python: HTTP connections through a proxy server requiring authentication

[sajuptpm]

Hi,

I followed http://dabase.com/blog/Minimal_squid3_proxy_configuration/ to setup proxy server.
I tested my proxy server with firefox with IP:127.0.0.1 and Port:3128 and it working (asking for proxy username and password).

But, i could not make http connection through proxy server requiring authentication using following python code..

########## Python code ########## 

import urllib2
proxy = urllib2.ProxyHandler({'http':'http://saju:123@saju-Inspiron-N5010:3128'})
opener = urllib2.build_opener(proxy, urllib2.HTTPHandler)
urllib2.install_opener(opener)

conn = urllib2.urlopen('http://python.org')
return_str = conn.read()
print "===return_st====", return_str


==== ERROR ====

Traceback (most recent call last):
  File "my_proxy.py", line 6, in <module>
    conn = urllib2.urlopen('http://python.org')
  File "/usr/lib/python2.7/urllib2.py", line 127, in urlopen
    return _opener.open(url, data, timeout)
  File "/usr/lib/python2.7/urllib2.py", line 407, in open
    response = meth(req, response)
  File "/usr/lib/python2.7/urllib2.py", line 520, in http_response
    'http', request, response, code, msg, hdrs)
  File "/usr/lib/python2.7/urllib2.py", line 445, in error
    return self._call_chain(*args)
  File "/usr/lib/python2.7/urllib2.py", line 379, in _call_chain
    result = func(*args)
  File "/usr/lib/python2.7/urllib2.py", line 528, in http_error_default
    raise HTTPError(req.get_full_url(), code, msg, hdrs, fp)
urllib2.HTTPError: HTTP Error 407: Proxy Authentication Required



########## Proxy Server Settings ########## 

sudo vim /etc/squid3/squid.conf
-------------------------------
auth_param digest program /usr/lib/squid3/digest_pw_auth -c /etc/squid3/passwords
auth_param digest realm saju-Inspiron-N5010
acl authenticated proxy_auth REQUIRED
http_access allow authenticated
http_port 3128

Setting up user
--------------

htdigest -c /etc/squid3/passwords saju-Inspiron-N5010 saju

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