executors: Unify go-plugin handshake

command/executor_plugin.go

@@ -8,6 +8,7 @@ import (
 	hclog "github.com/hashicorp/go-hclog"
 	"github.com/hashicorp/go-plugin"
 
+	"github.com/hashicorp/nomad/plugins/base"
 	"github.com/hashicorp/nomad/plugins/executor"
 )
 
@@ -42,7 +43,7 @@ func (e *ExecutorPluginCommand) Run(args []string) int {
 		return 1
 	}
 	plugin.Serve(&plugin.ServeConfig{
-		HandshakeConfig: executor.HandshakeConfig,
+		HandshakeConfig: base.Handshake,
 		Plugins: executor.GetPluginMap(
 			stdo,
 			hclog.LevelFromString(executorConfig.LogLevel),

plugins/drivers/utils/utils.go

@@ -78,7 +78,7 @@ func CreateExecutor(w io.Writer, level hclog.Level, driverConfig *base.ClientDri
 	config := &plugin.ClientConfig{
 		Cmd: exec.Command(bin, "executor", string(c)),
 	}
-	config.HandshakeConfig = pexecutor.HandshakeConfig
+	config.HandshakeConfig = base.Handshake
 	config.Plugins = pexecutor.GetPluginMap(w, level, executorConfig.FSIsolation)
 
 	if driverConfig != nil {
@@ -111,7 +111,7 @@ func CreateExecutor(w io.Writer, level hclog.Level, driverConfig *base.ClientDri
 
 // CreateExecutorWithConfig launches a plugin with a given plugin config
 func CreateExecutorWithConfig(config *plugin.ClientConfig, w io.Writer) (executor.Executor, *plugin.Client, error) {
-	config.HandshakeConfig = pexecutor.HandshakeConfig
+	config.HandshakeConfig = base.Handshake
 
 	// Setting this to DEBUG since the log level at the executor server process
 	// is already set, and this effects only the executor client.

plugins/executor/plugins.go

@@ -22,12 +22,6 @@ type ExecutorConfig struct {
 	FSIsolation bool
 }
 
-var HandshakeConfig = plugin.HandshakeConfig{
-	ProtocolVersion:  1,
-	MagicCookieKey:   "NOMAD_PLUGIN_MAGIC_COOKIE",
-	MagicCookieValue: "e4327c2e01eabfd75a8a67adb114fb34a757d57eee7728d857a8cec6e91a7255",
-}
-
 func GetPluginMap(w io.Writer, logLevel hclog.Level, fsIsolation bool) map[string]plugin.Plugin {
 	e := new(ExecutorPlugin)