plugin.go

/*
Copyright 2016 The Kubernetes Authors All rights reserved.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

package restclient

import (
	"fmt"
	"net/http"
	"sync"

	"github.com/golang/glog"

	clientcmdapi "k8s.io/kubernetes/pkg/client/unversioned/clientcmd/api"
)

type AuthProvider interface {
	// WrapTransport allows the plugin to create a modified RoundTripper that
	// attaches authorization headers (or other info) to requests.
	WrapTransport(http.RoundTripper) http.RoundTripper
}

type Factory func() (AuthProvider, error)

// All registered auth provider plugins.
var pluginsLock sync.Mutex
var plugins = make(map[string]Factory)

func RegisterAuthProviderPlugin(name string, plugin Factory) error {
	pluginsLock.Lock()
	defer pluginsLock.Unlock()
	if _, found := plugins[name]; found {
		return fmt.Errorf("Auth Provider Plugin %q was registered twice", name)
	}
	glog.V(4).Infof("Registered Auth Provider Plugin %q", name)
	plugins[name] = plugin
	return nil
}

func GetAuthProvider(apc *clientcmdapi.AuthProviderConfig) (AuthProvider, error) {
	pluginsLock.Lock()
	defer pluginsLock.Unlock()
	p, ok := plugins[apc.Name]
	if !ok {
		return nil, fmt.Errorf("No Auth Provider found for name %q", apc.Name)
	}
	return p()
}