Merge pull request #37 from nashtsai/scrolling-rs

Scrolling rs

base_test.go

@@ -1873,6 +1873,27 @@ func testIterate(engine *Engine, t *testing.T) {
 	}
 }
 
+func testRows(engine *Engine, t *testing.T) {
+	rows, err := engine.Omit("is_man").Rows(new(Userinfo))
+	if err != nil {
+		t.Error(err)
+		panic(err)
+	}
+	defer rows.Close()
+
+	idx := 0
+	user := new(Userinfo)
+	for rows.Next() {
+		err = rows.Scan(user)
+		if err != nil {
+			t.Error(err)
+			panic(err)
+		}
+		fmt.Println(idx, "--", user)
+		idx++
+	}
+}
+
 type StrangeName struct {
 	Id_t int64 `xorm:"pk autoincr"`
 	Name string
@@ -3500,29 +3521,35 @@ func testNullValue(engine *Engine, t *testing.T) {
 	//  t.Error(errors.New(fmt.Sprintf("inserted value unmatch: [%v]", *nullDataGet.Complex128Ptr)))
 	// }
 
-	/*if (*nullDataGet.TimePtr).Unix() != (*nullDataUpdate.TimePtr).Unix() {
+	// !nashtsai! skipped mymysql test due to driver will round up time caused inaccuracy comparison
+	// skipped postgres test due to postgres driver doesn't read time.Time's timzezone info when stored in the db
+	// mysql and sqlite3 seem have done this correctly by storing datatime in UTC timezone, I think postgres driver
+	// prefer using timestamp with timezone to sovle the issue
+	if engine.DriverName != POSTGRES && engine.DriverName != MYMYSQL {
+		if (*nullDataGet.TimePtr).Unix() != (*nullDataUpdate.TimePtr).Unix() {
 			t.Error(errors.New(fmt.Sprintf("inserted value unmatch: [%v]:[%v]", *nullDataGet.TimePtr, *nullDataUpdate.TimePtr)))
 		} else {
 			// !nashtsai! mymysql driver will failed this test case, due the time is roundup to nearest second, I would considered this is a bug in mymysql driver
+			//  inserted value unmatch: [2013-12-25 12:12:45 +0800 CST]:[2013-12-25 12:12:44.878903653 +0800 CST]
 			fmt.Printf("time value: [%v]:[%v]", *nullDataGet.TimePtr, *nullDataUpdate.TimePtr)
 			fmt.Println()
-	  }*/
+		}
-	// --
+	}
 
 	// update to null values
-	/*nullDataUpdate = NullData{}
+	nullDataUpdate = NullData{}
 
-	  cnt, err = engine.Id(nullData.Id).Update(&nullDataUpdate)
+	cnt, err = engine.Id(nullData.Id).Cols("string_ptr").Update(&nullDataUpdate)
 	if err != nil {
 		t.Error(err)
 		panic(err)
 	} else if cnt != 1 {
 		t.Error(errors.New("update count == 0, how can this happen!?"))
 		return
-	  }*/
+	}
 
 	// verify get values
-	/*nullDataGet = NullData{}
+	nullDataGet = NullData{}
 	has, err = engine.Id(nullData.Id).Get(&nullDataGet)
 	if err != nil {
 		t.Error(err)
@@ -3538,7 +3565,7 @@ func testNullValue(engine *Engine, t *testing.T) {
 	if nullDataGet.StringPtr != nil {
 		t.Error(errors.New(fmt.Sprintf("not null value: [%v]", *nullDataGet.StringPtr)))
 	}
-
+	/*
 	  if nullDataGet.StringPtr2 != nil {
 	      t.Error(errors.New(fmt.Sprintf("not null value: [%v]", *nullDataGet.StringPtr2)))
 	  }
@@ -3829,6 +3856,8 @@ func testAll2(engine *Engine, t *testing.T) {
 	testMetaInfo(engine, t)
 	fmt.Println("-------------- testIterate --------------")
 	testIterate(engine, t)
+	fmt.Println("-------------- testRows --------------")
+	testRows(engine, t)
 	fmt.Println("-------------- testStrangeName --------------")
 	testStrangeName(engine, t)
 	fmt.Println("-------------- testVersion --------------")

engine.go

@@ -934,6 +934,13 @@ func (engine *Engine) Iterate(bean interface{}, fun IterFunc) error {
 	return session.Iterate(bean, fun)
 }
 
+// Return sql.Rows compatible Rows obj, as a forward Iterator object for iterating record by record, bean's non-empty fields
+// are conditions.
+func (engine *Engine) Rows(bean interface{}) (*Rows, error) {
+	session := engine.NewSession()
+	return session.Rows(bean)
+}
+
 // Count counts the records. bean's non-empty fields
 // are conditions.
 func (engine *Engine) Count(bean interface{}) (int64, error) {

mysql_test.go

@@ -12,8 +12,6 @@ CREATE DATABASE IF NOT EXISTS xorm_test CHARACTER SET
 utf8 COLLATE utf8_general_ci;
 */
 
-var mysqlShowTestSql bool = true
-
 func TestMysql(t *testing.T) {
 	err := mysqlDdlImport()
 	if err != nil {
@@ -27,10 +25,10 @@ func TestMysql(t *testing.T) {
 		t.Error(err)
 		return
 	}
-	engine.ShowSQL = mysqlShowTestSql
+	engine.ShowSQL = showTestSql
-	engine.ShowErr = mysqlShowTestSql
+	engine.ShowErr = showTestSql
-	engine.ShowWarn = mysqlShowTestSql
+	engine.ShowWarn = showTestSql
-	engine.ShowDebug = mysqlShowTestSql
+	engine.ShowDebug = showTestSql
 
 	testAll(engine, t)
 	testAll2(engine, t)
@@ -51,10 +49,10 @@ func TestMysqlWithCache(t *testing.T) {
 		return
 	}
 	engine.SetDefaultCacher(NewLRUCacher(NewMemoryStore(), 1000))
-	engine.ShowSQL = mysqlShowTestSql
+	engine.ShowSQL = showTestSql
-	engine.ShowErr = mysqlShowTestSql
+	engine.ShowErr = showTestSql
-	engine.ShowWarn = mysqlShowTestSql
+	engine.ShowWarn = showTestSql
-	engine.ShowDebug = mysqlShowTestSql
+	engine.ShowDebug = showTestSql
 
 	testAll(engine, t)
 	testAll2(engine, t)
@@ -69,10 +67,10 @@ func mysqlDdlImport() error {
 	if err != nil {
 		return err
 	}
-	engine.ShowSQL = mysqlShowTestSql
+	engine.ShowSQL = showTestSql
-	engine.ShowErr = mysqlShowTestSql
+	engine.ShowErr = showTestSql
-	engine.ShowWarn = mysqlShowTestSql
+	engine.ShowWarn = showTestSql
-	engine.ShowDebug = mysqlShowTestSql
+	engine.ShowDebug = showTestSql
 
 	sqlResults, _ := engine.Import("tests/mysql_ddl.sql")
 	engine.LogDebug("sql results: %v", sqlResults)

rows.go

@@ -0,0 +1,141 @@
+package xorm
+
+import (
+	"database/sql"
+	"fmt"
+	"reflect"
+)
+
+type Rows struct {
+	NoTypeCheck bool
+
+	session   *Session
+	stmt      *sql.Stmt
+	rows      *sql.Rows
+	fields    []string
+	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()
+
+	err := rows.session.newDb()
+	if err != nil {
+		return nil, err
+	}
+
+	defer rows.session.Statement.Init()
+
+	var sql string
+	var args []interface{}
+	rows.session.Statement.RefTable = rows.session.Engine.autoMap(bean)
+	if rows.session.Statement.RawSQL == "" {
+		sql, args = rows.session.Statement.genGetSql(bean)
+	} else {
+		sql = rows.session.Statement.RawSQL
+		args = rows.session.Statement.RawParams
+	}
+
+	for _, filter := range rows.session.Engine.Filters {
+		sql = filter.Do(sql, session)
+	}
+
+	rows.session.Engine.LogSQL(sql)
+	rows.session.Engine.LogSQL(args)
+
+	rows.stmt, err = rows.session.Db.Prepare(sql)
+	if err != nil {
+		rows.lastError = err
+		defer rows.Close()
+		return nil, err
+	}
+
+	rows.rows, err = rows.stmt.Query(args...)
+	if err != nil {
+		rows.lastError = err
+		defer rows.Close()
+		return nil, err
+	}
+
+	rows.fields, err = rows.rows.Columns()
+	if err != nil {
+		rows.lastError = err
+		defer rows.Close()
+		return nil, err
+	}
+
+	return rows, nil
+}
+
+// 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 !rows.NoTypeCheck && reflect.Indirect(reflect.ValueOf(bean)).Type() != rows.beanType {
+		return fmt.Errorf("scan arg is incompatible type to [%v]", rows.beanType)
+	}
+
+	result, err := row2map(rows.rows, rows.fields) // !nashtsai! TODO remove row2map then scanMapIntoStruct conversation for better performance
+	if err == nil {
+		err = rows.session.scanMapIntoStruct(bean, result)
+	}
+	return err
+}
+
+// // Columns returns the column names. Columns returns an error if the rows are closed, or if the rows are from QueryRow and there was a deferred error.
+// func (rows *Rows) Columns() ([]string, error) {
+// 	if rows.lastError == nil && rows.rows != nil {
+// 		return rows.rows.Columns()
+// 	}
+// 	return nil, rows.lastError
+// }
+
+// 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.lastError == nil {
+		if rows.rows != nil {
+			rows.lastError = rows.rows.Close()
+			if rows.lastError != nil {
+				defer rows.stmt.Close()
+				return rows.lastError
+			}
+		}
+		if rows.stmt != nil {
+			rows.lastError = rows.stmt.Close()
+		}
+	} else {
+		if rows.stmt != nil {
+			defer rows.stmt.Close()
+		}
+		if rows.rows != nil {
+			defer rows.rows.Close()
+		}
+	}
+	return rows.lastError
+}

session.go

@@ -24,9 +24,6 @@ type Session struct {
 	IsAutoClose            bool
 
 	// !nashtsai! storing these beans due to yet committed tx
-	// afterInsertBeans []interface{}
-	// afterUpdateBeans []interface{}
-	// afterDeleteBeans []interface{}
 	afterInsertBeans map[interface{}]*[]func(interface{})
 	afterUpdateBeans map[interface{}]*[]func(interface{})
 	afterDeleteBeans map[interface{}]*[]func(interface{})
@@ -835,69 +832,38 @@ func (session *Session) cacheFind(t reflect.Type, sql string, rowsSlicePtr inter
 // IterFunc only use by Iterate
 type IterFunc func(idx int, bean interface{}) error
 
+// Return sql.Rows compatible Rows obj, as a forward Iterator object for iterating record by record, bean's non-empty fields
+// are conditions.
+func (session *Session) Rows(bean interface{}) (*Rows, error) {
+	return newRows(session, bean)
+}
+
 // Iterate record by record handle records from table, condiBeans's non-empty fields
 // are conditions. beans could be []Struct, []*Struct, map[int64]Struct
 // map[int64]*Struct
 func (session *Session) Iterate(bean interface{}, fun IterFunc) error {
-	err := session.newDb()
+
+	rows, err := session.Rows(bean)
 	if err != nil {
 		return err
-	}
-
-	defer session.Statement.Init()
-	if session.IsAutoClose {
-		defer session.Close()
-	}
-
-	var sql string
-	var args []interface{}
-	session.Statement.RefTable = session.Engine.autoMap(bean)
-	if session.Statement.RawSQL == "" {
-		sql, args = session.Statement.genGetSql(bean)
 	} else {
-		sql = session.Statement.RawSQL
-		args = session.Statement.RawParams
-	}
-
-	for _, filter := range session.Engine.Filters {
-		sql = filter.Do(sql, session)
-	}
-
-	session.Engine.LogSQL(sql)
-	session.Engine.LogSQL(args)
-
-	s, err := session.Db.Prepare(sql)
-	if err != nil {
-		return err
-	}
-	defer s.Close()
-	rows, err := s.Query(args...)
-	if err != nil {
-		return err
-	}
 		defer rows.Close()
-
+		//b := reflect.New(iterator.beanType).Interface()
-	fields, err := rows.Columns()
-	if err != nil {
-		return err
-	}
-	t := reflect.Indirect(reflect.ValueOf(bean)).Type()
-	b := reflect.New(t).Interface()
 		i := 0
 		for rows.Next() {
-		result, err := row2map(rows, fields)
+			b := reflect.New(rows.beanType).Interface()
-		if err == nil {
+			err = rows.Scan(b)
-			err = session.scanMapIntoStruct(b, result)
-		}
-		if err == nil {
-			err = fun(i, b)
-			i = i + 1
-		}
 			if err != nil {
 				return err
 			}
+			err = fun(i, b)
+			if err != nil {
+				return err
+			}
+			i++
+		}
+		return err
 	}
-
 	return nil
 }
 
@@ -1770,6 +1736,9 @@ func (session *Session) bytes2Value(col *Column, fieldValue *reflect.Value, data
 					return errors.New("arg " + key + " as int: " + err.Error())
 				}
 				if x != 0 {
+					// !nashtsai! TODO for hasOne relationship, it's preferred to use join query for eager fetch
+					// however, also need to consider adding a 'lazy' attribute to xorm tag which allow hasOne
+					// property to be fetched lazily
 					structInter := reflect.New(fieldValue.Type())
 					newsession := session.Engine.NewSession()
 					defer newsession.Close()