Re: [RFC] Health Thermometer Profile API

Hi,

2011/6/22 Elvis Pfutzenreuter [off-list ref]:

On Jun 22, 2011, at 7:20 AM, Santiago Carot wrote:

quoted

Hi,

2011/6/21 Elvis Pfutzenreuter [off-list ref]:

quoted

On Jun 21, 2011, at 12:56 PM, Santiago Carot wrote:

(cut)

quoted

quoted

Another option would be to guarantee that MeasureReceived() is called
right after agent registering, in order to give the client an
initial value to show (having in mind that notification interval might
be very long).

I would prefer to use the Final and Intermediate properties too. The
problem that we should address occurs when an application wich hasn't
got a watcher registered sets Intermediate or Final measurement
property and the last watcher is removed. I think that the best option
may be turn off measurments for power safe due that no watcher will
get the measures.

I'm not sure I follow. Enabling intermediate and/or final notifications
is done per-agent basis; if any of active agents needs intermediate
measurements, device is configured to send them. Disabling it on one
agent should not hurt another.

I mean the case when a process (it is not neccesary it has to be an
agent) is enabling intermediate and/or final notifications through
setProperty method in D-Bus API. Please, note that any process can do
this in current API because no extra control is done for this
operation.

May be I'm misundertanding what you want to said with per-agent basis
but as far as I see the only way to manage enabling/disabling
properties in this way is by adding a new parameter in setProperty
method with the agent path and checkicng if it is already registered
before enabling or disabling intermediate and final notifications. IMO
If we do this we would break the BlueZ APIs where no extra parameters
are required in such methods. I'm not sure if this would be a problem
but I don't feel comfortable with this solution.

On the other hands, if we discard adding the agent parameter in that
method (which I think that it fits better in BlueZ API), we can ignore
the case when there aren't any agents registered for the thermometer
service and a process enables some of this properties. In this case it
wouldn't be necessary to activate these properties since no one will
receive notifications for the measures.

True, I did not remember that those were properties. They would have
to go, otherwise it is too easy for an app to "break" another, by
disabling notifications.

A pair of Enable/DisableIntermediate methods taking an agent as
parameter would be more adequate.

IMHO there would not be a need of such
methods for final measure, because the final measurement (which is
the only one guaranteed to be precise) is the final objective, there
is no point in registering an agent and not wanting a final measurement.

They werent in this RFC. I only see a problem now, for example if an
agent wants to get only a single *final* measure without setting an
interval and after a while the same agents decides that it wants to
get a new single measure without setting an interval for periodic
measurements. I don't see how it could do this with current API (where
get final measure methods are not present).

We could think that an agent is only registered during the time it is
interested in being notified about final measures, after that, it
should unregister itself from the service. In that scenario we can set
notify property for final measures each time an agent is registered
(if not periodic interval is already set).

Any suggestion?

Regards.