feat(cmake): Generate pkg-config files

Fixes: #447

.github/workflows/cmake-ci.yml

@@ -86,24 +86,44 @@ jobs:
       - name: "Install Release"
         run: cmake --install ${{ github.workspace }}/_build --config Release
 
-      - name: "Configure import for Unix with internal dependencies"
+      - name: "Configure CMake import for Unix with internal dependencies"
         if: matrix.dependencies == 'submodule' && runner.os != 'Windows'
-        run: cmake -Dprometheus-cpp_DIR=${{ github.workspace }}/_install/lib/cmake/prometheus-cpp -DCMAKE_CONFIGURATION_TYPES='Release;Debug' -G"Ninja Multi-Config" -S ${{ github.workspace }}/cmake/project-import -B ${{ github.workspace }}/_import
+        run: cmake -Dprometheus-cpp_DIR=${{ github.workspace }}/_install/lib/cmake/prometheus-cpp -DCMAKE_CONFIGURATION_TYPES='Release;Debug' -G"Ninja Multi-Config" -S ${{ github.workspace }}/cmake/project-import-cmake -B ${{ github.workspace }}/_import_cmake
 
-      - name: "Configure import for Windows with internal dependencies"
+      - name: "Configure CMake import for Windows with internal dependencies"
         if: matrix.dependencies == 'submodule' && runner.os == 'Windows'
-        run: cmake -Dprometheus-cpp_DIR=${{ github.workspace }}/_install/lib/cmake/prometheus-cpp -S ${{ github.workspace }}/cmake/project-import -B ${{ github.workspace }}/_import
+        run: cmake -Dprometheus-cpp_DIR=${{ github.workspace }}/_install/lib/cmake/prometheus-cpp -S ${{ github.workspace }}/cmake/project-import-cmake -B ${{ github.workspace }}/_import_cmake
 
-      - name: "Configure import for Unix with vcpkg dependencies"
+      - name: "Configure CMake import for Unix with vcpkg dependencies"
         if: matrix.dependencies == 'vcpkg' && runner.os != 'Windows'
-        run: cmake -Dprometheus-cpp_DIR=${{ github.workspace }}/_install/lib/cmake/prometheus-cpp "-DCMAKE_TOOLCHAIN_FILE=${VCPKG_INSTALLATION_ROOT}/scripts/buildsystems/vcpkg.cmake" -DCMAKE_CONFIGURATION_TYPES='Release;Debug' -G"Ninja Multi-Config" -S ${{ github.workspace }}/cmake/project-import -B ${{ github.workspace }}/_import
+        run: cmake -Dprometheus-cpp_DIR=${{ github.workspace }}/_install/lib/cmake/prometheus-cpp "-DCMAKE_TOOLCHAIN_FILE=${VCPKG_INSTALLATION_ROOT}/scripts/buildsystems/vcpkg.cmake" -DCMAKE_CONFIGURATION_TYPES='Release;Debug' -G"Ninja Multi-Config" -S ${{ github.workspace }}/cmake/project-import-cmake -B ${{ github.workspace }}/_import_cmake
 
-      - name: "Configure import for Windows with vcpkg dependencies"
+      - name: "Configure CMake import for Windows with vcpkg dependencies"
         if: matrix.dependencies == 'vcpkg' && runner.os == 'Windows'
-        run: cmake -Dprometheus-cpp_DIR=${{ github.workspace }}/_install/lib/cmake/prometheus-cpp "-DCMAKE_TOOLCHAIN_FILE=${Env:VCPKG_INSTALLATION_ROOT}\scripts\buildsystems\vcpkg.cmake" -S ${{ github.workspace }}/cmake/project-import -B ${{ github.workspace }}/_import
+        run: cmake -Dprometheus-cpp_DIR=${{ github.workspace }}/_install/lib/cmake/prometheus-cpp "-DCMAKE_TOOLCHAIN_FILE=${Env:VCPKG_INSTALLATION_ROOT}\scripts\buildsystems\vcpkg.cmake" -S ${{ github.workspace }}/cmake/project-import-cmake -B ${{ github.workspace }}/_import_cmake
 
-      - name: "Build import Debug"
-        run: cmake --build ${{ github.workspace }}/_import --config Debug
+      - name: "Build CMake import Debug"
+        run: cmake --build ${{ github.workspace }}/_import_cmake --config Debug
 
-      - name: "Build import Release"
-        run: cmake --build ${{ github.workspace }}/_import --config Release
+      - name: "Build CMake import Release"
+        run: cmake --build ${{ github.workspace }}/_import_cmake --config Release
+
+      - name: "Configure for Unix Shared Libs with internal dependencies"
+        if: matrix.dependencies == 'submodule' && runner.os != 'Windows'
+        run: cmake -DUSE_THIRDPARTY_LIBRARIES=ON -DBUILD_SHARED_LIBS=ON -DCMAKE_INSTALL_PREFIX=${{ github.workspace }}/_install_shared -DENABLE_WARNINGS_AS_ERRORS=ON -DENABLE_COMPRESSION=OFF -DENABLE_PUSH=OFF -DCMAKE_DEBUG_POSTFIX=_d  -GNinja -S ${{ github.workspace }} -B ${{ github.workspace }}/_build_shared
+
+      - name: "Build for Unix Shared Libs"
+        if: matrix.dependencies == 'submodule' && runner.os != 'Windows'
+        run: cmake --build ${{ github.workspace }}/_build_shared
+
+      - name: "Install for Unix Shared Libs"
+        if: matrix.dependencies == 'submodule' && runner.os != 'Windows'
+        run: cmake --install ${{ github.workspace }}/_build_shared
+
+      - name: "Configure pkg-config import for Unix"
+        if: matrix.dependencies == 'submodule' && runner.os != 'Windows'
+        run: cmake -DCMAKE_PREFIX_PATH=${{ github.workspace }}/_install_shared -GNinja -S ${{ github.workspace }}/cmake/project-import-pkgconfig -B ${{ github.workspace }}/_import_pkgconfig
+
+      - name: "Build pkg-config import for Unix"
+        if: matrix.dependencies == 'submodule' && runner.os != 'Windows'
+        run: cmake --build ${{ github.workspace }}/_import_pkgconfig

CMakeLists.txt

@@ -4,7 +4,11 @@ if(POLICY CMP0091)
   cmake_policy(SET CMP0091 NEW) # recognize CMAKE_MSVC_RUNTIME_LIBRARY
 endif()
 
-project(prometheus-cpp VERSION 0.12.1)
+project(prometheus-cpp
+  VERSION 0.12.1
+  DESCRIPTION "Prometheus Client Library for Modern C++"
+  HOMEPAGE_URL "https://github.com/jupp0r/prometheus-cpp"
+)
 
 include(GenerateExportHeader)
 include(GNUInstallDirs)
@@ -20,6 +24,7 @@ option(ENABLE_TESTING "Build tests" ON)
 option(USE_THIRDPARTY_LIBRARIES "Use 3rdParty submodules" ON)
 option(THIRDPARTY_CIVETWEB_WITH_SSL "Enable SSL support for embedded civetweb source code")
 option(OVERRIDE_CXX_STANDARD_FLAGS "Force building with -std=c++11 even if the CXXLFAGS are configured differently" ON)
+option(GENERATE_PKGCONFIG "Generate and install pkg-config files" ON)
 
 if(OVERRIDE_CXX_STANDARD_FLAGS)
   set(CMAKE_CXX_STANDARD 11)
@@ -121,8 +126,7 @@ install(
 
 if(CMAKE_CURRENT_SOURCE_DIR STREQUAL CMAKE_SOURCE_DIR)
   set(CPACK_PACKAGE_CONTACT "prometheus-cpp@@noreply.github.com")
-  set(CPACK_PACKAGE_DESCRIPTION "C++ library for Prometheus exporters")
-  set(CPACK_PACKAGE_HOMEPAGE_URL "https://github.com/jupp0r/prometheus-cpp")
+  set(CPACK_PACKAGE_DESCRIPTION "${PROJECT_DESCRIPTION}")
   set(CPACK_PACKAGE_RELOCATABLE OFF)
   set(CPACK_PACKAGE_VENDOR "The prometheus-cpp authors")
 

cmake/project-import-pkgconfig/CMakeLists.txt

@@ -0,0 +1,21 @@
+cmake_minimum_required(VERSION 3.12 FATAL_ERROR)
+
+project(prometheus-cpp-import)
+
+set(CMAKE_CXX_STANDARD 11)
+
+find_package(PkgConfig REQUIRED)
+
+pkg_check_modules(PROMETHEUS_CPP_CORE REQUIRED prometheus-cpp-core)
+pkg_check_modules(PROMETHEUS_CPP_PUSH IMPORTED_TARGET prometheus-cpp-push)
+pkg_check_modules(PROMETHEUS_CPP_PULL IMPORTED_TARGET prometheus-cpp-pull)
+
+if(PROMETHEUS_CPP_PUSH_FOUND)
+  add_executable(sample-client sample_client.cc)
+  target_link_libraries(sample-client PRIVATE PkgConfig::PROMETHEUS_CPP_PUSH)
+endif()
+
+if(PROMETHEUS_CPP_PULL_FOUND)
+  add_executable(sample-server sample_server.cc)
+  target_link_libraries(sample-server PRIVATE PkgConfig::PROMETHEUS_CPP_PULL)
+endif()

cmake/project-import-pkgconfig/sample_client.cc

@@ -0,0 +1 @@
+../../push/tests/integration/sample_client.cc

cmake/project-import-pkgconfig/sample_server.cc

@@ -0,0 +1 @@
+../../pull/tests/integration/sample_server.cc

cmake/prometheus-cpp-core.pc.in

@@ -0,0 +1,12 @@
+prefix=@CMAKE_INSTALL_PREFIX@
+exec_prefix=${prefix}
+includedir=${prefix}/@CMAKE_INSTALL_INCLUDEDIR@
+libdir=${exec_prefix}/@CMAKE_INSTALL_LIBDIR@
+
+Name: @PROJECT_NAME@-core
+Description: @PROJECT_DESCRIPTION@
+URL: @PROJECT_HOMEPAGE_URL@
+Version: @PROJECT_VERSION@
+Cflags: -I${includedir}
+Libs: -L${libdir} -l@PROJECT_NAME@-core
+Libs.private: @CMAKE_THREAD_LIBS_INIT@ @PKGCONFIG_LIBS@ @PKGCONFIG_LIBATOMIC@

cmake/prometheus-cpp-pull.pc.in

@@ -0,0 +1,14 @@
+prefix=@CMAKE_INSTALL_PREFIX@
+exec_prefix=${prefix}
+includedir=${prefix}/@CMAKE_INSTALL_INCLUDEDIR@
+libdir=${exec_prefix}/@CMAKE_INSTALL_LIBDIR@
+
+Name: @PROJECT_NAME@-pull
+Description: @PROJECT_DESCRIPTION@
+URL: @PROJECT_HOMEPAGE_URL@
+Version: @PROJECT_VERSION@
+Requires: @PROJECT_NAME@-core
+Requires.private: @PKGCONFIG_REQUIRES@
+Cflags: -I${includedir}
+Libs: -L${libdir} -l@PROJECT_NAME@-pull
+Libs.private: @CMAKE_THREAD_LIBS_INIT@ @PKGCONFIG_LIBS@

cmake/prometheus-cpp-push.pc.in

@@ -0,0 +1,14 @@
+prefix=@CMAKE_INSTALL_PREFIX@
+exec_prefix=${prefix}
+includedir=${prefix}/@CMAKE_INSTALL_INCLUDEDIR@
+libdir=${exec_prefix}/@CMAKE_INSTALL_LIBDIR@
+
+Name: @PROJECT_NAME@-push
+Description: @PROJECT_DESCRIPTION@
+URL: @PROJECT_HOMEPAGE_URL@
+Version: @PROJECT_VERSION@
+Requires: @PROJECT_NAME@-core
+Requires.private: @PKGCONFIG_REQUIRES@
+Cflags: -I${includedir}
+Libs: -L${libdir} -l@PROJECT_NAME@-push
+Libs.private: @CMAKE_THREAD_LIBS_INIT@ @PKGCONFIG_LIBS@

core/CMakeLists.txt

@@ -1,4 +1,3 @@
-
 add_library(core
   src/check_names.cc
   src/counter.cc
@@ -62,6 +61,23 @@ install(
   DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}
 )
 
+if(GENERATE_PKGCONFIG)
+  if(HAVE_CXX_LIBATOMIC)
+    string(PKGCONFIG_LIBATOMIC -latomic)
+  endif()
+
+  configure_file(
+    ${PROJECT_SOURCE_DIR}/cmake/prometheus-cpp-core.pc.in
+    ${CMAKE_CURRENT_BINARY_DIR}/prometheus-cpp-core.pc
+    @ONLY
+  )
+
+  install(
+    FILES ${CMAKE_CURRENT_BINARY_DIR}/prometheus-cpp-core.pc
+    DESTINATION ${CMAKE_INSTALL_LIBDIR}/pkgconfig
+  )
+endif()
+
 if(ENABLE_TESTING)
   add_subdirectory(tests)
 endif()

pull/CMakeLists.txt

@@ -7,6 +7,7 @@ if(USE_THIRDPARTY_LIBRARIES)
   )
 else()
   find_package(civetweb CONFIG REQUIRED)
+  string(APPEND PKGCONFIG_LIBS " -lcivetweb-cpp -lcivetweb")
 
   # work-around https://github.com/civetweb/civetweb/pull/918
   if(WIN32 AND NOT TARGET WINSOCK::WINSOCK)
@@ -17,6 +18,7 @@ endif()
 
 if(ENABLE_COMPRESSION)
   find_package(ZLIB REQUIRED)
+  string(APPEND PKGCONFIG_REQUIRES " zlib")
 endif()
 
 add_library(pull
@@ -85,6 +87,19 @@ install(
   DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}
 )
 
+if(GENERATE_PKGCONFIG)
+  configure_file(
+    ${PROJECT_SOURCE_DIR}/cmake/prometheus-cpp-pull.pc.in
+    ${CMAKE_CURRENT_BINARY_DIR}/prometheus-cpp-pull.pc
+    @ONLY
+  )
+
+  install(
+    FILES ${CMAKE_CURRENT_BINARY_DIR}/prometheus-cpp-pull.pc
+    DESTINATION ${CMAKE_INSTALL_LIBDIR}/pkgconfig
+  )
+endif()
+
 if(ENABLE_TESTING)
   add_library(pull_internal_headers INTERFACE)
   add_library(${PROJECT_NAME}::pull_internal_headers ALIAS pull_internal_headers)

push/CMakeLists.txt

@@ -1,4 +1,3 @@
-
 find_package(CURL REQUIRED)
 
 add_library(push
@@ -49,6 +48,21 @@ install(
   DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}
 )
 
+if(GENERATE_PKGCONFIG)
+  string(APPEND PKGCONFIG_REQUIRES " libcurl")
+
+  configure_file(
+    ${PROJECT_SOURCE_DIR}/cmake/prometheus-cpp-push.pc.in
+    ${CMAKE_CURRENT_BINARY_DIR}/prometheus-cpp-push.pc
+    @ONLY
+  )
+
+  install(
+    FILES ${CMAKE_CURRENT_BINARY_DIR}/prometheus-cpp-push.pc
+    DESTINATION ${CMAKE_INSTALL_LIBDIR}/pkgconfig
+  )
+endif()
+
 if(ENABLE_TESTING)
   add_subdirectory(tests)
 endif()