[Qt5-feedback] Add QtService to Qt proper

[BRM]

----- Original Message ----

> From: BRM <bm_witness at yahoo.com>
> ----- Original Message ----
> > From: Thiago Macieira <thiago at kde.org>
> > On Thursday, 19 de  May de 2011 08:48:29 Craig.Scott at csiro.au wrote:
> > >  On  19/05/2011, at 4:42 AM, Thiago Macieira wrote:
> > > > On  Wednesday, 18 de  May de 2011 11:20:25 BRM wrote:
> > > >> It  could also use some TLC, for  example:
> > > > Who's going to  give it that TLC?
> > > 
> > > Well, if  Nokia shows interest  in adding the QtService functionality to 
Qt
> > > and you  ask  nicely......
> > > 
> > > That's one of the things this list is  for,  right? ;)
> > 
> > Nokia has no interest in adding it. The  question is whether you  do, not 
us.
> > 
> 
> I have an interest in  seeing it added as I use it for 90% of my Qt-based 
> applications right now.  Presently I have to map in the existing QtService as a 
>
> 3rd party extension,  which I then instantiate a template from, and derive from 
>
> that to make my  own service class for how my services work. As a result, I 
>have 
>
> to map that  code in twice - once in the static library for my service class, 
>and 
>
> again  in the main application build (I just refer to the code for the library 
>to 
>
> keep down the redundancy) - which is a pain to do. It's also frustrating  that 

> there have been no updates to it since 4.5, and while it works with 4.6  and 
>4.7 
>
> it doesn't list them as supported either.
> 
> So I'd certainly be  interested in being a co-developer with someone on this - 

> I'm not sure my  employer will go for it - especially as it is very peripheral 
>to 
>
> our main  issues at the moment, but they'd certainly benefit; and I do have 
>quite 
>
> a  few applications I can use as a test bed of sorts - though I can't make them 
>
> available for all. I suspect some KDE stuff could potentially use it too -  or 
>at 
>
> least derive from it for someone more KDE centric - the benefit being  that 
> background applications for KDE on Windows would be able to be full  Windows 
> Services as well (e.g. kded4, klauncher - don't know just a couple  quick 
> examples I pulled from Process Explorer). It also wouldn't be hard to  make a 
>few 
>
> examples either.
> > > QtService is presently   only supported via an add-on to Qt. I would be 
>very 
>
> > > helpful to  have it  be part of the official Qt instead of an add-on - e.g. 
>
> >it's 
> > > distributed  with Qt just like  QtGui.
> > > It could also use some TLC, for  example:
> > > - QtService is presently a set of template classes,  making  use of 
> >Signal/slots 
> > > hard. It could probably be  better done using  Abstract classes to define 
>the 
>
> > >  interface.
> > > - It would be useful  to schedule shutdown as  opposed to having the '-t' 
> >option 
> > > simply   terminate it; probably '-t' should be "--force-shutdown" instead.
> > > -  The  "Interactive Service" functionality could probably be removed given 
>
> >that 
> > > (i) adding GUIs to services is not adviced,  and (ii) Windows no longer  
> >supports 
> > > it (as  of Vista). Other platforms may but we probably should  follow best 

> >  > practices and encourage developers to split the service  from the  GUI.
> > I very much agree with this, and given that the  move to  Qt5 is going to 
>have 
>
> >binary compatibility breaks, it would  seem to be an  opportune time to really 
>
> >consider bringing an  improved/restructured QtService  class into Qt proper. I 
>
> >agree with  Ben's view that the current templated  approach is both 
>unnecessary 
>
> >and a hinderance. Dispensing with the GUI support  should make for  a much 
> >cleaner class, and as Ben pointed out, a GUI should  really  be split from the 
>
> >service itself anyway. QtService is one of those  things  that I find myself 
> >asking "Why isn't this part of the main  Qt libraries  already?". It makes 
>sense 
>
> >and fits nicely with the  other set of classes provided  by Qt. I put it at a 

> >similar level  as QDesktopServices, QProcess and  QSharedMemory.
> > One of  the trickier bits of using QtService at the moment  is if you want to 
>
> >support additional command-line options beyond those defined  by  QtService. 
>This 
>
> >is hard enough to do robustly that we basically don't  want to  do it and 
>instead 
>
> >work around it. Maybe the command-line  handling should be done  separately 
>from 
>
> >the QtService class and  have QtService provide member functions  to do the 
> >equivalent  instead? FWIW, we ended up implementing our own generic  (and 
> >extensible) command line argument processing class for some other work,  so  
>we 
>
> >have the other half of this picture. I could understand if  others would be  
>less 
>
> >keen to forego the bundled command-line  capabilities within QtService as it  
>is 
>
> >currently  implemented.
> I would probably suggest it be in parallel to  QCoreApplication/QApplication - 
>a 
>
> simple  QService/QDaemon/QDaemonService.
> 
> I also very much agree that the  command-line support needs great improvement 
>as 
>
> well. Though I'm not sure  that can be done with the present communications 
> mechanism between the  controller and actual daemon - at least as it stands 
>now. 
>
> Not sure if  continuing the 'file' controller interface is best, or whether a 
> shared  memory or network interface would be better - or may even a combination 
>
> thereof (e.g. continue with the file interface for some basic commands, but  
>then 
>
> use another interface via network or shared memory to do more advanced  
>things.).
> 

Yes - I am volunteering to jointly develop this with someone, whether I get paid 
(by my employer) to do so or not.
I will be able to test Linux Embedded, X11, and Windows platforms.

We would need someone to help out with Mac, especially given some of the 
neat/weird things daemons/services do on Mac; as well as other platforms (e.g. 
mobile platforms, etc.)

Thiago,

What do I need to do to help with this? Do I need to setup a project on SF.net 
for the time being and then later get it accepted into Qt?
Or is there a way I can work in a Qt provided sandbox (e.g. project space 
provided by Nokia/Qt)?

Thanks,

Ben