import requests, os, time
import aiohttp, asyncio
import hashlib


class Spider(object):

    def __init__(self):
        self.headers = {
            'User-Agent':''}
        self.num = 1
        if 'pro' not in os.listdir('.'):
            os.mkdir('pro')
        self.path = os.path.join(os.path.abspath('.'),'pro')
        os.chdir(self.path)# 进入文件下载路径

    async def __get_content(self, link): # 传入的是图片链接
        async with aiohttp.ClientSession() as session:
            response =await session.get(link)
            content = await response.read()
            return content

    def __get_img_links(self, page): # 获取图片链接
        # 使用requests请求返回全部图片的链接，也就是一个列表
        return 1,2 # 
    
    def __get_md5_path_name(self,url_name): # 把图片的URL传入进去,加密得到的字符串来做图片名称
        cre_md5 = hashlib.md5() 
        utf_url_name = url_name.encode(encoding = 'utf-8')
        cre_md5.update(utf_url_name)
        return cre_md5.hexdigest()
        

    async def __download_img(self, img):
        content = await self.__get_content(img) # 获取图片的进制文件
        file_name = self.__get_md5_path_name(img) # 获取到MD5名称
        
        with open(file_name + '.jpg', 'wb') as f:
            f.write(content)
        print('下载第%s张图片成功' % self.num)
        self.num +=1


    def run(self):
        start = time.time()
        for x in range(1,101): # 下载一百页的图片就可以了，或者自己更改页数
            links = self.__get_img_links(x) # 把那一页需要爬图片的链接传进去
            tasks = [asyncio.ensure_future(self.__download_img(link)) for link in links]
            loop = asyncio.get_event_loop()
            loop.run_until_complete(asyncio.wait(tasks))
            if self.num >= 10:# 测试速度使用，如需要下载多张图片可以注释这段代码
                break
            end = time.time()
            print('共运行了%s秒'% (end - start))

def main():
    spider = Spider()
    spider.run()

if __name__ == '__main__':
    main()