Can a Spout or Bolt access the ID by which it is known in the Topology?

Question

Is there an API for a Storm Spout or Bolt to access its ID? The ID I am referring to is the String that was passed to the setSpout or setBolt method in class backtype.storm.topology.TopologyBuilder.

It would be useful to access this string for the logging purposes.

Answer 1

You can use getThisComponentId() on the passed topology context in the prepare method for bolts:

@Override
public void prepare(Map config, TopologyContext context, OutputCollector collector) {
    this.collector = collector;

    String componentId = context.getThisComponentId();
}

and in the open method for spouts.

There's also a more general method getComponentId(int taskId) that returns the component id for any given task.