Currently `--publish-rm` only accepts `<TargetPort>` or `<TargetPort>[/Protocol]`
though there are some confusions.
Since `--publish-add` accepts `<PublishedPort>:<TargetPort>[/Protocol]`, some user
may provide `--publish-rm 80:80`. However, there is no error checking so the incorrect
provided argument is ignored silently.
This fix adds the check to make sure `--publish-rm` only accepts `<TargetPort>[/Protocol]`
and returns error if the format is invalid.
The `--publish-rm` itself may needs to be revisited to have a better UI/UX experience,
see discussions on:
https://github.com/docker/swarmkit/issues/1396https://github.com/docker/docker/issues/25200#issuecomment-236213242https://github.com/docker/docker/issues/25338#issuecomment-240787002
This fix is short term measure so that end users are not misled by the silently ignored error
of `--publish-rm`.
This fix is related to (but is not a complete fix):
https://github.com/docker/swarmkit/issues/1396
Signed-off-by: Yong Tang <yong.tang.github@outlook.com>