[maemo-developers] Developping DBus Services

[From: Fred Lefévère-Laoide]

Hi,

I had an idea in the early hours of the morning.

I think it would be very nice for users to be able to use their data in 
different applications and particularly contacts informations ie :
- use addresses or GPS coordinates in MaemoMapper
- use email addresses in a mail client
- use phone numbers in phonelink (ok ok)
- ...

Those contact informations could be stored in GPE or Contacts or 
where-ever each user wants it to be...

The best way to achieve this would be to establish a "weak" link between 
  the applications.
I suppose that DBus would be the best way to achieve this "weak" link.

Then a client application (MaemoMapper, mailClient, phonelink ...) would 
only need to request a DBus Service to know the availability of the 
informations ...

What do you think ?

I'll go and try to find informations on writing DBus services.
 From what I understand DBus would start the application when needed.
If you've got any pointer ...

I suppose 2 services can not respond to the same DBus id ?
Should I then manage a generic service that would redirect calls to 
different specific services (GPE, Contacts ...)

I suppose the best programming language for this would be c ?

The service that I plan would provide 2 methods

1: GetAvailableContactInfos
****************************
Param in :
==========
- Requested Infos (List of constants)
	nothing or a list of predefined types ex : GPSCoordinate, FullAddress, 
City, MobilePhoneNumber, PhoneNumbers ...
Param out :
===========
- Available Infos (List of Constants)
	if nothing requested all the available types of informations, If 
requested the ones available
Return :
========
Found, NotFound, ErrorCode

2: GetContactInfos
*******************
Param in :
==========
- Requested Infos (List of constants)
	nothing or a list of predefined types ex : GPSCoordinate, FullAddress, 
City, MobilePhoneNumber, PhoneNumbers ...
- Search (String)
	A search string
- ShowGui (Boolean)
	an indicator specifying if a GUI must be shown in case of ambiguity 
(several responses)
- MultipleResponse (Boolean)
	an indicator specifying if the service can reply with a list
Param out :
===========
- Response (List of List of String)
	the results
Return :
========
Found, NotFound, ErrorCode


Thanks for your kind attention and possible help and sorry if I bothered 
you ;)

Fred