Revert "Enable POST method support for token fetch"

This reverts commit d2fcf67ded6d27b4ce6257bbd8b431720ba0120d.

Reverting due to https://bugs.launchpad.net/starlingx/+bug/1859686

Change-Id: If30034c4011162361c469072bd08c8e3b4975c33

registry-token-server/src/keystone/access.go

@@ -73,25 +73,6 @@ func (ac *accessController) Authorized(ctx context.Context, accessRecords ...aut
 	return auth.WithUser(ctx, auth.UserInfo{Name: username}), nil
 }
 
-// AuthenticateUser checks a given user:password credential by keystone.
-// If the check passes, nil is returned.
-func (ac *accessController) AuthenticateUser(username string, password string) error {
-
-	opts := gophercloud.AuthOptions{
-		IdentityEndpoint: ac.endpoint,
-		Username:         username,
-		Password:         password,
-		DomainID:         "default",
-	}
-
-	if _, err := openstack.AuthenticatedClient(opts); err != nil {
-		context.GetLogger(context.Background()).Errorf("error authenticating user %q: %v", username, err)
-		return auth.ErrAuthenticationFailure
-	}
-
-	return nil
-}
-
 // challenge implements the auth.Challenge interface.
 type challenge struct {
 	realm string
@@ -112,3 +93,4 @@ func (ch challenge) Error() string {
 func init() {
 	auth.Register("keystone", auth.InitFunc(newAccessController))
 }
+

registry-token-server/src/main.go

@@ -20,9 +20,9 @@ import (
 	"github.com/docker/distribution/context"
 	"github.com/docker/distribution/registry/api/errcode"
 	"github.com/docker/distribution/registry/auth"
+	_ "registry-token-server/keystone"
 	"github.com/docker/libtrust"
 	"github.com/gorilla/mux"
-	_ "registry-token-server/keystone"
 )
 
 var (