lint errors on missing comments for new exported types.

Definitely a +1 from me since I created the issue :)

Yup, +1 from me for changing this. Don't forget to update the docs and man-pages if this moves further.

Should this require backwards compat or should this part of 1.8.2 and thus modify the current API?

My thought is make it part of 1.8.x.

I'm +1 to making it part of 1.8.x, regarding it a "fix" and to reduce the exposure (yes, it's awkward doing an API change in a dot-release, but we should try to avoid people starting to rely on this)

@cpuguy83, @thaJeztah I'm neutral, but this change is completely backwards compatible. Containers started with VolumeDriver in the config still work as expected if stopped and started with this new code.

@calavera Oh yes, makes sense. We have to support already created containers here.

I still see VolumeDriver showing up in the inspect output and not in HostConfig.
It does work, though, as VolumeDriver which was committed to the image is not used by a container created from that image.

@cpuguy83 version numbers are hard! I'm going to add some tests for the inspect output.

I've added a couple of integration tests to prevent regressions. It turned out that I left the field in the config inspect for the next version of docker 😔

LGTM

I've rebased this. Please, take a look.

If I understand correctly, this design still only allows one VolumeDriver per container. What happens if you want to mount one volume using Flocker and one using Convoy?

@bboreham Need to use docker volume create, then bind that volume in using the name.

@calavera external volume tests are failing.

@bboreham using the new volume API volume create command, this should work;

docker run -d \
   -v $(docker volume create --driver=foo):/volume-a/ \
   -v $(docker volume create --driver=bar):/volume-b/ \
   my-image

Ah, right, thanks. Wasn't clear from https://docs.docker.com/extend/plugins_volume/

@bboreham it's not released yet; the volume create command will be in the next release (docker 1.9), but you can experiment with it, by downloading a binary from https://master.dockerproject.org (there are still some bugs, so tread carefully)

@calavera volume test are failing after rerunning the tests.

@crosbymichael I don't know what happened with those tests, but it looks like it's passing now.

LGTM