POST抓取页面的问题_html/css_WEB-ITnose

某同学反映，spider通过post方式抓取某站点有问题，老是302到自己，具体如下：

url ：http://www.meituan.com/multiact/default/deal/25814805.html

post数据："yui_3_16_0_1_1423700000_000:{\"act\":\"deal/dynamiccomponent\",\"args\":25814805,\"__referer\":\"\"}"

通过python可以正常抓取，抓取代码如下：

import urllibimport urllib2values = {        'yui_3_16_0_1_1423700000_000':'{"act":"deal/dynamiccomponent","args":25814805,"__referer":""}',}header={        "X-Requested-With":"XMLHttpRequest",}url="http://www.meituan.com/multiact/default/deal/25814805.html"data = urllib.urlencode(values)print datareq = urllib2.Request(url, data,header)response = urllib2.urlopen(req)the_page = response.read()print the_page

但是自己构造http请求包无法抓取，请求包如下：
POST /multiact/default/deal/25814805.html HTTP/1.1^M
Host: www.meituan.com^M
Content-Length: 126^M
Connection: close^M
Content-Type: application/x-www-form-urlencoded^M
User-Agent: Mozilla/5.0 (Windows NT 5.1; rv:6.0.2) Gecko/20100101 Firefox/6.0.2^M
Accept-Encoding: gzip^M
Accept: */*^M
X-Requested-With: XMLHttpRequest^M

抓取失败原因，缺少该参数：Content-Type: application/x-www-form-urlencoded^M

加上就可以了，具体如下：

POST /multiact/default/deal/25814805.html HTTP/1.1^M
Host: www.meituan.com^M
Content-Length: 126^M
Connection: close^M
Content-Type: application/x-www-form-urlencoded^M
User-Agent: Mozilla/5.0 (Windows NT 5.1; rv:6.0.2) Gecko/20100101 Firefox/6.0.2^M
Accept-Encoding: gzip^M
Accept: */*^M
X-Requested-With: XMLHttpRequest^M

Content-Type: application/x-www-form-urlencoded^M