flatbuffers/docs/source/gRPC/CppUsage.md

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[C++] Improve flatbuffers + gRPC integration (#4310) * Rework flatbuffers + gRPC integration - Introduce `flatbuffers::grpc::Message<T>`, a `grpc_slice`-backed message buffer that handles refcounting and allows flatbuffers to transfer ownership to gRPC efficiently. This replaces `flatbuffers::BufferRef<T>`, which required a copy call and was also unsafe w.r.t. buffer lifetime. - Introduce `flatbuffers::grpc::MessageBuilder`, a gRPC-specific builder that forces a `grpc_slice`-backed allocator and also adds some helpful `Message<T>`-related methods. - Update serializers accordingly (now zero-copy between flatbuffers and gRPC). * gRPC: verify messages by default, but allow user to override * gRPC: fix some formatting issues * Disable verification by default, but add helper method * Make FlatBufferBuilder fields protected + remove vec accessor * Use bool add_ref parameter to toggle refcount incr * Remove unnecessary inline specifiers * Fix formatting * Use auto * Remove empty lines * Use grpc_slice helper macros * Simplify reset code * Disable Message copy ctor and assignment by default * Remove unused member * Enable gRPC verification by default * Use auto * Bake in message verification (remove template specialization) * Add RoundUp func * Consolidate gRPC message copy flag * Make vector_downward allocations fully lazy * Test message verification failure code/message * Add grpctest verification test comments * Simplify reallocate implementation * Make initial_size a size_t * Use ternary op for growth_policy * Use truthiness rather than dont explicit nullptr check * Indent preprocessor directives * Remove grpc message copy/assignment * Fix a few bugs * Add gRPC example * Add basic gRPC docs * Use doxygen EXAMPLE_PATH + @include * Reference example fbs in grpc docs * Move gRPC examples into grpc/samples * Fix pointer/reference formatting * Use std::function rather than templated callback func * Create fresh message builder for each request * Use Clear() in Reset() impl * Use FLATBUFFERS_CONSTEXPR
2017-06-07 20:56:49 +00:00
Use in C++ {#flatbuffers_grpc_guide_use_cpp}
==========
## Before you get started
Before diving into the FlatBuffers gRPC usage in C++, you should already be
familiar with the following:
- FlatBuffers as a serialization format
- [gRPC](http://www.grpc.io/docs/) usage
## Using the FlatBuffers gRPC C++ library
NOTE: The examples below are also in the `grpc/samples/greeter` directory.
We will illustrate usage with the following schema:
@include grpc/samples/greeter/greeter.fbs
When we run `flatc`, we pass in the `--grpc` option and generage an additional
`greeter.grpc.fb.h` and `greeter.grpc.fb.cc`.
Example server code looks like this:
@include grpc/samples/greeter/server.cpp
Example client code looks like this:
@include grpc/samples/greeter/client.cpp