[ADD]添加callback回调

models/employee.go

@@ -1,19 +1,12 @@
 package models
 
-import (
-	"github.com/jinzhu/gorm"
-	"time"
-)
-
 type Employee struct {
-	ID         int    `gorm:"primary_key" json:"id"`
+	Model
 	Username   string `json:"username"`
 	Password   string `json:"password"`
 	Department string `json:"department"`
 	Position   string `json:"position"`
 	State      int    `json:"state"`
-	CreatedOn  int    `json:"created_on"`
-	ModifiedOn int    `json:"modified_on"`
 }
 
 func CheckEmployee(username, password string) bool {
@@ -77,15 +70,3 @@ func AddArticle(data map[string]interface{}) bool {
 	})
 	return true
 }
-
-func (employee *Employee) BeforeCreate(scope *gorm.Scope) error {
-	scope.SetColumn("CreateOn", time.Now().Unix())
-
-	return  nil
-}
-
-func (employee *Employee) BeforeUpdate(scope *gorm.Scope) error {
-	scope.SetColumn("ModifiedOn", time.Now().Unix())
-
-	return nil
-}

models/models.go

@@ -6,6 +6,7 @@ import (
 	"github.com/jinzhu/gorm"
 	_ "github.com/jinzhu/gorm/dialects/postgres"
 	"log"
+	"time"
 )
 
 var db *gorm.DB
@@ -14,11 +15,12 @@ type Model struct {
 	ID         int `gorm:"primary_key" json:"id"`
 	CreatedOn  int `json:"created_on"`
 	ModifiedOn int `json:"modified_on"`
+	DeleteOn   int `json:"deleted_on"`
 }
 
-func init()  {
+func init() {
 	var (
-		err error
+		err                                                     error
 		dbType, dbName, user, password, host, port, tablePrefix string
 	)
 
@@ -55,8 +57,66 @@ func init()  {
 	db.LogMode(true)
 	db.DB().SetMaxIdleConns(10)
 	db.DB().SetMaxOpenConns(100)
+
+	// 注册Callbacks
+	db.Callback().Create().Replace("gorm:update_time_stamp", updateTimeStampForCreateCallback)
+	db.Callback().Update().Replace("gorm:update_time_stamp", updateTimeStampForUpdateCallBack)
+	db.Callback().Delete().Replace("gorm:delete", deleteCallback)
 }
 
-func CloseDB()  {
+func CloseDB() {
 	defer db.Close()
 }
+
+func updateTimeStampForCreateCallback(scope *gorm.Scope) {
+	if !scope.HasError() {
+		nowTime := time.Now().Unix()
+		if createTimeField, ok := scope.FieldByName("CreatedOn"); ok {
+			if createTimeField.IsBlank {
+				createTimeField.Set(nowTime)
+			}
+		}
+
+		if modifyTimeField, ok := scope.FieldByName("ModifiedOn"); ok {
+			if modifyTimeField.IsBlank {
+				modifyTimeField.Set(nowTime)
+			}
+		}
+	}
+}
+
+func updateTimeStampForUpdateCallBack(scope *gorm.Scope) {
+	if _, ok := scope.Get("gorm:update_column"); !ok {
+		scope.SetColumn("ModifiedOn", time.Now().Unix())
+	}
+}
+
+func deleteCallback(scope *gorm.Scope) {
+	if !scope.HasError() {
+		var extraOption string
+		if str, ok := scope.Get("gorm:delete_option"); ok {
+			extraOption = fmt.Sprint(str)
+		}
+
+		deleteOnField, hasDeleteOnField := scope.FieldByName("DeleteOn")
+
+		if !scope.Search.Unscoped && hasDeleteOnField {
+			scope.Raw(fmt.Sprintf(
+				"update %v SET %v=%v%v%v",
+				scope.QuotedTableName(),
+				scope.Quote(deleteOnField.DBName),
+				scope.AddToVars(time.Now().Unix()),
+				addExtraSpaceIfExist(scope.CombinedConditionSql()),
+				addExtraSpaceIfExist(extraOption),
+			)).Exec()
+		}
+	}
+}
+
+func addExtraSpaceIfExist(str string) string {
+	if str != "" {
+		return  " " + str
+	}
+
+	return ""
+}