lbry.go/extras/null/int.go

124 lines
2.3 KiB
Go

package null
import (
"bytes"
"database/sql/driver"
"encoding/json"
"strconv"
"gopkg.in/nullbio/null.v6/convert"
)
// Int is an nullable int.
type Int struct {
Int int
Valid bool
}
// NewInt creates a new Int
func NewInt(i int, valid bool) Int {
return Int{
Int: i,
Valid: valid,
}
}
// IntFrom creates a new Int that will always be valid.
func IntFrom(i int) Int {
return NewInt(i, true)
}
// IntFromPtr creates a new Int that be null if i is nil.
func IntFromPtr(i *int) Int {
if i == nil {
return NewInt(0, false)
}
return NewInt(*i, true)
}
// UnmarshalJSON implements json.Unmarshaler.
func (i *Int) UnmarshalJSON(data []byte) error {
if bytes.Equal(data, NullBytes) {
i.Valid = false
i.Int = 0
return nil
}
var x int64
if err := json.Unmarshal(data, &x); err != nil {
return err
}
i.Int = int(x)
i.Valid = true
return nil
}
// UnmarshalText implements encoding.TextUnmarshaler.
func (i *Int) UnmarshalText(text []byte) error {
if text == nil || len(text) == 0 {
i.Valid = false
return nil
}
var err error
res, err := strconv.ParseInt(string(text), 10, 0)
i.Valid = err == nil
if i.Valid {
i.Int = int(res)
}
return err
}
// MarshalJSON implements json.Marshaler.
func (i Int) MarshalJSON() ([]byte, error) {
if !i.Valid {
return NullBytes, nil
}
return []byte(strconv.FormatInt(int64(i.Int), 10)), nil
}
// MarshalText implements encoding.TextMarshaler.
func (i Int) MarshalText() ([]byte, error) {
if !i.Valid {
return []byte{}, nil
}
return []byte(strconv.FormatInt(int64(i.Int), 10)), nil
}
// SetValid changes this Int's value and also sets it to be non-null.
func (i *Int) SetValid(n int) {
i.Int = n
i.Valid = true
}
// Ptr returns a pointer to this Int's value, or a nil pointer if this Int is null.
func (i Int) Ptr() *int {
if !i.Valid {
return nil
}
return &i.Int
}
// IsNull returns true for invalid Ints, for future omitempty support (Go 1.4?)
func (i Int) IsNull() bool {
return !i.Valid
}
// Scan implements the Scanner interface.
func (i *Int) Scan(value interface{}) error {
if value == nil {
i.Int, i.Valid = 0, false
return nil
}
i.Valid = true
return convert.ConvertAssign(&i.Int, value)
}
// Value implements the driver Valuer interface.
func (i Int) Value() (driver.Value, error) {
if !i.Valid {
return nil, nil
}
return int64(i.Int), nil
}