storj/internal/dbutil/nulltime.go

76 lines
1.6 KiB
Go

// Copyright (C) 2019 Storj Labs, Inc.
// See LICENSE for copying information.
package dbutil
import (
"database/sql/driver"
"time"
"github.com/zeebo/errs"
)
const (
sqliteTimeLayout = "2006-01-02 15:04:05-07:00"
sqliteTimeLayoutNoTimeZone = "2006-01-02 15:04:05"
)
// ErrNullTime defines error class for NullTime.
var ErrNullTime = errs.Class("null time error")
// NullTime time helps convert nil to time.Time.
type NullTime struct {
time.Time
Valid bool
}
// Scan implements the Scanner interface.
func (nt *NullTime) Scan(value interface{}) error {
if value == nil {
return nil
}
// check if it's time.Time which is what postgres returns
// for lagged time values
if nt.Time, nt.Valid = value.(time.Time); nt.Valid {
return nil
}
// try to parse time from bytes which is what sqlite returns
date, ok := value.([]byte)
if !ok {
return ErrNullTime.New("sql null time: scan received unsupported value type")
}
times, err := parseSqliteTimeString(string(date))
if err != nil {
return ErrNullTime.Wrap(err)
}
nt.Time, nt.Valid = times, true
return nil
}
// Value implements the driver Valuer interface.
func (nt NullTime) Value() (driver.Value, error) {
if !nt.Valid {
return nil, nil
}
return nt.Time, nil
}
// parseSqliteTimeString parses sqlite times string.
// It tries to process value as string with timezone first,
// then fallback to parsing as string without timezone.
func parseSqliteTimeString(val string) (time.Time, error) {
var times time.Time
var err error
times, err = time.Parse(sqliteTimeLayout, val)
if err == nil {
return times, nil
}
return time.Parse(sqliteTimeLayoutNoTimeZone, val)
}