title: How to use etcd v3 restful api to watch
body: <p>i am trying to watch key with etcdv3 restful api,following <a href="https://github.com/coreos/etcd/blob/master/Documentation/dev-guide/api_grpc_gateway.md" rel="nofollow noreferrer">etcd/Documentation/dev-guide/api_grpc_gateway.md</a>,but it seems not work well with watch.</p>
  
  <pre><code> curl http://localhost:2379/v3beta/watch \
        -X POST -d '{"create_request": {"key":"Zm9v"} }'
  
   curl http://localhost:2379/v3beta/watch \
        -X POST -d '{"create_request": {"key":"Zm9v"} }'
   #{"header":{"cluster_id":"7016043442779247867","member_id":"5993310732371594633","revision":"2","raft_term":"2"}}
  </code></pre>
  
  <p>the watch will not have a response.</p>
  
  <p>this is my docker-compose.yml:</p>
  
  <pre><code>version: "3"
  
  services:
      etcd:
          image: quay.io/coreos/etcd:latest
          command: &gt;
              /usr/local/bin/etcd
              --name node1
              --initial-advertise-peer-urls http://${HOST}:2380
              --listen-peer-urls http://0.0.0.0:2380
              --advertise-client-urls http://${HOST}:2379
              --listen-client-urls http://0.0.0.0:2379
              --initial-cluster node1=http://${HOST}:2380
              --debug
          expose:
              - 2379
              - 2380
          ports:
              - "2379:2379"
              - "3380:2380"
  </code></pre>