add discovery client

cmd/kube-controller-manager/app/controllermanager.go

@@ -292,7 +292,7 @@ func (s *CMServer) Run(_ []string) error {
 	}
 	versions := &unversioned.APIVersions{Versions: versionStrings}
 
-	resourceMap, err := client.SupportedResources(kubeClient, kubeconfig)
+	resourceMap, err := kubeClient.Discovery().ServerResources()
 	if err != nil {
 		glog.Fatalf("Failed to get supported resources from server: %v", err)
 	}

pkg/client/unversioned/client.go

@@ -52,7 +52,7 @@ type Interface interface {
 	ComponentStatusesInterface
 	SwaggerSchemaInterface
 	Extensions() ExtensionsInterface
-	ResourcesInterface
+	Discovery() DiscoveryInterface
 }
 
 func (c *Client) ReplicationControllers(namespace string) ReplicationControllerInterface {
@@ -120,11 +120,6 @@ type VersionInterface interface {
 	ServerAPIVersions() (*unversioned.APIVersions, error)
 }
 
-// ResourcesInterface has methods for obtaining supported resources on the API server
-type ResourcesInterface interface {
-	SupportedResourcesForGroupVersion(groupVersion string) (*unversioned.APIResourceList, error)
-}
-
 // APIStatus is exposed by errors that can be converted to an api.Status object
 // for finer grained details.
 type APIStatus interface {
@@ -135,6 +130,8 @@ type APIStatus interface {
 type Client struct {
 	*RESTClient
 	*ExtensionsClient
+	// TODO: remove this when we re-structure pkg/client.
+	*DiscoveryClient
 }
 
 // ServerVersion retrieves and parses the server's version.
@@ -151,42 +148,6 @@ func (c *Client) ServerVersion() (*version.Info, error) {
 	return &info, nil
 }
 
-// SupportedResourcesForGroupVersion retrieves the list of resources supported by the API server for a group version.
-func (c *Client) SupportedResourcesForGroupVersion(groupVersion string) (*unversioned.APIResourceList, error) {
-	var prefix string
-	if groupVersion == "v1" {
-		prefix = "/api"
-	} else {
-		prefix = "/apis"
-	}
-	body, err := c.Get().AbsPath(prefix, groupVersion).Do().Raw()
-	if err != nil {
-		return nil, err
-	}
-	resources := unversioned.APIResourceList{}
-	if err := json.Unmarshal(body, &resources); err != nil {
-		return nil, err
-	}
-	return &resources, nil
-}
-
-// SupportedResources gets all supported resources for all group versions.  The key in the map is an API groupVersion.
-func SupportedResources(c Interface, cfg *Config) (map[string]*unversioned.APIResourceList, error) {
-	apis, err := ServerAPIVersions(cfg)
-	if err != nil {
-		return nil, err
-	}
-	result := map[string]*unversioned.APIResourceList{}
-	for _, groupVersion := range apis {
-		resources, err := c.SupportedResourcesForGroupVersion(groupVersion)
-		if err != nil {
-			return nil, err
-		}
-		result[groupVersion] = resources
-	}
-	return result, nil
-}
-
 // ServerAPIVersions retrieves and parses the list of API versions the server supports.
 func (c *Client) ServerAPIVersions() (*unversioned.APIVersions, error) {
 	body, err := c.Get().UnversionedPath("").Do().Raw()
@@ -288,3 +249,7 @@ func IsTimeout(err error) bool {
 func (c *Client) Extensions() ExtensionsInterface {
 	return c.ExtensionsClient
 }
+
+func (c *Client) Discovery() DiscoveryInterface {
+	return c.DiscoveryClient
+}

pkg/client/unversioned/client_test.go

@@ -352,7 +352,7 @@ func TestGetServerResources(t *testing.T) {
 	}))
 	client := NewOrDie(&Config{Host: server.URL})
 	for _, test := range tests {
-		got, err := client.SupportedResourcesForGroupVersion(test.request)
+		got, err := client.Discovery().ServerResourcesForGroupVersion(test.request)
 		if test.expectErr {
 			if err == nil {
 				t.Error("unexpected non-error")
@@ -368,7 +368,7 @@ func TestGetServerResources(t *testing.T) {
 		}
 	}
 
-	resourceMap, err := SupportedResources(client, &Config{Host: server.URL})
+	resourceMap, err := client.Discovery().ServerResources()
 	if err != nil {
 		t.Errorf("unexpected error: %v", err)
 	}

pkg/client/unversioned/discovery_client.go

@@ -0,0 +1,175 @@
+/*
+Copyright 2015 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 unversioned
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/url"
+
+	"k8s.io/kubernetes/pkg/api/unversioned"
+)
+
+// DiscoveryInterface holds the methods that discover server-supported API groups,
+// versions and resources.
+type DiscoveryInterface interface {
+	ServerGroupsInterface
+	ServerResourcesInterface
+}
+
+// GroupsInterface has methods for obtaining supported groups on the API server
+type ServerGroupsInterface interface {
+	// ServerGroups returns the supported groups, with information like supported versions and the
+	// preferred version.
+	ServerGroups() (*unversioned.APIGroupList, error)
+}
+
+// ServerResourcesInterface has methods for obtaining supported resources on the API server
+type ServerResourcesInterface interface {
+	// ServerResourcesForGroupVersion returns the supported resources for a group and version.
+	ServerResourcesForGroupVersion(groupVersion string) (*unversioned.APIResourceList, error)
+	// ServerResources returns the supported resources for all groups and versions.
+	ServerResources() (map[string]*unversioned.APIResourceList, error)
+}
+
+// DiscoveryClient implements the functions that dicovery server-supported API groups,
+// versions and resources.
+type DiscoveryClient struct {
+	httpClient HTTPClient
+	baseURL    url.URL
+}
+
+// Convert unversioned.APIVersions to unversioned.APIGroup. APIVersions is used by legacy v1, so
+// group would be "".
+func apiVersionsToAPIGroup(apiVersions *unversioned.APIVersions) (apiGroup unversioned.APIGroup) {
+	groupVersions := []unversioned.GroupVersion{}
+	for _, version := range apiVersions.Versions {
+		groupVersion := unversioned.GroupVersion{
+			GroupVersion: version,
+			Version:      version,
+		}
+		groupVersions = append(groupVersions, groupVersion)
+	}
+	apiGroup.Versions = groupVersions
+	// There should be only one groupVersion returned at /api
+	apiGroup.PreferredVersion = groupVersions[0]
+	return
+}
+
+func (d *DiscoveryClient) get(url string) (resp *http.Response, err error) {
+	req, err := http.NewRequest("GET", url, nil)
+	if err != nil {
+		return nil, err
+	}
+	return d.httpClient.Do(req)
+}
+
+// APIGroups returns the supported groups, with information like supported versions and the
+// preferred version.
+func (d *DiscoveryClient) ServerGroups() (apiGroupList *unversioned.APIGroupList, err error) {
+	// Get the groupVersions exposed at /api
+	url := d.baseURL
+	url.Path = "/api"
+	resp, err := d.get(url.String())
+	if err != nil {
+		return nil, err
+	}
+	var v unversioned.APIVersions
+	defer resp.Body.Close()
+	err = json.NewDecoder(resp.Body).Decode(&v)
+	if err != nil {
+		return nil, fmt.Errorf("unexpected error: %v", err)
+	}
+	apiGroup := apiVersionsToAPIGroup(&v)
+
+	// Get the groupVersions exposed at /apis
+	url.Path = "/apis"
+	resp2, err := d.get(url.String())
+	if err != nil {
+		return nil, err
+	}
+	defer resp2.Body.Close()
+	apiGroupList = &unversioned.APIGroupList{}
+	if err = json.NewDecoder(resp2.Body).Decode(&apiGroupList); err != nil {
+		return nil, fmt.Errorf("unexpected error: %v", err)
+	}
+
+	// append the group retrieved from /api to the list
+	apiGroupList.Groups = append(apiGroupList.Groups, apiGroup)
+	return apiGroupList, nil
+}
+
+// APIResourcesForGroup returns the supported resources for a group and version.
+func (d *DiscoveryClient) ServerResourcesForGroupVersion(groupVersion string) (resources *unversioned.APIResourceList, err error) {
+	url := d.baseURL
+	if groupVersion == "v1" {
+		url.Path = "/api/" + groupVersion
+	} else {
+		url.Path = "/apis/" + groupVersion
+	}
+	resp, err := d.get(url.String())
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+	resources = &unversioned.APIResourceList{}
+	if err = json.NewDecoder(resp.Body).Decode(resources); err != nil {
+		return nil, fmt.Errorf("unexpected error: %v", err)
+	}
+	return resources, nil
+}
+
+// APIResources returns the supported resources for all groups and versions.
+func (d *DiscoveryClient) ServerResources() (map[string]*unversioned.APIResourceList, error) {
+	apiGroups, err := d.ServerGroups()
+	if err != nil {
+		return nil, err
+	}
+	groupVersions := extractGroupVersions(apiGroups)
+	result := map[string]*unversioned.APIResourceList{}
+	for _, groupVersion := range groupVersions {
+		resources, err := d.ServerResourcesForGroupVersion(groupVersion)
+		if err != nil {
+			return nil, err
+		}
+		result[groupVersion] = resources
+	}
+	return result, nil
+}
+
+func setDiscoveryDefaults(config *Config) error {
+	config.Prefix = ""
+	config.Version = ""
+	return nil
+}
+
+// NewDiscoveryClient creates a new DiscoveryClient for the given config. This client
+// can be used to discover supported resources in the API server.
+func NewDiscoveryClient(c *Config) (*DiscoveryClient, error) {
+	config := *c
+	if err := setDiscoveryDefaults(&config); err != nil {
+		return nil, err
+	}
+	transport, err := TransportFor(c)
+	if err != nil {
+		return nil, err
+	}
+	client := &http.Client{Transport: transport}
+	baseURL, err := defaultServerUrlFor(c)
+	return &DiscoveryClient{client, *baseURL}, nil
+}

pkg/client/unversioned/helper.go

@@ -146,15 +146,22 @@ func New(c *Config) (*Client, error) {
 		return nil, err
 	}
 
+	discoveryConfig := *c
+	discoveryClient, err := NewDiscoveryClient(&discoveryConfig)
+	if err != nil {
+		return nil, err
+	}
+
 	if _, err := latest.Group("extensions"); err != nil {
-		return &Client{RESTClient: client, ExtensionsClient: nil}, nil
+		return &Client{RESTClient: client, ExtensionsClient: nil, DiscoveryClient: discoveryClient}, nil
 	}
 	experimentalConfig := *c
 	experimentalClient, err := NewExtensions(&experimentalConfig)
 	if err != nil {
 		return nil, err
 	}
-	return &Client{RESTClient: client, ExtensionsClient: experimentalClient}, nil
+
+	return &Client{RESTClient: client, ExtensionsClient: experimentalClient, DiscoveryClient: discoveryClient}, nil
 }
 
 // MatchesServerVersion queries the server to compares the build version

pkg/client/unversioned/testclient/testclient.go

@@ -61,7 +61,7 @@ type Fake struct {
 	// ProxyReactionChain is the list of proxy reactors that will be attempted for every request in the order they are tried
 	ProxyReactionChain []ProxyReactor
 
-	Resources []unversioned.APIResourceList
+	Resources map[string]*unversioned.APIResourceList
 }
 
 // Reactor is an interface to allow the composition of reaction functions.
@@ -274,18 +274,8 @@ func (c *Fake) Extensions() client.ExtensionsInterface {
 	return &FakeExperimental{c}
 }
 
-func (c *Fake) SupportedResourcesForGroupVersion(version string) (*unversioned.APIResourceList, error) {
+func (c *Fake) Discovery() client.DiscoveryInterface {
-	action := ActionImpl{
+	return &FakeDiscovery{c}
-		Verb:     "get",
-		Resource: "resource",
-	}
-	c.Invokes(action, nil)
-	for _, resource := range c.Resources {
-		if resource.GroupVersion == version {
-			return &resource, nil
-		}
-	}
-	return nil, nil
 }
 
 func (c *Fake) ServerVersion() (*version.Info, error) {
@@ -348,3 +338,29 @@ func (c *FakeExperimental) Jobs(namespace string) client.JobInterface {
 func (c *FakeExperimental) Ingress(namespace string) client.IngressInterface {
 	return &FakeIngress{Fake: c, Namespace: namespace}
 }
+
+type FakeDiscovery struct {
+	*Fake
+}
+
+func (c *FakeDiscovery) ServerResourcesForGroupVersion(groupVersion string) (*unversioned.APIResourceList, error) {
+	action := ActionImpl{
+		Verb:     "get",
+		Resource: "resource",
+	}
+	c.Invokes(action, nil)
+	return c.Resources[groupVersion], nil
+}
+
+func (c *FakeDiscovery) ServerResources() (map[string]*unversioned.APIResourceList, error) {
+	action := ActionImpl{
+		Verb:     "get",
+		Resource: "resource",
+	}
+	c.Invokes(action, nil)
+	return c.Resources, nil
+}
+
+func (c *FakeDiscovery) ServerGroups() (*unversioned.APIGroupList, error) {
+	return nil, nil
+}

pkg/controller/namespace/namespace_controller.go

@@ -194,7 +194,7 @@ func deleteAllContent(kubeClient client.Interface, versions *unversioned.APIVers
 	}
 	// If experimental mode, delete all experimental resources for the namespace.
 	if containsVersion(versions, "extensions/v1beta1") {
-		resources, err := kubeClient.SupportedResourcesForGroupVersion("extensions/v1beta1")
+		resources, err := kubeClient.Discovery().ServerResourcesForGroupVersion("extensions/v1beta1")
 		if err != nil {
 			return estimate, err
 		}

pkg/controller/namespace/namespace_controller_test.go

@@ -95,8 +95,8 @@ func testSyncNamespaceThatIsTerminating(t *testing.T, versions *unversioned.APIV
 		for _, resource := range []string{"daemonsets", "deployments", "jobs", "horizontalpodautoscalers", "ingress"} {
 			resources = append(resources, unversioned.APIResource{Name: resource})
 		}
-		mockClient.Resources = []unversioned.APIResourceList{
+		mockClient.Resources = map[string]*unversioned.APIResourceList{
-			{
+			"extensions/v1beta1": {
 				GroupVersion: "extensions/v1beta1",
 				APIResources: resources,
 			},