• 豆瓣top250(go版以及python版)


      最近学习go,就找了一个例子练习【go语言爬虫】go语言爬取豆瓣电影top250,思路大概就是获取网页,然后根据页面元素,用正则表达式匹配电影名称、评分、评论人数。原文有个地方需要修改下pattern4 := <img width="100" alt="(.*?)" src=,这样就能运行了结果截图
    这个例子可以由修改下变成并发的形式,提高性能(参考golang 并发 chan

    var sem chan int = make(chan int,10);
       for i := 0; i < 10; i++ {
       	go func(i int) {
       		header := map[string]string{
       			"Host":                      "movie.douban.com",
       			"Connection":                "keep-alive",
       			"Cache-Control":             "max-age=0",
       			"Upgrade-Insecure-Requests": "1",
       			"User-Agent":                "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/53.0.2785.143 Safari/537.36",
       			"Accept":                    "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8",
       			"Referer":                   "https://movie.douban.com/top250",
       		}
       		fmt.Println("正在抓取第" + strconv.Itoa(i) + "页......")
       		url := "https://movie.douban.com/top250?start=" + strconv.Itoa(i*25) + "&filter="
       		spider := &Spider{url, header}
       		html := spider.get_html_header()
       		
       		pattern2 := `<span>(.*?)评价</span>`
       		rp2 := regexp.MustCompile(pattern2)
       		find_txt2 := rp2.FindAllStringSubmatch(html, -1)
       		
       		pattern3 := `property="v:average">(.*?)</span>`
       		rp3 := regexp.MustCompile(pattern3)
       		find_txt3 := rp3.FindAllStringSubmatch(html, -1)
    
       		
       		pattern4 := `<img width="100" alt="(.*?)" src=`
       		rp4 := regexp.MustCompile(pattern4)
       		find_txt4 := rp4.FindAllStringSubmatch(html, -1)
    
       		for i := 0; i < len(find_txt2); i++ {
       			fmt.Printf("%s %s %s
    ", find_txt4[i][1], find_txt3[i][1], find_txt2[i][1], )
       			f.WriteString(find_txt4[i][1] + "	" + find_txt3[i][1] + "	" + find_txt2[i][1] + "	" + "
    ")
    
       		}
       		sem <- 0
       	}(i)
       }
       for i := 0; i < 10; i++ { <-sem }
       close(sem)
    

    并发效果截图
      到这里go爬虫部分已经介绍完毕,百无聊赖之际又写了一个python版,python很简洁

    # coding=utf-8  #
    import re
    import urllib2
    import datetime
    def getDouban(i):
        print "爬取第" + str(i)+"页"
        html = "https://movie.douban.com/top250?start=" + str(i) + "&filter="
        try:
            page = urllib2.urlopen(html, timeout=3)
            result = page.read()
            score = re.findall('property="v:average">(.*?)</span>',result)
            person = re.findall('<span>(.*?)评价</span>',result)
            name= re.findall('<img width="100" alt="(.*?)" src=', result)
            j=0
            while j<len(name):
                print name[j], score[j]+'分', person[j]
                j=j+1
        except:
            print i
    starttime = datetime.datetime.now()
    params=[]
    for i in range(25):
        getDouban(i)
    endtime = datetime.datetime.now()
    print "爬虫历时"+str((endtime-starttime).seconds)+"s完成"
    

    python版运行结果

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  • 原文地址:https://www.cnblogs.com/polong/p/9831244.html
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