gorm/soft_delete.go

131 lines
3.3 KiB
Go

package gorm
import (
"database/sql"
"database/sql/driver"
"encoding/json"
"reflect"
"gorm.io/gorm/clause"
"gorm.io/gorm/schema"
)
type DeletedAt sql.NullTime
// Scan implements the Scanner interface.
func (n *DeletedAt) Scan(value interface{}) error {
return (*sql.NullTime)(n).Scan(value)
}
// Value implements the driver Valuer interface.
func (n DeletedAt) Value() (driver.Value, error) {
if !n.Valid {
return nil, nil
}
return n.Time, nil
}
func (n DeletedAt) MarshalJSON() ([]byte, error) {
if n.Valid {
return json.Marshal(n.Time)
}
return json.Marshal(nil)
}
func (n *DeletedAt) UnmarshalJSON(b []byte) error {
if string(b) == "null" {
n.Valid = false
return nil
}
err := json.Unmarshal(b, &n.Time)
if err == nil {
n.Valid = true
}
return err
}
func (DeletedAt) QueryClauses(f *schema.Field) []clause.Interface {
return []clause.Interface{SoftDeleteQueryClause{Field: f}}
}
type SoftDeleteQueryClause struct {
Field *schema.Field
}
func (sd SoftDeleteQueryClause) Name() string {
return ""
}
func (sd SoftDeleteQueryClause) Build(clause.Builder) {
}
func (sd SoftDeleteQueryClause) MergeClause(*clause.Clause) {
}
func (sd SoftDeleteQueryClause) ModifyStatement(stmt *Statement) {
if _, ok := stmt.Clauses["soft_delete_enabled"]; !ok {
if c, ok := stmt.Clauses["WHERE"]; ok {
if where, ok := c.Expression.(clause.Where); ok && len(where.Exprs) > 1 {
for _, expr := range where.Exprs {
if orCond, ok := expr.(clause.OrConditions); ok && len(orCond.Exprs) == 1 {
where.Exprs = []clause.Expression{clause.And(where.Exprs...)}
c.Expression = where
stmt.Clauses["WHERE"] = c
break
}
}
}
}
stmt.AddClause(clause.Where{Exprs: []clause.Expression{
clause.Eq{Column: clause.Column{Table: clause.CurrentTable, Name: sd.Field.DBName}, Value: nil},
}})
stmt.Clauses["soft_delete_enabled"] = clause.Clause{}
}
}
func (DeletedAt) DeleteClauses(f *schema.Field) []clause.Interface {
return []clause.Interface{SoftDeleteDeleteClause{Field: f}}
}
type SoftDeleteDeleteClause struct {
Field *schema.Field
}
func (sd SoftDeleteDeleteClause) Name() string {
return ""
}
func (sd SoftDeleteDeleteClause) Build(clause.Builder) {
}
func (sd SoftDeleteDeleteClause) MergeClause(*clause.Clause) {
}
func (sd SoftDeleteDeleteClause) ModifyStatement(stmt *Statement) {
if stmt.SQL.String() == "" {
stmt.AddClause(clause.Set{{Column: clause.Column{Name: sd.Field.DBName}, Value: stmt.DB.NowFunc()}})
if stmt.Schema != nil {
_, queryValues := schema.GetIdentityFieldValuesMap(stmt.ReflectValue, stmt.Schema.PrimaryFields)
column, values := schema.ToQueryValues(stmt.Table, stmt.Schema.PrimaryFieldDBNames, queryValues)
if len(values) > 0 {
stmt.AddClause(clause.Where{Exprs: []clause.Expression{clause.IN{Column: column, Values: values}}})
}
if stmt.ReflectValue.CanAddr() && stmt.Dest != stmt.Model && stmt.Model != nil {
_, queryValues = schema.GetIdentityFieldValuesMap(reflect.ValueOf(stmt.Model), stmt.Schema.PrimaryFields)
column, values = schema.ToQueryValues(stmt.Table, stmt.Schema.PrimaryFieldDBNames, queryValues)
if len(values) > 0 {
stmt.AddClause(clause.Where{Exprs: []clause.Expression{clause.IN{Column: column, Values: values}}})
}
}
}
stmt.AddClauseIfNotExists(clause.Update{})
stmt.Build("UPDATE", "SET", "WHERE")
}
}