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>
The `Status` field is a `map[string]interface{}` which allows the driver to pass
back low-level details about the underlying volume.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
Implements a `CachedPath` function on the volume plugin adapter that we
call from the volume list function instead of `Path.
If a driver does not implement `CachedPath` it will just call `Path`.
Also makes sure we store the path on Mount and remove the path on
Unmount.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
In cases where the a plugin responds with both a null or empty volume
and a null or empty Err, the daemon would panic.
This is because we assumed the idiom if `err` is nil, then `v` must not
be but in reality the plugin may return whatever it wants and we want to
make sure it doesn't harm the daemon.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
Use a back-compat struct to handle listing volumes for volumes we know
about (because, presumably, they are being used by a container) for
volume drivers which don't yet support `List`.
Adds a fall-back for the volume driver `Get` call, which will use
`Create` when the driver returns a `404` for `Get`. The old behavior was
to always use `Create` to get a volume reference.
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>
- Use the ones provided by docker/go-connections, they are a drop in replacement.
- Remove pkg/sockets from docker.
- Keep pkg/tlsconfig because libnetwork still needs it and there is a
circular dependency issue.
Signed-off-by: David Calavera <david.calavera@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>
