python爬虫headers设置后无效的解决方法

此次遇到的是一个函数使用不熟练造成的问题，但有了分析工具后可以很快定位到问题（此处推荐一个非常棒的抓包工具fiddler） 

正文如下：

在爬取某个app数据时（app上的数据都是由http请求的），用Fidder分析了请求信息，并把python的request header信息写在程序中进行请求数据

代码如下

import requestsurl = 'http://xxx?startDate=2017-10-19&endDate=2017-10-19&pageIndex=1&limit=50&sort=datetime&order=desc'headers={ "Host":"xxx.com", "Connection": "keep-alive", "Accept": "application/json, text/javascript, */*; q=0.01", "User-Agent": "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/29.0.1547.59 Safari/537.36", "X-Requested-With": "XMLHttpRequest", "Referer": "http://app.jg.eastmoney.com/html_Report/index.html", "Accept-Encoding": "gzip,deflate", "Accept-Language": "en-us,en", "Cookie":"xxx"}r = requests.get(url,headers)print (r.text)

请求成功但是，返回的是

{"Id":"6202c187-2fad-46e8-b4c6-b72ac8de0142","ReturnMsg":"加载失败！"}

就是被发现不是正常请求被拦截了

然后我去Fidder中看刚才python发送请求的记录 #盖掉的两个部分分别是Host和URL。

然后查看请求详细信息的时候，请求头并没有加载进去，User-Agent就写着python-requests !   #请求头里的UA信息是java，python程序，有点反爬虫意识的网站、app都会拦截掉

Header详细信息如下

GET http://xxx?istartDate=2017-10-19&endDate=2017-10-19&pageIndex=1&limit=50&sort=datetime&order=desc　　&Host=xxx.com　　&Connection=keep-alive　　&Accept=application%2Fjson%2C+text%2Fjavascript%2C+%2A%2F%2A%3B+q%3D0.01　　&User-Agent=Mozilla%2F5.0+%28Windows+NT+6.1%3B+WOW64%29+AppleWebKit%2F537.36+%28KHTML%2C+like+Gecko%29+Chrome%2F29.0.1547.59+Safari%2F537.36　　&X-Requested-With=XMLHttpRequest　　&Referer=xxx　　&Accept-Encoding=gzip%2Cdeflate　　&Accept-Language=en-us%2Cen　　&Cookie=xxxHTTP/1.1Host: xxx.comUser-Agent: python-requests/2.18.4Accept-Encoding: gzip, deflateAccept: */*Connection: keep-aliveHTTP/1.1 200 OKServer: nginx/1.2.2Date: Sat, 21 Oct 2017 06:07:21 GMTContent-Type: application/json; charset=utf-8Content-Length: 75Connection: keep-aliveCache-Control: privateX-AspNetMvc-Version: 5.2X-AspNet-Version: 4.0.30319X-Powered-By: ASP.NET

一开始还没发现，等我把请求的URL信息全部读完，才发现程序把我的请求头信息当做参数放到了URL里

那就是我请求的时候request函数Header信息参数用错了

又重新看了一下Requests库的Headers参数使用方法，发现有一行代码写错了，在使用request.get（）方法时要把参数 “headers =“写出来 

更改如下：

import requestsurl = 'http://xxx?startDate=2017-10-19&endDate=2017-10-19&pageIndex=1&limit=50&sort=datetime&order=desc'headers={ "Host":"xxx.com", "Connection": "keep-alive", "Accept": "application/json, text/javascript, */*; q=0.01", "User-Agent": "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/29.0.1547.59 Safari/537.36", "X-Requested-With": "XMLHttpRequest", "Referer": "http://app.jg.eastmoney.com/html_Report/index.html", "Accept-Encoding": "gzip,deflate", "Accept-Language": "en-us,en", "Cookie":"xxx"}r = requests.get(url,headers=headers)