Adds kn revision delete command

docs/cmd/kn_revision.md

@@ -22,6 +22,7 @@ Revision command group
 ### SEE ALSO
 
 * [kn](kn.md)	 - Knative client
+* [kn revision delete](kn_revision_delete.md)	 - Delete a revision.
 * [kn revision describe](kn_revision_describe.md)	 - Describe revisions.
 * [kn revision list](kn_revision_list.md)	 - List available revisions.
 

docs/cmd/kn_revision_delete.md

@@ -0,0 +1,38 @@
+## kn revision delete
+
+Delete a revision.
+
+### Synopsis
+
+Delete a revision.
+
+```
+kn revision delete NAME [flags]
+```
+
+### Examples
+
+```
+
+  # Delete a revision 'svc1-abcde' in default namespace
+  kn revision delete svc1-abcde
+```
+
+### Options
+
+```
+  -h, --help               help for delete
+  -n, --namespace string   List the requested object(s) in given namespace.
+```
+
+### Options inherited from parent commands
+
+```
+      --config string       config file (default is $HOME/.kn/config.yaml)
+      --kubeconfig string   kubectl config file (default is $HOME/.kube/config)
+```
+
+### SEE ALSO
+
+* [kn revision](kn_revision.md)	 - Revision command group
+

pkg/kn/commands/revision/delete.go

@@ -0,0 +1,60 @@
+// Copyright © 2019 The Knative Authors
+//
+// 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 revision
+
+import (
+	"errors"
+	"fmt"
+
+	"github.com/knative/client/pkg/kn/commands"
+	"github.com/spf13/cobra"
+	v1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+)
+
+// NewRevisionDeleteCommand represent 'revision delete' command
+func NewRevisionDeleteCommand(p *commands.KnParams) *cobra.Command {
+	RevisionDeleteCommand := &cobra.Command{
+		Use:   "delete NAME",
+		Short: "Delete a revision.",
+		Example: `
+  # Delete a revision 'svc1-abcde' in default namespace
+  kn revision delete svc1-abcde`,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			if len(args) != 1 {
+				return errors.New("requires the revision name.")
+			}
+			client, err := p.ServingFactory()
+			if err != nil {
+				return err
+			}
+			namespace, err := p.GetNamespace(cmd)
+			if err != nil {
+				return err
+			}
+
+			err = client.Revisions(namespace).Delete(
+				args[0],
+				&v1.DeleteOptions{},
+			)
+			if err != nil {
+				return err
+			}
+			fmt.Fprintf(cmd.OutOrStdout(), "Revision '%s' successfully deleted in namespace '%s'.\n", args[0], namespace)
+			return nil
+		},
+	}
+	commands.AddNamespaceFlags(RevisionDeleteCommand.Flags(), false)
+	return RevisionDeleteCommand
+}

pkg/kn/commands/revision/revision.go

@@ -26,5 +26,6 @@ func NewRevisionCommand(p *commands.KnParams) *cobra.Command {
 	}
 	revisionCmd.AddCommand(NewRevisionListCommand(p))
 	revisionCmd.AddCommand(NewRevisionDescribeCommand(p))
+	revisionCmd.AddCommand(NewRevisionDeleteCommand(p))
 	return revisionCmd
 }