pgx/pgtype/aclitem.go

114 lines
2.4 KiB
Go

package pgtype
import (
"fmt"
"io"
"reflect"
)
// Aclitem is used for PostgreSQL's aclitem data type. A sample aclitem
// might look like this:
//
// postgres=arwdDxt/postgres
//
// Note, however, that because the user/role name part of an aclitem is
// an identifier, it follows all the usual formatting rules for SQL
// identifiers: if it contains spaces and other special characters,
// it should appear in double-quotes:
//
// postgres=arwdDxt/"role with spaces"
//
type Aclitem struct {
String string
Status Status
}
func (dst *Aclitem) Set(src interface{}) error {
switch value := src.(type) {
case string:
*dst = Aclitem{String: value, Status: Present}
case *string:
if value == nil {
*dst = Aclitem{Status: Null}
} else {
*dst = Aclitem{String: *value, Status: Present}
}
default:
if originalSrc, ok := underlyingStringType(src); ok {
return dst.Set(originalSrc)
}
return fmt.Errorf("cannot convert %v to Aclitem", value)
}
return nil
}
func (dst *Aclitem) Get() interface{} {
switch dst.Status {
case Present:
return dst.String
case Null:
return nil
default:
return dst.Status
}
}
func (src *Aclitem) AssignTo(dst interface{}) error {
switch v := dst.(type) {
case *string:
if src.Status != Present {
return fmt.Errorf("cannot assign %v to %T", src, dst)
}
*v = src.String
default:
if v := reflect.ValueOf(dst); v.Kind() == reflect.Ptr {
el := v.Elem()
switch el.Kind() {
// if dst is a pointer to pointer, strip the pointer and try again
case reflect.Ptr:
if src.Status == Null {
el.Set(reflect.Zero(el.Type()))
return nil
}
if el.IsNil() {
// allocate destination
el.Set(reflect.New(el.Type().Elem()))
}
return src.AssignTo(el.Interface())
case reflect.String:
if src.Status != Present {
return fmt.Errorf("cannot assign %v to %T", src, dst)
}
el.SetString(src.String)
return nil
}
}
return fmt.Errorf("cannot decode %v into %T", src, dst)
}
return nil
}
func (dst *Aclitem) DecodeText(src []byte) error {
if src == nil {
*dst = Aclitem{Status: Null}
return nil
}
*dst = Aclitem{String: string(src), Status: Present}
return nil
}
func (src Aclitem) EncodeText(w io.Writer) (bool, error) {
switch src.Status {
case Null:
return true, nil
case Undefined:
return false, errUndefined
}
_, err := io.WriteString(w, src.String)
return false, err
}