Auto download the C driver if it is not already installed

Author: Kyle Kloberdanz

.evergreen/compile.sh

@@ -52,7 +52,7 @@ esac
 . .evergreen/find_cmake.sh
 
 cd build
-"$CMAKE" -G "$GENERATOR" "-DCMAKE_BUILD_TYPE=${BUILD_TYPE}" -DMONGOCXX_ENABLE_SLOW_TESTS=ON -DENABLE_UNINSTALL=ON "$@" ..
+"$CMAKE" -G "$GENERATOR" "-DCMAKE_BUILD_TYPE=${BUILD_TYPE}" -DMONGOCXX_ENABLE_SLOW_TESTS=ON -DENABLE_UNINSTALL=ON -DBUILD_TESTS=ON "$@" ..
 "$CMAKE" --build . --config $BUILD_TYPE -- $CMAKE_BUILD_OPTS
 "$CMAKE" --build . --config $BUILD_TYPE --target install -- $CMAKE_BUILD_OPTS
 "$CMAKE" --build . --config $BUILD_TYPE --target $CMAKE_EXAMPLES_TARGET -- $CMAKE_BUILD_OPTS

CMakeLists.txt

@@ -40,6 +40,61 @@ else()
   message(WARNING "Unknown compiler... recklessly proceeding without a version check")
 endif()
 
+set(LIBMONGOC_REQUIRED_VERSION 1.22.1) # TODO: update to 1.24.0 once released.
+set(LIBMONGOC_REQUIRED_ABI_VERSION 1.0)
+
+set(NEED_DOWNLOAD_C_DRIVER false CACHE INTERNAL "")
+if(TARGET mongoc_shared OR TARGET mongoc_static)
+  # If these targets exist, then libmongoc has already been included as a project
+  # sub-directory
+  message ("found libmongoc targets declared in current build scope; version not checked")
+
+  if(NOT MONGOCXX_LINK_WITH_STATIC_MONGOC)
+    set(libmongoc_target mongoc_shared)
+  else()
+    set(libmongoc_target mongoc_static)
+  endif()
+
+  if(MONGOCXX_BUILD_STATIC)
+    set(mongocxx_pkg_dep "find_dependency(mongoc-1.0 REQUIRED)")
+  endif()
+else()
+    find_package(mongoc-${LIBMONGOC_REQUIRED_ABI_VERSION} ${LIBMONGOC_REQUIRED_VERSION} QUIET)
+    if(mongoc-${LIBMONGOC_REQUIRED_ABI_VERSION}_FOUND)
+        message("already found libmongoc, don't need to download it.")
+    else()
+        set(NEED_DOWNLOAD_C_DRIVER true CACHE INTERNAL "")
+    endif()
+endif()
+
+if (${NEED_DOWNLOAD_C_DRIVER})
+    message("No Mongo C Driver path provided via CMAKE_PREFIX_PATH, will download a release from the internet.")
+    include(FetchContent)
+    include(ExternalProject)
+
+    # Declare mongo-c-driver as a dependency
+    FetchContent_Declare(
+      mongo-c-driver
+      GIT_REPOSITORY https://github.com/kkloberdanz/mongo-c-driver.git
+      GIT_TAG 1.24.0
+    )
+
+    FetchContent_MakeAvailable(mongo-c-driver)
+
+    # Set the installation directory for mongo-c-driver
+    set(MONGOC_INSTALL_DIR ${CMAKE_BINARY_DIR}/mongo-c-driver-install)
+
+    # Build mongo-c-driver using ExternalProject
+    ExternalProject_Add(mongo-c-driver-build
+        SOURCE_DIR ${mongo-c-driver_SOURCE_DIR}
+        BINARY_DIR ${CMAKE_BINARY_DIR}/mongo-c-driver-build
+        INSTALL_DIR ${MONGOC_INSTALL_DIR}
+        CMAKE_ARGS -DCMAKE_INSTALL_PREFIX=${MONGOC_INSTALL_DIR}
+    )
+    file(REMOVE ${mongo-c-driver_SOURCE_DIR}/build/generate-uninstall.sh)
+    file(REMOVE ${mongo-c-driver_SOURCE_DIR}/build/generate-uninstall.cmd)
+endif()
+
 # All of our target compilers support the deprecated
 # attribute. Normally, we would just let the GenerateExportHeader
 # subsystem do this via configure check, but there appears to be a

cmake/BsoncxxUtil.cmake

@@ -62,6 +62,12 @@ function(bsoncxx_add_library TARGET OUTPUT_NAME LINK_TYPE)
         EXPORT_FILE_NAME config/export.hpp
         STATIC_DEFINE BSONCXX_STATIC
     )
+
+    if (${NEED_DOWNLOAD_C_DRIVER})
+        add_dependencies(${TARGET} mongo-c-driver-build)
+        target_include_directories(${TARGET} PRIVATE ${MONGOC_INSTALL_DIR}/include/libmongoc-1.0/mongoc/)
+        target_include_directories(${TARGET} PRIVATE ${MONGOC_INSTALL_DIR}/include/libbson-1.0/bson/)
+    endif()
 endfunction(bsoncxx_add_library)
 
 # Install the specified forms of the bsoncxx library (i.e., shared and/or static)

cmake/MongocxxUtil.cmake

@@ -46,6 +46,12 @@ function(mongocxx_add_library TARGET OUTPUT_NAME LINK_TYPE)
         EXPORT_FILE_NAME config/export.hpp
         STATIC_DEFINE MONGOCXX_STATIC
     )
+
+    if (${NEED_DOWNLOAD_C_DRIVER})
+        add_dependencies(${TARGET} mongo-c-driver-build)
+        target_include_directories(${TARGET} PRIVATE ${MONGOC_INSTALL_DIR}/include/libmongoc-1.0/mongoc/)
+        target_include_directories(${TARGET} PRIVATE ${MONGOC_INSTALL_DIR}/include/libbson-1.0/bson/)
+    endif()
 endfunction(mongocxx_add_library)
 
 # Install the specified forms of the mongocxx library (i.e., shared and/or static)

src/bsoncxx/test/CMakeLists.txt

@@ -12,24 +12,26 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-include_directories(
-    ${MONGO_CXX_DRIVER_SOURCE_DIR}/src/third_party/catch/include
-)
+if (BUILD_TESTS STREQUAL "ON")
+    include_directories(
+        ${MONGO_CXX_DRIVER_SOURCE_DIR}/src/third_party/catch/include
+    )
 
-file (GLOB src_bsoncxx_test_DIST_cpps RELATIVE ${CMAKE_CURRENT_SOURCE_DIR} *.cpp)
+    file (GLOB src_bsoncxx_test_DIST_cpps RELATIVE ${CMAKE_CURRENT_SOURCE_DIR} *.cpp)
 
-add_executable(test_bson
-    ${THIRD_PARTY_SOURCE_DIR}/catch/main.cpp
-    ${src_bsoncxx_test_DIST_cpps}
-)
+    add_executable(test_bson
+        ${THIRD_PARTY_SOURCE_DIR}/catch/main.cpp
+        ${src_bsoncxx_test_DIST_cpps}
+    )
 
-target_link_libraries(test_bson bsoncxx_testing ${libbson_target})
-target_include_directories(test_bson PRIVATE ${libbson_include_directories})
-target_compile_definitions(test_bson PRIVATE ${libbson_definitions})
+    target_link_libraries(test_bson bsoncxx_testing ${libbson_target})
+    target_include_directories(test_bson PRIVATE ${libbson_include_directories})
+    target_compile_definitions(test_bson PRIVATE ${libbson_definitions})
 
-add_test(bson test_bson)
+    add_test(bson test_bson)
 
-set_dist_list (src_bsoncxx_test_DIST
-   CMakeLists.txt
-   ${src_bsoncxx_test_DIST_cpps}
-)
+    set_dist_list (src_bsoncxx_test_DIST
+        CMakeLists.txt
+        ${src_bsoncxx_test_DIST_cpps}
+    )
+endif()

src/mongocxx/CMakeLists.txt

@@ -29,9 +29,6 @@ message ("mongocxx version: ${MONGOCXX_VERSION}")
 set(MONGOCXX_INLINE_NAMESPACE "v${MONGOCXX_ABI_VERSION}")
 set(MONGOCXX_HEADER_INSTALL_DIR "${CMAKE_INSTALL_INCLUDEDIR}/mongocxx/${MONGOCXX_INLINE_NAMESPACE}" CACHE INTERNAL "")
 
-set(LIBMONGOC_REQUIRED_VERSION 1.22.1) # TODO: update to 1.24.0 once released.
-set(LIBMONGOC_REQUIRED_ABI_VERSION 1.0)
-
 set(mongocxx_pkg_dep "")
 
 if(TARGET mongoc_shared OR TARGET mongoc_static)
@@ -69,7 +66,10 @@ else()
       find_package(libmongoc-${LIBMONGOC_REQUIRED_ABI_VERSION} ${LIBMONGOC_REQUIRED_VERSION} REQUIRED)
       message ("found libmongoc version ${MONGOC_VERSION}")
       set(libmongoc_target ${MONGOC_LIBRARIES})
-      set(libmongoc_include_directories ${MONGOC_INCLUDE_DIRS})
+      set(libmongoc_include_directories ${MONGOC_INCLUDE_DIRS}
+        ${MONGOC_INSTALL_DIR}/include/libmongoc-1.0/mongoc/
+        ${MONGOC_INSTALL_DIR}/include/libbson-1.0/bson/
+      )
       set(libmongoc_definitions ${MONGOC_DEFINITIONS})
       if(MONGOCXX_BUILD_STATIC)
         set(mongocxx_pkg_dep "find_dependency(libmongoc-1.0 REQUIRED)")
@@ -78,7 +78,10 @@ else()
       find_package(libmongoc-static-${LIBMONGOC_REQUIRED_ABI_VERSION} ${LIBMONGOC_REQUIRED_VERSION} REQUIRED)
       message ("found libmongoc version ${MONGOC_STATIC_VERSION}")
       set(libmongoc_target ${MONGOC_STATIC_LIBRARIES})
-      set(libmongoc_include_directories ${MONGOC_STATIC_INCLUDE_DIRS})
+      set(libmongoc_include_directories ${MONGOC_STATIC_INCLUDE_DIRS}
+        ${MONGOC_INSTALL_DIR}/include/libmongoc-1.0/mongoc/
+        ${MONGOC_INSTALL_DIR}/include/libbson-1.0/bson/
+      )
       set(libmongoc_definitions ${MONGOC_STATIC_DEFINITIONS})
       if(MONGOCXX_BUILD_STATIC)
         set(mongocxx_pkg_dep "find_dependency(libmongoc-static-1.0 REQUIRED)")