Remove onCreateInitialMetadata and move to supplying initial metadata as (proxy-wasm#6)

part of the call to create the gRPC stream. Signed-off-by: John Plevyak <jplevyak@gmail.com>

Author: jplevyak

docs/wasm_filter.md

@@ -975,7 +975,7 @@ class CallHandler : public GrpcCallHandler<google::protobuf::Empty> {
  /* override onSuccess code */
  }
  /*
- more callbacks such as onFailure, onCreateInitialMetadata
+ more callbacks such as onFailure
  */
 };
 ```
@@ -1011,15 +1011,6 @@ Called when the async gRPC request fails. No further callbacks will be
 invoked. *status* is returned grpc status. *error\_message* is the gRPC
 status message or empty string if not present.
 
-#### onCreateInitialMetadata
-
-``` {.sourceCode .cpp}
-void onCreateInitialMetadata()
-```
-
-Called when populating the headers to send with initial metadata. TODO:
-how to add metadata?
-
 #### cancel
 
 ``` {.sourceCode .cpp}
@@ -1043,7 +1034,7 @@ class StreamHandler : public GrpcStreamHandler<google::protobuf::Struct, google:
  /* override onReceive code */
  }
  /*
- more callbacks such as onCreateInitialMetadat, onReceiveTrailingMetadata, onReceive, onRemoteClose
+ more callbacks such as onReceiveTrailingMetadata, onReceive, onRemoteClose
  */
 };
 ```
@@ -1090,15 +1081,6 @@ Close the stream locally and remotely (as needed). No further methods
 may be invoked on the handler object and no further callbacks will be
 invoked.
 
-#### onCreateInitialMetadata
-
-``` {.sourceCode .cpp}
-void onCreateInitialMetadata()
-```
-
-Called when populating the headers to send with initial metadata. TODO:
-how to add initial metadata?
-
 #### onReceiveInitialMetadata
 
 ``` {.sourceCode .cpp}

proxy_wasm_api.h

@@ -196,7 +196,6 @@ class GrpcCallHandlerBase {
 
  void cancel();
 
- virtual void onCreateInitialMetadata(uint32_t /* headers */) {}
  virtual void onSuccess(size_t body_size) = 0;
  virtual void onFailure(GrpcStatus status) = 0;
 
@@ -229,7 +228,6 @@ class GrpcStreamHandlerBase {
  // callbacks.
  void reset();
 
- virtual void onCreateInitialMetadata(uint32_t /* headers */) {}
  virtual void onReceiveInitialMetadata(uint32_t /* headers */) {}
  virtual void onReceiveTrailingMetadata(uint32_t /* trailers */) {}
  virtual void onReceive(size_t body_size) = 0;
@@ -324,7 +322,6 @@ class RootContext : public ContextBase {
  // Low level HTTP/gRPC interface.
  virtual void onHttpCallResponse(uint32_t token, uint32_t headers, size_t body_size,
  uint32_t trailers);
- virtual void onGrpcCreateInitialMetadata(uint32_t token, uint32_t headers);
  virtual void onGrpcReceiveInitialMetadata(uint32_t token, uint32_t headers);
  virtual void onGrpcReceiveTrailingMetadata(uint32_t token, uint32_t trailers);
  virtual void onGrpcReceive(uint32_t token, size_t body_size);
@@ -338,9 +335,11 @@ class RootContext : public ContextBase {
  // NB: the message is the response if status == OK and an error message
  // otherwise. Returns false on setup error.
  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);
  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,
@@ -352,16 +351,18 @@ class RootContext : public ContextBase {
  failure_callback(status);
  }
  };
- return grpcSimpleCall(service, service_name, method_name, request, timeout_milliseconds,
- callback);
+ return grpcSimpleCall(service, service_name, method_name, initial_metadata, request,
+ timeout_milliseconds, 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);
  // Returns false on setup error.
  WasmResult grpcStreamHandler(StringView service, StringView service_name, StringView method_name,
+ const HeaderStringPairs &initial_metadata,
  std::unique_ptr<GrpcStreamHandlerBase> handler);
 
 private:
@@ -1174,19 +1175,28 @@ inline Histogram<Tags...> *Histogram<Tags...>::New(StringView name,
 }
 
 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) {
+ 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(), serialized_request.data(),
- serialized_request.size(), timeout_milliseconds, token_ptr);
+ method_name.data(), method_name.size(), metadata_ptr, metadata_size,
+ serialized_request.data(), serialized_request.size(), timeout_milliseconds,
+ token_ptr);
 }
 
 inline WasmResult grpcStream(StringView service, StringView service_name, StringView method_name,
- uint32_t *token_ptr) {
+ const HeaderStringPairs &initial_metadata, uint32_t *token_ptr) {
+ void *metadata_ptr = nullptr;
+ size_t metadata_size = 0;
+ MakeHeaderStringPairsBuffer(initial_metadata, &metadata_ptr, &metadata_size);
  return proxy_grpc_stream(service.data(), service.size(), service_name.data(), service_name.size(),
- method_name.data(), method_name.size(), token_ptr);
+ method_name.data(), method_name.size(), metadata_ptr, metadata_size,
+ token_ptr);
 }
 
 inline WasmResult grpcCancel(uint32_t token) { return proxy_grpc_cancel(token); }
@@ -1221,12 +1231,13 @@ inline void RootContext::onHttpCallResponse(uint32_t token, uint32_t headers, si
 
 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,
  Context::GrpcSimpleCallCallback callback) {
  uint32_t token = 0;
- WasmResult result =
- grpcCall(service, service_name, method_name, request, timeout_milliseconds, &token);
+ WasmResult result = grpcCall(service, service_name, method_name, initial_metadata, request,
+   timeout_milliseconds, &token);
  if (result == WasmResult::Ok) {
  asRoot()->simple_grpc_calls_[token] = std::move(callback);
  }
@@ -1263,23 +1274,6 @@ inline void GrpcStreamHandlerBase::send(StringView message, bool end_of_stream)
  }
 }
 
-inline void RootContext::onGrpcCreateInitialMetadata(uint32_t token, uint32_t headers) {
- {
- auto it = grpc_calls_.find(token);
- if (it != grpc_calls_.end()) {
- it->second->onCreateInitialMetadata(headers);
- return;
- }
- }
- {
- auto it = grpc_streams_.find(token);
- if (it != grpc_streams_.end()) {
- it->second->onCreateInitialMetadata(headers);
- return;
- }
- }
-}
-
 inline void RootContext::onGrpcReceiveInitialMetadata(uint32_t token, uint32_t headers) {
  {
  auto it = grpc_streams_.find(token);
@@ -1370,11 +1364,13 @@ inline void RootContext::onGrpcClose(uint32_t token, GrpcStatus status) {
 
 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,
  std::unique_ptr<GrpcCallHandlerBase> handler) {
  uint32_t token = 0;
- auto result = grpcCall(service, service_name, method_name, request, timeout_milliseconds, &token);
+ auto result = grpcCall(service, service_name, method_name, initial_metadata, request,
+ timeout_milliseconds, &token);
  if (result == WasmResult::Ok) {
  handler->token_ = token;
  handler->context_ = this;
@@ -1385,9 +1381,10 @@ inline WasmResult RootContext::grpcCallHandler(StringView service, StringView se
 
 inline WasmResult RootContext::grpcStreamHandler(StringView service, StringView service_name,
  StringView method_name,
+ const HeaderStringPairs &initial_metadata,
  std::unique_ptr<GrpcStreamHandlerBase> handler) {
  uint32_t token = 0;
- auto result = grpcStream(service, service_name, method_name, &token);
+ auto result = grpcStream(service, service_name, method_name, initial_metadata, &token);
  if (result == WasmResult::Ok) {
  handler->token_ = token;
  handler->context_ = this;

proxy_wasm_externs.h

@@ -123,11 +123,13 @@ extern "C" WasmResult proxy_http_call(const char *uri_ptr, size_t uri_size, void
 extern "C" WasmResult proxy_grpc_call(const char *service_ptr, size_t service_size,
  const char *service_name_ptr, size_t service_name_size,
  const char *method_name_ptr, size_t method_name_size,
+ size_t initial_metadata_pairs_size, const char *request_ptr,
  const char *request_ptr, size_t request_size,
  uint32_t timeout_milliseconds, uint32_t *token_ptr);
 extern "C" WasmResult proxy_grpc_stream(const char *service_ptr, size_t service_size,
  const char *service_name_ptr, size_t service_name_size,
  const char *method_name_ptr, size_t method_name_size,
+ size_t initial_metadata_pairs_size, const char *request_ptr,
  uint32_t *token_ptr);
 extern "C" WasmResult proxy_grpc_cancel(uint32_t token);
 extern "C" WasmResult proxy_grpc_close(uint32_t token);

proxy_wasm_intrinsics.cc

@@ -243,11 +243,6 @@ extern "C" PROXY_WASM_KEEPALIVE void proxy_on_http_call_response(uint32_t contex
  ->onHttpCallResponse(token, headers, static_cast<size_t>(body_size), trailers);
 }
 
-extern "C" PROXY_WASM_KEEPALIVE void
-proxy_on_grpc_create_initial_metadata(uint32_t context_id, uint32_t token, uint32_t headers) {
- getRootContext(context_id)->onGrpcCreateInitialMetadata(token, headers);
-}
-
 extern "C" PROXY_WASM_KEEPALIVE void
 proxy_on_grpc_receive_initial_metadata(uint32_t context_id, uint32_t token, uint32_t headers) {
  getRootContext(context_id)->onGrpcReceiveInitialMetadata(token, headers);