clean up client version negotiation to handle no legacy API

2025-11-03 11:48:15 +00:00 · 2016-10-28 13:01:32 -04:00
parent 1cba31af40
commit bae940df5c
3 changed files with 104 additions and 106 deletions
--- a/pkg/client/typed/discovery/helper.go
+++ b/pkg/client/typed/discovery/helper.go
@@ -20,7 +20,6 @@ import (
 	"fmt"

 	"k8s.io/kubernetes/pkg/api/unversioned"
-	"k8s.io/kubernetes/pkg/client/restclient"
 	"k8s.io/kubernetes/pkg/util/sets"
 	"k8s.io/kubernetes/pkg/version"
 	// Import solely to initialize client auth plugins.
@@ -30,14 +29,7 @@ import (
 // MatchesServerVersion queries the server to compares the build version
 // (git hash) of the client with the server's build version. It returns an error
 // if it failed to contact the server or if the versions are not an exact match.
-func MatchesServerVersion(client DiscoveryInterface, c *restclient.Config) error {
-	var err error
-	if client == nil {
-		client, err = NewDiscoveryClientForConfig(c)
-		if err != nil {
-			return err
-		}
-	}
+func MatchesServerVersion(client DiscoveryInterface) error {
 	cVer := version.Get()
 	sVer, err := client.ServerVersion()
 	if err != nil {
@@ -55,19 +47,9 @@ func MatchesServerVersion(client DiscoveryInterface, c *restclient.Config) error
 // a version that both client and server support.
 // - If no version is provided, try registered client versions in order of
 //   preference.
-// - If version is provided, but not default config (explicitly requested via
-//   commandline flag), and is unsupported by the server, print a warning to
-//   stderr and try client's registered versions in order of preference.
-// - If version is config default, and the server does not support it,
+// - If version is provided and the server does not support it,
 //   return an error.
-func NegotiateVersion(client DiscoveryInterface, c *restclient.Config, requestedGV *unversioned.GroupVersion, clientRegisteredGVs []unversioned.GroupVersion) (*unversioned.GroupVersion, error) {
-	var err error
-	if client == nil {
-		client, err = NewDiscoveryClientForConfig(c)
-		if err != nil {
-			return nil, err
-		}
-	}
+func NegotiateVersion(client DiscoveryInterface, requiredGV *unversioned.GroupVersion, clientRegisteredGVs []unversioned.GroupVersion) (*unversioned.GroupVersion, error) {
 	clientVersions := sets.String{}
 	for _, gv := range clientRegisteredGVs {
 		clientVersions.Insert(gv.String())
@@ -84,37 +66,23 @@ func NegotiateVersion(client DiscoveryInterface, c *restclient.Config, requested
 		serverVersions.Insert(v)
 	}

-	// If no version requested, use config version (may also be empty).
-	// make a copy of the original so we don't risk mutating input here or in the returned value
-	var preferredGV *unversioned.GroupVersion
-	switch {
-	case requestedGV != nil:
-		t := *requestedGV
-		preferredGV = &t
-	case c.GroupVersion != nil:
-		t := *c.GroupVersion
-		preferredGV = &t
-	}
-
 	// If version explicitly requested verify that both client and server support it.
 	// If server does not support warn, but try to negotiate a lower version.
-	if preferredGV != nil {
-		if !clientVersions.Has(preferredGV.String()) {
-			return nil, fmt.Errorf("client does not support API version %q; client supported API versions: %v", preferredGV, clientVersions)
+	if requiredGV != nil {
+		if !clientVersions.Has(requiredGV.String()) {
+			return nil, fmt.Errorf("client does not support API version %q; client supported API versions: %v", requiredGV, clientVersions)

 		}
 		// If the server supports no versions, then we should just use the preferredGV
 		// This can happen because discovery fails due to 403 Forbidden errors
 		if len(serverVersions) == 0 {
-			return preferredGV, nil
+			return requiredGV, nil
 		}
-		if serverVersions.Has(preferredGV.String()) {
-			return preferredGV, nil
+		if serverVersions.Has(requiredGV.String()) {
+			return requiredGV, nil
 		}
 		// If we are using an explicit config version the server does not support, fail.
-		if (c.GroupVersion != nil) && (*preferredGV == *c.GroupVersion) {
-			return nil, fmt.Errorf("server does not support API version %q", preferredGV)
-		}
+		return nil, fmt.Errorf("server does not support API version %q", requiredGV)
 	}

 	for _, clientGV := range clientRegisteredGVs {
@@ -130,6 +98,12 @@ func NegotiateVersion(client DiscoveryInterface, c *restclient.Config, requested
 			return &t, nil
 		}
 	}
+
+	// if we have no server versions and we have no required version, choose the first clientRegisteredVersion
+	if len(serverVersions) == 0 && len(clientRegisteredGVs) > 0 {
+		return &clientRegisteredGVs[0], nil
+	}
+
 	return nil, fmt.Errorf("failed to negotiate an api version; server supports: %v, client supports: %v",
 		serverVersions, clientVersions)
 }
--- a/pkg/client/typed/discovery/helper_blackbox_test.go
+++ b/pkg/client/typed/discovery/helper_blackbox_test.go
@@ -47,19 +47,16 @@ func objBody(object interface{}) io.ReadCloser {
 func TestNegotiateVersion(t *testing.T) {
 	tests := []struct {
 		name            string
-		version         *uapi.GroupVersion
+		requiredVersion *uapi.GroupVersion
 		expectedVersion *uapi.GroupVersion
 		serverVersions  []string
 		clientVersions  []uapi.GroupVersion
-		config          *restclient.Config
 		expectErr       func(err error) bool
 		sendErr         error
 		statusCode      int
 	}{
 		{
 			name:            "server supports client default",
-			version:         &uapi.GroupVersion{Version: "version1"},
-			config:          &restclient.Config{},
 			serverVersions:  []string{"version1", registered.GroupOrDie(api.GroupName).GroupVersion.String()},
 			clientVersions:  []uapi.GroupVersion{{Version: "version1"}, registered.GroupOrDie(api.GroupName).GroupVersion},
 			expectedVersion: &uapi.GroupVersion{Version: "version1"},
@@ -67,8 +64,6 @@ func TestNegotiateVersion(t *testing.T) {
 		},
 		{
 			name:            "server falls back to client supported",
-			version:         &registered.GroupOrDie(api.GroupName).GroupVersion,
-			config:          &restclient.Config{},
 			serverVersions:  []string{"version1"},
 			clientVersions:  []uapi.GroupVersion{{Version: "version1"}, registered.GroupOrDie(api.GroupName).GroupVersion},
 			expectedVersion: &uapi.GroupVersion{Version: "version1"},
@@ -76,23 +71,30 @@ func TestNegotiateVersion(t *testing.T) {
 		},
 		{
 			name:            "explicit version supported",
-			config:          &restclient.Config{ContentConfig: restclient.ContentConfig{GroupVersion: &registered.GroupOrDie(api.GroupName).GroupVersion}},
+			requiredVersion: &uapi.GroupVersion{Version: "v1"},
 			serverVersions:  []string{"/version1", registered.GroupOrDie(api.GroupName).GroupVersion.String()},
 			clientVersions:  []uapi.GroupVersion{{Version: "version1"}, registered.GroupOrDie(api.GroupName).GroupVersion},
-			expectedVersion: &registered.GroupOrDie(api.GroupName).GroupVersion,
+			expectedVersion: &uapi.GroupVersion{Version: "v1"},
 			statusCode:      http.StatusOK,
 		},
 		{
-			name:           "explicit version not supported",
-			config:         &restclient.Config{ContentConfig: restclient.ContentConfig{GroupVersion: &registered.GroupOrDie(api.GroupName).GroupVersion}},
-			serverVersions: []string{"version1"},
-			clientVersions: []uapi.GroupVersion{{Version: "version1"}, registered.GroupOrDie(api.GroupName).GroupVersion},
-			expectErr:      func(err error) bool { return strings.Contains(err.Error(), `server does not support API version "v1"`) },
-			statusCode:     http.StatusOK,
+			name:            "explicit version not supported on server",
+			requiredVersion: &uapi.GroupVersion{Version: "v1"},
+			serverVersions:  []string{"version1"},
+			clientVersions:  []uapi.GroupVersion{{Version: "version1"}, registered.GroupOrDie(api.GroupName).GroupVersion},
+			expectErr:       func(err error) bool { return strings.Contains(err.Error(), `server does not support API version "v1"`) },
+			statusCode:      http.StatusOK,
+		},
+		{
+			name:            "explicit version not supported on client",
+			requiredVersion: &uapi.GroupVersion{Version: "v1"},
+			serverVersions:  []string{"v1"},
+			clientVersions:  []uapi.GroupVersion{{Version: "version1"}},
+			expectErr:       func(err error) bool { return strings.Contains(err.Error(), `client does not support API version "v1"`) },
+			statusCode:      http.StatusOK,
 		},
 		{
 			name:           "connection refused error",
-			config:         &restclient.Config{ContentConfig: restclient.ContentConfig{GroupVersion: &registered.GroupOrDie(api.GroupName).GroupVersion}},
 			serverVersions: []string{"version1"},
 			clientVersions: []uapi.GroupVersion{{Version: "version1"}, registered.GroupOrDie(api.GroupName).GroupVersion},
 			sendErr:        errors.New("connection refused"),
@@ -101,25 +103,21 @@ func TestNegotiateVersion(t *testing.T) {
 		},
 		{
 			name:            "discovery fails due to 403 Forbidden errors and thus serverVersions is empty, use default GroupVersion",
-			config:          &restclient.Config{ContentConfig: restclient.ContentConfig{GroupVersion: &registered.GroupOrDie(api.GroupName).GroupVersion}},
 			clientVersions:  []uapi.GroupVersion{{Version: "version1"}, registered.GroupOrDie(api.GroupName).GroupVersion},
-			expectedVersion: &registered.GroupOrDie(api.GroupName).GroupVersion,
+			expectedVersion: &uapi.GroupVersion{Version: "version1"},
 			statusCode:      http.StatusForbidden,
 		},
 		{
 			name:            "discovery fails due to 404 Not Found errors and thus serverVersions is empty, use requested GroupVersion",
-			version:         &uapi.GroupVersion{Version: "version1"},
-			config:          &restclient.Config{ContentConfig: restclient.ContentConfig{GroupVersion: &registered.GroupOrDie(api.GroupName).GroupVersion}},
+			requiredVersion: &uapi.GroupVersion{Version: "version1"},
 			clientVersions:  []uapi.GroupVersion{{Version: "version1"}, registered.GroupOrDie(api.GroupName).GroupVersion},
 			expectedVersion: &uapi.GroupVersion{Version: "version1"},
 			statusCode:      http.StatusNotFound,
 		},
 		{
-			name:           "discovery fails due to 403 Forbidden errors and thus serverVersions is empty, no fallback GroupVersion",
-			config:         &restclient.Config{},
-			clientVersions: []uapi.GroupVersion{{Version: "version1"}, registered.GroupOrDie(api.GroupName).GroupVersion},
-			expectErr:      func(err error) bool { return strings.Contains(err.Error(), "failed to negotiate an api version;") },
-			statusCode:     http.StatusForbidden,
+			name:       "discovery fails due to 403 Forbidden errors and thus serverVersions is empty, no fallback GroupVersion",
+			expectErr:  func(err error) bool { return strings.Contains(err.Error(), "failed to negotiate an api version;") },
+			statusCode: http.StatusForbidden,
 		},
 	}

@@ -139,9 +137,9 @@ func TestNegotiateVersion(t *testing.T) {
 				return &http.Response{StatusCode: test.statusCode, Header: header, Body: objBody(&uapi.APIVersions{Versions: test.serverVersions})}, nil
 			}),
 		}
-		c := discovery.NewDiscoveryClientForConfigOrDie(test.config)
+		c := discovery.NewDiscoveryClientForConfigOrDie(&restclient.Config{})
 		c.RESTClient().(*restclient.RESTClient).Client = fakeClient.Client
-		response, err := discovery.NegotiateVersion(c, test.config, test.version, test.clientVersions)
+		response, err := discovery.NegotiateVersion(c, test.requiredVersion, test.clientVersions)
 		if err == nil && test.expectErr != nil {
 			t.Errorf("expected error, got nil for [%s].", test.name)
 		}