Bump plugin client version (#1319)

* Bump plugin client version

Signed-off-by: Carlisia <carlisiac@vmware.com>

pkg/plugin/clientmgmt/client_builder.go

@@ -60,7 +60,7 @@ func newLogrusAdapter(pluginLogger logrus.FieldLogger, logLevel logrus.Level) *l
 
 func (b *clientBuilder) clientConfig() *hcplugin.ClientConfig {
 	return &hcplugin.ClientConfig{
-		HandshakeConfig:  framework.Handshake,
+		HandshakeConfig:  framework.Handshake(),
 		AllowedProtocols: []hcplugin.Protocol{hcplugin.ProtocolGRPC},
 		Plugins: map[string]hcplugin.Plugin{
 			string(framework.PluginKindBackupItemAction):  framework.NewBackupItemActionPlugin(framework.ClientLogger(b.clientLogger)),

pkg/plugin/clientmgmt/client_builder_test.go

@@ -49,7 +49,7 @@ func TestClientConfig(t *testing.T) {
 	cb := newClientBuilder("velero", logger, logLevel)
 
 	expected := &hcplugin.ClientConfig{
-		HandshakeConfig:  framework.Handshake,
+		HandshakeConfig:  framework.Handshake(),
 		AllowedProtocols: []hcplugin.Protocol{hcplugin.ProtocolGRPC},
 		Plugins: map[string]hcplugin.Plugin{
 			string(framework.PluginKindBackupItemAction):  framework.NewBackupItemActionPlugin(framework.ClientLogger(logger)),

pkg/plugin/framework/handshake.go

@@ -0,0 +1,32 @@
+/*
+Copyright 2019 the Velero contributors.
+
+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 framework
+
+import plugin "github.com/hashicorp/go-plugin"
+
+// Handshake returns the configuration information that allows go-plugin clients and servers to perform a handshake.
+func Handshake() plugin.HandshakeConfig {
+	return plugin.HandshakeConfig{
+		// The ProtocolVersion is the version that must match between Velero framework
+		// and Velero client plugins. This should be bumped whenever a change happens in
+		// one or the other that makes it so that they can't safely communicate.
+		ProtocolVersion: 2,
+
+		MagicCookieKey:   "VELERO_PLUGIN",
+		MagicCookieValue: "hello",
+	}
+}

pkg/plugin/framework/server.go

@@ -28,16 +28,6 @@ import (
 	"github.com/heptio/velero/pkg/util/logging"
 )
 
-// Handshake is configuration information that allows go-plugin clients and servers to perform a handshake.
-//
-// TODO(ncdc): this should probably be a function so it can't be mutated, and we should probably move it to
-// handshake.go.
-var Handshake = plugin.HandshakeConfig{
-	ProtocolVersion:  1,
-	MagicCookieKey:   "ARK_PLUGIN",
-	MagicCookieValue: "hello",
-}
-
 // Server serves registered plugin implementations.
 type Server interface {
 	// BindFlags defines the plugin server's command-line flags
@@ -188,7 +178,7 @@ func (s *server) Serve() {
 	pluginLister := NewPluginLister(pluginIdentifiers...)
 
 	plugin.Serve(&plugin.ServeConfig{
-		HandshakeConfig: Handshake,
+		HandshakeConfig: Handshake(),
 		Plugins: map[string]plugin.Plugin{
 			string(PluginKindBackupItemAction):  s.backupItemAction,
 			string(PluginKindVolumeSnapshotter): s.volumeSnapshotter,