end
            #             """
            script = """
                    function main(splash, args)
                      splash:go(args.url)
                      local scroll_to = splash:jsfunc("window.scrollTo")
                      scroll_to(0, 2800)
                      splash:set_viewport_full()
                      splash:wait(5)
                      return {html=splash:html()}
                    end
            """
            url = 'https://blog.csdn.net/'
            yield SplashRequest(url, self.parse,  endpoint='execute', args={'lua_source': script, 'url': url})

使用SplashRequest请求通过args传递参数，如果是scrapy.Request则是meta

然后还有一步就是将setting设置好（原来设置过，然后新的工程忘了设置，搞了好久才发现是这得问题）

# -*- coding: utf-8 -*-
    
    # Scrapy settings for Technology project
    #
    # For simplicity, this file contains only settings considered important or
    # commonly used. You can find more settings consulting the documentation:
    #
    #     https://doc.scrapy.org/en/latest/topics/settings.html
    #     https://doc.scrapy.org/en/latest/topics/downloader-middleware.html
    #     https://doc.scrapy.org/en/latest/topics/spider-middleware.html
    
    BOT_NAME = 'Technology'
    
    SPIDER_MODULES = ['Technology.spiders']
    NEWSPIDER_MODULE = 'Technology.spiders'
    
    
    # Crawl responsibly by identifying yourself (and your website) on the user-agent
    #USER_AGENT = 'Technology (+http://www.yourdomain.com)'
    
    # Obey robots.txt rules
    ROBOTSTXT_OBEY = True
    
    # Configure maximum concurrent requests performed by Scrapy (default: 16)
    #CONCURRENT_REQUESTS = 32
    
    # Configure a delay for requests for the same website (default: 0)
    # See https://doc.scrapy.org/en/latest/topics/settings.html#download-delay
    # See also autothrottle settings and docs
    #DOWNLOAD_DELAY = 3
    # The download delay setting will honor only one of:
    #CONCURRENT_REQUESTS_PER_DOMAIN = 16
    #CONCURRENT_REQUESTS_PER_IP = 16
    
    # Disable cookies (enabled by default)
    #COOKIES_ENABLED = False
    
    # Disable Telnet Console (enabled by default)
    #TELNETCONSOLE_ENABLED = False
    
    # Override the default request headers:
    #DEFAULT_REQUEST_HEADERS = {
    #   'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8',
    #   'Accept-Language': 'en',
    #}
    
    # Enable or disable spider middlewares
    # See https://doc.scrapy.org/en/latest/topics/spider-middleware.html
    #SPIDER_MIDDLEWARES = {
    #    'Technology.middlewares.TechnologySpiderMiddleware': 543,
    #}
    
    # Enable or disable downloader middlewares
    # See https://doc.scrapy.org/en/latest/topics/downloader-middleware.html
    DOWNLOADER_MIDDLEWARES = {
        'scrapy_splash.SplashCookiesMiddleware':723,
        'scrapy_splash.SplashMiddleware':725,
        'scrapy.downloadermiddlewares.httpcompression.HttpCompressionMiddleware': 810,#不配置查不到信息
       # 'Technology.middlewares.TechnologyDownloaderMiddleware': 543,
    }
    
    # Enable or disable extensions
    # See https://doc.scrapy.org/en/latest/topics/extensions.html
    #EXTENSIONS = {
    #    'scrapy.extensions.telnet.TelnetConsole': None,
    #}
    
    # Configure item pipelines
    # See https://doc.scrapy.org/en/latest/topics/item-pipeline.html
    #ITEM_PIPELINES = {
    #    'Technology.pipelines.TechnologyPipeline': 300,
    #}
    
    # Enable and configure the AutoThrottle extension (disabled by default)
    # See https://doc.scrapy.org/en/latest/topics/autothrottle.html
    #AUTOTHROTTLE_ENABLED = True
    # The initial download delay
    #AUTOTHROTTLE_START_DELAY = 5
    # The maximum download delay to be set in case of high latencies
    #AUTOTHROTTLE_MAX_DELAY = 60
    # The average number of requests Scrapy should be sending in parallel to
    # each remote server
    #AUTOTHROTTLE_TARGET_CONCURRENCY = 1.0
    # Enable showing throttling stats for every response received:
    #AUTOTHROTTLE_DEBUG = False
    
    # Enable and configure HTTP caching (disabled by default)
    # See https://doc.scrapy.org/en/latest/topics/downloader-middleware.html#httpcache-middleware-settings
    HTTPCACHE_ENABLED = True
    HTTPCACHE_EXPIRATION_SECS = 0
    HTTPCACHE_DIR = 'httpcache'
    #HTTPCACHE_IGNORE_HTTP_CODES = []
    #HTTPCACHE_STORAGE = 'scrapy.extensions.httpcache.FilesystemCacheStorage'
    SPLASH_URL = "http://192.168.99.100:8050"      #自己安装的docker里的splash位置
    DUPEFILTER_CLASS = "scrapy_splash.SplashAwareDupeFilter"
    HTTPCACHE_STORAGE = 'scrapy_splash.SplashAwareFSCacheStorage'

设置好以后就大功告成。

在前面的脚本那花费了好长时间，网上的资料都不全

安装docker见另一篇文章[安装splash及解决点击Docker出现windows 正在查找bash.exe。如果想亲自查找文件，请点击“浏览”的问题][splash_Docker_windows _bash.exe]

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![20190303191855385.jpg][]

[70]: /images/20220510/940a396b20914d2e88423439e7ec2e63.png
[https_splash.readthedocs.io_en_stable]: https://splash.readthedocs.io/en/stable/
[70 1]: /images/20220510/178d9f971b094571b0efa2c3658ec602.png
[70 2]: /images/20220510/98ac68e82d944bffb7df24f5e19d6f21.png
[splash_Docker_windows _bash.exe]: https://blog.csdn.net/zhao_5352269/article/details/82850496
[20190303191855385.jpg]: /images/20220510/b3c18221fe824de584d1e2ba856cba2d.png