In some circumstances we were not properly releasing plugin references,
leading to failures in removing a plugin with no way to recover other
than restarting the daemon.
1. If volume create fails (in the driver)
2. If a driver validation fails (should be rare)
3. If trying to get a plugin that does not match the passed in capability
Ideally the test for 1 and 2 would just be a unit test, however the
plugin interfaces are too complicated as `plugingetter` relies on
github.com/pkg/plugin/Client (a concrete type), which will require
spinning up services from within the unit test... it just wouldn't be a
unit test at this point.
I attempted to refactor this a bit, but since both libnetwork and
swarmkit are reliant on `plugingetter` as well, this would not work.
This really requires a re-write of the lower-level plugin management to
decouple these pieces.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
Go style calls for mixed caps instead of all caps:
https://golang.org/doc/effective_go.html#mixed-caps
Change LOOKUP, ACQUIRE, and RELEASE to Lookup, Acquire, and Release.
This vendors a fork of libnetwork for now, to deal with a cyclic
dependency issue. The change will be upstream to libnetwork once this is
merged.
Signed-off-by: Aaron Lehmann <aaron.lehmann@docker.com>
The current GetAll handles both V2 and legacy plugins. Also due to the
nature of V1 plugins, it also loads them. This causes problems when
loading is not required. Hence adding an independent API that will
return only the plugins that are loaded using v2 mangaed plugins.
Signed-off-by: Madhu Venugopal <madhu@docker.com>
Adds 2 new methods to v2 plugin `Acquire` and `Release` which allow
refcounting directly at the plugin level instead of just the store.
Since a graphdriver is initialized exactly once, and is really managed
by a separate object, it didn't really seem right to call
`getter.Get()` to refcount graphdriver plugins.
On shutdown it was particularly weird where we'd either need to keep a
driver reference in daemon, or keep a reference to the pluggin getter in
the layer store, and even then still store extra details on if the
graphdriver is a plugin or not.
Instead the plugin proxy itself will handle calling the neccessary
refcounting methods directly on the plugin object.
Also adds a new interface in `plugingetter` to account for these new
functions which are not going to be implemented by v1 plugins.
Changes terms `plugingetter.CREATE` and `plugingetter.REMOVE` to
`ACQUIRE` and `RELEASE` respectively, which seems to be better
adjectives for what we're doing.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
Legacy plugins expect host-relative paths (such as for Volume.Mount).
However, a containerized plugin cannot respond with a host-relative
path. Therefore, this commit modifies new volume plugins' paths in Mount
and List to prepend the container's rootfs path.
This introduces a new PropagatedMount field in the Plugin Config.
When it is set for volume plugins, RootfsPropagation is set to rshared
and the path specified by PropagatedMount is bind-mounted with rshared
prior to launching the container. This is so that the daemon code can
access the paths returned by the plugin from the host mount namespace.
Signed-off-by: Tibor Vass <tibor@docker.com>
plugingetter is indepedent of docker/docker packages, so it can be
moved to pkg. This is also necessary for authorization plugins (part of
pkg) to use pluginv2. The original path at plugin/getter will be
eventually removed, when external repos (eg. libnetwork) update their
import paths.
Signed-off-by: Anusha Ragunathan <anusha@docker.com>
