etcdctl: Proper exit status of endpoint subcommand

[koorgoo]

etcdctl may be used for simple monitoring to check etcd cluster's health.
However, as of now etcdctl endpoint health returns 0 for a dead endpoint.

$ etcdctl endpoint health
127.0.0.1:2379 is unhealthy: failed to connect: dial tcp 127.0.0.1:2379: getsockopt: connection refused
$ echo $?
0

Expected exit statuses of etcdctl endpoint health command:

• for single endpoint:
  • 0 - endpoint is healthy
  • non-0 - endpoint is unhealthy
• for multiple endpoints:
  • 0 - all endpoints are healthy
  • non-0 - one or more endpoints are unhealthy

$ etcdctl version
etcdctl version: 3.2.4
API version: 3.2

[xiang90]

@koorgoo This is a bug. Would you like to help us fix it?

[koorgoo]

@xiang90 Yeah! With pleasure!