Merge pull request #9522 from brendandburns/friction

Add a better message if the user doesn't specify a resource type.

pkg/kubectl/cmd/get.go

@@ -17,6 +17,7 @@ limitations under the License.
 package cmd
 
 import (
+	"errors"
 	"fmt"
 	"io"
 
@@ -94,6 +95,23 @@ func RunGet(f *cmdutil.Factory, out io.Writer, cmd *cobra.Command, args []string
 		return err
 	}
 
+	if len(args) == 0 {
+		fmt.Fprint(out, `
+You must specify the type of resource to get. Valid resource types include:
+   * pods (aka 'po')
+   * replicationcontrollers (aka 'rc')
+   * services
+   * nodes (aka 'no')
+   * events (aka 'ev')
+   * secrets
+   * limits
+   * persistentVolumes (aka 'pv')
+   * persistentVolumeClaims (aka 'pvc')
+   * quota
+`)
+		return errors.New("Required resource not specified.")
+	}
+
 	// handle watch separately since we cannot watch multiple resource types
 	isWatch, isWatchOnly := cmdutil.GetFlagBool(cmd, "watch"), cmdutil.GetFlagBool(cmd, "watch-only")
 	if isWatch || isWatchOnly {