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How can catch put and delete events with Watch?

See original GitHub issue

I made a watch with jetcd 0.5.0, and process event with LoggingWatchListener. but It only call when any event complete, how can do like etcdctl:

Here is my code:

public void keepWatch(String key){
        if (watchMap.containsKey(key)==false) {
            Watch watch = etcdClient.getWatchClient();
            ByteSequence keyBS = ByteSequence.from(key, StandardCharsets.UTF_8);
            Watch.Watcher watcher=watch.watch(
                    keyBS,
                    WatchOption.DEFAULT,
                    new LoggingWatchListener());
            log.debug("watch on key[{}]",key);
        }
        else{
            log.debug("we had watched on key[{}]",key);
        }
    }

class LoggingWatchListener implements Watch.Listener {
        @Override
        public void onNext(WatchResponse response) {
            log.info("watch[listener] - nextEvent");
            for(WatchEvent event:response.getEvents()){
                log.debug("watch[listener] - nextEvent - type:{}, KV:{}, PreKV:{}",
                        event.getEventType(),event.getKeyValue(),event.getPrevKV()
                );
            }

        }

        @Override
        public void onError(Throwable throwable) {
            log.error("watch[listener] - errorEvent - something wrong: {}",throwable.getMessage(),throwable);
        }

        @Override
        public void onCompleted() {
            log.debug("watch[listener] - completedEvent");
        }
    }

Issue Analytics

State:
Created 3 years ago
Comments:14

Top GitHub Comments

3reactions

cleverpigcommented, Nov 24, 2020

I translated groove to java class, this doesn’t work for me.

public void testKeepWatch2() throws InterruptedException {
        Client client = Client.builder().endpoints("http://localhost:2379").build();
        Watch watch = client.getWatchClient();
        KV kv = client.getKVClient();
        ByteSequence key = ByteSequence.from(UUID.randomUUID().toString(), StandardCharsets.UTF_8);

        watch.watch(
                key,
                WatchOption.newBuilder().withProgressNotify(true).withPrevKV(true).build(),
                new Watch.Listener() {
                    @Override
                    public void onNext(WatchResponse response) {
                        log.info("onNext");
                    }

                    @Override
                    public void onError(Throwable throwable) {
                        log.error("onError - something wrong: {}", throwable.getMessage(), throwable);
                    }

                    @Override
                    public void onCompleted() {
                        log.debug("onCompleted");
                    }
                }
        );

        for(int i=0;i<99;i++){
            kv.put(key, ByteSequence.from(UUID.randomUUID().toString(), StandardCharsets.UTF_8));
            log.debug("put [{}]times",i+1);
            Thread.sleep(1000);
        }
    }

logging output without any listener’s event:

2020-11-24 11:22:50,669 DEBUG [com.bjinfotech.practice.etcd.EtcdUtilTest]:116 - <put [1]times>
2020-11-24 11:22:51,674 DEBUG [com.bjinfotech.practice.etcd.EtcdUtilTest]:116 - <put [2]times>
2020-11-24 11:22:52,674 DEBUG [com.bjinfotech.practice.etcd.EtcdUtilTest]:116 - <put [3]times>
2020-11-24 11:22:53,674 DEBUG [com.bjinfotech.practice.etcd.EtcdUtilTest]:116 - <put [4]times>
2020-11-24 11:22:54,674 DEBUG [com.bjinfotech.practice.etcd.EtcdUtilTest]:116 - <put [5]times>
2020-11-24 11:22:55,674 DEBUG [com.bjinfotech.practice.etcd.EtcdUtilTest]:116 - <put [6]times>
2020-11-24 11:22:56,674 DEBUG [com.bjinfotech.practice.etcd.EtcdUtilTest]:116 - <put [7]times>
2020-11-24 11:22:57,674 DEBUG [com.bjinfotech.practice.etcd.EtcdUtilTest]:116 - <put [8]times>
2020-11-24 11:22:58,674 DEBUG [com.bjinfotech.practice.etcd.EtcdUtilTest]:116 - <put [9]times>
....

etcd server output:

2020-11-24 11:22:51.602118 D | etcdserver/api/v3rpc: start time = 2020-11-24 11:22:51.6021187 +0800 CST m=+1093.828563401, time spent = 0s, remote = 127.0.0.1:54043, response type = /etcdserverpb.KV/Put, request count = 1, request size = 76, response count = 0, response size = 28, request content = key:"c291e080-825b-4990-a2f1-f1666d1d7cd8" value_size:36
2020-11-24 11:22:51.722125 D | etcdserver/api/v3rpc: start time = 2020-11-24 11:22:51.677123 +0800 CST m=+1093.903567701, time spent = 45.0026ms, remote = 127.0.0.1:54043, response type = /etcdserverpb.KV/Put, request count = 1, request size = 76, response count = 0, response size = 28, request content = key:"c291e080-825b-4990-a2f1-f1666d1d7cd8" value_size:36
2020-11-24 11:22:52.678180 D | etcdserver/api/v3rpc: start time = 2020-11-24 11:22:52.6781803 +0800 CST m=+1094.904625001, time spent = 0s, remote = 127.0.0.1:54043, response type = /etcdserverpb.KV/Put, request count = 1, request size = 76, response count = 0, response size = 28, request content = key:"c291e080-825b-4990-a2f1-f1666d1d7cd8" value_size:36
2020-11-24 11:22:53.677237 D | etcdserver/api/v3rpc: start time = 2020-11-24 11:22:53.6762373 +0800 CST m=+1095.902682001, time spent = 1.0001ms, remote = 127.0.0.1:54043, response type = /etcdserverpb.KV/Put, request count = 1, request size = 76, response count = 0, response size = 28, request content = key:"c291e080-825b-4990-a2f1-f1666d1d7cd8" value_size:36
2020-11-24 11:22:54.678294 D | etcdserver/api/v3rpc: start time = 2020-11-24 11:22:54.6782947 +0800 CST m=+1096.904739401, time spent = 0s, remote = 127.0.0.1:54043, response type = /etcdserverpb.KV/Put, request count = 1, request size = 76, response count = 0, response size = 28, request content = key:"c291e080-825b-4990-a2f1-f1666d1d7cd8" value_size:36
2020-11-24 11:22:55.677351 D | etcdserver/api/v3rpc: start time = 2020-11-24 11:22:55.6773518 +0800 CST m=+1097.903796501, time spent = 0s, remote = 127.0.0.1:54043, response type = /etcdserverpb.KV/Put, request count = 1, request size = 76, response count = 0, response size = 28, request content = key:"c291e080-825b-4990-a2f1-f1666d1d7cd8" value_size:36
2020-11-24 11:22:56.678409 D | etcdserver/api/v3rpc: start time = 2020-11-24 11:22:56.6784091 +0800 CST m=+1098.904853801, time spent = 0s, remote = 127.0.0.1:54043, response type = /etcdserverpb.KV/Put, request count = 1, request size = 76, response count = 0, response size = 28, request content = key:"c291e080-825b-4990-a2f1-f1666d1d7cd8" value_size:36

Btw, which etcdServer version are your? I tried 3.3.25 and 3.4.13.

0reactions

SadykovRcommented, Jun 10, 2022

I have the same issue. I tried to put and get values and it works well, but Watch doesnt works - Watch.Listener doesn’t fires when I put a value. I use 0.5.0 version. P.S. Also tried to add Watch and test it using etcdctl tool on the same server - works fine.