[STORM-2568] 'api/vi/topology/:id/lag' returns empty json {}

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.1.0
• Fix Version/s: 1.1.1, 1.2.0
• Component/s: storm-core
• Assignee: Haewan Jeong
• Reporter: Haewan Jeong
• Created: 23/Jun/17 05:14
• Updated: 03/Jul/17 15:36
• Resolved: 25/Jun/17 14:32

Description

Hello

I've tried to use storm-kafka-monitor, and it works fine on command line If I changed 'toollib/storm-kafka-monitor-*.jar' to 'toollib/storm-kafka-monitor-1.1.0.jar'.

{"my-kafka-topic-name":{"0":{"consumerCommittedOffset": 74804998, "logHeadOffset": 74805483, "lag": 485},"1":{"consumerCommittedOffset": 74804998, "logHeadOffset": 74805485, "lag": 487},"2":{"consumerCommittedOffset": 74804995, "logHeadOffset": 74805485, "lag": 490},"3":{"consumerCommittedOffset": 74805001, "logHeadOffset": 74805488, "lag": 487},"4":{"consumerCommittedOffset": 74805011, "logHeadOffset": 74805484, "lag": 473},"5":{"consumerCommittedOffset": 74805009, "logHeadOffset": 74805485, "lag": 476},"6":{"consumerCommittedOffset": 74805008, "logHeadOffset": 74805483, "lag": 475},"7":{"consumerCommittedOffset": 74805010, "logHeadOffset": 74805484, "lag": 474},"8":{"consumerCommittedOffset": 73641446, "logHeadOffset": 74805488, "lag": 1164042},"9":{"consumerCommittedOffset": 73641448, "logHeadOffset": 74805489, "lag": 1164041},"10":{"consumerCommittedOffset": 73641443, "logHeadOffset": 74805483, "lag": 1164040},"11":{"consumerCommittedOffset": 73641445, "logHeadOffset": 74805487, "lag": 1164042},"12":{"consumerCommittedOffset": 74805003, "logHeadOffset": 74805486, "lag": 483},"13":{"consumerCommittedOffset": 74804999, "logHeadOffset": 74805482, "lag": 483},"14":{"consumerCommittedOffset": 74805002, "logHeadOffset": 74805483, "lag": 481},"15":{"consumerCommittedOffset": 74805002, "logHeadOffset": 74805484, "lag": 482},"16":{"consumerCommittedOffset": 74804994, "logHeadOffset": 74805482, "lag": 488},"17":{"consumerCommittedOffset": 74805002, "logHeadOffset": 74805489, "lag": 487},"18":{"consumerCommittedOffset": 74805003, "logHeadOffset": 74805488, "lag": 485},"19":{"consumerCommittedOffset": 74805003, "logHeadOffset": 74805489, "lag": 486}}}

but it gives empty result when I call below api.

/api/v1/topology/:id/lag
...

{
"MySpoutName": {
"spoutLagResult": {},
"spoutId": "MySpoutName",
"spoutType": "KAFKA"
}
}

I think that needs to fix "groupid" to "group.id" in TopologySpoutLag.java I debug it, but groupid is right.

the reason was topics has square brackets in command.

2017-06-23 19:55:56.725 o.a.s.u.TopologySpoutLag qtp426435961-51 [INFO] json configuration: {config.security.protocol=null, config.bootstrap.servers=kafka.xxx.com:9092, config.topics=[my-kafka-topic], config.groupid=my-storm-kafka-spout-groupid, topology.tasks=5}

2017-06-23 19:55:56.725 o.a.s.u.TopologySpoutLag qtp426435961-51 [INFO] /my/program/storm/bin/storm-kafka-monitor
2017-06-23 19:55:56.725 o.a.s.u.TopologySpoutLag qtp426435961-51 [INFO] -t
2017-06-23 19:55:56.725 o.a.s.u.TopologySpoutLag qtp426435961-51 [INFO] [my-kafka-topic]
2017-06-23 19:55:56.725 o.a.s.u.TopologySpoutLag qtp426435961-51 [INFO] -g
2017-06-23 19:55:56.725 o.a.s.u.TopologySpoutLag qtp426435961-51 [INFO] my-storm-kafka-spout-groupid
2017-06-23 19:55:56.725 o.a.s.u.TopologySpoutLag qtp426435961-51 [INFO] -b
2017-06-23 19:55:56.725 o.a.s.u.TopologySpoutLag qtp426435961-51 [INFO] kafka.xxx.com:9092

the square brackets automatically added because of this

package org.apache.storm.kafka.spout;
public class NamedSubscription extends Subscription {
...
    @Override
    public String getTopicsString() {
        return String.valueOf(topics);
    }

topics is Collections. so String.valueOf returns value with square brackets.

I fixed the code that remove square brackets in TopologySpoutLag.java for my case.
but I think that fixing 'getTopicsString of NamedSubscription.java in org.apache.storm.kafka.spout' is might be better.

Issue Links

• links to: GitHub Pull Request #2177