风暴拓扑是否可以通过喷口或螺栓停用并重新激活？

Question

When certain conditions are met, like encountering a special type of tuple, I want to deactivate the topology . Is this can be done in spout/bolt ? And if yes, is there any way to reactivate the topology from spout/bolt too ?

Answer 1

I have added all three actions in bolow code to activate/deactivate/kill. This can be called from independent java code (outside spout/bolt).

Deactivate from spout or bolt is straight forward but reactivating would be tricky as your spout/bolt is not actively running java program once deactivated.

import backtype.storm.generated.KillOptions;
import backtype.storm.generated.Nimbus.Client;
import backtype.storm.utils.NimbusClient;
import backtype.storm.utils.Utils;

Client client = NimbusClient.getConfiguredClient(Utils.readStormConfig()).getClient();

client.activate(topologyName);
client.deactivate(topologyName);

KillOptions killOpts = new KillOptions();
killOpts.set_wait_secs(30);
client.killTopologyWithOpts(topologyName, killOpts);