Re: [Py2exe-users] TypeLib info with a COM server

[Thomas H. <th...@ct...>]

Mark Hammond schrieb:
>> comtypes (http://starship.python.net/crew/theller/comtypes) supports
>> this. You have to create a type library, probably with MS tools),
> 
> Excellent!  The only problem I saw was the actual creation of the typelib.

Did you understand what I was trying to say?  I write an IDL file and compile
it with the Microsoft MIDL compiler to get a TLB file.  (Several years ago I
wrote a script that would create a TLB file by using the ICreateTypeLib interface
directly - you may remember it - but this was never used in production).
Nowadays I always use the MIDL compiler, anything else is not worth the effort imo.

> Once you get the typelib itself built, you should be in the exact same
> position with pywin32 as with ctypes - hopefully Thomas can elaborate on
> what steps you need to take (or on what steps pywin32 needs to take to get
> "up-to-par" here...)

The short description for comtypes, once you have the typelib, is this:

- call 'comtypes.client.GetModule(<path-to-typelib.tlb>) to generate the comtypes
  wrapper for the interface(s); this will also print out the name of the generated
  module(s)

- The generated modules contain nearly all the boilerplate code; you now write a script
  that contains the COM server itself by subclassing the generated CoClass in the wrapper.
  Several attributes must be defined in the subclass: the progid and clsid for the coclass
  (these are not in the generated code), plus possibly one or two optional attributes.

- You write a 'if __name__ == "__main__":' section that calls
  comtypes.server.UseCommandline() with your coclass or coclasses (very much as in pywin32)

When you now register the script with 'python myscript.py /regserver' you can already
create instances of the com object, and the com object already implements several interfaces:

 - the interface(s) you have defined in the IDL file
 - IProvideClassInfo
 - ISupportErrorInfo
 - IConnectionPointContainer if the object has outgoing interfaces.

However, methods on the interfaces defined in the IDL file return E_NOTIMPL because
there is no implementation for them - but the generated wrapper code contains commented
out template code that one could copy and paste as a starting point.

A simple py2exe setup script to create a com server dll looks like this:

import py2exe
from distutils.core import setup

TestComServer = dict(
    modules = ["TestComServer"],
    other_resources = [("TYPELIB", 1, file(r"TestComServer.tlb", "rb").read())],
    dest_base = r"testComServer"
    )

setup(name="TestComServer",
      ctypes_com_server = [TestComServer]
      )

What is needed for pywin32?  I guess pywin32 should load the typelib resource
from the tlb file (when running as script) or from the exe/dll (when running frozen)
and expose type information via IProvideClassInfo and IDispatch::GetTypeInfo.
Of course the setup script looks different for a pywin32 com server.

-- 
Thanks,
Thomas