Add force option to service update

Currently, there's no way to restart the tasks of a service without
making an actual change to the service. This leads to us giving awkward
workarounds as in
https://github.com/docker/docker.github.io/pull/178/files, where we tell
people to scale a service up and down to restore balance, or make
unnecessary changes to trigger a restart.

This change adds a --force option to "docker service update", which
forces the service to be updated even if no changes require that.

Since rolling update parameters are respected, the user can use
"docker service --force" to do a rolling restart. For example, the
following is supported:

   docker service update --force --update-parallelism 2 \
   --update-delay 5s myservice

Since the default value of --update-parallelism is 1, the default
behavior is to restart the service one task at a time.

Signed-off-by: Aaron Lehmann <aaron.lehmann@docker.com>
Upstream-commit: c9fdf9abf8d6443598808809b900d96e04adfcb1
Component: engine
This commit is contained in:
Aaron Lehmann
2016-10-20 12:04:01 -07:00
parent accc5bf3d7
commit 39b84d5fbe
8 changed files with 50 additions and 6 deletions

View File

@ -61,6 +61,10 @@ type TaskSpec struct {
// spec. If not present, the one on cluster default on swarm.Spec will be
// used, finally falling back to the engine default if not specified.
LogDriver *Driver `json:",omitempty"`
// ForceUpdate is a counter that triggers an update even if no relevant
// parameters have been changed.
ForceUpdate uint64
}
// Resources represents resources (CPU/Memory).