Enable building otel-cpp as external project on Linux

Author: duncanpo

CMakeLists.txt

@@ -57,12 +57,19 @@ if(DEFINED OTEL_CPP_PREFIX)
 else()
     set(OTEL_CPP_PREFIX ${CMAKE_BINARY_DIR}/otel-cpp)
 endif()
+
+if(WITH_OTLP_GRPC)
+    set(OTEL_CPP_CXX_STANDARD 14)  # Abseil requires at least Cxx14
+else()
+    set(OTEL_CPP_CXX_STANDARD 11)
+endif()
+
 ExternalProject_Add(
     ${OTEL_CPP_PROJECT_NAME}
     GIT_REPOSITORY ${OTEL_CPP_GIT_REPOSITORY}
     GIT_TAG ${OTEL_CPP_GIT_TAG}
     PREFIX ${OTEL_CPP_PREFIX}
-    CMAKE_ARGS -DCMAKE_POSITION_INDEPENDENT_CODE=ON -DWITH_OTLP_HTTP=${WITH_OTLP_HTTP} -DWITH_OTLP_GRPC=${WITH_OTLP_GRPC} -DBUILD_TESTING=OFF -DWITH_BENCHMARK=OFF -DOPENTELEMETRY_INSTALL=ON -DCMAKE_TOOLCHAIN_FILE=${CMAKE_TOOLCHAIN_FILE}
+    CMAKE_ARGS -DCMAKE_POSITION_INDEPENDENT_CODE=ON -DWITH_OTLP_HTTP=${WITH_OTLP_HTTP} -DWITH_OTLP_GRPC=${WITH_OTLP_GRPC} -DBUILD_TESTING=OFF -DWITH_BENCHMARK=OFF -DOPENTELEMETRY_INSTALL=ON -DCMAKE_TOOLCHAIN_FILE=${CMAKE_TOOLCHAIN_FILE} -DCMAKE_CXX_STANDARD=${OTEL_CPP_CXX_STANDARD}
     INSTALL_DIR ${OTEL_CPP_PREFIX}
     INSTALL_COMMAND ${CMAKE_COMMAND} --install . --prefix ${OTEL_CPP_PREFIX}
 )
@@ -163,27 +170,33 @@ if(WITH_OTLP_GRPC)
     endif()
 endif()
 
+if(WIN32)
+    set(OTEL_PROTO_LIBRARY_SUFFIX ${CMAKE_STATIC_LIBRARY_SUFFIX})
+else()
+    set(OTEL_PROTO_LIBRARY_SUFFIX ${CMAKE_SHARED_LIBRARY_SUFFIX})
+endif()
+
 target_compile_options(${OPENTELEMETRY_PROXY_LIBRARY_NAME} PRIVATE ${OTLP_MACROS})
 
 # link against OpenTelemetry-cpp libraries and their dependencies
-target_link_libraries(${OPENTELEMETRY_PROXY_LIBRARY_NAME} PRIVATE ${OTEL_CPP_PREFIX}/lib/opentelemetry_common${CMAKE_LINK_LIBRARY_SUFFIX}
-	${OTEL_CPP_PREFIX}/lib/opentelemetry_otlp_recordable${CMAKE_LINK_LIBRARY_SUFFIX}
-	${OTEL_CPP_PREFIX}/lib/opentelemetry_proto${CMAKE_LINK_LIBRARY_SUFFIX}
-	${OTEL_CPP_PREFIX}/lib/opentelemetry_resources${CMAKE_LINK_LIBRARY_SUFFIX}
-	${OTEL_CPP_PREFIX}/lib/opentelemetry_trace${CMAKE_LINK_LIBRARY_SUFFIX}
-	${OTEL_CPP_PREFIX}/lib/opentelemetry_version${CMAKE_LINK_LIBRARY_SUFFIX}
-	${OTEL_CPP_PREFIX}/lib/opentelemetry_logs${CMAKE_LINK_LIBRARY_SUFFIX}
+target_link_libraries(${OPENTELEMETRY_PROXY_LIBRARY_NAME} PRIVATE ${OTEL_CPP_PREFIX}/lib/${CMAKE_STATIC_LIBRARY_PREFIX}opentelemetry_common${CMAKE_STATIC_LIBRARY_SUFFIX}
+	${OTEL_CPP_PREFIX}/lib/${CMAKE_STATIC_LIBRARY_PREFIX}opentelemetry_otlp_recordable${CMAKE_STATIC_LIBRARY_SUFFIX}
+        ${OTEL_CPP_PREFIX}/lib/${CMAKE_SHARED_LIBRARY_PREFIX}opentelemetry_proto${OTEL_PROTO_LIBRARY_SUFFIX}
+	${OTEL_CPP_PREFIX}/lib/${CMAKE_STATIC_LIBRARY_PREFIX}opentelemetry_resources${CMAKE_STATIC_LIBRARY_SUFFIX}
+	${OTEL_CPP_PREFIX}/lib/${CMAKE_STATIC_LIBRARY_PREFIX}opentelemetry_trace${CMAKE_STATIC_LIBRARY_SUFFIX}
+	${OTEL_CPP_PREFIX}/lib/${CMAKE_STATIC_LIBRARY_PREFIX}opentelemetry_version${CMAKE_STATIC_LIBRARY_SUFFIX}
+	${OTEL_CPP_PREFIX}/lib/${CMAKE_STATIC_LIBRARY_PREFIX}opentelemetry_logs${CMAKE_STATIC_LIBRARY_SUFFIX}
 	${Protobuf_LIBRARIES})
 if(WITH_OTLP_HTTP)
-    target_link_libraries(${OPENTELEMETRY_PROXY_LIBRARY_NAME} PRIVATE ${OTEL_CPP_PREFIX}/lib/opentelemetry_exporter_otlp_http${CMAKE_LINK_LIBRARY_SUFFIX}
-	    ${OTEL_CPP_PREFIX}/lib/opentelemetry_exporter_otlp_http_client${CMAKE_LINK_LIBRARY_SUFFIX}
-	    ${OTEL_CPP_PREFIX}/lib/opentelemetry_http_client_curl${CMAKE_LINK_LIBRARY_SUFFIX}
+    target_link_libraries(${OPENTELEMETRY_PROXY_LIBRARY_NAME} PRIVATE ${OTEL_CPP_PREFIX}/lib/${CMAKE_STATIC_LIBRARY_PREFIX}opentelemetry_exporter_otlp_http${CMAKE_STATIC_LIBRARY_SUFFIX}
+	    ${OTEL_CPP_PREFIX}/lib/${CMAKE_STATIC_LIBRARY_PREFIX}opentelemetry_exporter_otlp_http_client${CMAKE_STATIC_LIBRARY_SUFFIX}
+	    ${OTEL_CPP_PREFIX}/lib/${CMAKE_STATIC_LIBRARY_PREFIX}opentelemetry_http_client_curl${CMAKE_STATIC_LIBRARY_SUFFIX}
 	    ${CURL_LIBRARIES})
 endif()
 if(WITH_OTLP_GRPC)
-    target_link_libraries(${OPENTELEMETRY_PROXY_LIBRARY_NAME} PRIVATE ${OTEL_CPP_PREFIX}/lib/opentelemetry_exporter_otlp_grpc${CMAKE_LINK_LIBRARY_SUFFIX}
-	    ${OTEL_CPP_PREFIX}/lib/opentelemetry_exporter_otlp_grpc_client${CMAKE_LINK_LIBRARY_SUFFIX}
-	    ${OTEL_CPP_PREFIX}/lib/opentelemetry_proto_grpc${CMAKE_LINK_LIBRARY_SUFFIX}
+    target_link_libraries(${OPENTELEMETRY_PROXY_LIBRARY_NAME} PRIVATE ${OTEL_CPP_PREFIX}/lib/${CMAKE_STATIC_LIBRARY_PREFIX}opentelemetry_exporter_otlp_grpc${CMAKE_STATIC_LIBRARY_SUFFIX}
+	    ${OTEL_CPP_PREFIX}/lib/${CMAKE_STATIC_LIBRARY_PREFIX}opentelemetry_exporter_otlp_grpc_client${CMAKE_STATIC_LIBRARY_SUFFIX}
+            ${OTEL_CPP_PREFIX}/lib/${CMAKE_SHARED_LIBRARY_PREFIX}opentelemetry_proto_grpc${OTEL_PROTO_LIBRARY_SUFFIX}
 	    gRPC::grpc++
 	    absl::synchronization)
 endif()
@@ -193,6 +206,7 @@ if(UNIX AND NOT APPLE AND NOT CYGWIN)
     set(OPENTELEMETRY_PROXY_LINK_OPTIONS -Wl,--whole-archive 
 	"${OTEL_CPP_PREFIX}/lib/libopentelemetry_trace.a"
 	"${OTEL_CPP_PREFIX}/lib/libopentelemetry_common.a"
+	"${OTEL_CPP_PREFIX}/lib/libopentelemetry_otlp_recordable.a"
         ${ABSL_LIBRARIES}
         ${UPB_LIBRARIES} -Wl,--no-whole-archive)
     target_link_options(${OPENTELEMETRY_PROXY_LIBRARY_NAME} PRIVATE ${OPENTELEMETRY_PROXY_LINK_OPTIONS})