Make Swagger API support optional, so that consumers can define their own

OpenShift would like to also enable swagger, but we need to register our
services as swagger services prior to the SwaggerAPI being started. I've
added a bool (default false) to master.Config to enable swagger, and split
the method in master out so that a downstream consumer can call it.

cmd/kube-apiserver/apiserver.go

@@ -171,6 +171,7 @@ func main() {
 		PortalNet:             &n,
 		EnableLogsSupport:     *enableLogsSupport,
 		EnableUISupport:       true,
+		EnableSwaggerSupport:  true,
 		APIPrefix:             *apiPrefix,
 		CorsAllowedOriginList: corsAllowedOriginList,
 		ReadOnlyPort:          *readOnlyPort,

pkg/master/master.go

@@ -69,11 +69,15 @@ type Config struct {
 	PortalNet             *net.IPNet
 	EnableLogsSupport     bool
 	EnableUISupport       bool
+	EnableSwaggerSupport  bool
 	APIPrefix             string
 	CorsAllowedOriginList util.StringList
 	Authenticator         authenticator.Request
 	Authorizer            authorizer.Authorizer
 
+	// If specified, all web services will be registered into this container
+	RestfulContainer *restful.Container
+
 	// Number of masters running; all masters must be started with the
 	// same value for this field. (Numbers > 1 currently untested.)
 	MasterCount int
@@ -92,21 +96,23 @@ type Config struct {
 // Master contains state for a Kubernetes cluster master/api server.
 type Master struct {
 	// "Inputs", Copied from Config
-	podRegistry           pod.Registry
-	controllerRegistry    controller.Registry
-	serviceRegistry       service.Registry
-	endpointRegistry      endpoint.Registry
-	minionRegistry        minion.Registry
-	bindingRegistry       binding.Registry
-	eventRegistry         generic.Registry
-	storage               map[string]apiserver.RESTStorage
-	client                *client.Client
-	portalNet             *net.IPNet
+	podRegistry        pod.Registry
+	controllerRegistry controller.Registry
+	serviceRegistry    service.Registry
+	endpointRegistry   endpoint.Registry
+	minionRegistry     minion.Registry
+	bindingRegistry    binding.Registry
+	eventRegistry      generic.Registry
+	storage            map[string]apiserver.RESTStorage
+	client             *client.Client
+	portalNet          *net.IPNet
+
 	mux                   apiserver.Mux
 	handlerContainer      *restful.Container
 	rootWebService        *restful.WebService
 	enableLogsSupport     bool
 	enableUISupport       bool
+	enableSwaggerSupport  bool
 	apiPrefix             string
 	corsAllowedOriginList util.StringList
 	authenticator         authenticator.Request
@@ -222,7 +228,7 @@ func New(c *Config) *Master {
 	if c.KubeletClient == nil {
 		glog.Fatalf("master.New() called with config.KubeletClient == nil")
 	}
-	mx := http.NewServeMux()
+
 	m := &Master{
 		podRegistry:           etcd.NewRegistry(c.EtcdHelper, boundPodFactory),
 		controllerRegistry:    etcd.NewRegistry(c.EtcdHelper, nil),
@@ -233,11 +239,10 @@ func New(c *Config) *Master {
 		minionRegistry:        minionRegistry,
 		client:                c.Client,
 		portalNet:             c.PortalNet,
-		mux:                   mx,
-		handlerContainer:      NewHandlerContainer(mx),
 		rootWebService:        new(restful.WebService),
 		enableLogsSupport:     c.EnableLogsSupport,
 		enableUISupport:       c.EnableUISupport,
+		enableSwaggerSupport:  c.EnableSwaggerSupport,
 		apiPrefix:             c.APIPrefix,
 		corsAllowedOriginList: c.CorsAllowedOriginList,
 		authenticator:         c.Authenticator,
@@ -247,6 +252,16 @@ func New(c *Config) *Master {
 		readOnlyServer:  net.JoinHostPort(c.PublicAddress, strconv.Itoa(int(c.ReadOnlyPort))),
 		readWriteServer: net.JoinHostPort(c.PublicAddress, strconv.Itoa(int(c.ReadWritePort))),
 	}
+
+	if c.RestfulContainer != nil {
+		m.mux = c.RestfulContainer.ServeMux
+		m.handlerContainer = c.RestfulContainer
+	} else {
+		mux := http.NewServeMux()
+		m.mux = mux
+		m.handlerContainer = NewHandlerContainer(mux)
+	}
+
 	m.masterServices = util.NewRunner(m.serviceWriterLoop, m.roServiceWriterLoop)
 	m.init(c)
 	return m
@@ -377,7 +392,22 @@ func (m *Master) init(c *Config) {
 	// Install root web services
 	m.handlerContainer.Add(m.rootWebService)
 
-	// TODO: Make this optional?
+	// TODO: Make this optional?  Consumers of master depend on this currently.
+	m.Handler = handler
+
+	if m.enableSwaggerSupport {
+		m.InstallSwaggerAPI()
+	}
+
+	// TODO: Attempt clean shutdown?
+	m.masterServices.Start()
+}
+
+// InstallSwaggerAPI installs the /swaggerapi/ endpoint to allow schema discovery
+// and traversal.  It is optional to allow consumers of the Kubernetes master to
+// register their own web services into the Kubernetes mux prior to initialization
+// of swagger, so that other resource types show up in the documentation.
+func (m *Master) InstallSwaggerAPI() {
 	// Enable swagger UI and discovery API
 	swaggerConfig := swagger.Config{
 		WebServices: m.handlerContainer.RegisteredWebServices(),
@@ -388,11 +418,6 @@ func (m *Master) init(c *Config) {
 		//SwaggerFilePath: "/srv/apiserver/swagger/dist"
 	}
 	swagger.RegisterSwaggerService(swaggerConfig, m.handlerContainer)
-
-	m.Handler = handler
-
-	// TODO: Attempt clean shutdown?
-	m.masterServices.Start()
 }
 
 func (m *Master) getServersToValidate(c *Config) map[string]apiserver.Server {

pkg/standalone/standalone.go

@@ -87,15 +87,15 @@ func RunApiServer(cl *client.Client, etcdClient tools.EtcdClient, addr string, p
 			Client: http.DefaultClient,
 			Port:   10250,
 		},
-		EnableLogsSupport: false,
-		APIPrefix:         "/api",
-		Authorizer:        apiserver.NewAlwaysAllowAuthorizer(),
+		EnableLogsSupport:    false,
+		EnableSwaggerSupport: true,
+		APIPrefix:            "/api",
+		Authorizer:           apiserver.NewAlwaysAllowAuthorizer(),
 
 		ReadWritePort: port,
 		ReadOnlyPort:  port,
 		PublicAddress: addr,
 	})
-
 	handler.delegate = m.InsecureHandler
 
 	go http.ListenAndServe(fmt.Sprintf("%s:%d", addr, port), &handler)