simple golang cli

package main

import (
 	"bufio"
 	"errors"
 	"fmt"
 	"os"
 	"strconv"
 	"strings"
)

//一行数据库记录
type Row struct {
 	ID          int
 	Name        string
 	Age         int
 	Description string
}

//一张数据表
type Table struct {
 	data            []Row
 	AutoIncrementID int
}

func initTableData() []Row {
 	return make([]Row, 0)
}

func NewTable() *Table {

 	table := new(Table)
 	table.data = initTableData()
 	return table
}

func (table *Table) Insert(row *Row) error {
 	table.AutoIncrementID++
 	row.ID = table.AutoIncrementID
 	table.data = append(table.data, *row)
 	return nil
}

func (table *Table) Delete(id int) error {
 	found := false
 	for k, v := range table.data {
 		if v.ID == id {
 			found = true
 			if k < len(table.data) {
 				table.data = append(table.data[:k], table.data[k+1:]...)
 			} else {
 				table.data = append(table.data[:k])
 			}
 		}
 	}
 	if found {
 		return nil
 	}
 	return errors.New("No Rows Found.")
}

func (table *Table) FlushAll() error {
 	table.data = initTableData()
 	return nil
}

func (table *Table) GetAll() []Row {
 	return table.data
}

//命令的签名契约
type HandleFunc func(*Table, string) error

//注册的命令列表
var commandHandle map[string]HandleFunc

//当前打开的表
var globalTable *Table

/**
 Input 模块，用于监听用户输入，并且进行命令分发。
**/
func InputLoop() {
 	scanner := bufio.NewScanner(os.Stdin)
 	for scanner.Scan() {
 		line := scanner.Text()
 		arr := strings.Split(line, " ")
 		handle, ok := commandHandle[strings.ToLower(arr[0])]
 		if !ok {
 			fmt.Println("unsupported command:", arr[0])
 			continue
 		}
 		err := handle(globalTable, strings.Trim(line[len(arr[0]):], " "))
 		if err != nil {
 			fmt.Println("Command Get Errors:", err.Error())
 		} else {
 			fmt.Println("Operator OK.")
 		}
 	}
}

func Add(table *Table, input string) error {

 	arr := strings.Split(input, ",")
 	if len(arr) == 1 {
 		return errors.New("输入格式不正确")
 	}

 	age, err := strconv.Atoi(arr[1])
 	if err != nil {
 		return errors.New("输入格式不正确")
 	}

 	newRow := Row{
 		Name:        arr[1],
 		Age:         age,
 		Description: arr[2],
 	}

 	return table.Insert(&newRow)
}

func Delete(table *Table, input string) error {

 	id, err := strconv.Atoi(input)
 	if err != nil {
 		return errors.New("输入格式不正确" + input)
 	}
 	return table.Delete(id)
}

func ShowList(table *Table, input string) error {
 	pFmt := "%-5d %-10s %-3d %-32s\n"

 	fmt.Printf("%-5s %-10s %-3s %-32s\n", "id", "name", "age", "description")
 	fmt.Println()

 	for _, v := range table.GetAll() {
 		fmt.Printf(pFmt, v.ID, v.Name, v.Age, v.Description)
 	}

 	return nil
}

func FlushAll(table *Table, input string) error {
 	return table.FlushAll()
}

func Exit(table *Table, input string) error {
 	os.Exit(1)
 	return nil
}

func Help(table *Table, input string) error {

 	helper :=
 		`
----------------------------------------------------------------------------------
====================== Weixinhost Developer Database =============================
----------------------------------------------------------------------------------

help:
add name,age,descriotion  添加一条数据 (eg:add MiskoLee,26,Nice)
delete id 根据Id删除一条数据 (eg: delete 1)
flushall 清空数据表
exit 退出程序


`

 	fmt.Println(helper)

 	return nil
}

func init() {

 	commandHandle = make(map[string]HandleFunc, 0)
 	commandHandle["add"] = Add
 	commandHandle["delete"] = Delete
 	commandHandle["showlist"] = ShowList
 	commandHandle["flushall"] = FlushAll
 	commandHandle["exit"] = Exit
 	commandHandle["help"] = Help
}

func main() {
 	Help(nil, "")
 	globalTable = NewTable()
 	InputLoop()
}