allow to catch response headers

Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>

micro.go

@@ -1,6 +1,8 @@
 package main
 
 import (
+	"fmt"
+
 	"google.golang.org/protobuf/compiler/protogen"
 )
 
@@ -22,8 +24,10 @@ func (g *Generator) microGenerate(component string, plugin *protogen.Plugin, gen
 		gfile := plugin.NewGeneratedFile(gname, path)
 
 		gfile.P("// Code generated by protoc-gen-go-micro. DO NOT EDIT.")
-		gfile.P("// protoc-gen-go-micro version: " + versionComment)
-		gfile.P("// source: ", file.Proto.GetName())
+		gfile.P("// versions:")
+		gfile.P("// - protoc-gen-go-micro " + versionComment)
+		gfile.P("// - protoc              ", protocVersion(plugin))
+		gfile.P("// source: ", file.Desc.Path())
 		gfile.P()
 		gfile.P("package ", file.GoPackageName)
 		gfile.P()
@@ -50,3 +54,15 @@ func (g *Generator) microGenerate(component string, plugin *protogen.Plugin, gen
 
 	return nil
 }
+
+func protocVersion(plugin *protogen.Plugin) string {
+	v := plugin.Request.GetCompilerVersion()
+	if v == nil {
+		return "(unknown)"
+	}
+	var suffix string
+	if s := v.GetSuffix(); s != "" {
+		suffix = "-" + s
+	}
+	return fmt.Sprintf("v%d.%d.%d%s", v.GetMajor(), v.GetMinor(), v.GetPatch(), suffix)
+}