Python爬虫之路——简单网页抓图升级版（增加多线程支持）

经过两个晚上的奋斗，将上一篇文章介绍的爬虫稍微改进了下（Python爬虫之路——简单网页抓图），主要是将获取图片链接任务和下载图片任务用线程分开来处理了，而且这次的爬虫不仅仅可以爬第一页的图片链接的，整个http://desk.zol.com.cn/meinv/下面的图片都会被爬到，而且提供了多种分辨率图片的文件下载，具体设置方法代码注释里面有介绍。

这次的代码仍然有点不足，Ctrl-C无法终止程序，应该是线程无法响应主程序的终止消息导致的，（最好放在后台跑程序）还有线程的分配还可以优化的更好一点，后续会陆续改进.

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#coding: utf-8 #############################################################

# File Name: main.py

# Author: mylonly

# mail: mylonly@gmail.com

# Created Time: Wed 11 Jun 2014 08:22:12 PM CST

#########################################################################

#!/usr/bin/python

import re,urllib2,HTMLParser,threading,Queue,time

#各图集入口链接

htmlDoorList = []

#包含图片的Hmtl链接

htmlUrlList = []

#图片Url链接Queue

imageUrlList = Queue.Queue(0)

#捕获图片数量

imageGetCount = 0

#已下载图片数量

imageDownloadCount = 0

#每个图集的起始地址，用于判断终止

nextHtmlUrl = ''

#本地保存路径

localSavePath = '/data/1920x1080/'

#如果你想下你需要的分辨率的，请修改replace_str,有如下分辨率可供选择1920x1200，1980x1920,1680x1050,1600x900,1440x900,1366x768,1280x1024,1024x768,1280x800

replace_str = '1920x1080'

replaced_str = '960x600'

#内页分析处理类

class ImageHtmlParser(HTMLParser.HTMLParser):

def __init__(self):

self.nextUrl = ''

HTMLParser.HTMLParser.__init__(self)

def handle_starttag(self,tag,attrs):

global imageUrlList

if(tag == 'img' and len(attrs) > 2 ):

if(attrs[0] == ('id','bigImg')):

url = attrs[1][1]

url = url.replace(replaced_str,replace_str)

imageUrlList.put(url)

global imageGetCount

imageGetCount = imageGetCount + 1

print url

elif(tag == 'a' and len(attrs) == 4):

if(attrs[0] == ('id','pageNext') and attrs[1] == ('class','next')):

global nextHtmlUrl

nextHtmlUrl = attrs[2][1];

#首页分析类

class IndexHtmlParser(HTMLParser.HTMLParser):

def __init__(self):

self.urlList = []

self.index = 0

self.nextUrl = ''

self.tagList = ['li','a']

self.classList = ['photo-list-padding','pic']

HTMLParser.HTMLParser.__init__(self)

def handle_starttag(self,tag,attrs):

if(tag == self.tagList[self.index]):

for attr in attrs:

if (attr[1] == self.classList[self.index]):

if(self.index == 0):

#第一层找到了

self.index = 1

else:

#第二层找到了

self.index = 0

print attrs[1][1]

self.urlList.append(attrs[1][1])

break

elif(tag == 'a'):

for attr in attrs:

if (attr[0] == 'id' and attr[1] == 'pageNext'):

self.nextUrl = attrs[1][1]

print 'nextUrl:',self.nextUrl

break

#首页Hmtl解析器

indexParser = IndexHtmlParser()

#内页Html解析器

imageParser = ImageHtmlParser()

#根据首页得到所有入口链接

print '开始扫描首页...'

host = 'http://desk.zol.com.cn'

indexUrl = '/meinv/'

while (indexUrl != ''):

print '正在抓取网页:',host+indexUrl

request = urllib2.Request(host+indexUrl)

try:

m = urllib2.urlopen(request)

con = m.read()

indexParser.feed(con)

if (indexUrl == indexParser.nextUrl):

break

else:

indexUrl = indexParser.nextUrl

except urllib2.URLError,e:

print e.reason

print '首页扫描完成，所有图集链接已获得：'

htmlDoorList = indexParser.urlList

#根据入口链接得到所有图片的url

class getImageUrl(threading.Thread):

def __init__(self):

threading.Thread.__init__(self)

def run(self):

for door in htmlDoorList:

print '开始获取图片地址,入口地址为:',door

global nextHtmlUrl

nextHtmlUrl = ''

while(door != ''):

print '开始从网页%s获取图片...'% (host+door)

if(nextHtmlUrl != ''):

request = urllib2.Request(host+nextHtmlUrl)

else:

request = urllib2.Request(host+door)

try:

m = urllib2.urlopen(request)

con = m.read()

imageParser.feed(con)

print '下一个页面地址为:',nextHtmlUrl

if(door == nextHtmlUrl):

break

except urllib2.URLError,e:

print e.reason

print '所有图片地址均已获得:',imageUrlList

class getImage(threading.Thread):

def __init__(self):

threading.Thread.__init__(self)

def run(self):

global imageUrlList

print '开始下载图片...'

while(True):

print '目前捕获图片数量:',imageGetCount

print '已下载图片数量:',imageDownloadCount

image = imageUrlList.get()

print '下载文件路径:',image

try:

cont = urllib2.urlopen(image).read()

patter = '[0-9]*\.jpg';

match = re.search(patter,image);

if match:

print '正在下载文件：',match.group()

filename = localSavePath+match.group()

f = open(filename,'wb')

f.write(cont)

f.close()

global imageDownloadCount

imageDownloadCount = imageDownloadCount + 1

else:

print 'no match'

if(imageUrlList.empty()):

break

except urllib2.URLError,e:

print e.reason

print '文件全部下载完成...'

get = getImageUrl()

get.start()

print '获取图片链接线程启动:'

time.sleep(2)

download = getImage()

download.start()

print '下载图片链接线程启动:'