I have a ZWave light bulb and a ZWave 4-button wall switch, both connected to Domoticz installed on a Raspberry Pi.

I'd like the following scenarios :

• Button 1 : lamp on for 30 minutes
• Button 2 : lamp off
• Button 3 : lamp always on
• Button 4 : summon Cthulhu

Each buttons overrides the previous action (Button 3 -> Button 1 = on for 30 minutes)

Wiring and programming the buttons is easy, but now, how about the timer ? I'd like to avoid creating a homemade service because I'm afraid of messing with init.d.

I have 3 possibilities :

Domoticz dummy switch

Domoticz allows to create a dummy switch which can change states after some time given in an interface :

Pros

• off-the-shelf timer!
• I can interact quite quickly between my wall switch and the lamp

Cons

• although Domoticz handles MQTT, there will be a lot of LUA script and "blocky" to interconnect devices
• time might not be easily configurable...

at and atq

at is a linux command to plan an action in time, as simple as

at [when] < [what]

Pros

• multi-timer service
• easy to use and call

Cons

• at only gives an unique ID, unless parsing the planned command I can't give a name to the job (unless with a magic linux command...)
• therefore I need to code/implement a job matcher using a database

Crontab

Crontab is a linux service to plan repetitive tasks. In my case it will be a simple

# check every minute
* * * * * /path/checktimer.sh

Pros

• Reliable time trigger

Cons

• Cannot manage seconds...
• Still forced to maintain somewhere a job matcher

To my question :

• Did you have to manage timers like this kind?
• Did I miss other more reliable/configurable solutions?
• Do you have a preference with on the solutions above?