Fairly straight forward. It became necessary to wrap `Plugin.Err` with a type
which implements `encoding.MarshalText` in order to have that field rendered
properly in the `docker info -f '{{json}}'` output.
Since I changed the type somewhat I also added a unit test for `formatInfo`.
Signed-off-by: Ian Campbell <ijc@docker.com>
Previously a plugin which used these hooks would overwrite the top-level plugin
command's use of this hook, resulting in the dockerCli object not being fully
initialised.
Provide a function which plugins can use to chain to the required behaviour.
This required some fairly ugly arrangements to preserve state (which was
previously in-scope in `newPluginCOmmand`) to be used by the new function.
Signed-off-by: Ian Campbell <ijc@docker.com>
To do this we add a stub `cobra.Command` for each installed plugin (only when
invoking `help`, not for normal running).
This requires a function to list all available plugins so that is added here.
Signed-off-by: Ian Campbell <ijc@docker.com>
Also includes the scaffolding for finding a validating plugin candidates.
Argument validation is moved to RunE to support this, so `noArgs` is removed.
Signed-off-by: Ian Campbell <ijc@docker.com>
That is, the helper to be used from the plugin's `main`.
Also add a `helloworld` plugin example and build integration.
Signed-off-by: Ian Campbell <ijc@docker.com>
Ian Campbell