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  • 提升request模块的效率--线程池

    普通方法:爬取梨视频

    import re
    import time
    import random
    import requests
    from lxml import etree
    
    start_time = time.time()
    
    url = "https://www.pearvideo.com/category_3"
    headers = {
        "User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/79.0.3945.88 Safari/537.36"
    }
    
    ex = 'srcUrl="(.*?)",vdoUrl=srcUrl'
    
    def request_video(url):
        """
        向视频链接发送请求
        """
        return requests.get(url=url, headers=headers).content
    
    def save_video(content):
        """
        将视频的二进制数据保存到本地
        """
        video_name = str(random.randint(100, 999)) + ".mp4"
        with open(video_name, 'wb') as f:
            f.write(content)
    
            
    # 获取首页源码
    page_text = requests.get(url=url, headers=headers).text
    
    tree = etree.HTML(page_text)
    li_list = tree.xpath('//ul[@class="listvideo-list clearfix"]/li')
    
    video_url_list = list()
    for li in li_list:
        detail_url = "https://www.pearvideo.com/" + li.xpath('./div/a/@href')[0]
        
        # 获取该视频页面的源码
        detail_page_text = requests.get(url=detail_url, headers=headers).text
        
        # 正则匹配视频的URL
        video_url = re.findall(ex, detail_page_text, re.S)[0]
        video_url_list.append(video_url)
        
        content = request_video(video_url)
        save_video(content)
    
    
    print("执行耗时: ", time.time() - start_time)

    执行耗时: 147.22410440444946

    使用线程池:爬取梨视频

    # 使用线程池爬去梨视频的
    import re
    import time
    import random
    import requests
    from lxml import etree
    from multiprocessing.dummy import Pool
    
    
    start_time = time.time()
    
    url = "https://www.pearvideo.com/category_3"
    headers = {
        "User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/79.0.3945.88 Safari/537.36"
    }
    
    ex = 'srcUrl="(.*?)",vdoUrl=srcUrl'
    
    def request_video(url):
        """
        向视频链接发送请求
        """
        return requests.get(url=url, headers=headers).content
    
    def save_video(content):
        """
        将视频的二进制数据保存到本地
        """
        video_name = str(random.randint(100, 999)) + ".mp4"
        with open(video_name, 'wb') as f:
            f.write(content)
    
            
    # 获取首页源码
    page_text = requests.get(url=url, headers=headers).text
    
    tree = etree.HTML(page_text)
    li_list = tree.xpath('//ul[@class="listvideo-list clearfix"]/li')
    
    video_url_list = list()
    for li in li_list:
        detail_url = "https://www.pearvideo.com/" + li.xpath('./div/a/@href')[0]
        
        # 获取该视频页面的源码
        detail_page_text = requests.get(url=detail_url, headers=headers).text
        
        # 正则匹配视频的URL
        video_url = re.findall(ex, detail_page_text, re.S)[0]
        video_url_list.append(video_url)
        
    pool = Pool(4)
        
    #使用线程池将视频的二进制数据下载下来
    content_list = pool.map(request_video, video_url_list)
        
    # 使用线程池将视频的二进制数据保存到本地
    pool.map(save_video, content_list)    
    
    print("执行耗时: ", time.time() - start_time)
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  • 原文地址:https://www.cnblogs.com/youhongliang/p/12708250.html
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