pkg/authorization/plugin.go
Tibor Vass 59c8eda724 plugins: experimental support for new plugin management
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>
2016-06-14 14:20:27 -07:00

92 lines
2.1 KiB
Go

package authorization
import (
"sync"
"github.com/docker/docker/pkg/plugins"
)
// Plugin allows third party plugins to authorize requests and responses
// in the context of docker API
type Plugin interface {
// Name returns the registered plugin name
Name() string
// AuthZRequest authorizes the request from the client to the daemon
AuthZRequest(*Request) (*Response, error)
// AuthZResponse authorizes the response from the daemon to the client
AuthZResponse(*Request) (*Response, error)
}
// NewPlugins constructs and initializes the authorization plugins based on plugin names
func NewPlugins(names []string) []Plugin {
plugins := []Plugin{}
pluginsMap := make(map[string]struct{})
for _, name := range names {
if _, ok := pluginsMap[name]; ok {
continue
}
pluginsMap[name] = struct{}{}
plugins = append(plugins, newAuthorizationPlugin(name))
}
return plugins
}
// authorizationPlugin is an internal adapter to docker plugin system
type authorizationPlugin struct {
plugin *plugins.Client
name string
once sync.Once
}
func newAuthorizationPlugin(name string) Plugin {
return &authorizationPlugin{name: name}
}
func (a *authorizationPlugin) Name() string {
return a.name
}
func (a *authorizationPlugin) AuthZRequest(authReq *Request) (*Response, error) {
if err := a.initPlugin(); err != nil {
return nil, err
}
authRes := &Response{}
if err := a.plugin.Call(AuthZApiRequest, authReq, authRes); err != nil {
return nil, err
}
return authRes, nil
}
func (a *authorizationPlugin) AuthZResponse(authReq *Request) (*Response, error) {
if err := a.initPlugin(); err != nil {
return nil, err
}
authRes := &Response{}
if err := a.plugin.Call(AuthZApiResponse, authReq, authRes); err != nil {
return nil, err
}
return authRes, nil
}
// initPlugin initializes the authorization plugin if needed
func (a *authorizationPlugin) initPlugin() error {
// Lazy loading of plugins
var err error
a.once.Do(func() {
if a.plugin == nil {
plugin, e := plugins.Get(a.name, AuthZApiImplements)
if e != nil {
err = e
return
}
a.plugin = plugin.Client()
}
})
return err
}