go项目实现mysql接入及web api的操作方法
作者：香吧香
这篇文章主要介绍了go项目实现mysql接入以及web api,本文通过实例代码给大家介绍的非常详细，对大家的学习或工作具有一定的参考借鉴价值，需要的朋友可以参考下
创建go项目，并在go项目中接入mysql，将mysql的配置项单独整理放到一个胚子和文件中，支持项目启动时，通过加载配置文件中的值，然后创建数据库连接。
之后使用net/http相关的库，创建路由，并在路由中通过不同的http方法，实现mysql连接的test数据库中users表的增删改查 的 web api
1.在idea中创建go项目
其目录文件结构如下
2.创建配置文件，并初始化数据库
在项目的根目录下创建数据库的配置文件：config.json
{
"host": "192.168.118.46",
"port": 3306,
"user": "root",
"password": "root",
"dbname": "terra_no"
}创建数据库以及表，并插入数据
CREATE TABLE `users` ( `id` int(11) NOT NULL AUTO_INCREMENT, `name` varchar(12) COLLATE utf8mb4_unicode_ci DEFAULT NULL, `age` int(12) DEFAULT '18', PRIMARY KEY (`id`) ); insert into users value (1,"aa",12); insert into users value (2,"bb",22);
3.创建加载mysql，并创建数据库连接的类
在项目的根目录下创建database目录，之后创建 mysql.go 文件
package database
import (
"database/sql"
"encoding/json"
"fmt"
_ "github.com/go-sql-driver/mysql"
"io/ioutil"
"log"
)
type MySQLConfig struct {
Host string `json:"host"`
Port int `json:"port"`
User string `json:"user"`
Password string `json:"password"`
DBName string `json:"dbname"`
}
func NewMySQLDB() (*sql.DB, error) {
log.Println("coming NewMySQLDB ...")
config, err := loadMySQLConfig()
log.Println("coming NewMySQLDB config...", config.User, config.Password)
if err != nil {
log.Fatal(err)
return nil, err
}
log.Println("coming NewMySQLDB config...", config)
dbSource := fmt.Sprintf("%s:%s@tcp(%s:%d)/%s?charset=utf8", config.User, config.Password, config.Host, config.Port, config.DBName)
log.Println("coming NewMySQLDB config dbSource is ...", dbSource)
db, err := sql.Open("mysql", dbSource)
if err != nil {
log.Fatal(err)
return nil, err
}
if err := db.Ping(); err != nil {
log.Fatal(err)
return nil, err
}
return db, nil
}
func loadMySQLConfig() (*MySQLConfig, error) {
configFile, err := ioutil.ReadFile("config.json")
if err != nil {
log.Fatal("----------error-----------loadMySQLConfig err...", err)
return nil, err
}
var config MySQLConfig
err = json.Unmarshal(configFile, &config)
log.Println("loadMySQLConfig Unmarshal err...", err)
if err != nil {
log.Fatal("---------error----------------loadMySQLConfig Unmarshal err...", config)
return nil, err
}
return &config, nil
}4.创建数据库实体类 user 以及项目所需实体类ErrorResponse
user.go 的文件内容如下：
package models
type User struct {
ID uint `json:"id"`
Name string `json:"name"`
Age int `json:"age"`
}ErrorResponse.go 中的文件内容如下:
package models
type ErrorResponse struct {
Message string `json:"message"`
}5.编写user表中数据库交互的逻辑
package repositories
import (
"database/sql"
"go_test/models"
)
type UserRepository struct {
DB *sql.DB
}
func (ur *UserRepository) CreateUser(user *models.User) error {
query := "INSERT INTO users (name, age) VALUES (?, ?)"
_, err := ur.DB.Exec(query, user.Name, user.Age)
if err != nil {
return err
}
return nil
}
func (ur *UserRepository) GetUserByID(id uint) (*models.User, error) {
query := "SELECT id, name, age FROM users WHERE id = ?"
row := ur.DB.QueryRow(query, id)
user := new(models.User)
err := row.Scan(&user.ID, &user.Name, &user.Age)
if err != nil {
if err == sql.ErrNoRows {
return nil, nil // 用户不存在
}
return nil, err
}
return user, nil
}
func (ur *UserRepository) GetUsers() ([]*models.User, error) {
query := "SELECT id, name, age FROM "
rows, err := ur.DB.Query(query)
if err != nil {
return nil, err
}
defer rows.Close()
users := []*models.User{}
for rows.Next() {
user := new(models.User)
err := rows.Scan(&user.ID, &user.Name, &user.Age)
if err != nil {
return nil, err
}
users = append(users, user)
}
return users, nil
}
func (ur *UserRepository) UpdateUser(user *models.User) error {
query := "UPDATE users SET name = ?, age = ? WHERE id = ?"
_, err := ur.DB.Exec(query, user.Name, user.Age, user.ID)
if err != nil {
return err
}
return nil
}
func (ur *UserRepository) DeleteUser(id uint) error {
query := "DELETE FROM users WHERE id = ?"
_, err := ur.DB.Exec(query, id)
if err != nil {
return err
}
return nil
}6.编写处理业务层的service
package services
import (
"errors"
"go_test/models"
"go_test/repositories"
)
type UserService struct {
UserRepository *repositories.UserRepository
}
func (us *UserService) CreateUser(user *models.User) error {
if user.Name == "" {
return errors.New("Name is required")
}
if user.Age <= 0 {
return errors.New("Age should be greater than 0")
}
// ... 其他基础业务校验
return us.UserRepository.CreateUser(user)
}
func (us *UserService) GetUserByID(id uint) (*models.User, error) {
return us.UserRepository.GetUserByID(id)
}
func (us *UserService) GetUsers() ([]*models.User, error) {
return us.UserRepository.GetUsers()
}
func (us *UserService) UpdateUser(user *models.User) error {
if user.Name == "" {
return errors.New("Name is required")
}
if user.Age <= 0 {
return errors.New("Age should be greater than 0")
}
// ... 其他基础业务校验
return us.UserRepository.UpdateUser(user)
}
func (us *UserService) DeleteUser(id uint) error {
return us.UserRepository.DeleteUser(id)
}7.编写两个项目常用的util
error_handler.go
package utils
import (
"encoding/json"
"go_test/models"
_ "log"
"net/http"
)
//
//type ErrorResponse struct {
// Message string `json:"message"`
//}
func HandleError(w http.ResponseWriter, statusCode int, message string) {
errResponse := models.ErrorResponse{Message: message}
response, _ := json.Marshal(errResponse)
w.Header().Set("Content-Type", "application/json")
w.WriteHeader(statusCode)
w.Write(response)
}
func ErrorHandlerString(w http.ResponseWriter, message string) {
errResponse := models.ErrorResponse{Message: message}
response, _ := json.Marshal(errResponse)
w.Header().Set("Content-Type", "application/json")
//w.WriteHeader(statusCode)
w.Write(response)
}
func ErrorHandler(w http.ResponseWriter, err error) {
if err != nil {
w.WriteHeader(http.StatusInternalServerError)
response := models.ErrorResponse{
Message: err.Error(),
}
json.NewEncoder(w).Encode(response)
return
}
}json_utils.go
package utils
import (
"encoding/json"
"net/http"
)
func RespondJSON(w http.ResponseWriter, data interface{}, statusCode int) {
w.Header().Set("Content-Type", "application/json")
w.WriteHeader(statusCode)
json.NewEncoder(w).Encode(data)
}8.编写核心类：main.go
package main
import (
_ "database/sql"
"encoding/json"
"go_test/models"
"go_test/utils"
"log"
"net/http"
"go_test/database"
"go_test/repositories"
"go_test/services"
)
func main() {
log.Println("coming main method ...")
db, err := database.NewMySQLDB()
if err != nil {
log.Fatal(err)
}
userRepository := &repositories.UserRepository{
DB: db,
}
userService := &services.UserService{
UserRepository: userRepository,
}
http.HandleFunc("/users", func(w http.ResponseWriter, r *http.Request) {
switch r.Method {
case http.MethodGet:
users, err := userService.GetUsers()
if err != nil {
utils.ErrorHandler(w, err)
return
}
utils.RespondJSON(w, users, http.StatusOK)
case http.MethodPost:
var user models.User
err := json.NewDecoder(r.Body).Decode(&user)
if err != nil {
utils.ErrorHandler(w, err)
return
}
err = userService.CreateUser(&user)
if err != nil {
utils.ErrorHandler(w, err)
return
}
utils.RespondJSON(w, user, http.StatusCreated)
default:
w.WriteHeader(http.StatusMethodNotAllowed)
response := models.ErrorResponse{
Message: "Method not allowed",
}
json.NewEncoder(w).Encode(response)
}
})
log.Println("Server is running on port 8000")
log.Fatal(http.ListenAndServe(":8000", nil))
}9.在服务器上部署和验证
linux上传代码并进行编译项目
linux上启动项目
调用api：
到此这篇关于go项目实现mysql接入以及web api的文章就介绍到这了,更多相关go项目mysql接入以及web api内容请搜索脚本之家以前的文章或继续浏览下面的相关文章希望大家以后多多支持脚本之家！