Python爬取网页图片03

#!/usr/bin/env python2.7
# coding:utf-8

import re,sys,urllib,requests,os

def get_onepage_urls(onepageurl):
    '''
    获取当前页面所有图片的url 和 下一页的url
    '''
    if not onepageurl:
        print '已经是最后一页！'
        return [],''
    try:
        html = requests.get(onepageurl).text
    except Exception as e:
        print e
        pic_urls = []
        next_url = ''
        return pic_urls,next_url
    pic_urls = re.findall('"objURL":"(.*?)",', html, re.S)

    next_urls = re.findall(re.compile(r'<a href="(.*)" class="n">下一页</a>'), html, flags=0)
    next_url = 'http://image.baidu.com' + next_urls[0] if next_urls else ''
    return pic_urls,next_url      

def down_pic(pic_urls):
    '''
    通过图片链接列表，下载所有的图片
    '''
    path="images"
    if(os.path.exists(path)==False):
        os.makedirs(path)
    for i,pic_url in enumerate(pic_urls):
        try:
            pic = requests.get(pic_url,timeout = 15)
            string =path+"/"+str(i + 1) + '.jpg'
            with open(string,'wb') as f:
                f.write(pic.content)
                print '成功下载第  %s 张图片 ：%s' % (str(i+1),str(pic_url))
        except Exception as e:
            print '下载第  %s 张图片时失败：%s' % (str(i+1),str(pic_url))
            print e
            continue
if __name__ == '__main__':
    keyword = '蓝天' #你想输入的关键词
    url_init_first = r'http://image.baidu.com/search/flip?tn=baiduimage&ipn=r&ct=201326592&cl=2&lm=-1&st=-1&fm=result&fr=&sf=1&fmq=1497491098685_R&pv=&ic=0&nc=1&z=&se=1&showtab=0&fb=0&width=&height=&face=0&istype=2&ie=utf-8&word= '
    url_init = url_init_first + urllib.quote(keyword,safe='/')
    all_pic_urls = []
    onepage_urls,next_url = get_onepage_urls(url_init)
    all_pic_urls.extend(onepage_urls)

    next_count = 0 #初始化翻页数
    while 1:
        onepage_urls,next_url = get_onepage_urls(next_url)
        next_count += 1
        print '第  %s页' % next_count
        if next_url == '' and onepage_urls == []:
            break
        all_pic_urls.extend(onepage_urls)
    down_pic(list(set(all_pic_urls)))