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>
(cherry picked from commit f29bbd16f5)
Signed-off-by: Victor Vieux <vieux@docker.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>
(cherry picked from commit c54b717caf)
Signed-off-by: Victor Vieux <vieux@docker.com>
As part of making graphdrivers support pluginv2, a PluginGetter
interface was necessary for cleaner separation and avoiding import
cycles.
This commit creates a PluginGetter interface and makes pluginStore
implement it. Then the pluginStore object is created in the daemon
(rather than by the plugin manager) and passed to plugin init as
well as to the different subsystems (eg. graphdrivers, volumedrivers).
A side effect of this change was that some code was moved out of
experimental. This is good, since plugin support will be stable soon.
Signed-off-by: Anusha Ragunathan <anusha@docker.com>
Split plugin package into `store` and `v2/plugin`. Now the functionality
is clearly delineated:
- Manager: Manages the global state of the plugin sub-system.
- PluginStore: Manages a collection of plugins (in memory and on-disk)
- Plugin: Manages the single plugin unit.
This also facilitates splitting the global PluginManager lock into:
- PluginManager lock to protect global states.
- PluginStore lock to protect store states.
- Plugin lock to protect individual plugin states.
Importing "github.com/docker/docker/plugin/store" will provide access
to plugins and has lesser dependencies when compared to importing the
original monolithic `plugin package`.
Signed-off-by: Anusha Ragunathan <anusha@docker.com>
Legacy plugin model maintained a map of plugins. This is
not used by the new model. Using this map in the new model
causes incorrect lookup of plugins. This change uses adds
a plugin to the map only if its legacy.
Signed-off-by: Anusha Ragunathan <anusha@docker.com>
This patch introduces a new experimental engine-level plugin management
with a new API and command line. Plugins can be distributed via a Docker
registry, and their lifecycle is managed by the engine.
This makes plugins a first-class construct.
For more background, have a look at issue #20363.
Documentation is in a separate commit. If you want to understand how the
new plugin system works, you can start by reading the documentation.
Note: backwards compatibility with existing plugins is maintained,
albeit they won't benefit from the advantages of the new system.
Signed-off-by: Tibor Vass <tibor@docker.com>
Signed-off-by: Anusha Ragunathan <anusha@docker.com>
This is similar to network scopes where a volume can either be `local`
or `global`. A `global` volume is one that exists across the entire
cluster where as a `local` volume exists on a single engine.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
This generates an ID string for calls to Mount/Unmount, allowing drivers
to differentiate between two callers of `Mount` and `Unmount`.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
This helps ensure that only one thing is trying to intialize a plugin at
once while also keeping the global lock free during initialization.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
Makes `docker volume ls` and `docker volume inspect` ask the volume
drivers rather than only using what is cached locally.
Previously in order to use a volume from an external driver, one would
either have to use `docker volume create` or have a container that is
already using that volume for it to be visible to the other volume
API's.
For keeping uniqueness of volume names in the daemon, names are bound to
a driver on a first come first serve basis. If two drivers have a volume
with the same name, the first one is chosen, and a warning is logged
about the second one.
Adds 2 new methods to the plugin API, `List` and `Get`.
If a plugin does not implement these endpoints, a user will not be able
to find the specified volumes as well requests go through the drivers.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
- Add unit tests to make sure the functionality is correct.
- Add FilterByDriver to allow filtering volumes by driver, for future
`volume ls` filtering and whatnot.
Signed-off-by: David Calavera <david.calavera@gmail.com>
This is not a public interface and users are trying to use it.
We only use it to be able to generate the rpc protocol to talk with a plugin.
Signed-off-by: David Calavera <david.calavera@gmail.com>
This patch makes it such that plugin initialization is synchronized
based on the plugin name and not globally
Signed-off-by: Darren Shepherd <darren@rancher.com>
- comments on exported values
- constant string replaced by constant reference
- unexport implementation details of VolumeDriver 'local'
- add fixed packages to linter list
Signed-off-by: Morgan Bauer <mbauer@us.ibm.com>
Signed by all authors:
Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
Signed-off-by: Arnaud Porterie <arnaud.porterie@docker.com>
Signed-off-by: David Calavera <david.calavera@gmail.com>
Signed-off-by: Jeff Lindsay <progrium@gmail.com>
Signed-off-by: Alexander Morozov <lk4d4@docker.com>
Signed-off-by: Luke Marsden <luke@clusterhq.com>
Signed-off-by: David Calavera <david.calavera@gmail.com>
