Make MapperProvider multi-cluster by default

Default options.MapperProvider to an implementation that defaults to
/clusters/*, so API discovery (i.e. REST mapping) will work.

Signed-off-by: Andy Goldstein <andy.goldstein@redhat.com>

Author: ncdc

pkg/kcp/wrappers.go

@@ -18,9 +18,12 @@ package kcp
 
 import (
 	"net/http"
+	"strings"
 
+	"k8s.io/apimachinery/pkg/api/meta"
 	"k8s.io/client-go/rest"
 	k8scache "k8s.io/client-go/tools/cache"
+	"sigs.k8s.io/controller-runtime/pkg/client/apiutil"
 
 	kcpcache "github.com/kcp-dev/apimachinery/pkg/cache"
 	kcpclient "github.com/kcp-dev/apimachinery/pkg/client"
@@ -38,10 +41,22 @@ func NewClusterAwareManager(cfg *rest.Config, options ctrl.Options) (manager.Man
 	if options.NewCache == nil {
 		options.NewCache = NewClusterAwareCache
 	}
+
 	if options.NewClient == nil {
 		options.NewClient = NewClusterAwareClient
 	}
 
+	if options.MapperProvider == nil {
+		options.MapperProvider = func(c *rest.Config) (meta.RESTMapper, error) {
+			mapperCfg := rest.CopyConfig(c)
+			if !strings.HasSuffix(mapperCfg.Host, "/clusters/*") {
+				mapperCfg.Host += "/clusters/*"
+			}
+
+			return apiutil.NewDynamicRESTMapper(mapperCfg)
+		}
+	}
+
 	return ctrl.NewManager(cfg, options)
 }