How to intercept GET requests and fake the responses

orbiter

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Jul 15, 2009, 4:43:17 AM7/15/09

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Hi,
I'm new to the whole firefox customization thing and the only thing
I've done so far is write some simple greasmonkey scripts to clean up
and simplify certain websites I constantly visit. Mainly removing ads
and posting links to my del.icio.us account with xmlHttpRequest. So
what I currently would like to do is intercept "useless" GET requests
fired by javascript scripts and fake the responses from my local
firefox session. I say "useless" because most of these requests are
used to modify the page after I visit it by pulling in ad information
and some other useless junk that is completely irrelevant to the
site's main function. I've looked into running a local filtering proxy
but if I can do it from within firefox then that would be preferable.
Appreciate any help you guys can provide.

Ralph Fox

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Jul 15, 2009, 5:17:01 AM7/15/09

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On Wed, 15 Jul 2009 01:43:17 -0700 (PDT), in message <f6f5aa19-4a58-437e...@h2g2000yqg.googlegroups.com>
orbiter <dkara...@gmail.com> wrote:

> X-HTTP-UserAgent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.1)
> Gecko/20090624 Firefox/3.5,gzip(gfe),gzip(gfe)

Write yourself a proxy.pac (proxy auto-config) script to catch the
unwanted URLs and point Firefox to a non-existent proxy for them.

Put the proxy.pac file somewhere on your hard drive. In Firefox for
Linux, go to "Edit � Preferences � Advanced � Network � Settings"
and enter the file:/// URL to the proxy.pac file in the box labelled
"Automatic proxy configuration URL".

More information: http://en.wikipedia.org/wiki/Proxy_auto-config

--
Regards
Ralph

orbiter

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Jul 15, 2009, 1:19:25 PM7/15/09

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On Jul 15, 2:17 am, Ralph Fox <-rf-...@-.invalid> wrote:
> On Wed, 15 Jul 2009 01:43:17 -0700 (PDT), in message <f6f5aa19-4a58-437e-817f-1087a8c2c...@h2g2000yqg.googlegroups.com>

This is a step in the right direction and with some extra plumbing I
think I could get it to do what I want. To be more specific I would
basically like a server with scripting capabilities that sits between
firefox and the target server I'm connecting to with firefox. In terms
of diagrams: firefox<--->programmable proxy<--->server. I not only
want to drop requests but I want to also modify the response so that
firefox and the site I'm currently on think the request was successful.

Ralph Fox

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Jul 16, 2009, 5:24:31 AM7/16/09

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1. If a "successful" response is sufficient by itself (you don't need
to return different content for different intercepted URLs), then
you could use a proxy.pac script to point the unwanted URLs to a
simple local proxy which returrns a (say) 1x1 transparent GIF image
to any request.

2. If not, maybe one of these could be useful

BFilter ........ http://bfilter.sourceforge.net/

Privoxy ........ http://www.privoxy.org/

Proxomitron .... http://www.sankey.ws/proxomitron.html

--
Regards
Ralph

orbiter

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Jul 16, 2009, 11:54:21 AM7/16/09

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On Jul 16, 2:24 am, Ralph Fox <-rf-...@-.invalid> wrote:
> On Wed, 15 Jul 2009 10:19:25 -0700 (PDT), in message <c20965fa-25b7-4a74-94db-2174d7275...@k1g2000yqf.googlegroups.com>

Privoxy did the trick, thanks.

orbiter

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Jul 16, 2009, 12:42:09 PM7/16/09

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On Jul 16, 2:24 am, Ralph Fox <-rf-...@-.invalid> wrote:
> On Wed, 15 Jul 2009 10:19:25 -0700 (PDT), in message <c20965fa-25b7-4a74-94db-2174d7275...@k1g2000yqf.googlegroups.com>

Privoxy did the trick, thanks.

orbiter

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Jul 16, 2009, 12:54:18 PM7/16/09

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On Jul 16, 2:24 am, Ralph Fox <-rf-...@-.invalid> wrote:
> On Wed, 15 Jul 2009 10:19:25 -0700 (PDT), in message <c20965fa-25b7-4a74-94db-2174d7275...@k1g2000yqf.googlegroups.com>

Privoxy did the trick, thanks.