HTTP basic authentication using sockets in python

Question

How to connect to a server using basic http auth thru sockets in python .I don't want to use urllib/urllib2 etc as my program does some low level socket I/O operations

Answer 1

Probably the easiest place to start is using makefile() to get a simpler file-like interface to the socket.

import socket, base64

host= 'www.example.com'
path= '/'
username= 'fred'
password= 'bloggs'
token= base64.encodestring('%s:%s' % (username, password)).strip()

lines= [
    'GET %s HTTP/1.1' % path,
    'Host: %s' % host,
    'Authorization: Basic %s' % token,
    'Connection: close',
]

s= socket.socket()
s.connect((host, 80))
f= s.makefile('rwb', bufsize=0)
f.write('\r\n'.join(lines)+'\r\n\r\n')
response= f.read()
f.close()
s.close()

You'll have to do a lot more work than that if you need to interpret the returned response to pick out the HTML or auth-required headers, and handle redirects, errors, transfer-encoding and all that right. HTTP can be complex! Are you sure you need to use a low-level socket?

Answer 2

Look e.g. at urllib's sources, specifically the http_error_401 function (and the dispatching around it of course): make the HTTP request, watch for a 401 response, extract its realm, check that its scheme is basic, try again with the user and password for that realm (cfr function retry_http_basic_auth in that same source file). Lots of work of course, but that's the price of programming "down to the bare metal" as you require.