add docker logger to separate main

drivers/docker/cmd/main.go

@@ -1,12 +1,34 @@
 package main
 
 import (
+	"os"
+
 	log "github.com/hashicorp/go-hclog"
+	plugin "github.com/hashicorp/go-plugin"
 	"github.com/hashicorp/nomad/drivers/docker"
+	"github.com/hashicorp/nomad/drivers/docker/docklog"
 	"github.com/hashicorp/nomad/plugins"
+	"github.com/hashicorp/nomad/plugins/base"
 )
 
 func main() {
+
+	if len(os.Args) > 1 {
+		// Detect if we are being launched as a docker logging plugin
+		switch os.Args[1] {
+		case docklog.PluginName:
+			plugin.Serve(&plugin.ServeConfig{
+				HandshakeConfig: base.Handshake,
+				Plugins: map[string]plugin.Plugin{
+					docklog.PluginName: docklog.NewPlugin(docklog.NewDockerLogger(log.Default().Named(docklog.PluginName))),
+				},
+				GRPCServer: plugin.DefaultGRPCServer,
+			})
+
+			return
+		}
+	}
+
 	// Serve the plugin
 	plugins.Serve(factory)
 }