[AG-DEV] Getting more than one service stream

[Derek Piper]

Thomas D. Uram wrote:
> Derek:  Sorry it took some time to get back to you.  See comments inline...

No problem, Tom :) My responses also inline.

> On 1/13/06 10:38 AM, Derek Piper wrote:
> 
>>
>>     Hi Thomas,
>>
>>     Thanks for getting back with me. I see what you mean about 
>> connecting to the venue and getting the information that way. I have a 
>> few thoughts on that:
>>
>> - If the participants move venue, we have to manually go and change 
>> the recorder, unless there's a 'follow participant' thing?
> 
> 
> Good point.  There is no follow participant functionality, but I've thought
> that it would be useful to add some observer functionality for applications
> that care about venue client activity.  That would address this 
> problem.  If
> that's a priority for you, I'd suggest you add it to bugzilla as a feature
> request.  Also, the code to do so would be pretty simple, so if you want to
> figure it out and submit code with the request, that'd be great.

Heh, yea, that probably would be great :>

One thing that may be possible to add in the venue client is a simple 
callback that runs a program (or programs in a list) when the venue is 
changed.

If the venue client could then supply arguments to these processes for 
the different streams etc. (in '<stream type>/<host>/<port>/ttl>'

If that were possible, then I wouldn't have to pretend to be a service.

> Given the amount of data generated by a recorder, though, I would think
> people would want to record more selectively, instead of recording
> in every room they visit.

Yes, my idea was to have the program run from the session startup query 
the state of the running AGVCR to see if it's already recording. If it 
is, it carries on recording. If not, it doesn't.

>>
>> - Very good point you make about obtaining the entire list of streams. 
>> I certainly would want to have the mlb and screenstreamer entries for 
>> example, and whatever else comes along the way. It's probably not 
>> possible to do that from a service I'm guessing.

Is it possible to just say you're interested in everything the venue has 
to offer? i.e. 'CAPABILITY_ALL'?

>> - Is it possible to get the encryption key from this venue client 
>> method? it's not displayed in the venue client 'properties' (even 
>> though it is in VIC/RAT etc.)
> 
> 
> The encryption key is included in the StreamDescription, which is what
> you get in both cases (service, or SOAP call to venue client).  It's just
> not displayed in the Venue properties dialog (it is, however, in AG3).

Ah, okay, that's good to know.

> 
>>
>>     My reason for the service idea was this:
>>
>> - AGVCRService can come up automatically when a venue is loaded, get 
>> its services and call the AGVCR executable with the relevant options

>>
>> - Thus the recording 'follows' the participants, accounting for 
>> bridged/non-bridged encrypted/non-encrypted venues as needed.
> 
> 
> Given that, in this case, AGVCR is started by AGVCRService, the state of
> 'whether AGVCR is already running' could to some extent be captured by
> the service, which would then execute or message as appropriate.  Just a
> thought.

Yea, that's a good point. I didn't know if the services kinda got 
'reset' between venue changes or if some sort of persistent state is kept.

I'll look over the venue client stuff again. I'm concerned about making 
AGVCR too dependent on any AG toolkit version or needing any specific 
python file installed into the toolkit to make it work (i.e. to get the 
info I need).

Bears some thinking :)

	Derek

-- 
Derek Piper - dcpiper at indiana.edu - (812) 856 0111
IRI 323, School of Informatics
Indiana University, Bloomington, Indiana