在后端生产环境中,为了方便定位问题,我们需要根据一个binary文件获取其对应的git信息,包括编译出该binary所用的代码分支、commitid、时间戳、commit message等。但是随着代码版本的升级,这些git信息也会随之变化。有没有办法在每次编译binary的时候,将git信息动态注入到其中呢?答案是有!. B7 ~9 K& Z' }0 e p! \
创建以下几个文件,创建头文件version.hh,内容如下,其中声明了表示git信息的数据结构:0 v8 Q E; ^( Q/ \% Q6 S
#pragma once
#include <string>
namespace my_app
{
struct Version
{
static const std::string GIT_SHA1;
static const std::string GIT_BRANCH;
static const std::string GIT_DATE;
static const std::string GIT_COMMIT_SUBJECT;
};
}
创建模板文件,version.cc.in,其中定义了Version中静态变量的值。其中@XX@表示该变量通过cmake注入:% X/ J% b/ s' l' F6 u
#include "version.hh" r7 C0 d" @( n1 ?. M
#include "version.hh"
using namespace my_app;
const std::string Version::GIT_SHA1 = "@GIT_SHA1@";
const std::string Version::GIT_BRANCH = "@GIT_BRANCH@";
const std::string Version::GIT_DATE = "@GIT_DATE@";
const std::string Version::GIT_COMMIT_SUBJECT = "@GIT_COMMIT_SUBJECT@";
创建main.cc
0 | ^! }6 h2 P2 ~- g% J #include <iostream>
#include "version.hh"
using namespace my_app;
int main() {
std::cout << "building sha1: " << Version::GIT_SHA1 << std::endl;
std::cout << "building branch: " << Version::GIT_BRANCH << std::endl;
std::cout << "building date: " << Version::GIT_DATE << std::endl;
std::cout << "building commit subject: " << Version::GIT_COMMIT_SUBJECT << std::endl;
return 0;
创建CMakeLists.txt- x \9 M; v* [
cmake_minimum_required(VERSION 3.5)
project (inject_git)
set(GIT_EXECUTABLE /usr/bin/git)
# 执行git rev-parse HEAD, 生成commitid, 将结果保存于变量GIT_SHA1
execute_process(COMMAND
"${GIT_EXECUTABLE}" rev-parse HEAD
WORKING_DIRECTORY "${CMAKE_SOURCE_DIR}"
OUTPUT_VARIABLE GIT_SHA1
ERROR_QUIET OUTPUT_STRIP_TRAILING_WHITESPACE)
# 执行git rev-parse --abbrev-ref HEAD, 生成branch name, 将结果保存于变量GIT_BRANCH
execute_process(COMMAND
"${GIT_EXECUTABLE}" rev-parse --abbrev-ref HEAD
WORKING_DIRECTORY "${CMAKE_SOURCE_DIR}"
OUTPUT_VARIABLE GIT_BRANCH
ERROR_QUIET OUTPUT_STRIP_TRAILING_WHITESPACE)
# 执行git log -1 --format=%ad --date=local, 生成提交日期, 将结果保存于变量GIT_DATE
execute_process(COMMAND
"${GIT_EXECUTABLE}" log -1 --format=%ad --date=local
WORKING_DIRECTORY "${CMAKE_SOURCE_DIR}"
OUTPUT_VARIABLE GIT_DATE
ERROR_QUIET OUTPUT_STRIP_TRAILING_WHITESPACE)
# 执行git log -1 --format=%s, 生成提交日志, 将结果保存于变量GIT_COMMIT_SUBJECT
execute_process(COMMAND
"${GIT_EXECUTABLE}" log -1 --format=%s
WORKING_DIRECTORY "${CMAKE_SOURCE_DIR}"
OUTPUT_VARIABLE GIT_COMMIT_SUBJECT
ERROR_QUIET OUTPUT_STRIP_TRAILING_WHITESPACE)
# 上述变量初始化后,将其注入到模板文件version.cc.in中,生成version.cc
configure_file("${CMAKE_CURRENT_SOURCE_DIR}/version.cc.in" "${CMAKE_CURRENT_BINARY_DIR}/version.cc" @ONLY)
set(SOURCES
main.cc
version.cc
)
# 由version.cc和main.cc生成二进制
add_executable(inject_git ${SOURCES})
二进制文件执行结果如下: I# [. [0 K7 e" ^" K! ?5 ]9 [* ]% X
$ ./inject_git # q! O2 F' {" w) B' w
building sha1: 74b25fc30d18001f72ec0cf0495165441df40a094 t0 e1 z4 j9 f4 p2 M$ C
building branch: master
- D. q6 s+ s# { building date: Fri May 28 14:49:16 20218 D O8 }; b- K4 R. q% D
building commit subject: add again