Your first C service¶

Build the library and call its calculator service from a native C client. The examples use the same Arrow schemas and dispatch code over subprocess and HTTP connections. Python is not needed for this build.

Install dependencies¶

You need a C11 compiler, CMake 3.20+, and the native libraries below.

macOSDebian / Ubuntu

brew install cmake pkg-config json-c libsodium libevent curl zstd lz4

sudo apt-get install build-essential cmake pkg-config libjson-c-dev \
  libsodium-dev libevent-dev libcurl4-openssl-dev libzstd-dev liblz4-dev zlib1g-dev

Build¶

git clone https://github.com/Query-farm/vgi-rpc-c.git
cd vgi-rpc-c
cmake -S . -B build -DCMAKE_BUILD_TYPE=Release
cmake --build build --parallel
ctest --test-dir build --output-on-failure

CMake fetches the pinned nanoarrow fork and applies the metadata patch. See building for dependency revisions, shared libraries, and local nanoarrow checkouts.

Call a subprocess¶

./build/vgi-rpc-example-client ./build/vgi-rpc-calculator

The client starts the worker, calls Calculator.add with two float64 arguments, and prints:

2 + 3 = 5

The client owns the subprocess and releases it when the call finishes.

Call over HTTP¶

Start the same server in one terminal:

./build/vgi-rpc-calculator --http 8000

Then call it from another terminal:

./build/vgi-rpc-example-client --http http://127.0.0.1:8000/vgi

The result is again 2 + 3 = 5. Stop the server with Ctrl-C when finished. The calculator walkthrough contains both complete C programs, included directly from the source files that CMake compiles.

Link your application¶

Install into a prefix your application can find:

cmake --install build --prefix "$HOME/.local"

Add the exported target to your application's CMakeLists.txt:

find_package(vgi_rpc 0.1 CONFIG REQUIRED)
add_executable(my_client main.c)
target_link_libraries(my_client PRIVATE vgi_rpc::vgi_rpc)

Configure your application with -DCMAKE_PREFIX_PATH="$HOME/.local" if that prefix is not already on CMake's search path. The target supplies nanoarrow's headers and libraries.

Continue with server handlers and ownership, the native client guide, or the public API reference.