再来一篇，Go+Vue前后端分离设计实践

github.com/gin-gonic/gin v1.9.0
github.com/go-sql-driver/mysql v1.7.1
github.com/spf13/cast v1.5.0

var Db *sql.DB

const (
	DbDriver   = "mysql"
	DbUserName = "root"
	DbPasswd   = "12345"
	DbHost     = "127.0.0.1"
	DbPort     = 3306
	DbName     = "test"
)

func InitDB() {
	var err error
	Db, err = sql.Open(DbDriver, fmt.Sprintf("%s:%s@tcp(%s:%d)/%s?charset=utf8",
		DbUserName, DbPasswd, DbHost, DbPort, DbName))
	if err != nil {
		panic(err)
	}
	Db.SetConnMaxLifetime(100 * time.Second)
	Db.SetMaxOpenConns(10)
	Db.SetMaxIdleConns(16)
}

type Student struct {
	Id   int32  `json:"id"`
	Name string `json:"name"`
	Age  int8   `json:"age"`
}

var DefaultStudentDb *StudentDb

func NewStudentDb() *StudentDb {
	return &StudentDb{TbName: "student", Db: config.Db}
}

type StudentDb struct {
	TbName string
	Db     *sql.DB
}

func (s *StudentDb) Save(student Student) error {
	stmt, err := s.Db.Prepare(fmt.Sprintf("INSERT INTO %s(name,age) VALUES(?,?)", s.TbName))
	if err != nil {
		return err
	}
	if _, err = stmt.Exec(student.Name, student.Age); err != nil {
		return err
	}
	return nil
}

func (s *StudentDb) GetAll() ([]Student, error) {
	students := make([]Student, 0)
	rows, err := s.Db.Query(fmt.Sprintf("SELECT id,name,age from %s", s.TbName))
	if err != nil {
		return nil, err
	}
	for rows.Next() {
		var student Student
		if err := rows.Scan(&student.Id, &student.Name, &student.Age); err != nil {
			return nil, err
		}
		students = append(students, student)
	}
	return students, nil
}

func (s *StudentDb) GetOne(id int32) (Student, error) {
	var student Student
	rows, err := s.Db.Query(fmt.Sprintf("SELECT id,name,age from %s WHERE id=%d", s.TbName, id))
	if err != nil {
		return student, err
	}
	if rows.Next() {
		if err := rows.Scan(&student.Id, &student.Name, &student.Age); err != nil {
			return student, err
		}
	}
	return student, nil
}

func (s *StudentDb) Remove(id int32) error {
	stmt, err := s.Db.Prepare(fmt.Sprintf("DELETE FROM %s WHERE id=%d", s.TbName, id))
	if err != nil {
		return err
	}
	if _, err := stmt.Exec(); err != nil {
		return err
	}
	return nil
}

func (s *StudentDb) Update(student Student) error {
	stmt, err := s.Db.Prepare(fmt.Sprintf("UPDATE %s SET name=?,age=? WHERE id=?", s.TbName))
	if err != nil {
		return err
	}
	if _, err := stmt.Exec(student.Name, student.Age, student.Id); err != nil {
		return err
	}
	return nil
}

func Update(c *gin.Context) {
	student := model.Student{}
	if err := c.BindJSON(&student); err != nil {
		fmt.Println(err)
		c.JSON(http.StatusInternalServerError, -1)
		return
	}
	if err := model.DefaultStudentDb.Update(student); err != nil {
		c.JSON(http.StatusInternalServerError, -1)
		return
	}
	c.JSON(http.StatusOK, 1)
}

func Remove(c *gin.Context) {
	id := c.Param("id")
	if err := model.DefaultStudentDb.Remove(cast.ToInt32(id)); err != nil {
		c.JSON(http.StatusInternalServerError, -1)
		return
	}
	c.JSON(http.StatusOK, 1)
}

func FindById(c *gin.Context) {
	id := c.Param("id")
	student, err := model.DefaultStudentDb.GetOne(cast.ToInt32(id))
	if err != nil {
		c.JSON(http.StatusInternalServerError, -1)
		return
	}
	c.JSON(http.StatusOK, student)
}

func FindAll(c *gin.Context) {
	students, err := model.DefaultStudentDb.GetAll()
	if err != nil {
		c.JSON(http.StatusInternalServerError, -1)
		return
	}
	c.JSON(http.StatusOK, students)
}

func Save(c *gin.Context) {
	student := model.Student{}
	if err := c.BindJSON(&student); err != nil {
		c.JSON(http.StatusInternalServerError, -1)
		return
	}
	if err := model.DefaultStudentDb.Save(student); err != nil {
		c.JSON(http.StatusInternalServerError, -1)
		return
	}
	c.JSON(http.StatusOK, 1)
}

const (
	Port = 8081
)

func RunHttp() error {
	r := gin.Default()
	r.Use(CorsConfig())
	router := r.Group("/student")
	{
		router.POST("/save", Save)
		router.GET("/findAll", FindAll)
		router.GET("/findById/:id", FindById)
		router.POST("/update", Update)
		router.DELETE("/remove/:id", Remove)
	}
	return r.Run(fmt.Sprintf("127.0.0.1:%d", Port))
}

//解决跨域
func CorsConfig() gin.HandlerFunc {
	return func(c *gin.Context) {
		c.Header("Access-Control-Allow-Origin", "*") // 可将将 * 替换为指定的域名
		c.Header("Access-Control-Allow-Methods", "POST, GET, OPTIONS, PUT, DELETE, UPDATE")
		c.Header("Access-Control-Allow-Headers", "*")
		c.Header("Access-Control-Expose-Headers", "*")
		c.Header("Access-Control-Allow-Credentials", "true")
		c.Writer.Header().Set("Access-Control-Max-Age", "86400")
		if c.Request.Method == http.MethodOptions {
			c.AbortWithStatus(200)
		} else {
			c.Next()
		}
	}
}

package main

import (
	"back_go/config"
	"back_go/model"
	"back_go/web"
)

func main() {
	config.InitDB()
	model.DefaultStudentDb = model.NewStudentDb()
	web.RunHttp()
}