gitea/vendor/xorm.io/xorm/convert/conversion.go
2021-09-15 23:27:46 +08:00

391 lines
7.5 KiB
Go
Vendored

// Copyright 2017 The Xorm Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package convert
import (
"database/sql"
"database/sql/driver"
"encoding/json"
"errors"
"fmt"
"math/big"
"reflect"
"strconv"
"time"
)
// Conversion is an interface. A type implements Conversion will according
// the custom method to fill into database and retrieve from database.
type Conversion interface {
FromDB([]byte) error
ToDB() ([]byte, error)
}
// ErrNilPtr represents an error
var ErrNilPtr = errors.New("destination pointer is nil") // embedded in descriptive error
func strconvErr(err error) error {
if ne, ok := err.(*strconv.NumError); ok {
return ne.Err
}
return err
}
func cloneBytes(b []byte) []byte {
if b == nil {
return nil
}
c := make([]byte, len(b))
copy(c, b)
return c
}
// Assign copies to dest the value in src, converting it if possible.
// An error is returned if the copy would result in loss of information.
// dest should be a pointer type.
func Assign(dest, src interface{}, originalLocation *time.Location, convertedLocation *time.Location) error {
// Common cases, without reflect.
switch s := src.(type) {
case *interface{}:
return Assign(dest, *s, originalLocation, convertedLocation)
case string:
switch d := dest.(type) {
case *string:
if d == nil {
return ErrNilPtr
}
*d = s
return nil
case *[]byte:
if d == nil {
return ErrNilPtr
}
*d = []byte(s)
return nil
}
case []byte:
switch d := dest.(type) {
case *string:
if d == nil {
return ErrNilPtr
}
*d = string(s)
return nil
case *interface{}:
if d == nil {
return ErrNilPtr
}
*d = cloneBytes(s)
return nil
case *[]byte:
if d == nil {
return ErrNilPtr
}
*d = cloneBytes(s)
return nil
}
case time.Time:
switch d := dest.(type) {
case *string:
*d = s.Format(time.RFC3339Nano)
return nil
case *[]byte:
if d == nil {
return ErrNilPtr
}
*d = []byte(s.Format(time.RFC3339Nano))
return nil
}
case nil:
switch d := dest.(type) {
case *interface{}:
if d == nil {
return ErrNilPtr
}
*d = nil
return nil
case *[]byte:
if d == nil {
return ErrNilPtr
}
*d = nil
return nil
}
case *sql.NullString:
switch d := dest.(type) {
case *int:
if s.Valid {
*d, _ = strconv.Atoi(s.String)
}
return nil
case *int64:
if s.Valid {
*d, _ = strconv.ParseInt(s.String, 10, 64)
}
return nil
case *string:
if s.Valid {
*d = s.String
}
return nil
case *time.Time:
if s.Valid {
var err error
dt, err := String2Time(s.String, originalLocation, convertedLocation)
if err != nil {
return err
}
*d = *dt
}
return nil
case *sql.NullTime:
if s.Valid {
var err error
dt, err := String2Time(s.String, originalLocation, convertedLocation)
if err != nil {
return err
}
d.Valid = true
d.Time = *dt
}
return nil
case *big.Float:
if s.Valid {
if d == nil {
d = big.NewFloat(0)
}
d.SetString(s.String)
}
return nil
}
case *sql.NullInt32:
switch d := dest.(type) {
case *int:
if s.Valid {
*d = int(s.Int32)
}
return nil
case *int8:
if s.Valid {
*d = int8(s.Int32)
}
return nil
case *int16:
if s.Valid {
*d = int16(s.Int32)
}
return nil
case *int32:
if s.Valid {
*d = s.Int32
}
return nil
case *int64:
if s.Valid {
*d = int64(s.Int32)
}
return nil
}
case *sql.NullInt64:
switch d := dest.(type) {
case *int:
if s.Valid {
*d = int(s.Int64)
}
return nil
case *int8:
if s.Valid {
*d = int8(s.Int64)
}
return nil
case *int16:
if s.Valid {
*d = int16(s.Int64)
}
return nil
case *int32:
if s.Valid {
*d = int32(s.Int64)
}
return nil
case *int64:
if s.Valid {
*d = s.Int64
}
return nil
}
case *sql.NullFloat64:
switch d := dest.(type) {
case *int:
if s.Valid {
*d = int(s.Float64)
}
return nil
case *float64:
if s.Valid {
*d = s.Float64
}
return nil
}
case *sql.NullBool:
switch d := dest.(type) {
case *bool:
if s.Valid {
*d = s.Bool
}
return nil
}
case *sql.NullTime:
switch d := dest.(type) {
case *time.Time:
if s.Valid {
*d = s.Time
}
return nil
case *string:
if s.Valid {
*d = s.Time.In(convertedLocation).Format("2006-01-02 15:04:05")
}
return nil
}
case *NullUint32:
switch d := dest.(type) {
case *uint8:
if s.Valid {
*d = uint8(s.Uint32)
}
return nil
case *uint16:
if s.Valid {
*d = uint16(s.Uint32)
}
return nil
case *uint:
if s.Valid {
*d = uint(s.Uint32)
}
return nil
}
case *NullUint64:
switch d := dest.(type) {
case *uint64:
if s.Valid {
*d = s.Uint64
}
return nil
}
case *sql.RawBytes:
switch d := dest.(type) {
case Conversion:
return d.FromDB(*s)
}
}
var sv reflect.Value
switch d := dest.(type) {
case *string:
sv = reflect.ValueOf(src)
switch sv.Kind() {
case reflect.Bool,
reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64,
reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64,
reflect.Float32, reflect.Float64:
*d = AsString(src)
return nil
}
case *[]byte:
if b, ok := AsBytes(src); ok {
*d = b
return nil
}
case *bool:
bv, err := driver.Bool.ConvertValue(src)
if err == nil {
*d = bv.(bool)
}
return err
case *interface{}:
*d = src
return nil
}
return AssignValue(reflect.ValueOf(dest), src)
}
var (
scannerTypePlaceHolder sql.Scanner
scannerType = reflect.TypeOf(&scannerTypePlaceHolder).Elem()
)
// AssignValue assign src as dv
func AssignValue(dv reflect.Value, src interface{}) error {
if src == nil {
return nil
}
if v, ok := src.(*interface{}); ok {
return AssignValue(dv, *v)
}
if dv.Type().Implements(scannerType) {
return dv.Interface().(sql.Scanner).Scan(src)
}
switch dv.Kind() {
case reflect.Ptr:
if dv.IsNil() {
dv.Set(reflect.New(dv.Type().Elem()))
}
return AssignValue(dv.Elem(), src)
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
i64, err := AsInt64(src)
if err != nil {
err = strconvErr(err)
return fmt.Errorf("converting driver.Value type %T to a %s: %v", src, dv.Kind(), err)
}
dv.SetInt(i64)
return nil
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
u64, err := AsUint64(src)
if err != nil {
err = strconvErr(err)
return fmt.Errorf("converting driver.Value type %T to a %s: %v", src, dv.Kind(), err)
}
dv.SetUint(u64)
return nil
case reflect.Float32, reflect.Float64:
f64, err := AsFloat64(src)
if err != nil {
err = strconvErr(err)
return fmt.Errorf("converting driver.Value type %T to a %s: %v", src, dv.Kind(), err)
}
dv.SetFloat(f64)
return nil
case reflect.String:
dv.SetString(AsString(src))
return nil
case reflect.Bool:
b, err := AsBool(src)
if err != nil {
return err
}
dv.SetBool(b)
return nil
case reflect.Slice, reflect.Map, reflect.Struct, reflect.Array:
data, ok := AsBytes(src)
if !ok {
return fmt.Errorf("convert.AssignValue: src cannot be as bytes %#v", src)
}
if data == nil {
return nil
}
if dv.Kind() != reflect.Ptr {
dv = dv.Addr()
}
return json.Unmarshal(data, dv.Interface())
default:
return fmt.Errorf("convert.AssignValue: unsupported Scan, storing driver.Value type %T into type %T", src, dv.Interface())
}
}