Go language learning notes - Gorm use - table addition, deletion, modification and query | web framework gin (VIII)

Catalog

Add / modify interface

Query all interfaces that have not been logically deleted

according to ID Delete interface

Time field serialization problem processing

Interface validation

Summary

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Learning notes , Where is where .

Next to the previous article ：Go English learning notes - gorm Use - Database configuration 、 Table new | Web frame Gin（ 7、 ... and ）_ Swordsman a Liang _ALiang The blog of -CSDN Blog

The database initialization configuration has been completed , In the last article, I wrote a simple demo Interface .

This article follows the previous one , Add, delete, modify and check the table , At the same time, the time field is specially processed .

Project address ：github Address

Add / modify interface

Generally, we are in actual projects , It will merge the new interface with the update and modification interface , That is, pass parameters with ID If yes, it is modified , No ID If yes, it is new .

According to the compilation method of the project structure , stay student_service Add below AddOrUpdateStudent Method .

The method code is as follows ：

// Add or update students 
func (t StudentImpl) AddOrUpdateStudent(student *db_entity.Student) rsp.ResponseMsg {
	log.Logger.Info(" Add or update student parameters :", log.Any("Student", student))
	_db := mysql.GetDB()
	if student.Id != 0 {
		_db.Model(&student).Updates(student)
	} else {
		_db.Create(&student)
	}
	return *rsp.SuccessMsg(" Successful operation ")
}

Be careful ： In the interface test, you will find that delivery update_time Time field parsing error , In the following summary, we will talk about customizing the event structure to solve json Time field serialization problem .

Query all interfaces that have not been logically deleted

stay student_service Add below SelectAll Method , Yes del_flag by 0 Query by users .

The method code is as follows ：

// Query all students 
func (t StudentImpl) SelectAll() rsp.ResponseMsg {
	log.Logger.Info(" Query all students ")
	_db := mysql.GetDB()
	var _result []db_entity.Student
	_db.Where("del_flag = ?", 0).Find(&_result)
	return *rsp.SuccessMsg(_result)
}

according to ID Delete interface

stay student_service Add new basis ID Delete data interface .

The method code is as follows ：

// according to id Delete students 
func (t StudentImpl) DeleteById(id int32) rsp.ResponseMsg {
	log.Logger.Info(" according to id Delete students ")
	_db := mysql.GetDB()
	_db.Delete(&db_entity.Student{}, id)
	return *rsp.SuccessMsg(" Delete successful ")
}

Time field serialization problem processing

because json Can't serialize directly time.Time type , There are many solutions online , I mainly use the method of rewriting the serialization method of user-defined time types to solve .

stay constants Under the table of contents , establish common.go file .

common.go The code is as follows ：

package constants

import (
	"database/sql/driver"
	"fmt"
	"time"
)

type HTime struct {
	time.Time
}

var (
	formatTime = "2006-01-02 15:04:05"
)

func (t HTime) MarshalJSON() ([]byte, error) {
	formatted := fmt.Sprintf("\"%s\"", t.Format(formatTime))
	return []byte(formatted), nil
}

func (t *HTime) UnmarshalJSON(data []byte) (err error) {
	now, err := time.ParseInLocation(`"`+formatTime+`"`, string(data), time.Local)
	*t = HTime{Time: now}
	return
}

func (t HTime) Value() (driver.Value, error) {
	var zeroTime time.Time
	if t.Time.UnixNano() == zeroTime.UnixNano() {
		return nil, nil
	}
	return t.Time, nil
}

func (t *HTime) Scan(v interface{}) error {
	value, ok := v.(time.Time)
	if ok {
		*t = HTime{Time: value}
		return nil
	}
	return fmt.Errorf("can not convert %v to timestamp", v)
}

Be careful ：

1、 Redefinition HTime Structure , Adjust the serialization method .

2、Student In the structure UpdateTime Adjust the field data type to HTime, Adjusted as follows .

type Student struct {
	Id         int32           `json:"id" gorm:"column:id;primary_key;AUTO_INCREMENT;comment:'id'"`
	Name       string          `json:"name" gorm:"column:name;type:varchar(255);comment:' name '"`
	Age        int64           `json:"age" gorm:"column:age;comment:' Age '"`
	Content    string          `json:"content" gorm:"column:content;type:varchar(255);comment:' describe '"`
	UpdateTime constants.HTime `json:"update_time" time_format:"unix" gorm:"column:update_time"`
	DelFlag    int64           `json:"del_flag" gorm:"column:del_flag;comment:' Delete logo '"`
}

Interface validation

controller Add interface code in layer , as follows ：

// Add or modify a student information 
func (s StudentController) AddOrUpdateStudent(context *gin.Context) {
	var addOrUpdateStudent db_entity.Student
	log.Logger.Info("AddOrUpdateStudent Interface ")
	if err := context.ShouldBindJSON(&addOrUpdateStudent); err != nil {
		log.Logger.Panic(" Parameter exception ")
	}

	if _, err := json.Marshal(addOrUpdateStudent); err != nil {
		log.Logger.Panic(" Parameter parsing exception ")
	}
	_rsp := services.StudentServ.AddOrUpdateStudent(&addOrUpdateStudent)
	context.JSON(http.StatusOK, _rsp)
}

// Query all students 
func (s StudentController) SelectAll(context *gin.Context) {
	log.Logger.Info("SelectAll Interface ")
	_rsp := services.StudentServ.SelectAll()
	context.JSON(http.StatusOK, _rsp)
}

// according to id Delete students 
func (s StudentController) DeleteById(context *gin.Context) {
	log.Logger.Info("DeleteById Interface ")
	_id := context.Query("id")
	_a, _ := strconv.ParseInt(_id, 10, 64)
	_rsp := services.StudentServ.DeleteById(int32(_a))
	context.JSON(http.StatusOK, _rsp)
}

router Add routing path , as follows ：

func StudentRouter(r *gin.Engine) {
	r.POST("/student/addOne", controllers.StudentCtrl.StudentAddOne)
	r.POST("/student/addOrUpdateStudent", controllers.StudentCtrl.AddOrUpdateStudent)
	r.GET("/student/selectAll", controllers.StudentCtrl.SelectAll)
	r.DELETE("/student/deleteById", controllers.StudentCtrl.DeleteById)
}

Verify them separately 3 Interface .

Add / modify interface

Query interface

Delete interface

Summary

To be honest, I'm a little busy recently , Take time to study when you are busy . Continue to operate some complex query operations later .

Reference link ：gorm time.Time Use hook function to solve deserialization problem _qq_26372385 The blog of -CSDN Blog