tornado curl_httpclient proxy

tornado httpclient

默认simple_httpclient，满足大部分普通需求.

curl_httpclient更多特性(需要libcurl pycurl)：

• 支持http proxy,以及使用指定网络接口

• 不死磕http规范，兼容更多站点

• 效率更高

curl_httpclient 使用proxy实例

以下代码执行的机器通过代理访问网络

>>> import tornado
>>> tornado.version
'4.2.1'
>>> from tornado.httpclient import HTTPClient
>>> from tornado.httpserver import HTTPRequest
>>> c = HTTPClient()
>>> req = HTTPRequest(url="http://t.cp31.ott.cibntv.net/XXXX", follow_redirects=False, proxy_host="10.103.11.11", proxy_port=81)
>>> c.fetch(req)
Traceback (most recent call last):
  File "", line 1, in 
  File "/opt/python2.7/lib/python2.7/site-packages/tornado-4.2.1-py2.7-linux-x86_64.egg/tornado/httpclient.py", line 102, in fetch
    self._async_client.fetch, request, **kwargs))
  File "/opt/python2.7/lib/python2.7/site-packages/tornado-4.2.1-py2.7-linux-x86_64.egg/tornado/ioloop.py", line 445, in run_sync
    return future_cell[0].result()
  File "/opt/python2.7/lib/python2.7/site-packages/tornado-4.2.1-py2.7-linux-x86_64.egg/tornado/concurrent.py", line 215, in result
    raise_exc_info(self._exc_info)
  File "", line 3, in raise_exc_info
tornado.httpclient.HTTPError: HTTP 599: Timeout

#simple_httpclient 不支持代理,599超时

>>> from tornado.curl_httpclient import CurlAsyncHTTPClient
>>> from tornado.ioloop import IOLoop
>>> c = CurlAsyncHTTPClient()
>>> def print_response(r):
...     print r.error or r.body
... 
>>> c.fetch(req, print_response)
>>> IOLoop.instance().start()
HTTP 301: Moved Permanently
ERROR:tornado.application:Future exception was never retrieved: HTTPError: HTTP 301: Moved Permanently

# curl_httpclient使用代理成功联网，取得该URL的301信息

所以有童鞋说curl可以访问某个URL,证明网络通畅,就是tornado代码无法访问该URL，大概原因就是如此了.调试步骤

• curl 能访问,说明网络通畅(不论是否有走代理)

• urllib2确认一下Python代码能访问，如果urllib2都能访问，tornado不行，那极大概率是上面所述

• tornado换curl_httpclient