support data injection

include/proxy-wasm/context.h

@@ -353,6 +353,12 @@ class ContextBase : public RootInterface,
                                std::string_view /* details */) override {
     return unimplemented();
   }
+
+  // Inject Data
+  WasmResult injectEncodedDataToFilterChain(std::string_view /* body_text */, bool /* end_stream */) override {
+    return unimplemented();
+  }
+
   void clearRouteCache() override { unimplemented(); }
   void failStream(WasmStreamType stream_type) override { closeStream(stream_type); }
 

include/proxy-wasm/context_interface.h

@@ -255,6 +255,9 @@ struct HttpInterface {
 
   // Call just before the Context is deleted. See RootInterface.
   virtual void onDelete() = 0;
+
+  // Inject encoded data to filter chain
+  virtual WasmResult injectEncodedDataToFilterChain(std::string_view /* body_text */, bool /* end_stream */) = 0;
 };
 
 /**

include/proxy-wasm/exports.h

@@ -78,6 +78,7 @@ Word send_local_response(Word response_code, Word response_code_details_ptr,
                          Word response_code_details_size, Word body_ptr, Word body_size,
                          Word additional_response_header_pairs_ptr,
                          Word additional_response_header_pairs_size, Word grpc_status);
+Word inject_encoded_data_to_filter_chain(Word body_ptr, Word body_size, Word end_stream);
 Word clear_route_cache();
 Word get_shared_data(Word key_ptr, Word key_size, Word value_ptr_ptr, Word value_size_ptr,
                      Word cas_ptr);
@@ -173,7 +174,7 @@ Word wasi_unstable_path_filestat_get(Word fd, Word flags, Word path, Word path_l
                                       _f(increment_metric) _f(record_metric) _f(get_metric)        \
                                           _f(set_effective_context) _f(done)                       \
                                               _f(call_foreign_function) _f(redis_init)             \
-                                                  _f(redis_call)
+                                                  _f(redis_call) _f(inject_encoded_data_to_filter_chain)
 
 #define FOR_ALL_HOST_FUNCTIONS_ABI_SPECIFIC(_f)                                                    \
   _f(get_configuration) _f(continue_request) _f(continue_response) _f(clear_route_cache)           \

include/proxy-wasm/wasm_api_impl.h

@@ -102,6 +102,11 @@ proxy_send_local_response(uint32_t response_code, const char *response_code_deta
       WR(body_ptr), WS(body_size), WR(additional_response_header_pairs_ptr),
       WS(additional_response_header_pairs_size), WS(grpc_status)));
 }
+inline WasmResult
+proxy_inject_encoded_data_to_filter_chain(const char *body_ptr, size_t body_size, bool end_stream) {
+  return wordToWasmResult(exports::inject_encoded_data_to_filter_chain(
+      WR(body_ptr), WS(body_size), WS(end_stream)));
+}
 
 inline WasmResult proxy_clear_route_cache() {
   return wordToWasmResult(exports::clear_route_cache());

src/exports.cc

@@ -159,6 +159,16 @@ Word send_local_response(Word response_code, Word response_code_details_ptr,
   return WasmResult::Ok;
 }
 
+Word inject_encoded_data_to_filter_chain(Word body_ptr, Word body_size, Word end_stream) {
+  auto *context = contextOrEffectiveContext();
+  auto body = context->wasmVm()->getMemory(body_ptr, body_size);
+  if (!body) {
+    return WasmResult::InvalidMemoryAccess;
+  }
+  context->injectEncodedDataToFilterChain(body.value(), end_stream != 0U);
+  return WasmResult::Ok;
+}
+
 Word clear_route_cache() {
   auto *context = contextOrEffectiveContext();
   context->clearRouteCache();

src/wasm.cc

@@ -153,6 +153,7 @@ void WasmBase::registerCallbacks() {
     _REGISTER_PROXY(get_log_level);
     _REGISTER_PROXY(redis_init);
     _REGISTER_PROXY(redis_call);
+    _REGISTER_PROXY(inject_encoded_data_to_filter_chain);
   }
 #undef _REGISTER_PROXY