Add initial model structs for CreatedAt, UpdatedAt, and DeletedAt fun…

…ctionality

lib/model/model.go

@@ -0,0 +1,40 @@
+package model
+
+import "time"
+
+// CreatedAt represents the timestamp of when an entity or object was created.
+// It is used to track the creation time of various entities.
+type CreatedAt struct {
+	CreatedAt time.Time `gorm:"column:created_at" json:"created_at"`
+}
+
+// UpdatedAt represents the timestamp when an entity was last updated.
+// It is used to keep track of the latest modification of the entity.
+type UpdatedAt struct {
+	UpdatedAt time.Time `gorm:"column:updated_at" json:"updated_at"`
+}
+
+// DeletedAt struct represents the soft delete functionality in GORM.
+// It embeds the `gorm.DeletedAt` struct, which provides the necessary fields for soft deletion.
+type DeletedAt struct {
+	Deleted   bool       `gorm:"column:deleted;index:deleted" json:"deleted"`
+	DeletedAt *time.Time `gorm:"column:deleted_at" json:"deleted_at"`
+}
+
+// IsDeleted returns true if the Deleted field of the DeletedAt object is set to true, indicating that the object has been deleted. Otherwise, it returns false.
+func (o *DeletedAt) IsDeleted() bool {
+	return o.Deleted
+}
+
+// Delete updates the `Deleted` and `DeletedAt` fields of the `DeletedAt` object.
+// If `v` is true, `Deleted` is set to `v` and `DeletedAt` is set to the current time.
+// If `v` is false, `Deleted` is set to `v` and `DeletedAt` is set to `nil`.
+func (o *DeletedAt) Delete(v bool) {
+	o.Deleted = v
+	if v {
+		var now = time.Now()
+		o.DeletedAt = &now
+	} else {
+		o.DeletedAt = nil
+	}
+}