Thanks, Laurens. I will have a try with your advices.

Message: 2
Date: Thu, 21 Mar 2013 07:32:18 -0700
From: Laurens Van Houtven <_@lvh.cc>
Subject: Re: [Twisted-web] A Question, TIA!
To: Twisted Web World <twisted-web@twistedmatrix.com>
Message-ID:
<CAE_Hg6YN8-cf42=ddPSW2w6zJ08-R+9z=+9G0q2EHOXYyMSRdQ@mail.gmail.com>
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Sounds like you want twisted.web.client.Agent;  when you make a request you
get an IResponse object that has a deliverBody method that takes a
protocol. That protocol can receive chunks (dataReceived), or you could use
e.g. a LineReceiver if you know they're delimited chunks.