Step 5: Firing Instant A-events
This step corresponds to test_agg_lib_5.
Instant A-events are sent to the AggreGate server "on the spot". They are "lightweight" — there is no dealing with storing them on the flash disk, etc. They are fast(er) — just send! They are more reliable — no flash disk complexity involved. They are also easier to be lost. Should your device lose power at a wrong moment, the instant A-event will be forgotten. Another limitation: instant A-events can only be fired successfully when there is an active connection to the AggreGate server. Bottom line: use instant A-events for events that are not-so-important and/or numerous.
In this step we add an instant A-event for reporting the booting (powering up) of the device.
- Aggregate.xtxt now contains the DB instant A-event. This event has only one field — the date/time of the event. It is possible to have additional fields, of course.
- There is a new generate_boot_event() sub is in device.tbs. It calls agg_fire_instant_event() to send the instant A-event to the AggreGate server. We call generate_boot_event() from callback_agg_synchronized(), not on_sys_init(). As was explained above, you need to have an established connection to the AggreGate server in order to be able to fire instant A-events, and the connection is ready when callback_agg_synchronized() is called.
- Notice how this procedure uses agg_record_encode().
- Notice also the use of the TIME library [not yet documented] for producing the date/time field of correct format.
Notice how the add_fire_instant_event() call has the event_level argument. The level defined by this argument will override the default level set in the configurator, unless you set the event_level= E N_AGG_EVENT_LEVEL_USE_DEFAULT, in which case the default event level will be used.
To be able to see instances of your new event, right-click on the device in the tree and choose Monitor Related Events.