Azure Java functions TimerTrigger to fire on startup

Question

Azure functions with C# provides a way to run the TimerTrigger at starts up time with RunOnStartup parameter as follows.

[FunctionName("TimeTrigger_Startup")]
public async Task Migrations([TimerTrigger("0 */4 * * * *", RunOnStartup = true)] TimerInfo myTimer, ILogger logger) {
     // Startup script
}

But, there is no option for Java TimerTrigger functions.

@FunctionName("Warmup")
public void run(@TimerTrigger(name = "warmupTrigger", schedule = "0 */4 * * * *") String timerInfo, ExecutionContext context) {
   // Startup script
}

There is no equivalent variable for RunOnStartup in annotation @TimerTrigger to start at start time. Is there any work around to execute the method in Azure Java function on startup?

Answer 1

Currently this not possible using annotations. Current work-around is to add these properties in the generated function.json file as described here. There is an open PR which will address this issue.