1
研究背景
go程序部署时，直接将编译好的文件在服务器上运行即可，一般无需安装所依赖的第三方库。
Linux下部署分为以下几种方式：
使用nohup 命令
使用 Supervisord管理
使用systemd管理
windows下部署方式：
注册成windows服务，方便进行管理
其实golang自己也可以实现以服务的形式常驻后台。
现在介绍一个包 github.com/kardianos/service ，它可以让 go 程序支持在不同系统上作为服务：注册，卸载，启动，停止。
2
安装部署
go get github.com/kardianos/service
3
使用方法
通过两个例子，我们来了解其用法。
3.1 示例程序: simple
package main
import (
"log"
"github.com/kardianos/service"
)
var logger service.Logger //service的日志对象
type program struct{} //定义结构体，并实现service.Interface的start和stop接口
func (p *program) Start(s service.Service) error {
// Start should not block. Do the actual work async.
go p.run()
return nil
}
func (p *program) run() {
// Do work here
}
func (p *program) Stop(s service.Service) error {
// Stop should not block. Return with a few seconds.
return nil
}
func main() {
svcConfig := &service.Config{
Name: "GoServiceExampleSimple",
DisplayName: "Go Service Example",
Description: "This is an example Go service.",
}
prg := &program{}
s, err := service.New(prg, svcConfig)
if err != nil {
log.Fatal(err)
}
logger, err = s.Logger(nil)
if err != nil {
log.Fatal(err)
}
err = s.Run()
if err != nil {
logger.Error(err)
}
}
套路如下：
一、定义结构体program，并实现service的接口函数Start和Stop
需要实现的service接口Interface如下：
type Interface interface {
// Start provides a place to initiate the service. The service doesn't
// signal a completed start until after this function returns, so the
// Start function must not take more then a few seconds at most.
Start(s Service) error
// Stop provides a place to clean up program execution before it is terminated.
// It should not take more then a few seconds to execute.
// Stop should not call os.Exit directly in the function.
Stop(s Service) error
}
二、初始化service.Config结构体，并调用service.New创建service对象
三、为service对象设置日志Logger
四、调用service的Run方法来运行程序
3.2 示例程序2
package main
import (
"encoding/json"
"flag"
"fmt"
"log"
"os"
"os/exec"
"path/filepath"
"github.com/kardianos/service"
)
// Config is the runner app config structure.
type Config struct {
Name, DisplayName, Description string
Dir string
Exec string
Args []string
Env []string
Stderr, Stdout string
}
var logger service.Logger
type program struct {
exit chan struct{}
service service.Service
*Config
cmd *exec.Cmd
}
func (p *program) Start(s service.Service) error {
// Look for exec.
// Verify home directory.
fullExec, err := exec.LookPath(p.Exec)
if err != nil {
return fmt.Errorf("Failed to find executable %q: %v", p.Exec, err)
}
p.cmd = exec.Command(fullExec, p.Args...)
p.cmd.Dir = p.Dir
p.cmd.Env = append(os.Environ(), p.Env...)
go p.run()
return nil
}
func (p *program) run() {
logger.Info("Starting ", p.DisplayName)
defer func() {
if service.Interactive() {
p.Stop(p.service)
} else {
p.service.Stop()
}
}()
if p.Stderr != "" {
f, err := os.OpenFile(p.Stderr, os.O_CREATE|os.O_APPEND|os.O_WRONLY, 0777)
if err != nil {
logger.Warningf("Failed to open std err %q: %v", p.Stderr, err)
return
}
defer f.Close()
p.cmd.Stderr = f
}
if p.Stdout != "" {
f, err := os.OpenFile(p.Stdout, os.O_CREATE|os.O_APPEND|os.O_WRONLY, 0777)
if err != nil {
logger.Warningf("Failed to open std out %q: %v", p.Stdout, err)
return
}
defer f.Close()
p.cmd.Stdout = f
}
err := p.cmd.Run()
if err != nil {
logger.Warningf("Error running: %v", err)
}
return
}
func (p *program) Stop(s service.Service) error {
close(p.exit)
logger.Info("Stopping ", p.DisplayName)
if p.cmd.Process != nil {
p.cmd.Process.Kill()
}
if service.Interactive() {
os.Exit(0)
}
return nil
}
func getConfigPath() (string, error) {
fullexecpath, err := os.Executable()
if err != nil {
return "", err
}
dir, execname := filepath.Split(fullexecpath)
ext := filepath.Ext(execname)
name := execname[:len(execname)-len(ext)]
return filepath.Join(dir, name+".json"), nil
}
func getConfig(path string) (*Config, error) {
f, err := os.Open(path)
if err != nil {
return nil, err
}
defer f.Close()
conf := &Config{}
r := json.NewDecoder(f)
err = r.Decode(&conf) //将json字符串转为Config对象
if err != nil {
return nil, err
}
return conf, nil
}
func main() {
svcFlag := flag.String("service", "", "Control the system service.")
flag.Parse()
configPath, err := getConfigPath() //获取配置文件路径
if err != nil {
log.Fatal(err)
}
config, err := getConfig(configPath) //获取配置
if err != nil {
log.Fatal(err)
}
//初始化service配置属性
svcConfig := &service.Config{
Name: config.Name,
DisplayName: config.DisplayName,
Description: config.Description,
}
prg := &program{
exit: make(chan struct{}),
Config: config,
}
s, err := service.New(prg, svcConfig)
if err != nil {
log.Fatal(err)
}
prg.service = s
errs := make(chan error, 5)
logger, err = s.Logger(errs)
if err != nil {
log.Fatal(err)
}
go func() {
for {
err := <-errs
if err != nil {
log.Print(err)
}
}
}()
if len(*svcFlag) != 0 {
//通过命令行参数来控制服务
err := service.Control(s, *svcFlag)
if err != nil {
log.Printf("Valid actions: %q\n", service.ControlAction)
log.Fatal(err)
}
return
}
err = s.Run()
if err != nil {
logger.Error(err)
}
}
其配置文件runner.json如下
{
"Name": "builder",
"DisplayName": "Go Builder",
"Description": "Run the Go Builder",
"Dir": "C:\\dev\\go\\src",
"Exec": "C:\\windows\\system32\\cmd.exe",
"Args": ["/C","C:\\dev\\go\\src\\all.bat"],
"Env": [
"PATH=C:\\TDM-GCC-64\\bin;C:\\Program Files (x86)\\Git\\cmd",
"GOROOT_BOOTSTRAP=C:\\dev\\go_ready",
"HOMEDRIVE=C:",
"HOMEPATH=\\Documents and Settings\\Administrator"
],
"Stderr": "C:\\builder_err.log",
"Stdout": "C:\\builder_out.log"
}
可将service相关的配置信息存储到配置文件中。通过读取配置文件中的配置信息来生成service。
4
接口定义（源码剖析）
这个库有两个接口
4.1 Service接口
其中Service接口有Run、Start、Stop、Restart、Install、Uninstall等核心方法可实现，以对应服务的运行、启动、停止、重启、安装、卸载操作。
type Service interface {
// Run should be called shortly after the program entry point.
// After Interface.Stop has finished running, Run will stop blocking.
// After Run stops blocking, the program must exit shortly after.
Run() error
// Start signals to the OS service manager the given service should start.
Start() error
// Stop signals to the OS service manager the given service should stop.
Stop() error
// Restart signals to the OS service manager the given service should stop then start.
Restart() error
// Install setups up the given service in the OS service manager. This may require
// greater rights. Will return an error if it is already installed.
Install() error
// Uninstall removes the given service from the OS service manager. This may require
// greater rights. Will return an error if the service is not present.
Uninstall() error
// Opens and returns a system logger. If the user program is running
// interactively rather then as a service, the returned logger will write to
// os.Stderr. If errs is non-nil errors will be sent on errs as well as
// returned from Logger's functions.
Logger(errs chan<- error) (Logger, error)
// SystemLogger opens and returns a system logger. If errs is non-nil errors
// will be sent on errs as well as returned from Logger's functions.
SystemLogger(errs chan<- error) (Logger, error)
// String displays the name of the service. The display name if present,
// otherwise the name.
String() string
}
其中aixService、freebsdService、solarisService、systemd、sysv、upstart、windowsService分别对应不同的操作系统aix，freebsd，solaris，linux，windows操作系统上的服务。
4.2 Interface接口
Interface接口中有Start和Stop
type Interface interface {
// Start provides a place to initiate the service. The service doesn't not
// signal a completed start until after this function returns, so the
// Start function must not take more then a few seconds at most.
Start(s Service) error
// Stop provides a place to clean up program execution before it is terminated.
// It should not take more then a few seconds to execute.
// Stop should not call os.Exit directly in the function.
Stop(s Service) error
}
《酷Go推荐》招募：
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新的库，并且知道怎么用。
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