一、初始化项目

mkdir go-app
cd go-app
go mod init app

二、设置第三方依赖包

go get github.com/go-sql-driver/mysql@v1.5.0
go get github.com/gin-gonic/gin@v1.6.3
go get github.com/gomodule/redigo/redis@v1.8.3

三、开始编码

package main

import (
	"database/sql"
	"log"

	"github.com/gin-gonic/gin"
	_ "github.com/go-sql-driver/mysql"
)

var db *sql.DB

func main() {
	databaseInit()
	defer db.Close()
	gin.SetMode(gin.ReleaseMode)
	r := gin.Default()
	r.GET("/", IndexAction)
	r.GET("/user/:name", UserAction)
	r.Run()
}

func databaseInit() {
	var err error
	db, err = sql.Open("mysql", "root:123456@tcp(127.0.0.1:3306)/wordpress")
	if err != nil {
		log.Fatalln(err)
	}
	db.SetMaxIdleConns(500)
	db.SetMaxOpenConns(500)
	err = db.Ping()
	if err != nil {
		log.Fatalln(err)
	}
}

func IndexAction(c *gin.Context) {
	c.JSON(200, gin.H{"message": "index"})
}

func UserAction(c *gin.Context) {
	var ID int
	err := db.QueryRow("SELECT ID FROM wp_users WHERE user_login = ?", c.Param("name")).Scan(&ID)
	if err == nil {
		c.String(200, "Hello %d", ID)
	} else {
		c.String(200, "Hello nobody")
	}
}

四、生成本地依赖

go mod vendor

五、运行

go run -mod=vendor main.go