//main.gopackage mainimport (    "TestGoProject/src/Mappings"    "TestGoProject/src/Models"    _ "github.com/gin-gonic/gin"    "github.com/jinzhu/gorm"    _ "github.com/jinzhu/gorm/dialects/mysql"    _ "net/http")var db *gorm.DBfunc main()  {    initDb()    Mappings.InitializeRoutes()}func initDb() {    var err error    db, err = gorm.Open("mysql", "root:helloworld@/testapp2?charset=utf8&parseTime=True&loc=Local")    if err != nil {        panic("failed to connect database")    }    db.AutoMigrate(&Models.BookModel{})}//router.gopackage Mappingsimport (    "TestGoProject/src/Controllers"    "github.com/gin-gonic/gin")func InitializeRoutes()  {    router := gin.Default()    router.GET("/", Controllers.Index)    router.POST("/createBook", Controllers.Create)    _ = router.Run()}//BookController.gopackage Controllersimport (    "TestGoProject/src/Models"    "github.com/gin-gonic/gin"    "github.com/jinzhu/gorm"    _ "github.com/jinzhu/gorm/dialects/mysql"    "net/http")var db = gorm.DB{}func Index(c *gin.Context)  {    c.JSON(http.StatusOK, gin.H{"status": http.StatusOK, "message": "Im here!"})}func Create(c *gin.Context)  {    book := Models.BookModel{        Title: c.PostForm("title"),        Author: c.PostForm("author"),    }    db.Create(&book)    c.JSON(http.StatusCreated, gin.H{"status": http.StatusCreated, "message": "Book created successfully!", "bookId": book.ID})}//bookModel.gopackage Modelsimport "github.com/jinzhu/gorm"type BookModel struct {    gorm.Model    Title string `json:"title"`    Author string `json:"author"`}因此，當(dāng)我從 Postman 發(fā)送 POST 請(qǐng)求時(shí)，收到這樣的錯(cuò)誤嘗試解決了很多方法，但沒(méi)有奏效。任何幫助都會(huì)很棒。TIA2020/05/25 10:54:50 [Recovery] 2020/05/25 - 10:54:50 panic recovered:POST /createBook HTTP/1.1Host: localhost:8080Accept: */*Accept-Encoding: gzip, deflate, brCache-Control: no-cacheConnection: keep-aliveContent-Length: 48Content-Type: application/jsonUser-Agent: PostmanRuntime/7.25.0