之前，已经讲过很多Golang的东西，比如基础语法，mysql的使用，redis的使用等等，感兴趣的可以看看以前的文章，https://www.cnblogs.com/zhangweizhong/category/1275863.html，
今天就用从头写一个完整的go的示例项目吧。
本项目完全使用原生开发，没有使用任何WEB框架和ORM。虽然大家对mvc 呀，三层架构已经很了解了。但是，我还是想从头写一个完整的示例项目。这样大家有一个更深刻的了解，这样以后介绍web框架，orm框架的时候，学习起来应该会简单一点。
项目架构
下图这种架构模式相信大家应该十分清楚
Controller组合封装
Controller"基类"封装
package framework
type Controller struct {
Data interface{}
}
UserController定义了用户注册，登录和查询等简单的三个接口
package controller import (
"net/http"
"micro-cloud/service"
"micro-cloud/utils"
"micro-cloud/framework"
) /**
* r.PostFormValue : 可以解析 Post/PUT Content-Type=application/x-www-form-urlencoded 或 Content-Type=multipart/form-data
*/ type UserConterller struct { } var userService = new(service.UserService) func (p *UserConterller) Router(router *framework.RouterHandler) {
router.Router("/register", p.register)
router.Router("/login", p.login)
router.Router("/findAll", p.findAll)
} //POST Content-Type=application/x-www-form-urlencoded
func (p *UserConterller) register(w http.ResponseWriter, r *http.Request) {
username := r.PostFormValue("username")
password := r.PostFormValue("password")
if utils.Empty(username) || utils.Empty(password) {
microcloud.ResultFail(w, "username or password can not be empty")
return
}
id := userService.Insert(username, password)
if id <= 0 {
microcloud.ResultFail(w, "register fail")
return
}
microcloud.ResultOk(w, "register success")
} //POST Content-Type=application/x-www-form-urlencoded
func (p *UserConterller) login(w http.ResponseWriter, r *http.Request) {
username := r.PostFormValue("username")
password := r.PostFormValue("password")
if utils.Empty(username) || utils.Empty(password) {
microcloud.ResultFail(w, "username or password can not be empty")
return
}
users := userService.SelectUserByName(username)
if len(users) == 0 {
microcloud.ResultFail(w, "user does not exist")
return
}
if users[0].Password != password {
microcloud.ResultFail(w, "password error")
return
} microcloud.ResultOk(w, "login success")
} // GET/POST
func (p *UserConterller) findAll(w http.ResponseWriter, r *http.Request) {
users := userService.SelectAllUser()
framework.ResultJsonOk(w, users)
}
数据访问层
package dao import (
"micro-cloud/model"
"fmt"
) type UserDao struct {
} func (p *UserDao) Insert(user *model.User) int64 {
result, err := framework.DB.Exec("INSERT INTO user(`username`,`password`,`create_time`) value(?,?,?)", user.Username, user.Password, user.CreateTime)
if err != nil {
fmt.Println("Insert error")
return
}
id, err := result.LastInsertId()
if err != nil {
fmt.Println("Insert error")
return
}
return id
} func (p *UserDao) SelectUserByName(username string) []model.User {
rows, err := framework.DB.Query("SELECT * FROM user WHERE username = ?", username)
if err != nil {
fmt.Println("selectuserbyname error")
return nil
}
var users []model.User
for rows.Next() {
var user model.User
err := rows.Scan(&user.ID, &user.Username, &user.Password, &user.CreateTime)
if err != nil {
fmt.Println("selectuserbyname error")
continue
}
users = append(users, user)
}
rows.Close()
return users
} func (p *UserDao) SelectAllUser() []model.User {
rows, err := framework.DB.Query("SELECT * FROM user")
if err != nil {
fmt.Println("SelectAllUser error")
return nil
}
var users []model.User
for rows.Next() {
var user model.User
err := rows.Scan(&user.ID, &user.Username, &user.Password, &user.CreateTime)
if err != nil {
fmt.Println("SelectAllUser error")
continue
}
users = append(users, user)
}
rows.Close()
return users
}
实体层
package model
import "time"
type User struct {
ID uint `json:"id"`
Username string `json:"username"`
Password string `json:"-"`
CreateTime time.Time `json:"create_time"`
}
database
数据库操作类的实现
package microcloud import (
"database/sql"
"log"
"strings"
_ "github.com/go-sql-driver/mysql"
) //数据库的配置
const (
username = "admin"
password = "123456"
ip = "10.2.1.5"
port = "3306"
dbName = "microcloud"
driverName = "mysql"
) //DB数据库连接池
var DB *sql.DB func InitDB() {
//构建连接："用户名:密码@tcp(IP:端口)/数据库?charset=uft8"
//注意：要想解析time.Time类型，必须要设置parseTime=True
path := strings.Join([]string{username, ":", password, "@tcp(", ip, ":", port, ")/", dbName, "?charset=utf8&parseTime=True&loc=Local"}, "")
//打开数据库，前者是驱动名，所以要导入:_"github.com/go-sql-driver/mysql"
DB, _ = sql.Open(driverName, path)
//设置数据库最大连接数
DB.SetConnMaxLifetime(100)
//设置数据库最大闲置连接数
DB.SetMaxIdleConns(10)
//验证连接
if err := DB.Ping(); err != nil {
log.Panic(err)
}
log.Println("database connect success")
} func CreateTable() {
userTable := "CREATE TABLE IF NOT EXISTS `user`(" +
"`id` INT UNSIGNED AUTO_INCREMENT," +
"`username` VARCHAR(20) NOT NULL," +
"`password` VARCHAR(40) NOT NULL," +
"`create_time` DATETIME," +
"PRIMARY KEY ( `id` )" +
")ENGINE=InnoDB DEFAULT CHARSET=utf8;" _, err := DB.Exec(userTable)
if err != nil {
log.Panic(err)
}
}
http
http server的实现
server := &http.Server{
Addr: ":8215",
Handler: microcloud.Router,
ReadTimeout: * time.Second,
}
RegiterRouter(microcloud.Router)
err := server.ListenAndServe()
if err != nil {
log.Panic(err)
}
Router
路由处理的实现，其实也就是一个转发的功能
type RouterHandler struct {
}
var mux = make(map[string]func(http.ResponseWriter,*http.Request))
func (p *RouterHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
fmt.Println(r.URL.Path)
if fun, ok := mux[r.URL.Path]; ok {
fun(w, r)
return
}
//静态资源
if strings.HasPrefix(r.URL.Path,constant.STATIC_BAES_PATH){
if fun, ok := mux[constant.STATIC_BAES_PATH]; ok {
fun(w, r)
return
}
}
http.Error(w, "error URL:"+r.URL.String(), http.StatusBadRequest)
}
func (p *RouterHandler) Router(relativePath string, handler func(http.ResponseWriter, *http.Request)) {
mux[relativePath] = handler
}
演示
执行 go run main.go 之后，打开Postman，调相关的接口
以下就是访问API的请求与响应
/findAll 接口
/register 接口
最后
以上，用Go语言实现webapi 的例子，已经介绍完了，虽然比较简单，session，权限验证等都没有加。但是最主要的功能已经讲完了，感兴趣的可以从头编写下相关的代码。
完整例子下载：microcloud.rar