121 lines
2.7 KiB
Go
121 lines
2.7 KiB
Go
package zero
|
|
|
|
import (
|
|
"database/sql"
|
|
"encoding/json"
|
|
"fmt"
|
|
"reflect"
|
|
"strconv"
|
|
)
|
|
|
|
// Int is a nullable int64.
|
|
// JSON marshals to zero if null.
|
|
// Considered null to SQL if zero.
|
|
type Int struct {
|
|
sql.NullInt64
|
|
}
|
|
|
|
// NewInt creates a new Int
|
|
func NewInt(i int64, valid bool) Int {
|
|
return Int{
|
|
NullInt64: sql.NullInt64{
|
|
Int64: i,
|
|
Valid: valid,
|
|
},
|
|
}
|
|
}
|
|
|
|
// IntFrom creates a new Int that will be null if zero.
|
|
func IntFrom(i int64) Int {
|
|
return NewInt(i, i != 0)
|
|
}
|
|
|
|
// IntFromPtr creates a new Int that be null if i is nil.
|
|
func IntFromPtr(i *int64) Int {
|
|
if i == nil {
|
|
return NewInt(0, false)
|
|
}
|
|
n := NewInt(*i, true)
|
|
return n
|
|
}
|
|
|
|
// UnmarshalJSON implements json.Unmarshaler.
|
|
// It supports number and null input.
|
|
// 0 will be considered a null Int.
|
|
// It also supports unmarshalling a sql.NullInt64.
|
|
func (i *Int) UnmarshalJSON(data []byte) error {
|
|
var err error
|
|
var v interface{}
|
|
if err = json.Unmarshal(data, &v); err != nil {
|
|
return err
|
|
}
|
|
switch v.(type) {
|
|
case float64:
|
|
// Unmarshal again, directly to int64, to avoid intermediate float64
|
|
err = json.Unmarshal(data, &i.Int64)
|
|
case map[string]interface{}:
|
|
err = json.Unmarshal(data, &i.NullInt64)
|
|
case nil:
|
|
i.Valid = false
|
|
return nil
|
|
default:
|
|
err = fmt.Errorf("json: cannot unmarshal %v into Go value of type zero.Int", reflect.TypeOf(v).Name())
|
|
}
|
|
i.Valid = (err == nil) && (i.Int64 != 0)
|
|
return err
|
|
}
|
|
|
|
// UnmarshalText implements encoding.TextUnmarshaler.
|
|
// It will unmarshal to a null Int if the input is a blank, zero, or not an integer.
|
|
// It will return an error if the input is not an integer, blank, or "null".
|
|
func (i *Int) UnmarshalText(text []byte) error {
|
|
str := string(text)
|
|
if str == "" || str == "null" {
|
|
i.Valid = false
|
|
return nil
|
|
}
|
|
var err error
|
|
i.Int64, err = strconv.ParseInt(string(text), 10, 64)
|
|
i.Valid = (err == nil) && (i.Int64 != 0)
|
|
return err
|
|
}
|
|
|
|
// MarshalJSON implements json.Marshaler.
|
|
// It will encode 0 if this Int is null.
|
|
func (i Int) MarshalJSON() ([]byte, error) {
|
|
n := i.Int64
|
|
if !i.Valid {
|
|
n = 0
|
|
}
|
|
return []byte(strconv.FormatInt(n, 10)), nil
|
|
}
|
|
|
|
// MarshalText implements encoding.TextMarshaler.
|
|
// It will encode a zero if this Int is null.
|
|
func (i Int) MarshalText() ([]byte, error) {
|
|
n := i.Int64
|
|
if !i.Valid {
|
|
n = 0
|
|
}
|
|
return []byte(strconv.FormatInt(n, 10)), nil
|
|
}
|
|
|
|
// SetValid changes this Int's value and also sets it to be non-null.
|
|
func (i *Int) SetValid(n int64) {
|
|
i.Int64 = 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() *int64 {
|
|
if !i.Valid {
|
|
return nil
|
|
}
|
|
return &i.Int64
|
|
}
|
|
|
|
// IsZero returns true for null or zero Ints, for future omitempty support (Go 1.4?)
|
|
func (i Int) IsZero() bool {
|
|
return !i.Valid || i.Int64 == 0
|
|
}
|