• python笔记13-多线程实战篇(tomorrow)


    安装

    1.tomorrow安装,用pip可以直接安装

    pip install tomorrow

    单线程

    1。以下案例是单线程时候跑的情况,在下载图片的时候很耗时。

    # coding:utf-8
    from bs4 import BeautifulSoup
    import requests
    import os
    import time
    
    # 当前脚本所在的目录
    cur_path = os.path.dirname(os.path.realpath(__file__))
    
    
    def get_img_urls():
        r = requests.get("http://699pic.com/sousuo-218808-13-1.html")
        fengjing = r.content
        soup = BeautifulSoup(fengjing, "html.parser")
        # 找出所有的标签
        images = soup.find_all(class_="lazy")
        return images
    
    def save_img(imgUrl):
        try:
            jpg_rl = imgUrl["data-original"]
            title = imgUrl["title"]
            # print(title)
            # print(jpg_rl)
            # print("")
            # 判断是否有jpg文件夹,不存在创建一个
            save_file = os.path.join(cur_path, "jpg")
            if not os.path.exists(save_file): os.makedirs(save_file)
    
            with open(os.path.join(save_file, title+'.jpg'), "wb") as f:
                f.write(requests.get(jpg_rl).content)
        except:
            pass
    
    if __name__ == "__main__":
        t1 = time.time()
    
        image_ulrs = get_img_urls()
        for i in image_ulrs:
            save_img(i)
    
        t2 = time.time()
        print("总耗时:%.2f 秒"%(t2-t1))

    运行结果:

    耗时:4.27 秒

    使用多线程tomorrow

    1.一行代码搞定多线程,在函数上加个@threads(5),括号里面代码线程的数量,数字越大,运行的速度越快

    # coding:utf-8
    from bs4 import BeautifulSoup
    import requests
    import os
    import time
    from tomorrow import threads
    
    # 当前脚本所在的目录
    cur_path = os.path.dirname(os.path.realpath(__file__))
    
    
    def get_img_urls():
        r = requests.get("http://699pic.com/sousuo-218808-13-1.html")
        fengjing = r.content
        soup = BeautifulSoup(fengjing, "html.parser")
        # 找出所有的标签
        images = soup.find_all(class_="lazy")
        return images
    
    @threads(5)
    def save_img(imgUrl):
        try:
            jpg_rl = imgUrl["data-original"]
            title = imgUrl["title"]
            # print(title)
            # print(jpg_rl)
            # print("")
            # 判断是否有jpg文件夹,不存在创建一个
            save_file = os.path.join(cur_path, "jpg")
            if not os.path.exists(save_file): os.makedirs(save_file)
    
            with open(os.path.join(save_file, title+'.jpg'), "wb") as f:
                f.write(requests.get(jpg_rl).content)
        except:
            pass
    
    if __name__ == "__main__":
        t1 = time.time()
    
    
        image_ulrs = get_img_urls()
        for i in image_ulrs:
            save_img(i)
    
        t2 = time.time()
        print("总耗时:%.2f 秒"%(t2-t1))

    运行结果:

    总耗时:0.24 秒
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  • 原文地址:https://www.cnblogs.com/mashuqi/p/10412039.html
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