2. An endless process

A worker with no processes is just a heartbeat. Now we add something startable.

Declare it

Spring Boot

@SynapsysProcess(name = "ticker", type = ENDLESS)
public class Ticker extends AbstractSynapsysProcess {

    @Override
    public void run(StopSignal stop) {
        while (!stop.requested()) {
            log.info("tick");
            stop.sleep(Duration.ofSeconds(2));
        }
        log.info("stopped cleanly");
    }
}

stop.sleep is not Thread.sleep — it returns early when a stop arrives, so a process with a long interval still stops promptly.

Raw API

Declare it by including it in the batch:

{
  "workerName": "hello-worker",
  "framework": "curl",
  "host": "laptop",
  "heartbeatInterval": 5,
  "processes": [
    { "name": "ticker", "type": "endless", "currentState": "idle", "ackToken": 0 }
  ]
}

The Core creates the process on first sight. Your loop must now read the response and act on it — see applying commands.

Start it

Restart, open the console, find ticker under your worker in state idle, and press Start.

Within one interval the state becomes running and the logs start ticking.

Stop it

Press Stop. Watch the state closely — it becomes stopping first, and only becomes idle once your loop has actually returned.

That intermediate state is real, not cosmetic. It means the Core has asked and is waiting. A process that ignores the stop signal stays in stopping forever, which is exactly the signal you want.

Try breaking it

Press Stop twice quickly. The process stops once.

The second press increments desiredToken again, but by the time your worker sees it the process is already stopping and the applied token has moved past it. This is the token comparison doing its job — see the heartbeat protocol.