Python 写的图片蜘蛛人

    原文地址：http://www.darkbull.net/python/bd/%E5%86%99%E4%B8%AA%E5%9B%BE%E7%89%87%E8%9C%98%E8%9B%9B%E7%8E%A9%E7%8E%A9/

    写了个图片蜘蛛人玩玩，抓了几个网页试试，感觉不不错。核心的代码可能20行也不到，简洁明了，嘻嘻。废话少说，翠花，上代码~~

#coding=utf-8

import os
import sys
import re
import urllib

URL_REG = re.compile(r'(http://[^///]+)', re.I)
IMG_REG = re.compile(r'<img[^>]*?src=([/'"])([^/1]*?)/1', re.I)

def download(dir, url):
    '''下载网页中的图片
    
    @dir 保存到本地的路径
    @url 网页url
'''
    global URL_REG, IMG_REG
    
    m = URL_REG.match(url)
    if not m: 
        print '[Error]Invalid URL: ', url
        return
    host = m.group(1)
    
    if not os.path.isdir(dir):
        os.mkdir(dir)
    
    # 获取html,提取图片url
    html = urllib.urlopen(url).read()
    imgs = [item[1].lower() for item in IMG_REG.findall(html)]
    f = lambda path: path if path.startswith('http://') else /
                host + path if path.startswith('/') else url + '/' + path
    imgs = list(set(map(f, imgs)))
    print '[Info]Find %d images.' % len(imgs)
    
    # 下载图片
    for idx, img in enumerate(imgs):
        name = img.split('/')[-1]
        path = os.path.join(dir, name)
        try: 
            print '[Info]Download(%d): %s'% (idx + 1, img)
            urllib.urlretrieve(img, path)
        except: 
            print "[Error]Cant't download(%d): %s" % (idx + 1, img)
    
def main():
    if len(sys.argv) != 3:
        print 'Invalid argument count.'
        return
    dir, url = sys.argv[1:]
    download(dir, url)

if __name__ == '__main__':
    # download('D://Imgs', 'http://www.163.com')
    main()