Go language learning notes - Gorm use - Gorm processing errors | web framework gin (10)

Learning notes , Where is where .

Next to the previous article ：Go English learning notes - gorm Use - Native sql、 Named parameters 、Rows、ToSQL | Web frame Gin（ Nine ）_ Swordsman a Liang _ALiang The blog of -CSDN Blog

at present gorm Have a basic understanding of some database operations .

This article mainly tests gorm Exception handling method of .

Project address ：github Address

You can have a look first gorm Defined exception , The code is as follows ：

var (
	// ErrRecordNotFound record not found error
	ErrRecordNotFound = logger.ErrRecordNotFound
	// ErrInvalidTransaction invalid transaction when you are trying to `Commit` or `Rollback`
	ErrInvalidTransaction = errors.New("invalid transaction")
	// ErrNotImplemented not implemented
	ErrNotImplemented = errors.New("not implemented")
	// ErrMissingWhereClause missing where clause
	ErrMissingWhereClause = errors.New("WHERE conditions required")
	// ErrUnsupportedRelation unsupported relations
	ErrUnsupportedRelation = errors.New("unsupported relations")
	// ErrPrimaryKeyRequired primary keys required
	ErrPrimaryKeyRequired = errors.New("primary key required")
	// ErrModelValueRequired model value required
	ErrModelValueRequired = errors.New("model value required")
	// ErrInvalidData unsupported data
	ErrInvalidData = errors.New("unsupported data")
	// ErrUnsupportedDriver unsupported driver
	ErrUnsupportedDriver = errors.New("unsupported driver")
	// ErrRegistered registered
	ErrRegistered = errors.New("registered")
	// ErrInvalidField invalid field
	ErrInvalidField = errors.New("invalid field")
	// ErrEmptySlice empty slice found
	ErrEmptySlice = errors.New("empty slice found")
	// ErrDryRunModeUnsupported dry run mode unsupported
	ErrDryRunModeUnsupported = errors.New("dry run mode unsupported")
	// ErrInvalidDB invalid db
	ErrInvalidDB = errors.New("invalid db")
	// ErrInvalidValue invalid value
	ErrInvalidValue = errors.New("invalid value, should be pointer to struct or slice")
	// ErrInvalidValueOfLength invalid values do not match length
	ErrInvalidValueOfLength = errors.New("invalid association values, length doesn't match")
	// ErrPreloadNotAllowed preload is not allowed when count is used
	ErrPreloadNotAllowed = errors.New("preload is not allowed when count is used")
)

Write an interface to test the exception .

stay student_service Add below TestError Method .

The method code is as follows ：

// test gorm abnormal 
func (t StudentImpl) TestError() rsp.ResponseMsg {
	log.Logger.Info(" test gorm abnormal ")
	_db := mysql.GetDB()
	var _student db_entity.Student
	if _err := _db.Where("del_flag = 1").First(&_student).Error; _err != nil {
		if errors.Is(_err, gorm.ErrRecordNotFound) {
			fmt.Println("error is ErrRecordNotFound")
		}
		log.Logger.Panic("error -> ", log.Any("error", _err))
	}
	log.Logger.Debug("student -> ", log.Any("student", _student))
	return *rsp.SuccessMsg(" Test success ")
}

If sql Can't get record, It will be reported ErrRecordNotFound abnormal .

controller Add interface code in layer , as follows ：

// test gorm abnormal 
func (s StudentController) TestError(context *gin.Context) {
	log.Logger.Info(" test gorm Exception interface ")
	_rsp := services.StudentServ.TestError()
	context.JSON(http.StatusOK, _rsp)
}

Verify the printout after the interface is executed .

It can be seen that the exception response message captured globally .

Summary

In project development , Exception handling is quite necessary .

A little busy recently , Also have some understanding , Sometimes you need to release the pressure , But we need a reasonable and effective way . Sometimes you need to share the pressure with others , It's not always necessary to carry all .