WinGate Product Question - Need guidance

[spalmer]

I'm going to say this up front so that there is no misunderstanding: I do not know much about proxy server software, but I have to find a product that will do two very specific things. I'm being fed requirements from developers. I hope what I'm about to ask will make sense.

We need a proxy server to do testing for our web-based product. The proxy server must be able to do two things:

1) Make back-to-back, "double" requests for certain ASP pages. For example, it needs to be able to request an ASP page twice in a row, once for the purposes of caching the file and once for delivery to the client browser. Here is a SANITIZED copy of the IIS logs showing this in action in the real world:

2007-02-05 16:17:06 W3SVC1 SERVERNAME [IP ADDRESS] GET /roadshows.asp - 80 - [IP ADDRESS} HTTP/1.0 Mozilla/4.0+(compatible;+MSIE+6.0;+Windows+NT+5.1;+.NET+CLR+1.1.4322;+InfoPath.1;+.NET+CLR+2.0.50727) flashVer=7;+bwc=0;+ASPSESSIONIDSARQAASA=NMOFJDPCFMFKFFJOLLNHHPOF - http://www.domainname.com 200 0 0 16633 534 281
2007-02-05 16:17:18 W3SVC1 SERVERNAME [IP ADDRESS] GET /sys/loader.asp qv=62387&i=391 80 - [IP ADDRESS] HTTP/1.0 Mozilla/4.0+(compatible;+MSIE+6.0;+Windows+NT+5.1;+.NET+CLR+1.1.4322;+InfoPath.1;+.NET+CLR+2.0.50727) flashVer=7;+bwc=0;+ASPSESSIONIDSARQAASA=NMOFJDPCFMFKFFJOLLNHHPOF;+cookies=true http://www.domainname.com/roadshows.asp http://www.domainname.com 200 0 0 435 618 249
2007-02-05 16:17:18 W3SVC1 SERVERNAME [IP ADDRESS] GET /sys/launch.asp qv=7035965006835045&k=83786888886 80 - [IP ADDRESS] HTTP/1.0 Mozilla/4.0+(compatible;+MSIE+6.0;+Windows+NT+5.1;+.NET+CLR+1.1.4322;+InfoPath.1;+.NET+CLR+2.0.50727) flashVer=7;+bwc=0;+ASPSESSIONIDSARQAASA=NMOFJDPCFMFKFFJOLLNHHPOF;+cookies=true - http://www.domainname.com 200 0 0 2555 583 140
2007-02-05 16:17:18 W3SVC1 SERVERNAME [IP ADDRESS] GET /platform/roadshow/wrapper_106.asp qv=88350&k=83786888886&c=%2Fconsoles%2Fstandard%2Froadshow%5F106%2Eswf 80 - [IP ADDRESS] HTTP/1.1 Mozilla/4.0+(compatible;+MSIE+6.0;+Windows+NT+5.1;+.NET+CLR+1.1.4322;+InfoPath.1;+.NET+CLR+2.0.50727) flashVer=7;+bwc=0;+ASPSESSIONIDSARQAASA=NMOFJDPCFMFKFFJOLLNHHPOF;+cookies=true http://www.domainname.com/sys/launch.as ... 3786888886 http://www.domainname.com 200 0 0 5177 770 156
2007-02-05 16:17:18 W3SVC1 SERVERNAME [IP ADDRESS] GET /sys/logdb.asp qv=55643&m=p&k=83786888886 80 - [IP ADDRESS] HTTP/1.1 Mozilla/4.0+(compatible;+MSIE+6.0;+Windows+NT+5.1;+.NET+CLR+1.1.4322;+InfoPath.1;+.NET+CLR+2.0.50727) flashVer=7;+bwc=0;+ASPSESSIONIDSARQAASA=NMOFJDPCFMFKFFJOLLNHHPOF;+cookies=true http://www.[IP ADDRESS].com/sys/launch.asp?qv=7035965006835045&k=83786888886 http://www.domainname.com 200 0 0 324 706 312
2007-02-05 16:17:18 W3SVC1 SERVERNAME [IP ADDRESS] GET /sys/wrapperInc.asp qv=15175&k=83786888886 80 - [IP ADDRESS] HTTP/1.1 Mozilla/4.0+(compatible;) - - http://www.domainname.com 200 0 0 396 280 156
2007-02-05 16:17:18 W3SVC1 SERVERNAME [IP ADDRESS] GET /sys/wrapperInc.asp qv=15175&k=83786888886 80 - [IP ADDRESS] HTTP/1.0 Mozilla/4.0+(compatible;+MSIE+6.0;+Windows+NT+5.1;+.NET+CLR+1.1.4322;+InfoPath.1;+.NET+CLR+2.0.50727) flashVer=7;+bwc=0;+ASPSESSIONIDSARQAASA=NMOFJDPCFMFKFFJOLLNHHPOF;+cookies=true http://www.domainname.com/platform/road ... F106%2Eswf http://www.domainname.com 200 0 0 354 560 203
2007-02-05 16:17:20 W3SVC1 SERVERNAME [IP ADDRESS] GET /sys/getData.asp id=31519968344 80 - [IP ADDRESS] HTTP/1.0 Mozilla/4.0+(compatible;+MSIE+6.0;+Windows+NT+5.1;+.NET+CLR+1.1.4322;+InfoPath.1;+.NET+CLR+2.0.50727) flashVer=7;+bwc=0;+ASPSESSIONIDSARQAASA=NMOFJDPCFMFKFFJOLLNHHPOF;+cookies=true - http://www.domainname.com 200 0 0 345 407 296

Notice how back-to-back requests are made by the proxy server for /sys/wrapperInc.asp. One of these requests is passed through by the proxy server to our server with all ASP session cookie headers intact. The other doesn't have the ASP session cookie headers, indicating that it is simply the proxy server trying to cache the page.

2) Return the cached version of an ASP page that is the source of a <script> include tag. Here's an example of a line of code that causes this to happen for certain proxy servers.

<script language="javascript" src="/sys/wrapperInc.asp?qv=873643&k=50204735"></script>


Does anyone know if WinGate will do this? I would GREATLY appreciate some help.

[adrien]

Hi

I've never heard of a proxy doubling requests before. I'm curious as to why double the request simply for caching. All caching proxies I know of use the same request to satisfy the client request and also populate the cache. If you need a different request to populate the cache, that indicates to me there is some other design issue somewhere. E.g. it's incorrect for a proxy to arbitrarily strip headers to make a request to populate a cache, and then it would be incorrect for it to serve that cached entry based on an arbitrarily modified request.

So sorry, WinGate doesn't have the capability to do that. You could do it with maybe a PHP/CGI proxy.

[adrien]

WinGate 2008 could possibly achieve this using an external HTTP client.

You can trigger external actions on any request, so WinGate could spawn say wget.exe with the URL requested to get it to do the second request.

If you'd like to try this, let me know, we haven't released WinGate 2008 yet.

[spalmer]

WinGate 2008 could possibly achieve this using an external HTTP client.

You can trigger external actions on any request, so WinGate could spawn say wget.exe with the URL requested to get it to do the second request.

If you'd like to try this, let me know, we haven't released WinGate 2008 yet.

Is this a product that I could get a copy of for testing purposes?

[adrien]

definitely.

I'll email you a link. Please be aware it's pre-release code however, there are still a few issues, but it should show you if it will work in this way for you or not.

Regards

Adrien

[adrien]

as per phone call, glad to help get the request doubling working, let me know if you need any more help with that.

Note also, that if your devs need to, they can modify the request that goes through WinGate (using policy) and I think you can also set headers in the wget.exe request using command line options.

As for part 2 - I'm not sure what you mean by return the cached version of an ASP page etc.

Does this mean your server is getting a request for the script, and you need to return instead the ASP page that included it? But a cached version? Whose cached version is this, the client (browser) or some proxy?

I presume when a client makes a request for the script file that was included in the script tag, it sets the referer field in the request to the URL of the page that had the script tag in it. You could try looking at this, and use that to satisfy the request with a re-write. But the mechanism to get a client to use its cached copy of something doesn't allow you to redirect it anywhere - you have to send a status code 304 back.

I'd need to know more specifics about the setup and what you're trying to test with that one.