IID and CLSCTX_INPROC_SERVER

[Mark Hammond]

Steve Holden wrote:

> At present I'm using a COM object declared as an in-proc server. This
> appears to have the disadvantage that the IIS (4) process caches the
> object's class definition, so when I change the code there appears to be
> nothing I can do short of rebooting NT to force IIS to recognize the new
> definition.


This is not really IIS's fault, but the way Python handles modules.  A 
Python COM object is loaded from a standard Python module.  So, what 
win32com does is, basically:

import yourmodule
klass = yourmodule.YourClass()

The problem is that this is all done in the same runtime, so the import 
statement will be cached for 2nd and subsequent imports.  Even if IIS 
attempts to unload the Python DLL, Python COM refuses and does not 
unload (mainly due to perf issues).

> Can someone tell me a) whether it's possible to re-initialise with a new
> object definition without rebooting, and/or b) whether this situation will
> be alleviated if I move to using CLSCTX_LOCAL_SERVER?
> 
> I'm not really quite clear enough on the details of COM object registration,
> creating and destruction to see my way through the woods here.


It should be possible to have your ASP code explicitly reload() the 
module.  Eg, you could simply execute some ASP code that does:

import yourmodule
reload(yourmodule)
# create the COM object used

Alternatively, consider using the "Python.Interpreter" COM object to 
explicitly import and reload the module.

Mark.