go学习

1. 字符串处理

1.1 去除空白符

// this data still needs to be parsed
		lines = strings.Split(r.Output, "\n")

		for i = range lines {
			lines[i] = strings.TrimSpace(lines[i])
		}

		// trim away empty lines
		lines = lines[1 : len(lines)-1]

2. 自定义命令一（cobra）

├─cmd
│  ├─main.go

cmd/main.go

package main

import (
	"fmt"
	"os"
	"time"
	"go.uber.org/zap"
	"github.com/spf13/cobra"
)

var (
	LogAction string
	Date      string
	logger *zap.Logger
)

func InitLogger() {
	logger, _ = zap.NewProduction()
}

// cli 命令基于 https://github.com/spf13/cobra 封装
// RootCmd represents the base command when called without any subcommands

var RootCmd = &cobra.Command{
	Use:   "Cli",
	Short: "A brief description of your application",
	Long: `调用方法：
			1.进入项目根目录（Ginkeleton）。 
			2.执行 go  run  cmd/main.go  -h  //可以查看使用指南
			3.执行 go  run  cmd/main.go  -A update  // 通过 Action 动作执行相应的命令`,
	Run: func(cmd *cobra.Command, args []string) {
		//args  参数表示非flag（也叫作位置参数），该参数默认会作为一个数组存储。
		//fmt.Println(args)
		start(LogAction, Date)  // 调用业务函数
	},
}

func Execute() {
	if err := RootCmd.Execute(); err != nil {
		fmt.Println(err)
		os.Exit(1)
	}
}

func init() {
	InitLogger()
	RootCmd.Flags().StringVarP(&LogAction, "logAction", "A", "insert", "-A 指定参数动作,例如：-A insert ")
	RootCmd.Flags().StringVarP(&Date, "date", "D", time.Now().Format("2006-01-02"), "-D 指定日期,例如：-D  2021-09-13")

}

// 自定义业务函数
func start(actionName, Date string) {
	switch actionName {
	case "insert":
		logger.Info("insert 参数执行对应业务逻辑,Date参数值：" + Date)
	case "update":
		logger.Info("update 参数执行对应业务逻辑,Date参数值：" + Date)
	}

}

func main() {
	Execute()
	defer logger.Sync()
}

自定义命令二（cli）

main.go

package main

import (
  "fmt"
  "github.com/urfave/cli/v2"
)

func main() {
  myApp := cli.NewApp()
  myApp.Name = "kcptun"
  myApp.Usage = "client(with SMUX)"
  myApp.Version = "1.0"
  myApp.Flags = []cli.Flag{
    cli.StringFlag{
      Name:  "localaddr,l",  # 参数名
      Value: ":12948",       # 默认值
      Usage: "local listen address",  # 用法介绍
      Required: true,   # 必要参数
      DefaultText :"random",  # 提示信息中显示的默认值，覆盖Value值，更于理解
    },
    cli.StringFlag{
      Name:  "remoteaddr, r",
      Value: "vps:29900",
      Usage: "kcp server address",
    },
    cli.StringFlag{
      Name:   "key",
      Value:  "it's a secrect",
      Usage:  "pre-shared secret between client and server",
      EnvVar: "KCPTUN_KEY",  # 从环境变量读取
    },
  }
  myApp.Action = func(c *cli.Context) error {
    localaddr := c.String("localaddr")
    remoteAddr := c.String("remoteaddr")
    key := c.String("key")
    runMyFunc(localaddr, remoteAddr, key)
  }

  err := myApp.Run(os.Args)
  if err != nil {
    log.Fatal(err)
  }
}

func runMyFunc(localaddr, remoteAddr, key string){
  fmt.Printf("hello")
  fmt.Printf(localaddr, remoteAddr, key)
}