HTTPModule not called for non-existant pages

[Guest]

I have earlier used an HttpModule that did URL rewrites on the BeginRequest
event.

Now I am trying to use the same module in a different application on a new
and upgraded machine (winxp sp2).

The Module is registered via Web.config. The registration is OK. When asking
for an existing .aspx page, the eventhandler is called as it should.

HOWEVER - if the request url is for a non-existant file, I get a 404 - file
not found error. The module is never called.
And if the url is only a path name e.g. http://server/some/path - and that
path does not allow browsing, then I get Directory Listing Denied error. If
browsing is allowed, I see the contents. The HttpModule BeginRequest method
is *not* called in these instances.

Any clues on what I may be missing here? or is this a change done through
sp2?

Thank you for your time!

-Inge

 

[Jeffrey Palermo [MCP]]

Inge,
To do some work based on the requested page whether or not it exists, do
the work using the AuthorizeRequest event. I use this event to do URL
rewriting. Of course, there are still some restrictions. If you have the
default page set to default.aspx, and there is no default.aspx, then the
ASP.NET ISAPI won't ever be called from IIS. If you have a default page,
IIS handles translating a request to /subFolder/ into
/subFolder/default.aspx. Then the requested resource ends in .aspx and the
ASP.NET ISAPI takes over and will execute you code, so a situation may still
exist where IIS never calls ASP.NET.

Best regards,
Jeffrey Palermo

 

[Guest]

Thank you for the reply.

If my memory is not failling me, I have had the handler be called for
nonexistant files, and also for folder names - without changing the default
document.

But what you say seems to be working - at least insofar as the HttpModule
being triggered when the request is for any kind of .aspx.

However, I have moved the default.aspx-file to the top of the
default-documents list (which *is* enabled). the handler is still not
executed if I only request http://myserver/mywebsite

If I put in a file of that name, it works (as expected) - but this requires
a default.aspx in every subfolder, in order to get the httpmodule to process
BeginRequest.

This is *not* the behaviour I experienced this spring :/

So I am still wondering that something might have changed e.g. with the
introduction of WinXP sp2

-Inge

 

[Guest]

After looking at the behaviour of the old system running the code, the
behaviour is definitely different.

MSFT, can you look into this - it seems that there is a change in how
HttpModules are processed.

Old behaviour (WinXP, and W2K server w/IIS 5.0):
-registered an httpmodule in web.config
-the module implements BeginRequest
-the module rewrites any folder-only URLs (i.e. ending in / or without
an extension) to somepage.aspx
-default page for the virtual directory is (probably) set to
default.aspx

If I open http://myserver/, it is rewritten to http://myserver/somepage.aspx
If I open http://myserver/somesubdir, it is rewritten to
http://myserver/somesubdir/somepage.aspx
If I open http://myserver/someNonExistantSubDir, it is rewritten to
http://myserver/someNonExistantSubDir/somepage.aspx

This happens although there is no default.aspx page in any directories.

New behaviour (WinXP Sp2 IIS 5.1):
-registered an httpmodule in web.config
-the module implements BeginRequest
-the module rewrites any folder-only URLs (i.e. ending in / or without
an extension) to somepage.aspx
-default page for the virtual directory is set to default.aspx (or not,
behaviour is identical)

If I open http://myserver/, I get directory listing denied. id listing is
allowed, I get the contents. BeginRequest never called.
If I open http://myserver/somesubdir, I get directory listing denied.
BeginRequest never called.
If I open http://myserver/someNonExistantSubDir, I get 404 not found.
BeginRequest never called.

In this case, anything ending in .aspx is forwarded to the httpmodule - but
this is definitely different from my previously experienced behaviour.

So I am still wondering exactly what has happened, why - and if there is any
way to continue to rewrite non-.aspx (etc) urls in asp,net

Thank you!

-Inge

 

[Guest]

There was one (minor detail *cough* ) that has slipped my memory during the
months since I last did this -
I added an extension mapping for * to use the asp.net ISAPI filter. Thus I
was able to get my httpmodule to execute even though the document did not
exist etc..
Now, this is not possible on w2k3 server - but it can be done in a dedicated
box below - Wildcard Application Maps.

But in my current WinXP, I can't map * - neither is there a "Wildcard
Application maps".

It does however seem to work fine by specifying a map for ".*" - this is
accepted, and the httpModule is called.

So I guess there is no real change in behaviour (just a slight change in GUI
on the different OS's).

This also means that I just solved my problem - and that Jeffery is right in
stating that this shouldn't normally work. It works because I tell IIS to
shovel everything thrown at it, straight to asp.net for handling. This seems
to work, without hampering such things as serving of static content - but I
would be interested in hearing others opinions on sideeffects caused by this
kind of mapping

cheerio!

-Inge