gin 一对多模型保存代码-Go服务器开发

以下是使用gin框架保存一对多模型的示例代码：

package main
import (
    "github.com/gin-gonic/gin"
    "gorm.io/driver/mysql"
    "gorm.io/gorm"
)
type User struct {
    gorm.Model
    Name     string
    Email    string
    Articles []Article // 一个用户可以有多篇文章
}
type Article struct {
    gorm.Model
    Title     string
    Content   string
    UserID    uint // 外键，指向User表中的ID字段
}
func main() {
    dsn := "username:password@tcp(localhost:3306)/database?charset=utf8mb4&parseTime=True&loc=Local"
    db, err := gorm.Open(mysql.Open(dsn), &gorm.Config{})
    
	if err != nil {
        panic("failed to connect database")
	}
	
	db.AutoMigrate(&User{}, &Article{})
	r := gin.Default()
	r.POST("/users", func(c *gin.Context) {
		var user User
		
		err := c.ShouldBindJSON(&user)
		if err != nil {
			c.JSON(400, gin.H{"error": err.Error()})
			return
		}
		
		result := db.Create(&user)
		if result.Error != nil {
			c.JSON(500, gin.H{"error": result.Error.Error()})
			return
		}
		
		c.JSON(200, user)
	})
	r.POST("/articles", func(c *gin.Context) {
        var article Article
        
        err := c.ShouldBindJSON(&article)
        if err != nil {
            c.JSON(400, gin.H{"error": err.Error()})
            return
        }
        
        var user User
        
        result := db.First(&user, article.UserID)
        if result.Error != nil {
            c.JSON(500, gin.H{"error": result.Error.Error()})
            return
        }
        
        article.UserID = user.ID
        
        result = db.Create(&article)
        if result.Error != nil {
            c.JSON(500, gin.H{"error": result.Error.Error()})
            return
        }
        
        c.JSON(200, article)
    })
	r.GET("/users/:id", func(c *gin.Context) {
		var user User
		
		result := db.Preload("Articles").First(&user, c.Param("id"))
		if result.Error != nil {
			c.JSON(500, gin.H{"error": result.Error.Error()})
			return
		}
		
		c.JSON(200, user)
	})
	r.Run()
}