Add cpp language support

Signed-off-by: Simone Orru <simone.orru@secomind.com>

.github/workflows/check-code-generation.yaml

@@ -39,3 +39,6 @@ jobs:
       - name: Check the Python generated code
         run: |
           git --no-pager diff --no-index -- ./python-dist ./python/astarteplatform
+      - name: Check the C++ generated code
+        run: |
+          git --no-pager diff --no-index -- ./cpp-dist ./cpp/astarteplatform

.github/workflows/code-generation.yaml

@@ -39,8 +39,11 @@ jobs:
   rust-code-generation:
     needs: [ reuse ]
     uses: ./.github/workflows/rust-code-generation.yaml
+  cpp-code-generation:
+    needs: [ reuse ]
+    uses: ./.github/workflows/cpp-code-generation.yaml
   check-codegen:
-    needs: [ python-code-generation, rust-code-generation ]
+    needs: [ python-code-generation, rust-code-generation, cpp-code-generation ]
     uses: ./.github/workflows/check-code-generation.yaml
   rust-code-check:
     needs: [ check-codegen ]

.github/workflows/cpp-code-generation.yaml

@@ -0,0 +1,67 @@
+# This file is part of Astarte.
+#
+# Copyright 2023 SECO Mind Srl
+#
+# Licensed 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.
+#
+# SPDX-License-Identifier: Apache-2.0
+
+name: C++ code generation
+
+permissions:
+  contents: read
+
+on:
+  workflow_call:
+
+env:
+  PB_REL: https://github.com/protocolbuffers/protobuf/releases
+  PB_VER: '26.1'
+
+jobs:
+  python-build:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v4
+    - name: Install protoc
+      run: |
+        curl -LO $PB_REL/download/v$PB_VER/protoc-$PB_VER-linux-x86_64.zip
+        unzip protoc-$PB_VER-linux-x86_64.zip -d $HOME/.local
+        echo "$HOME/.local/bin" >> $GITHUB_PATH
+    - name: Install gRPC
+      run: |
+        export MY_INSTALL_DIR=$HOME/.local
+        sudo apt install -y build-essential autoconf libtool pkg-config
+        git clone --recurse-submodules --depth 1 --shallow-submodules -b v1.66.1 https://github.com/grpc/grpc
+        mkdir -p cmake/build
+        pushd cmake/build
+        cmake -DgRPC_INSTALL=ON -DgRPC_BUILD_TESTS=OFF -DCMAKE_INSTALL_PREFIX=$MY_INSTALL_DIR ../..
+        make -j 4
+        make install
+        popd
+    - name: Remove old code
+      working-directory: ./cpp
+      run: (! test -d ./astarteplatform) || rm -r ./astarteplatform
+    - name: Generate code
+      working-directory: ./cpp
+      run: |
+        mkdir -p ./cmake/build
+        pushd ./cmake/build
+        cmake ../..
+        make
+        popd
+    - name: Upload artifact with generated code
+      uses: actions/upload-artifact@v4
+      with:
+        name: cpp-dist
+        path: ./cpp/astarteplatform

.gitignore

@@ -22,3 +22,6 @@ target/
 output/
 
 .pre-commit-config.yaml
+
+# CMake build directory
+cmake/

Makefile

@@ -29,6 +29,7 @@ CANONICAL_CURDIR = $(realpath $(CURDIR))
 PROTO_DIR = $(CANONICAL_CURDIR)/proto
 RUST_LANG_DIR = $(CANONICAL_CURDIR)/rust
 PYTHON_LANG_DIR = $(CANONICAL_CURDIR)/python
+CPP_LANG_DIR = $(CANONICAL_CURDIR)/cpp
 
 BASE_DIR := $(CANONICAL_O)
 $(if $(BASE_DIR),, $(error output directory "$(O)" does not exist))
@@ -39,6 +40,7 @@ DL_DIR := $(shell mkdir -p $(BASE_DIR)/dl >/dev/null 2>&1)$(BASE_DIR)/dl
 BUILD_DIR := $(BASE_DIR)/build
 RUST_BUILD_DIR := $(BUILD_DIR)/rust
 PYTHON_BUILD_DIR := $(BUILD_DIR)/python
+CPP_BUILD_DIR := $(BUILD_DIR)/python
 
 FILES=$(wildcard proto/astarteplatform/msghub/*.proto)
 
@@ -50,9 +52,12 @@ RUST_CODEGEN_SCRIPT=$(CANONICAL_CURDIR)/scripts/rust_codegen.sh
 PYTHON_LANG=$(PYTHON_BUILD_DIR)/astarteplatform
 PYTHON_CODEGEN_SCRIPT=$(CANONICAL_CURDIR)/scripts/python_codegen.sh
 
+CPP_LANG=$(CPP_BUILD_DIR)/astarteplatform
+CPP_CODEGEN_SCRIPT=$(CANONICAL_CURDIR)/scripts/cpp_codegen.sh
+
 # This is our default rule, so must come first
 .PHONY: all
-all : $(RUST_LANG) $(PYTHON_LANG)
+all : $(RUST_LANG) $(PYTHON_LANG) $(CPP_LANG)
 
 $(RUST_LANG): $(FILES) $(RUST_CODEGEN_SCRIPT)
 		mkdir -p $(RUST_BUILD_DIR)
@@ -62,6 +67,10 @@ $(PYTHON_LANG): $(FILES) $(PYTHON_CODEGEN_SCRIPT)
 		mkdir -p $(PYTHON_BUILD_DIR)
 		$(PYTHON_CODEGEN_SCRIPT) codegen $(PROTO_DIR) $(PYTHON_LANG_DIR) $(PYTHON_BUILD_DIR) $(DL_DIR)
 
+$(CPP_LANG): $(FILES) $(CPP_CODEGEN_SCRIPT)
+		mkdir -p $(CPP_BUILD_DIR)
+		$(CPP_CODEGEN_SCRIPT) codegen $(PROTO_DIR) $(CPP_LANG_DIR) $(CPP_BUILD_DIR)
+
 .PHONY: protoc-check
 protoc-check: $(PROTOC_CHECK_SCRIPT)
 		$(PROTOC_CHECK_SCRIPT)
@@ -72,6 +81,9 @@ rust: protoc-check $(RUST_LANG)
 .PHONY: python
 python: protoc-check $(PYTHON_LANG)
 
+.PHONY: cpp
+cpp: protoc-check $(CPP_LANG)
+
 .PHONY: rust-install
 rust-install: $(RUST_LANG)
 		$(RUST_CODEGEN_SCRIPT) install_code $(RUST_BUILD_DIR) $(RUST_LANG_DIR)
@@ -80,6 +92,10 @@ rust-install: $(RUST_LANG)
 python-install: $(PYTHON_LANG)
 		$(PYTHON_CODEGEN_SCRIPT) install_code $(PYTHON_BUILD_DIR) $(PYTHON_LANG_DIR)
 
+.PHONY: cpp-install
+cpp-install: $(CPP_LANG)
+		$(CPP_CODEGEN_SCRIPT) install_code $(CPP_BUILD_DIR) $(CPP_LANG_DIR)
+
 .PHONY: install
 install: rust-install python-install
 
@@ -95,6 +111,10 @@ rust-dirclean:
 python-dirclean:
 		rm -rf $(PYTHON_BUILD_DIR)
 
+.PHONY: cpp-dirclean
+cpp-dirclean:
+		rm -rf $(CPP_BUILD_DIR)
+
 .PHONY: help
 help:
 		@echo 'Cleaning:'

cpp/CMakeLists.txt

@@ -0,0 +1,75 @@
+
+# Minimum CMake required
+cmake_minimum_required(VERSION 3.15)
+
+# Project
+project(astarte-msg-hub-proto)
+
+# Protobuf
+set(protobuf_MODULE_COMPATIBLE TRUE)
+find_package(Protobuf CONFIG REQUIRED)
+message(STATUS "Using protobuf ${protobuf_VERSION}")
+
+# Protobuf-compiler
+set(_PROTOBUF_PROTOC $<TARGET_FILE:protobuf::protoc>)
+
+# gRPC
+find_package(gRPC CONFIG REQUIRED)
+message(STATUS "Using gRPC ${gRPC_VERSION}")
+set(_GRPC_GRPCPP gRPC::grpc++)
+set(_GRPC_CPP_PLUGIN_EXECUTABLE $<TARGET_FILE:gRPC::grpc_cpp_plugin>)
+
+# Output directory
+if(NOT EXISTS "${OUT_FOLDER}")
+  set(OUT_FOLDER "${CMAKE_CURRENT_LIST_DIR}")
+endif()
+
+
+# Directory containing proto files
+get_filename_component(proto_inc_path "${CMAKE_CURRENT_LIST_DIR}/../proto" ABSOLUTE)
+# Collect all .proto files
+file(GLOB_RECURSE proto_files "${proto_inc_path}/astarteplatform/msghub/*.proto")
+
+# Prepare the list of generated source and header files
+set(proto_srcs)
+set(proto_hdrs)
+set(grpc_srcs)
+set(grpc_hdrs)
+
+foreach(proto_file ${proto_files})
+    get_filename_component(proto_name ${proto_file} NAME_WE)
+
+    # Output paths
+    set(out_proto_src "${OUT_FOLDER}/astarteplatform/msghub/${proto_name}.pb.cc")
+    set(out_proto_hdr "${OUT_FOLDER}/astarteplatform/msghub/${proto_name}.pb.h")
+    set(out_grpc_src "${OUT_FOLDER}/astarteplatform/msghub/${proto_name}.grpc.pb.cc")
+    set(out_grpc_hdr "${OUT_FOLDER}/astarteplatform/msghub/${proto_name}.grpc.pb.h")
+
+    # Add generated files to the lists
+    list(APPEND proto_srcs "${out_proto_src}")
+    list(APPEND proto_hdrs "${out_proto_hdr}")
+    list(APPEND grpc_srcs "${out_grpc_src}")
+    list(APPEND grpc_hdrs "${out_grpc_hdr}")
+
+    # Generated sources
+    add_custom_command(
+        OUTPUT "${out_proto_src}" "${out_proto_hdr}" "${out_grpc_src}" "${out_grpc_hdr}"
+        COMMAND ${_PROTOBUF_PROTOC}
+        ARGS --grpc_out "${OUT_FOLDER}"
+            --cpp_out "${OUT_FOLDER}"
+            -I "${proto_inc_path}"
+            --plugin=protoc-gen-grpc="${_GRPC_CPP_PLUGIN_EXECUTABLE}"
+            "${proto_file}"
+      DEPENDS "${proto_file}")
+endforeach()
+
+# Add the generated files to the build
+add_library(astarte_message_hub_proto SHARED ${proto_srcs} ${proto_hdrs} ${grpc_srcs} ${grpc_hdrs})
+# Include generated *.pb.h files
+target_include_directories(astarte_message_hub_proto PUBLIC ${OUT_FOLDER})
+# Link the libraries together
+target_link_libraries(astarte_message_hub_proto
+  absl::check
+  ${_REFLECTION}
+  ${_GRPC_GRPCPP}
+  ${_PROTOBUF_LIBPROTOBUF})

cpp/README.md

@@ -0,0 +1,18 @@
+# Generated proto files for C++
+
+## Installing gRPC
+
+Follow the [online guide](https://grpc.io/docs/languages/cpp/quickstart/#install-grpc) to install
+gRPC.
+
+## Compilation of the .proto files
+
+The CMake scripts in this folder make it possible to generate the C++ classes and structures
+starting from the .proto files.
+```sh
+mkdir -p ./cmake/build
+pushd ./cmake/build
+cmake ../..
+make
+popd
+```

scripts/cpp_codegen.sh

@@ -0,0 +1,43 @@
+#!/usr/bin/env bash
+
+# Copyright 2024 SECO Mind Srl
+# SPDX-License-Identifier: Apache-2.0
+
+set -eEuo pipefail
+
+codegen () {
+    PROTO_DIR=$1
+    PROJECT_DIR=$2
+    OUT_DIR=$3
+
+    # Remove old code
+    if [ -d "$OUT_DIR/astarteplatform" ]; then
+        rm -r "$OUT_DIR/astarteplatform"
+    fi
+
+    mkdir -p $PROJECT_DIR/cmake/build
+    pushd $PROJECT_DIR/cmake/build
+    cmake -DOUT_FOLDER:STRING=$OUT_DIR ../..
+    make
+    popd
+
+    }
+
+install_code (){
+      OUT_DIR=$1
+      INSTALL_DIR=$2
+
+      # Check if the directory exists and is not empty
+      if [ -d "$INSTALL_DIR"/astarteplatform/msghub ] && [ "$(ls -A "$INSTALL_DIR"/astarteplatform/msghub)" ]; then
+        rm -v "$INSTALL_DIR"/astarteplatform/msghub/*
+      fi
+
+      install -d "$INSTALL_DIR"/astarteplatform/msghub
+      install -m 644 "$OUT_DIR"/astarteplatform/msghub/* "$INSTALL_DIR"/astarteplatform/msghub
+}
+
+if [ "$1" = "codegen" ]; then
+  codegen "$2" "$3" "$4"
+elif [ "$1" = "install_code" ]; then
+    install_code "$2" "$3"
+fi