[python-win32] Running a Windows Python service without pythonservice.exe?

[Bill Janssen]

Mark Hammond <skippy.hammond at gmail.com> wrote:

> That's correct.  Using python.exe as the host will involve having a
> .py script which imports the servicemanager module then call
> PrepareToHostSingle and instantiate the service class - or something
> like that :)

How definitive :-).  I'm already generating a python script for each
service, so this could easily be incorporated, if I knew exactly what it
was I have to do.

1.  Set up the sys.path and os.environ["Path"] properly.

2.  import servicemanager

3.  define my class

4.  call servicemanager.PrepareToHostSingle(my class name)

Seem right?

> Another alternative is to ship a slightly modified pythonxx.dll - it
> has a feature where a certain string resource contains the basename of
> the registry key used at runtime to load the pythonpath - eg, you will
> find the resource has "2.6" for Python 2.6 builds.  Using a resource
> editor (or even a script using pywin32) to change this to some custom
> value will mean the pythonpath can be loaded from a private key in the
> registry, meaning you still get isolation from other installed Python
> versions.

I could do that, I guess.  I'd like to be able to script all the
preparations, so if it's a GUI step that would be a Bad Thing.  But a
script using pywin32 would be great.  So, I need to know a couple of
things:

1.  What's the name of this "certain string resource"?

2.  How would one write such a pywin32 script :-)?

I wrote this script to answer question #1:

-----------------------------------------------------------------
import sys, os

import win32api, win32con

handle = win32api.LoadLibrary(sys.argv[1])
for rname in win32api.EnumResourceNames(handle, win32con.RT_STRING):
    rvalue = win32api.LoadResource(handle, win32con.RT_STRING, rname)
    print rname, rvalue
-----------------------------------------------------------------

$ python resource.py python26.dll
63 ^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^C^@2^@.^@6^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@
$

So, the "name" is 63, and it's a 38-byte value with a lot of nul
characters in it.  I'm unsure of just how to hack it with UpdateResource
-- do I just center the replacement text and pad with nul characters?
And what's the registry key this works against, anyway?  I'd have to
update that as part of my installer, too.

Bill