westonpace commented on code in PR #12672: URL: https://github.com/apache/arrow/pull/12672#discussion_r860414733
########## cpp/src/arrow/engine/substrait/util.cc: ########## @@ -0,0 +1,146 @@ +// Licensed to the Apache Software Foundation (ASF) under one +// or more contributor license agreements. See the NOTICE file +// distributed with this work for additional information +// regarding copyright ownership. The ASF licenses this file +// to you under the Apache License, Version 2.0 (the +// "License"); you may not use this file except in compliance +// with the License. You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, +// software distributed under the License is distributed on an +// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +// KIND, either express or implied. See the License for the +// specific language governing permissions and limitations +// under the License. + +#include "arrow/engine/substrait/util.h" +#include "arrow/util/async_generator.h" +#include "arrow/util/async_util.h" + +namespace arrow { + +namespace engine { + +/// \brief A SinkNodeConsumer specialized to output ExecBatches via PushGenerator +class ARROW_ENGINE_EXPORT SubstraitSinkConsumer : public compute::SinkNodeConsumer { + public: + explicit SubstraitSinkConsumer( + AsyncGenerator<util::optional<compute::ExecBatch>>* generator) + : producer_(MakeProducer(generator)) {} + + Status Consume(compute::ExecBatch batch) override { + // Consume a batch of data + bool did_push = producer_.Push(batch); + if (!did_push) return Status::ExecutionError("Producer closed already"); + return Status::OK(); + } + + Status Init(const std::shared_ptr<Schema>& schema, + compute::BackpressureControl* backpressure_control) override { + return Status::OK(); + } + + static arrow::PushGenerator<util::optional<compute::ExecBatch>>::Producer MakeProducer( + AsyncGenerator<util::optional<compute::ExecBatch>>* out_gen); + + Future<> Finish() override { + producer_.Push(IterationEnd<util::optional<compute::ExecBatch>>()); + if (producer_.Close()) { + return Future<>::MakeFinished(); + } + return Future<>::MakeFinished( + Status::ExecutionError("Error occurred in closing the batch producer")); Review Comment: Also, in C++11 the idea behind `ARROW_UNUSED` was officially added to the language so you might also see: ``` // Same as ARROW_UNUSED, this tells the compiler we know an error might be returned but we don't care std::ignore = thread_pool->Spawn(...); ``` In C++17 the `warn_unused_result` was officially added to the language so someday you might see: ``` // Only legal in C++17 but doesn't require a macro because all compilers should either // respect it or ignore it. class [[nodiscard]] Result ``` -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
