Support raw/non-protobuf gRPC. (proxy-wasm#20)

Signed-off-by: John Plevyak <[email protected]>

Author: jplevyak

proxy_wasm_api.h

@@ -224,7 +224,7 @@ class GrpcStreamHandlerBase {
 
   // NB: with end_of_stream == true, callbacks can still occur: reset() to
   // prevent further callbacks.
-  void send(StringView message, bool end_of_stream);
+  WasmResult send(StringView message, bool end_of_stream);
   void close(); // NB: callbacks can still occur: reset() to prevent further
                 // callbacks.
   void reset();
@@ -251,13 +251,14 @@ class GrpcStreamHandler : public GrpcStreamHandlerBase {
   GrpcStreamHandler() : GrpcStreamHandlerBase() {}
   virtual ~GrpcStreamHandler() {}
 
-  void send(const Request &message, bool end_of_stream) {
+  WasmResult send(const Request &message, bool end_of_stream) {
     std::string output;
     if (!message.SerializeToString(&output)) {
-      return;
+      return WasmResult::SerializationFailure;
     }
     GrpcStreamHandlerBase::send(output, end_of_stream);
     local_close_ = local_close_ || end_of_stream;
+    return WasmResult::Ok;
   }
 
   virtual void onReceive(size_t body_size) = 0;
@@ -335,14 +336,11 @@ class RootContext : public ContextBase {
                       uint32_t timeout_milliseconds, HttpCallCallback callback);
   // NB: the message is the response if status == OK and an error message
   // otherwise. Returns false on setup error.
-#ifdef PROXY_WASM_PROTOBUF
   WasmResult grpcSimpleCall(StringView service, StringView service_name, StringView method_name,
-                            const HeaderStringPairs &initial_metadata,
-                            const google::protobuf::MessageLite &request,
+                            const HeaderStringPairs &initial_metadata, StringView request,
                             uint32_t timeout_milliseconds, GrpcSimpleCallCallback callback);
   WasmResult grpcSimpleCall(StringView service, StringView service_name, StringView method_name,
-                            const HeaderStringPairs &initial_metadata,
-                            const google::protobuf::MessageLite &request,
+                            const HeaderStringPairs &initial_metadata, StringView request,
                             uint32_t timeout_milliseconds,
                             std::function<void(size_t body_size)> success_callback,
                             std::function<void(GrpcStatus status)> failure_callback) {
@@ -356,12 +354,48 @@ class RootContext : public ContextBase {
     return grpcSimpleCall(service, service_name, method_name, initial_metadata, request,
                           timeout_milliseconds, callback);
   }
+  WasmResult grpcCallHandler(StringView service, StringView service_name, StringView method_name,
+                             const HeaderStringPairs &initial_metadata, StringView request,
+                             uint32_t timeout_milliseconds,
+                             std::unique_ptr<GrpcCallHandlerBase> handler);
+#ifdef PROXY_WASM_PROTOBUF
+  WasmResult grpcSimpleCall(StringView service, StringView service_name, StringView method_name,
+                            const HeaderStringPairs &initial_metadata,
+                            const google::protobuf::MessageLite &request,
+                            uint32_t timeout_milliseconds, GrpcSimpleCallCallback callback) {
+    std::string serialized_request;
+    if (!request.SerializeToString(&serialized_request)) {
+      return WasmResult::SerializationFailure;
+    }
+    return grpcSimpleCall(service, service_name, method_name, initial_metadata, serialized_request,
+                          timeout_milliseconds, callback);
+  }
+  WasmResult grpcSimpleCall(StringView service, StringView service_name, StringView method_name,
+                            const HeaderStringPairs &initial_metadata,
+                            const google::protobuf::MessageLite &request,
+                            uint32_t timeout_milliseconds,
+                            std::function<void(size_t body_size)> success_callback,
+                            std::function<void(GrpcStatus status)> failure_callback) {
+    std::string serialized_request;
+    if (!request.SerializeToString(&serialized_request)) {
+      return WasmResult::SerializationFailure;
+    }
+    return grpcSimpleCall(service, service_name, method_name, initial_metadata, serialized_request,
+                          timeout_milliseconds, success_callback, failure_callback);
+  }
   // Returns false on setup error.
   WasmResult grpcCallHandler(StringView service, StringView service_name, StringView method_name,
                              const HeaderStringPairs &initial_metadata,
                              const google::protobuf::MessageLite &request,
                              uint32_t timeout_milliseconds,
-                             std::unique_ptr<GrpcCallHandlerBase> handler);
+                             std::unique_ptr<GrpcCallHandlerBase> handler) {
+    std::string serialized_request;
+    if (!request.SerializeToString(&serialized_request)) {
+      return WasmResult::SerializationFailure;
+    }
+    return grpcCallHandler(service, service_name, method_name, initial_metadata, serialized_request,
+                           timeout_milliseconds, std::move(handler));
+  }
 #endif
   // Returns false on setup error.
   WasmResult grpcStreamHandler(StringView service, StringView service_name, StringView method_name,
@@ -1185,20 +1219,28 @@ inline Histogram<Tags...> *Histogram<Tags...>::New(StringView name,
                                 std::vector<MetricTag>({toMetricTag(descriptors)...}));
 }
 
-#ifdef PROXY_WASM_PROTOBUF
 inline WasmResult grpcCall(StringView service, StringView service_name, StringView method_name,
-                           const HeaderStringPairs &initial_metadata,
-                           const google::protobuf::MessageLite &request,
+                           const HeaderStringPairs &initial_metadata, StringView request,
                            uint32_t timeout_milliseconds, uint32_t *token_ptr) {
   void *metadata_ptr = nullptr;
   size_t metadata_size = 0;
   MakeHeaderStringPairsBuffer(initial_metadata, &metadata_ptr, &metadata_size);
-  std::string serialized_request;
-  request.SerializeToString(&serialized_request);
   return proxy_grpc_call(service.data(), service.size(), service_name.data(), service_name.size(),
                          method_name.data(), method_name.size(), metadata_ptr, metadata_size,
-                         serialized_request.data(), serialized_request.size(), timeout_milliseconds,
-                         token_ptr);
+                         request.data(), request.size(), timeout_milliseconds, token_ptr);
+}
+
+#ifdef PROXY_WASM_PROTOBUF
+inline WasmResult grpcCall(StringView service, StringView service_name, StringView method_name,
+                           const HeaderStringPairs &initial_metadata,
+                           const google::protobuf::MessageLite &request,
+                           uint32_t timeout_milliseconds, uint32_t *token_ptr) {
+  std::string serialized_request;
+  if (!request.SerializeToString(&serialized_request)) {
+    return WasmResult::SerializationFailure;
+  }
+  return grpcCall(service, service_name, method_name, initial_metadata, serialized_request,
+                  timeout_milliseconds, token_ptr);
 }
 #endif
 
@@ -1242,12 +1284,10 @@ inline void RootContext::onHttpCallResponse(uint32_t token, uint32_t headers, si
   }
 }
 
-#ifdef PROXY_WASM_PROTOBUF
 inline WasmResult RootContext::grpcSimpleCall(StringView service, StringView service_name,
                                               StringView method_name,
                                               const HeaderStringPairs &initial_metadata,
-                                              const google::protobuf::MessageLite &request,
-                                              uint32_t timeout_milliseconds,
+                                              StringView request, uint32_t timeout_milliseconds,
                                               Context::GrpcSimpleCallCallback callback) {
   uint32_t token = 0;
   WasmResult result = grpcCall(service, service_name, method_name, initial_metadata, request,
@@ -1257,7 +1297,6 @@ inline WasmResult RootContext::grpcSimpleCall(StringView service, StringView ser
   }
   return result;
 }
-#endif
 
 inline void GrpcCallHandlerBase::cancel() {
   grpcCancel(token_);
@@ -1278,15 +1317,19 @@ inline void GrpcStreamHandlerBase::close() {
   // NB: else callbacks can still occur: reset() to prevent further callbacks.
 }
 
-inline void GrpcStreamHandlerBase::send(StringView message, bool end_of_stream) {
-  grpcSend(token_, message, end_of_stream);
+inline WasmResult GrpcStreamHandlerBase::send(StringView message, bool end_of_stream) {
+  WasmResult r = grpcSend(token_, message, end_of_stream);
+  if (r != WasmResult::Ok) {
+    return r;
+  }
   if (end_of_stream) {
     // NB: callbacks can still occur: reset() to prevent further callbacks.
     local_close_ = local_close_ || end_of_stream;
     if (local_close_ && remote_close_) {
       context_->grpc_streams_.erase(token_);
     }
   }
+  return WasmResult::Ok;
 }
 
 inline void RootContext::onGrpcReceiveInitialMetadata(uint32_t token, uint32_t headers) {
@@ -1377,12 +1420,10 @@ inline void RootContext::onGrpcClose(uint32_t token, GrpcStatus status) {
   }
 }
 
-#ifdef PROXY_WASM_PROTOBUF
 inline WasmResult RootContext::grpcCallHandler(StringView service, StringView service_name,
                                                StringView method_name,
                                                const HeaderStringPairs &initial_metadata,
-                                               const google::protobuf::MessageLite &request,
-                                               uint32_t timeout_milliseconds,
+                                               StringView request, uint32_t timeout_milliseconds,
                                                std::unique_ptr<GrpcCallHandlerBase> handler) {
   uint32_t token = 0;
   auto result = grpcCall(service, service_name, method_name, initial_metadata, request,
@@ -1394,7 +1435,6 @@ inline WasmResult RootContext::grpcCallHandler(StringView service, StringView se
   }
   return result;
 }
-#endif
 
 inline WasmResult RootContext::grpcStreamHandler(StringView service, StringView service_name,
                                                  StringView method_name,