xorm/rows.go

122 lines
2.6 KiB
Go

// Copyright 2015 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 xorm
import (
"database/sql"
"fmt"
"reflect"
"xorm.io/core"
)
// Rows rows wrapper a rows to
type Rows struct {
session *Session
rows *core.Rows
beanType reflect.Type
lastError error
}
func newRows(session *Session, bean interface{}) (*Rows, error) {
rows := new(Rows)
rows.session = session
rows.beanType = reflect.Indirect(reflect.ValueOf(bean)).Type()
var sqlStr string
var args []interface{}
var err error
if err = rows.session.statement.setRefBean(bean); err != nil {
return nil, err
}
if len(session.statement.TableName()) <= 0 {
return nil, ErrTableNotFound
}
if rows.session.statement.RawSQL == "" {
sqlStr, args, err = rows.session.statement.genGetSQL(bean)
if err != nil {
return nil, err
}
} else {
sqlStr = rows.session.statement.RawSQL
args = rows.session.statement.RawParams
}
rows.rows, err = rows.session.queryRows(sqlStr, args...)
if err != nil {
rows.lastError = err
rows.Close()
return nil, err
}
return rows, nil
}
// Next move cursor to next record, return false if end has reached
func (rows *Rows) Next() bool {
if rows.lastError == nil && rows.rows != nil {
hasNext := rows.rows.Next()
if !hasNext {
rows.lastError = sql.ErrNoRows
}
return hasNext
}
return false
}
// Err returns the error, if any, that was encountered during iteration. Err may be called after an explicit or implicit Close.
func (rows *Rows) Err() error {
return rows.lastError
}
// Scan row record to bean properties
func (rows *Rows) Scan(bean interface{}) error {
if rows.lastError != nil {
return rows.lastError
}
if reflect.Indirect(reflect.ValueOf(bean)).Type() != rows.beanType {
return fmt.Errorf("scan arg is incompatible type to [%v]", rows.beanType)
}
if err := rows.session.statement.setRefBean(bean); err != nil {
return err
}
fields, err := rows.rows.Columns()
if err != nil {
return err
}
scanResults, err := rows.session.row2Slice(rows.rows, fields, bean)
if err != nil {
return err
}
dataStruct := rValue(bean)
_, err = rows.session.slice2Bean(scanResults, fields, bean, &dataStruct, rows.session.statement.RefTable)
if err != nil {
return err
}
return rows.session.executeProcessors()
}
// Close session if session.IsAutoClose is true, and claimed any opened resources
func (rows *Rows) Close() error {
if rows.session.isAutoClose {
defer rows.session.Close()
}
if rows.rows != nil {
return rows.rows.Close()
}
return rows.lastError
}