diff --git a/src/compiler/cpp_generator.cc b/src/compiler/cpp_generator.cc
index 2908b639f39..44578e3fe1e 100644
--- a/src/compiler/cpp_generator.cc
+++ b/src/compiler/cpp_generator.cc
@@ -40,6 +40,9 @@
 namespace grpc_cpp_generator {
 namespace {
 
+grpc::string message_header_ext() { return ".pb.h"; }
+grpc::string service_header_ext() { return ".grpc.pb.h"; }
+
 template <class T>
 grpc::string as_string(T x) {
   std::ostringstream out;
@@ -69,7 +72,7 @@ T *array_end(T (&array)[N]) {
   return array + N;
 }
 
-void PrintIncludes(Printer *printer, const std::vector<grpc::string> &headers,
+void PrintIncludes(grpc_generator::Printer *printer, const std::vector<grpc::string> &headers,
                    const Parameters &params) {
   std::map<grpc::string, grpc::string> vars;
 
@@ -90,7 +93,8 @@ void PrintIncludes(Printer *printer, const std::vector<grpc::string> &headers,
   }
 }
 
-grpc::string GetHeaderPrologue(File *file, const Parameters & /*params*/) {
+grpc::string GetHeaderPrologue(grpc_generator::File *file, 
+                                const Parameters & /*params*/) {
   grpc::string output;
   {
     // Scope the output stream so it closes and finalizes output to the string.
@@ -100,13 +104,13 @@ grpc::string GetHeaderPrologue(File *file, const Parameters & /*params*/) {
     vars["filename"] = file->filename();
     vars["filename_identifier"] = FilenameIdentifier(file->filename());
     vars["filename_base"] = file->filename_without_ext();
-    vars["message_header_ext"] = file->message_header_ext();
+    vars["message_header_ext"] = message_header_ext();
 
     printer->Print(vars, "// Generated by the gRPC C++ plugin.\n");
     printer->Print(vars,
                    "// If you make any local change, they will be lost.\n");
     printer->Print(vars, "// source: $filename$\n");
-    grpc::string leading_comments = file->GetLeadingComments();
+    grpc::string leading_comments = file->GetLeadingComments("//");
     if (!leading_comments.empty()) {
       printer->Print(vars, "// Original file comments:\n");
       printer->Print(leading_comments.c_str());
@@ -120,7 +124,8 @@ grpc::string GetHeaderPrologue(File *file, const Parameters & /*params*/) {
   return output;
 }
 
-grpc::string GetHeaderIncludes(File *file, const Parameters &params) {
+grpc::string GetHeaderIncludes(grpc_generator::File *file, 
+                                const Parameters &params) {
   grpc::string output;
   {
     // Scope the output stream so it closes and finalizes output to the string.
@@ -162,7 +167,7 @@ grpc::string GetHeaderIncludes(File *file, const Parameters &params) {
 }
 
 void PrintHeaderClientMethodInterfaces(
-    Printer *printer, const Method *method,
+    grpc_generator::Printer *printer, const grpc_generator::Method *method,
     std::map<grpc::string, grpc::string> *vars, bool is_public) {
   (*vars)["Method"] = method->name();
   (*vars)["Request"] = method->input_type_name();
@@ -187,7 +192,7 @@ void PrintHeaderClientMethodInterfaces(
                      "Async$Method$Raw(context, request, cq));\n");
       printer->Outdent();
       printer->Print("}\n");
-    } else if (method->ClientOnlyStreaming()) {
+    } else if (method->ClientStreaming()) {
       printer->Print(
           *vars,
           "std::unique_ptr< ::grpc::ClientWriterInterface< $Request$>>"
@@ -213,7 +218,7 @@ void PrintHeaderClientMethodInterfaces(
                      "Async$Method$Raw(context, response, cq, tag));\n");
       printer->Outdent();
       printer->Print("}\n");
-    } else if (method->ServerOnlyStreaming()) {
+    } else if (method->ServerStreaming()) {
       printer->Print(
           *vars,
           "std::unique_ptr< ::grpc::ClientReaderInterface< $Response$>>"
@@ -275,7 +280,7 @@ void PrintHeaderClientMethodInterfaces(
           "Async$Method$Raw(::grpc::ClientContext* context, "
           "const $Request$& request, "
           "::grpc::CompletionQueue* cq) = 0;\n");
-    } else if (method->ClientOnlyStreaming()) {
+    } else if (method->ClientStreaming()) {
       printer->Print(
           *vars,
           "virtual ::grpc::ClientWriterInterface< $Request$>*"
@@ -286,7 +291,7 @@ void PrintHeaderClientMethodInterfaces(
                      " Async$Method$Raw(::grpc::ClientContext* context, "
                      "$Response$* response, "
                      "::grpc::CompletionQueue* cq, void* tag) = 0;\n");
-    } else if (method->ServerOnlyStreaming()) {
+    } else if (method->ServerStreaming()) {
       printer->Print(
           *vars,
           "virtual ::grpc::ClientReaderInterface< $Response$>* $Method$Raw("
@@ -311,9 +316,10 @@ void PrintHeaderClientMethodInterfaces(
   }
 }
 
-void PrintHeaderClientMethod(Printer *printer, const Method *method,
-                             std::map<grpc::string, grpc::string> *vars,
-                             bool is_public) {
+void PrintHeaderClientMethod(grpc_generator::Printer *printer, 
+                            const grpc_generator::Method *method,
+                            std::map<grpc::string, grpc::string> *vars,
+                            bool is_public) {
   (*vars)["Method"] = method->name();
   (*vars)["Request"] = method->input_type_name();
   (*vars)["Response"] = method->output_type_name();
@@ -336,7 +342,7 @@ void PrintHeaderClientMethod(Printer *printer, const Method *method,
                      "Async$Method$Raw(context, request, cq));\n");
       printer->Outdent();
       printer->Print("}\n");
-    } else if (method->ClientOnlyStreaming()) {
+    } else if (method->ClientStreaming()) {
       printer->Print(
           *vars,
           "std::unique_ptr< ::grpc::ClientWriter< $Request$>>"
@@ -360,7 +366,7 @@ void PrintHeaderClientMethod(Printer *printer, const Method *method,
           "Async$Method$Raw(context, response, cq, tag));\n");
       printer->Outdent();
       printer->Print("}\n");
-    } else if (method->ServerOnlyStreaming()) {
+    } else if (method->ServerStreaming()) {
       printer->Print(
           *vars,
           "std::unique_ptr< ::grpc::ClientReader< $Response$>>"
@@ -418,7 +424,7 @@ void PrintHeaderClientMethod(Printer *printer, const Method *method,
                      "Async$Method$Raw(::grpc::ClientContext* context, "
                      "const $Request$& request, "
                      "::grpc::CompletionQueue* cq) override;\n");
-    } else if (method->ClientOnlyStreaming()) {
+    } else if (method->ClientStreaming()) {
       printer->Print(*vars,
                      "::grpc::ClientWriter< $Request$>* $Method$Raw("
                      "::grpc::ClientContext* context, $Response$* response) "
@@ -427,7 +433,7 @@ void PrintHeaderClientMethod(Printer *printer, const Method *method,
                      "::grpc::ClientAsyncWriter< $Request$>* Async$Method$Raw("
                      "::grpc::ClientContext* context, $Response$* response, "
                      "::grpc::CompletionQueue* cq, void* tag) override;\n");
-    } else if (method->ServerOnlyStreaming()) {
+    } else if (method->ServerStreaming()) {
       printer->Print(*vars,
                      "::grpc::ClientReader< $Response$>* $Method$Raw("
                      "::grpc::ClientContext* context, const $Request$& request)"
@@ -449,30 +455,32 @@ void PrintHeaderClientMethod(Printer *printer, const Method *method,
   }
 }
 
-void PrintHeaderClientMethodData(Printer *printer, const Method *method,
+void PrintHeaderClientMethodData(grpc_generator::Printer *printer, 
+                                const grpc_generator::Method *method,
                                  std::map<grpc::string, grpc::string> *vars) {
   (*vars)["Method"] = method->name();
   printer->Print(*vars, "const ::grpc::RpcMethod rpcmethod_$Method$_;\n");
 }
 
-void PrintHeaderServerMethodSync(Printer *printer, const Method *method,
+void PrintHeaderServerMethodSync(grpc_generator::Printer *printer, 
+                                  const grpc_generator::Method *method,
                                  std::map<grpc::string, grpc::string> *vars) {
   (*vars)["Method"] = method->name();
   (*vars)["Request"] = method->input_type_name();
   (*vars)["Response"] = method->output_type_name();
-  printer->Print(method->GetLeadingComments().c_str());
+  printer->Print(method->GetLeadingComments("//").c_str());
   if (method->NoStreaming()) {
     printer->Print(*vars,
                    "virtual ::grpc::Status $Method$("
                    "::grpc::ServerContext* context, const $Request$* request, "
                    "$Response$* response);\n");
-  } else if (method->ClientOnlyStreaming()) {
+  } else if (method->ClientStreaming()) {
     printer->Print(*vars,
                    "virtual ::grpc::Status $Method$("
                    "::grpc::ServerContext* context, "
                    "::grpc::ServerReader< $Request$>* reader, "
                    "$Response$* response);\n");
-  } else if (method->ServerOnlyStreaming()) {
+  } else if (method->ServerStreaming()) {
     printer->Print(*vars,
                    "virtual ::grpc::Status $Method$("
                    "::grpc::ServerContext* context, const $Request$* request, "
@@ -485,10 +493,11 @@ void PrintHeaderServerMethodSync(Printer *printer, const Method *method,
         "::grpc::ServerReaderWriter< $Response$, $Request$>* stream);"
         "\n");
   }
-  printer->Print(method->GetTrailingComments().c_str());
+  printer->Print(method->GetTrailingComments("//").c_str());
 }
 
-void PrintHeaderServerMethodAsync(Printer *printer, const Method *method,
+void PrintHeaderServerMethodAsync(grpc_generator::Printer *printer,
+                                 const grpc_generator::Method *method,
                                   std::map<grpc::string, grpc::string> *vars) {
   (*vars)["Method"] = method->name();
   (*vars)["Request"] = method->input_type_name();
@@ -530,7 +539,7 @@ void PrintHeaderServerMethodAsync(Printer *printer, const Method *method,
                    "  ::grpc::Service::RequestAsyncUnary($Idx$, context, "
                    "request, response, new_call_cq, notification_cq, tag);\n");
     printer->Print("}\n");
-  } else if (method->ClientOnlyStreaming()) {
+  } else if (method->ClientStreaming()) {
     printer->Print(
         *vars,
         "// disable synchronous version of this method\n"
@@ -552,7 +561,7 @@ void PrintHeaderServerMethodAsync(Printer *printer, const Method *method,
                    "  ::grpc::Service::RequestAsyncClientStreaming($Idx$, "
                    "context, reader, new_call_cq, notification_cq, tag);\n");
     printer->Print("}\n");
-  } else if (method->ServerOnlyStreaming()) {
+  } else if (method->ServerStreaming()) {
     printer->Print(
         *vars,
         "// disable synchronous version of this method\n"
@@ -603,7 +612,7 @@ void PrintHeaderServerMethodAsync(Printer *printer, const Method *method,
 }
 
 void PrintHeaderServerMethodStreamedUnary(
-    Printer *printer, const Method *method,
+    grpc_generator::Printer *printer, const grpc_generator::Method *method,
     std::map<grpc::string, grpc::string> *vars) {
   (*vars)["Method"] = method->name();
   (*vars)["Request"] = method->input_type_name();
@@ -654,12 +663,12 @@ void PrintHeaderServerMethodStreamedUnary(
 }
 
 void PrintHeaderServerMethodSplitStreaming(
-    Printer *printer, const Method *method,
+    grpc_generator::Printer *printer, const grpc_generator::Method *method,
     std::map<grpc::string, grpc::string> *vars) {
   (*vars)["Method"] = method->name();
   (*vars)["Request"] = method->input_type_name();
   (*vars)["Response"] = method->output_type_name();
-  if (method->ServerOnlyStreaming()) {
+  if (method->ServerStreaming()) {
     printer->Print(*vars, "template <class BaseClass>\n");
     printer->Print(*vars,
                    "class WithSplitStreamingMethod_$Method$ : "
@@ -706,7 +715,7 @@ void PrintHeaderServerMethodSplitStreaming(
 }
 
 void PrintHeaderServerMethodGeneric(
-    Printer *printer, const Method *method,
+    grpc_generator::Printer *printer, const grpc_generator::Method *method,
     std::map<grpc::string, grpc::string> *vars) {
   (*vars)["Method"] = method->name();
   (*vars)["Request"] = method->input_type_name();
@@ -737,7 +746,7 @@ void PrintHeaderServerMethodGeneric(
         "  abort();\n"
         "  return ::grpc::Status(::grpc::StatusCode::UNIMPLEMENTED, \"\");\n"
         "}\n");
-  } else if (method->ClientOnlyStreaming()) {
+  } else if (method->ClientStreaming()) {
     printer->Print(
         *vars,
         "// disable synchronous version of this method\n"
@@ -748,7 +757,7 @@ void PrintHeaderServerMethodGeneric(
         "  abort();\n"
         "  return ::grpc::Status(::grpc::StatusCode::UNIMPLEMENTED, \"\");\n"
         "}\n");
-  } else if (method->ServerOnlyStreaming()) {
+  } else if (method->ServerStreaming()) {
     printer->Print(
         *vars,
         "// disable synchronous version of this method\n"
@@ -775,11 +784,12 @@ void PrintHeaderServerMethodGeneric(
   printer->Print(*vars, "};\n");
 }
 
-void PrintHeaderService(Printer *printer, const Service *service,
+void PrintHeaderService(grpc_generator::Printer *printer, 
+                        const grpc_generator::Service *service,
                         std::map<grpc::string, grpc::string> *vars) {
   (*vars)["Service"] = service->name();
 
-  printer->Print(service->GetLeadingComments().c_str());
+  printer->Print(service->GetLeadingComments("//").c_str());
   printer->Print(*vars,
                  "class $Service$ final {\n"
                  " public:\n");
@@ -792,10 +802,10 @@ void PrintHeaderService(Printer *printer, const Service *service,
   printer->Indent();
   printer->Print("virtual ~StubInterface() {}\n");
   for (int i = 0; i < service->method_count(); ++i) {
-    printer->Print(service->method(i)->GetLeadingComments().c_str());
+    printer->Print(service->method(i)->GetLeadingComments("//").c_str());
     PrintHeaderClientMethodInterfaces(printer, service->method(i).get(), vars,
                                       true);
-    printer->Print(service->method(i)->GetTrailingComments().c_str());
+    printer->Print(service->method(i)->GetTrailingComments("//").c_str());
   }
   printer->Outdent();
   printer->Print("private:\n");
@@ -903,13 +913,13 @@ void PrintHeaderService(Printer *printer, const Service *service,
   printer->Print("typedef ");
   for (int i = 0; i < service->method_count(); ++i) {
     (*vars)["method_name"] = service->method(i).get()->name();
-    if (service->method(i)->ServerOnlyStreaming()) {
+    if (service->method(i)->ServerStreaming()) {
       printer->Print(*vars, "WithSplitStreamingMethod_$method_name$<");
     }
   }
   printer->Print("Service");
   for (int i = 0; i < service->method_count(); ++i) {
-    if (service->method(i)->ServerOnlyStreaming()) {
+    if (service->method(i)->ServerStreaming()) {
       printer->Print(" >");
     }
   }
@@ -919,7 +929,7 @@ void PrintHeaderService(Printer *printer, const Service *service,
   printer->Print("typedef ");
   for (int i = 0; i < service->method_count(); ++i) {
     (*vars)["method_name"] = service->method(i).get()->name();
-    if (service->method(i)->ServerOnlyStreaming()) {
+    if (service->method(i)->ServerStreaming()) {
       printer->Print(*vars, "WithSplitStreamingMethod_$method_name$<");
     }
     if (service->method(i)->NoStreaming()) {
@@ -929,7 +939,7 @@ void PrintHeaderService(Printer *printer, const Service *service,
   printer->Print("Service");
   for (int i = 0; i < service->method_count(); ++i) {
     if (service->method(i)->NoStreaming() ||
-        service->method(i)->ServerOnlyStreaming()) {
+        service->method(i)->ServerStreaming()) {
       printer->Print(" >");
     }
   }
@@ -937,10 +947,11 @@ void PrintHeaderService(Printer *printer, const Service *service,
 
   printer->Outdent();
   printer->Print("};\n");
-  printer->Print(service->GetTrailingComments().c_str());
+  printer->Print(service->GetTrailingComments("//").c_str());
 }
 
-grpc::string GetHeaderServices(File *file, const Parameters &params) {
+grpc::string GetHeaderServices(grpc_generator::File *file,
+                               const Parameters &params) {
   grpc::string output;
   {
     // Scope the output stream so it closes and finalizes output to the string.
@@ -970,7 +981,8 @@ grpc::string GetHeaderServices(File *file, const Parameters &params) {
   return output;
 }
 
-grpc::string GetHeaderEpilogue(File *file, const Parameters & /*params*/) {
+grpc::string GetHeaderEpilogue(grpc_generator::File *file,
+                               const Parameters & /*params*/) {
   grpc::string output;
   {
     // Scope the output stream so it closes and finalizes output to the string.
@@ -993,12 +1005,13 @@ grpc::string GetHeaderEpilogue(File *file, const Parameters & /*params*/) {
     printer->Print(vars, "\n");
     printer->Print(vars, "#endif  // GRPC_$filename_identifier$__INCLUDED\n");
 
-    printer->Print(file->GetTrailingComments().c_str());
+    printer->Print(file->GetTrailingComments("//").c_str());
   }
   return output;
 }
 
-grpc::string GetSourcePrologue(File *file, const Parameters & /*params*/) {
+grpc::string GetSourcePrologue(grpc_generator::File *file,
+                               const Parameters & /*params*/) {
   grpc::string output;
   {
     // Scope the output stream so it closes and finalizes output to the string.
@@ -1007,8 +1020,8 @@ grpc::string GetSourcePrologue(File *file, const Parameters & /*params*/) {
 
     vars["filename"] = file->filename();
     vars["filename_base"] = file->filename_without_ext();
-    vars["message_header_ext"] = file->message_header_ext();
-    vars["service_header_ext"] = file->service_header_ext();
+    vars["message_header_ext"] = message_header_ext();
+    vars["service_header_ext"] = service_header_ext();
 
     printer->Print(vars, "// Generated by the gRPC C++ plugin.\n");
     printer->Print(vars,
@@ -1023,7 +1036,8 @@ grpc::string GetSourcePrologue(File *file, const Parameters & /*params*/) {
   return output;
 }
 
-grpc::string GetSourceIncludes(File *file, const Parameters &params) {
+grpc::string GetSourceIncludes(grpc_generator::File *file,
+                               const Parameters &params) {
   grpc::string output;
   {
     // Scope the output stream so it closes and finalizes output to the string.
@@ -1056,7 +1070,8 @@ grpc::string GetSourceIncludes(File *file, const Parameters &params) {
   return output;
 }
 
-void PrintSourceClientMethod(Printer *printer, const Method *method,
+void PrintSourceClientMethod(grpc_generator::Printer *printer, 
+                            const grpc_generator::Method *method,
                              std::map<grpc::string, grpc::string> *vars) {
   (*vars)["Method"] = method->name();
   (*vars)["Request"] = method->input_type_name();
@@ -1084,7 +1099,7 @@ void PrintSourceClientMethod(Printer *printer, const Method *method,
                    "rpcmethod_$Method$_, "
                    "context, request);\n"
                    "}\n\n");
-  } else if (method->ClientOnlyStreaming()) {
+  } else if (method->ClientStreaming()) {
     printer->Print(*vars,
                    "::grpc::ClientWriter< $Request$>* "
                    "$ns$$Service$::Stub::$Method$Raw("
@@ -1106,7 +1121,7 @@ void PrintSourceClientMethod(Printer *printer, const Method *method,
                    "rpcmethod_$Method$_, "
                    "context, response, tag);\n"
                    "}\n\n");
-  } else if (method->ServerOnlyStreaming()) {
+  } else if (method->ServerStreaming()) {
     printer->Print(
         *vars,
         "::grpc::ClientReader< $Response$>* "
@@ -1156,7 +1171,8 @@ void PrintSourceClientMethod(Printer *printer, const Method *method,
   }
 }
 
-void PrintSourceServerMethod(Printer *printer, const Method *method,
+void PrintSourceServerMethod(grpc_generator::Printer *printer,
+                            const grpc_generator::Method *method,
                              std::map<grpc::string, grpc::string> *vars) {
   (*vars)["Method"] = method->name();
   (*vars)["Request"] = method->input_type_name();
@@ -1173,7 +1189,7 @@ void PrintSourceServerMethod(Printer *printer, const Method *method,
         "  return ::grpc::Status("
         "::grpc::StatusCode::UNIMPLEMENTED, \"\");\n");
     printer->Print("}\n\n");
-  } else if (method->ClientOnlyStreaming()) {
+  } else if (method->ClientStreaming()) {
     printer->Print(*vars,
                    "::grpc::Status $ns$$Service$::Service::$Method$("
                    "::grpc::ServerContext* context, "
@@ -1186,7 +1202,7 @@ void PrintSourceServerMethod(Printer *printer, const Method *method,
         "  return ::grpc::Status("
         "::grpc::StatusCode::UNIMPLEMENTED, \"\");\n");
     printer->Print("}\n\n");
-  } else if (method->ServerOnlyStreaming()) {
+  } else if (method->ServerStreaming()) {
     printer->Print(*vars,
                    "::grpc::Status $ns$$Service$::Service::$Method$("
                    "::grpc::ServerContext* context, "
@@ -1214,7 +1230,8 @@ void PrintSourceServerMethod(Printer *printer, const Method *method,
   }
 }
 
-void PrintSourceService(Printer *printer, const Service *service,
+void PrintSourceService(grpc_generator::Printer *printer, 
+                        const grpc_generator::Service *service,
                         std::map<grpc::string, grpc::string> *vars) {
   (*vars)["Service"] = service->name();
 
@@ -1250,9 +1267,9 @@ void PrintSourceService(Printer *printer, const Service *service,
       // NOTE: There is no reason to consider streamed-unary as a separate
       // category here since this part is setting up the client-side stub
       // and this appears as a NORMAL_RPC from the client-side.
-    } else if (method->ClientOnlyStreaming()) {
+    } else if (method->ClientStreaming()) {
       (*vars)["StreamingType"] = "CLIENT_STREAMING";
-    } else if (method->ServerOnlyStreaming()) {
+    } else if (method->ServerStreaming()) {
       (*vars)["StreamingType"] = "SERVER_STREAMING";
     } else {
       (*vars)["StreamingType"] = "BIDI_STREAMING";
@@ -1290,7 +1307,7 @@ void PrintSourceService(Printer *printer, const Service *service,
           "$Request$, "
           "$Response$>(\n"
           "        std::mem_fn(&$ns$$Service$::Service::$Method$), this)));\n");
-    } else if (method->ClientOnlyStreaming()) {
+    } else if (method->ClientStreaming()) {
       printer->Print(
           *vars,
           "AddMethod(new ::grpc::RpcServiceMethod(\n"
@@ -1299,7 +1316,7 @@ void PrintSourceService(Printer *printer, const Service *service,
           "    new ::grpc::ClientStreamingHandler< "
           "$ns$$Service$::Service, $Request$, $Response$>(\n"
           "        std::mem_fn(&$ns$$Service$::Service::$Method$), this)));\n");
-    } else if (method->ServerOnlyStreaming()) {
+    } else if (method->ServerStreaming()) {
       printer->Print(
           *vars,
           "AddMethod(new ::grpc::RpcServiceMethod(\n"
@@ -1330,7 +1347,8 @@ void PrintSourceService(Printer *printer, const Service *service,
   }
 }
 
-grpc::string GetSourceServices(File *file, const Parameters &params) {
+grpc::string GetSourceServices(grpc_generator::File *file,
+                               const Parameters &params) {
   grpc::string output;
   {
     // Scope the output stream so it closes and finalizes output to the string.
@@ -1358,7 +1376,8 @@ grpc::string GetSourceServices(File *file, const Parameters &params) {
   return output;
 }
 
-grpc::string GetSourceEpilogue(File *file, const Parameters & /*params*/) {
+grpc::string GetSourceEpilogue(grpc_generator::File *file,
+                               const Parameters & /*params*/) {
   grpc::string temp;
 
   if (!file->package().empty()) {
diff --git a/src/compiler/cpp_generator.h b/src/compiler/cpp_generator.h
index d0343e9978b..dde72025c8a 100644
--- a/src/compiler/cpp_generator.h
+++ b/src/compiler/cpp_generator.h
@@ -42,6 +42,7 @@
 #include <vector>
 
 #include "src/compiler/config.h"
+#include "src/compiler/schema_interface.h"
 
 #ifndef GRPC_CUSTOM_STRING
 #include <string>
@@ -66,91 +67,29 @@ struct Parameters {
   grpc::string grpc_search_path;
 };
 
-// A common interface for objects having comments in the source.
-// Return formatted comments to be inserted in generated code.
-struct CommentHolder {
-  virtual ~CommentHolder() {}
-  virtual grpc::string GetLeadingComments() const = 0;
-  virtual grpc::string GetTrailingComments() const = 0;
-};
-
-// An abstract interface representing a method.
-struct Method : public CommentHolder {
-  virtual ~Method() {}
-
-  virtual grpc::string name() const = 0;
-
-  virtual grpc::string input_type_name() const = 0;
-  virtual grpc::string output_type_name() const = 0;
-
-  virtual bool NoStreaming() const = 0;
-  virtual bool ClientOnlyStreaming() const = 0;
-  virtual bool ServerOnlyStreaming() const = 0;
-  virtual bool BidiStreaming() const = 0;
-};
-
-// An abstract interface representing a service.
-struct Service : public CommentHolder {
-  virtual ~Service() {}
-
-  virtual grpc::string name() const = 0;
-
-  virtual int method_count() const = 0;
-  virtual std::unique_ptr<const Method> method(int i) const = 0;
-};
-
-struct Printer {
-  virtual ~Printer() {}
-
-  virtual void Print(const std::map<grpc::string, grpc::string> &vars,
-                     const char *template_string) = 0;
-  virtual void Print(const char *string) = 0;
-  virtual void Indent() = 0;
-  virtual void Outdent() = 0;
-};
-
-// An interface that allows the source generated to be output using various
-// libraries/idls/serializers.
-struct File : public CommentHolder {
-  virtual ~File() {}
-
-  virtual grpc::string filename() const = 0;
-  virtual grpc::string filename_without_ext() const = 0;
-  virtual grpc::string message_header_ext() const = 0;
-  virtual grpc::string service_header_ext() const = 0;
-  virtual grpc::string package() const = 0;
-  virtual std::vector<grpc::string> package_parts() const = 0;
-  virtual grpc::string additional_headers() const = 0;
-
-  virtual int service_count() const = 0;
-  virtual std::unique_ptr<const Service> service(int i) const = 0;
-
-  virtual std::unique_ptr<Printer> CreatePrinter(grpc::string *str) const = 0;
-};
-
 // Return the prologue of the generated header file.
-grpc::string GetHeaderPrologue(File *file, const Parameters &params);
+grpc::string GetHeaderPrologue(grpc_generator::File *file, const Parameters &params);
 
 // Return the includes needed for generated header file.
-grpc::string GetHeaderIncludes(File *file, const Parameters &params);
+grpc::string GetHeaderIncludes(grpc_generator::File *file, const Parameters &params);
 
 // Return the includes needed for generated source file.
-grpc::string GetSourceIncludes(File *file, const Parameters &params);
+grpc::string GetSourceIncludes(grpc_generator::File *file, const Parameters &params);
 
 // Return the epilogue of the generated header file.
-grpc::string GetHeaderEpilogue(File *file, const Parameters &params);
+grpc::string GetHeaderEpilogue(grpc_generator::File *file, const Parameters &params);
 
 // Return the prologue of the generated source file.
-grpc::string GetSourcePrologue(File *file, const Parameters &params);
+grpc::string GetSourcePrologue(grpc_generator::File *file, const Parameters &params);
 
 // Return the services for generated header file.
-grpc::string GetHeaderServices(File *file, const Parameters &params);
+grpc::string GetHeaderServices(grpc_generator::File *file, const Parameters &params);
 
 // Return the services for generated source file.
-grpc::string GetSourceServices(File *file, const Parameters &params);
+grpc::string GetSourceServices(grpc_generator::File *file, const Parameters &params);
 
 // Return the epilogue of the generated source file.
-grpc::string GetSourceEpilogue(File *file, const Parameters &params);
+grpc::string GetSourceEpilogue(grpc_generator::File *file, const Parameters &params);
 
 }  // namespace grpc_cpp_generator
 
diff --git a/src/compiler/cpp_generator_helpers.h b/src/compiler/cpp_generator_helpers.h
index 87e278f1b9f..83932a09bb8 100644
--- a/src/compiler/cpp_generator_helpers.h
+++ b/src/compiler/cpp_generator_helpers.h
@@ -35,6 +35,7 @@
 #define GRPC_INTERNAL_COMPILER_CPP_GENERATOR_HELPERS_H
 
 #include <map>
+
 #include "src/compiler/config.h"
 #include "src/compiler/generator_helpers.h"
 
diff --git a/src/compiler/cpp_plugin.cc b/src/compiler/cpp_plugin.cc
index 38f8f738ed9..4ee05ee0370 100644
--- a/src/compiler/cpp_plugin.cc
+++ b/src/compiler/cpp_plugin.cc
@@ -40,139 +40,8 @@
 #include "src/compiler/config.h"
 
 #include "src/compiler/cpp_generator.h"
-#include "src/compiler/cpp_generator_helpers.h"
 #include "src/compiler/generator_helpers.h"
-
-using grpc_cpp_generator::GetCppComments;
-
-class ProtoBufMethod : public grpc_cpp_generator::Method {
- public:
-  ProtoBufMethod(const grpc::protobuf::MethodDescriptor *method)
-      : method_(method) {}
-
-  grpc::string name() const { return method_->name(); }
-
-  grpc::string input_type_name() const {
-    return grpc_cpp_generator::ClassName(method_->input_type(), true);
-  }
-  grpc::string output_type_name() const {
-    return grpc_cpp_generator::ClassName(method_->output_type(), true);
-  }
-
-  bool NoStreaming() const {
-    return !method_->client_streaming() && !method_->server_streaming();
-  }
-
-  bool ClientOnlyStreaming() const {
-    return method_->client_streaming() && !method_->server_streaming();
-  }
-
-  bool ServerOnlyStreaming() const {
-    return !method_->client_streaming() && method_->server_streaming();
-  }
-
-  bool BidiStreaming() const {
-    return method_->client_streaming() && method_->server_streaming();
-  }
-
-  grpc::string GetLeadingComments() const {
-    return GetCppComments(method_, true);
-  }
-
-  grpc::string GetTrailingComments() const {
-    return GetCppComments(method_, false);
-  }
-
- private:
-  const grpc::protobuf::MethodDescriptor *method_;
-};
-
-class ProtoBufService : public grpc_cpp_generator::Service {
- public:
-  ProtoBufService(const grpc::protobuf::ServiceDescriptor *service)
-      : service_(service) {}
-
-  grpc::string name() const { return service_->name(); }
-
-  int method_count() const { return service_->method_count(); };
-  std::unique_ptr<const grpc_cpp_generator::Method> method(int i) const {
-    return std::unique_ptr<const grpc_cpp_generator::Method>(
-        new ProtoBufMethod(service_->method(i)));
-  };
-
-  grpc::string GetLeadingComments() const {
-    return GetCppComments(service_, true);
-  }
-
-  grpc::string GetTrailingComments() const {
-    return GetCppComments(service_, false);
-  }
-
- private:
-  const grpc::protobuf::ServiceDescriptor *service_;
-};
-
-class ProtoBufPrinter : public grpc_cpp_generator::Printer {
- public:
-  ProtoBufPrinter(grpc::string *str)
-      : output_stream_(str), printer_(&output_stream_, '$') {}
-
-  void Print(const std::map<grpc::string, grpc::string> &vars,
-             const char *string_template) {
-    printer_.Print(vars, string_template);
-  }
-
-  void Print(const char *string) { printer_.Print(string); }
-  void Indent() { printer_.Indent(); }
-  void Outdent() { printer_.Outdent(); }
-
- private:
-  grpc::protobuf::io::StringOutputStream output_stream_;
-  grpc::protobuf::io::Printer printer_;
-};
-
-class ProtoBufFile : public grpc_cpp_generator::File {
- public:
-  ProtoBufFile(const grpc::protobuf::FileDescriptor *file) : file_(file) {}
-
-  grpc::string filename() const { return file_->name(); }
-  grpc::string filename_without_ext() const {
-    return grpc_generator::StripProto(filename());
-  }
-
-  grpc::string message_header_ext() const { return ".pb.h"; }
-  grpc::string service_header_ext() const { return ".grpc.pb.h"; }
-
-  grpc::string package() const { return file_->package(); }
-  std::vector<grpc::string> package_parts() const {
-    return grpc_generator::tokenize(package(), ".");
-  }
-
-  grpc::string additional_headers() const { return ""; }
-
-  int service_count() const { return file_->service_count(); };
-  std::unique_ptr<const grpc_cpp_generator::Service> service(int i) const {
-    return std::unique_ptr<const grpc_cpp_generator::Service>(
-        new ProtoBufService(file_->service(i)));
-  }
-
-  std::unique_ptr<grpc_cpp_generator::Printer> CreatePrinter(
-      grpc::string *str) const {
-    return std::unique_ptr<grpc_cpp_generator::Printer>(
-        new ProtoBufPrinter(str));
-  }
-
-  grpc::string GetLeadingComments() const {
-    return GetCppComments(file_, true);
-  }
-
-  grpc::string GetTrailingComments() const {
-    return GetCppComments(file_, false);
-  }
-
- private:
-  const grpc::protobuf::FileDescriptor *file_;
-};
+#include "src/compiler/protobuf_plugin.h"
 
 class CppGrpcGenerator : public grpc::protobuf::compiler::CodeGenerator {
  public:
diff --git a/src/compiler/protobuf_plugin.h b/src/compiler/protobuf_plugin.h
new file mode 100644
index 00000000000..23ba49c7a77
--- /dev/null
+++ b/src/compiler/protobuf_plugin.h
@@ -0,0 +1,146 @@
+
+#ifndef GRPC_INTERNAL_COMPILER_PROTOBUF_PLUGIN_H
+#define GRPC_INTERNAL_COMPILER_PROTOBUF_PLUGIN_H
+
+#include "src/compiler/config.h"
+#include "src/compiler/schema_interface.h"
+#include "src/compiler/cpp_generator_helpers.h"
+
+#include <vector>
+
+// Get leading or trailing comments in a string.
+template <typename DescriptorType>
+inline grpc::string GetCommentsHelper(const DescriptorType *desc, bool leading,       
+                                       const grpc::string &prefix) {
+  return grpc_generator::GetPrefixedComments(desc, leading, prefix);
+}
+
+class ProtoBufMethod : public grpc_generator::Method {
+  public:
+    ProtoBufMethod(const grpc::protobuf::MethodDescriptor *method)
+      : method_(method) {}
+
+    grpc::string name() const { return method_->name(); }
+
+    grpc::string input_type_name() const {
+      return grpc_cpp_generator::ClassName(method_->input_type(), true);
+    }
+    grpc::string output_type_name() const {
+      return grpc_cpp_generator::ClassName(method_->output_type(), true);
+    }
+
+    bool NoStreaming() const {
+      return !method_->client_streaming() && !method_->server_streaming();
+    }
+
+    bool ClientStreaming() const {
+   	  return method_->client_streaming() && !method_->server_streaming();
+    }
+
+    bool ServerStreaming() const {
+   	  return !method_->client_streaming() && method_->server_streaming();
+    }
+
+    bool BidiStreaming() const {
+      return method_->client_streaming() && method_->server_streaming();
+    } 
+
+    grpc::string GetLeadingComments(const grpc::string prefix) const {
+      return GetCommentsHelper(method_, true, prefix);
+    }
+
+    grpc::string GetTrailingComments(const grpc::string prefix) const {
+      return GetCommentsHelper(method_, false, prefix);
+    }
+
+  private:
+   const grpc::protobuf::MethodDescriptor *method_;
+ };
+
+class ProtoBufService : public grpc_generator::Service {
+  public:
+   ProtoBufService(const grpc::protobuf::ServiceDescriptor *service)
+       : service_(service) {}
+
+   grpc::string name() const { return service_->name(); }
+
+   int method_count() const { return service_->method_count(); };
+   std::unique_ptr<const grpc_generator::Method> method(int i) const {
+     return std::unique_ptr<const grpc_generator::Method>(
+         new ProtoBufMethod(service_->method(i)));
+   };
+
+   grpc::string GetLeadingComments(const grpc::string prefix) const {
+     return GetCommentsHelper(service_, true, prefix);
+   }
+
+   grpc::string GetTrailingComments(const grpc::string prefix) const {
+     return GetCommentsHelper(service_, false, prefix);
+   }
+
+  private:
+   const grpc::protobuf::ServiceDescriptor *service_;
+};
+
+class ProtoBufPrinter : public grpc_generator::Printer {
+  public:
+    ProtoBufPrinter(grpc::string *str)
+       : output_stream_(str), printer_(&output_stream_, '$') {}
+
+    void Print(const std::map<grpc::string, grpc::string> &vars,
+              const char *string_template) {
+      printer_.Print(vars, string_template);
+    }
+
+    void Print(const char *string) { printer_.Print(string); }
+    void Indent() { printer_.Indent(); }
+    void Outdent() { printer_.Outdent(); }
+
+  private:
+    grpc::protobuf::io::StringOutputStream output_stream_;
+    grpc::protobuf::io::Printer printer_;
+ };
+
+class ProtoBufFile : public grpc_generator::File {
+  public:
+   ProtoBufFile(const grpc::protobuf::FileDescriptor *file) : file_(file) {}
+
+   grpc::string filename() const { return file_->name(); }
+   grpc::string filename_without_ext() const {
+     return grpc_generator::StripProto(filename());
+   }
+
+   grpc::string package() const { return file_->package(); }
+   std::vector<grpc::string> package_parts() const {
+     return grpc_generator::tokenize(package(), ".");
+   }
+
+   grpc::string additional_headers() const { return ""; }
+
+   int service_count() const { return file_->service_count(); };
+   std::unique_ptr<const grpc_generator::Service> service(int i) const {
+     return std::unique_ptr<const grpc_generator::Service>(
+         new ProtoBufService(file_->service(i)));
+   }
+
+   std::unique_ptr<grpc_generator::Printer> CreatePrinter(
+       grpc::string *str) const {
+     return std::unique_ptr<grpc_generator::Printer>(
+         new ProtoBufPrinter(str));
+   }
+
+   grpc::string GetLeadingComments(const grpc::string prefix) const {
+     return GetCommentsHelper(file_, true, prefix);
+   }
+
+   grpc::string GetTrailingComments(const grpc::string prefix) const {
+     return GetCommentsHelper(file_, false, prefix);
+   }
+
+  private:
+   const grpc::protobuf::FileDescriptor *file_;
+};
+
+
+
+#endif  // GRPC_INTERNAL_COMPILER_PROTOBUF_PLUGIN_H
\ No newline at end of file
diff --git a/src/compiler/python_generator.h b/src/compiler/python_generator.h
index b91059fad77..0c0d7449b56 100644
--- a/src/compiler/python_generator.h
+++ b/src/compiler/python_generator.h
@@ -37,6 +37,7 @@
 #include <utility>
 
 #include "src/compiler/config.h"
+#include "src/compiler/schema_interface.h"
 
 namespace grpc_python_generator {
 
diff --git a/src/compiler/python_plugin.cc b/src/compiler/python_plugin.cc
index 3457aa631a3..f34abcc3139 100644
--- a/src/compiler/python_plugin.cc
+++ b/src/compiler/python_plugin.cc
@@ -34,6 +34,7 @@
 // Generates a Python gRPC service interface out of Protobuf IDL.
 
 #include "src/compiler/config.h"
+#include "src/compiler/protobuf_plugin.h"
 #include "src/compiler/python_generator.h"
 
 int main(int argc, char* argv[]) {
diff --git a/src/compiler/schema_interface.h b/src/compiler/schema_interface.h
new file mode 100644
index 00000000000..9c2ee5467e8
--- /dev/null
+++ b/src/compiler/schema_interface.h
@@ -0,0 +1,114 @@
+/*
+ *
+ * Copyright 2015, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#ifndef GRPC_INTERNAL_COMPILER_SCHEMA_INTERFACE_H
+#define GRPC_INTERNAL_COMPILER_SCHEMA_INTERFACE_H
+
+#include <memory>
+#include <vector>
+
+#ifndef GRPC_CUSTOM_STRING
+#include <string>
+#define GRPC_CUSTOM_STRING std::string
+#endif
+
+namespace grpc {
+
+  typedef GRPC_CUSTOM_STRING string;
+
+}  // namespace grpc
+
+namespace grpc_generator {
+
+  // A common interface for objects having comments in the source.
+  // Return formatted comments to be inserted in generated code.
+  struct CommentHolder {
+    virtual ~CommentHolder() {}
+    virtual grpc::string GetLeadingComments(const grpc::string prefix) const = 0;
+    virtual grpc::string GetTrailingComments(const grpc::string prefix) const = 0;
+  };
+
+  // An abstract interface representing a method.
+  struct Method : public CommentHolder {
+    virtual ~Method() {}
+
+    virtual grpc::string name() const = 0;
+
+    virtual grpc::string input_type_name() const = 0;
+    virtual grpc::string output_type_name() const = 0;
+
+    virtual bool NoStreaming() const = 0;
+    virtual bool ClientStreaming() const = 0;
+    virtual bool ServerStreaming() const = 0;
+    virtual bool BidiStreaming() const = 0;
+  };
+
+  // An abstract interface representing a service.
+  struct Service : public CommentHolder {
+    virtual ~Service() {}
+
+    virtual grpc::string name() const = 0;
+
+    virtual int method_count() const = 0;
+    virtual std::unique_ptr<const Method> method(int i) const = 0;
+  };
+
+  struct Printer {
+    virtual ~Printer() {}
+
+    virtual void Print(const std::map<grpc::string, grpc::string> &vars,
+                       const char *template_string) = 0;
+    virtual void Print(const char *string) = 0;
+    virtual void Indent() = 0;
+    virtual void Outdent() = 0;
+  };
+
+  // An interface that allows the source generated to be output using various
+  // libraries/idls/serializers.
+  struct File : public CommentHolder {
+    virtual ~File() {}
+
+    virtual grpc::string filename() const = 0;
+    virtual grpc::string filename_without_ext() const = 0;
+    virtual grpc::string package() const = 0;
+    virtual std::vector<grpc::string> package_parts() const = 0;
+    virtual grpc::string additional_headers() const = 0;
+
+    virtual int service_count() const = 0;
+    virtual std::unique_ptr<const Service> service(int i) const = 0;
+
+    virtual std::unique_ptr<Printer> CreatePrinter(grpc::string *str) const = 0;
+  };
+} // namespace grpc_generator
+
+#endif  // GRPC_INTERNAL_COMPILER_SCHEMA_INTERFACE_H