Add Multi-Results support

Fixes go-sql-driver#420
jszwec · Jan 10, 2017 · f282f2b · f282f2b
1 parent 2e00b5c
commit f282f2b
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Showing 6 changed files with 178 additions and 39 deletions.
diff --git a/AUTHORS b/AUTHORS
@@ -25,6 +25,7 @@ Hanno Braun <mail at hannobraun.com>
 Henri Yandell <flamefew at gmail.com>
 Hirotaka Yamamoto <ymmt2005 at gmail.com>
 INADA Naoki <songofacandy at gmail.com>
+Jacek Szwec <szwec.jacek at gmail.com>
 James Harr <james.harr at gmail.com>
 Jian Zhen <zhenjl at gmail.com>
 Joshua Prunier <joshua.prunier at gmail.com>

diff --git a/connection.go b/connection.go
@@ -331,15 +331,13 @@ func (mc *mysqlConn) Query(query string, args []driver.Value) (driver.Rows, erro
 		var resLen int
 		resLen, err = mc.readResultSetHeaderPacket()
 		if err == nil {
-			rows := new(textRows)
-			rows.mc = mc
-
+			rows := newTextRows(mc)
 			if resLen == 0 {
 				// no columns, no more data
 				return emptyRows{}, nil
 			}
 			// Columns
-			rows.columns, err = mc.readColumns(resLen)
+			rows.rs.columns, err = mc.readColumns(resLen)
 			return rows, err
 		}
 	}
@@ -357,9 +355,8 @@ func (mc *mysqlConn) getSystemVar(name string) ([]byte, error) {
 	// Read Result
 	resLen, err := mc.readResultSetHeaderPacket()
 	if err == nil {
-		rows := new(textRows)
-		rows.mc = mc
-		rows.columns = []mysqlField{{fieldType: fieldTypeVarChar}}
+		rows := newTextRows(mc)
+		rows.rs.columns = []mysqlField{{fieldType: fieldTypeVarChar}}
 
 		if resLen > 0 {
 			// Columns

diff --git a/driver_18_test.go b/driver_18_test.go
@@ -0,0 +1,93 @@
+// +build go1.8
+
+package mysql
+
+import (
+	"reflect"
+	"testing"
+)
+
+func TestMultiResultSet(t *testing.T) {
+	runTests(t, dsn, func(dbt *DBTest) {
+		type result struct {
+			values  [][]int
+			columns []string
+		}
+
+		expected := []result{
+			{
+				values:  [][]int{{1, 2}, {3, 4}},
+				columns: []string{"col1", "col2"},
+			},
+			{
+				values:  [][]int{{1, 2, 3}, {4, 5, 6}},
+				columns: []string{"col1", "col2", "col3"},
+			},
+		}
+
+		query := `
+SELECT 1 AS col1, 2 AS col2 UNION SELECT 3, 4;
+SELECT 1 AS col1, 2 AS col2, 3 AS col3 UNION SELECT 4, 5, 6`
+
+		rows := dbt.mustQuery(query)
+		defer rows.Close()
+
+		var res1 result
+		for rows.Next() {
+			var res [2]int
+			if err := rows.Scan(&res[0], &res[1]); err != nil {
+				dbt.Fatal(err)
+			}
+			res1.values = append(res1.values, res[:])
+		}
+
+		if rows.Next() {
+			dbt.Error("unexpected row")
+		}
+
+		cols, err := rows.Columns()
+		if err != nil {
+			dbt.Fatal(err)
+		}
+		res1.columns = cols
+
+		if !reflect.DeepEqual(expected[0], res1) {
+			dbt.Error("want =", expected[0], "got =", res1)
+		}
+
+		if !rows.NextResultSet() {
+			dbt.Fatal("expected next result set")
+		}
+
+		var res2 result
+		cols, err = rows.Columns()
+		if err != nil {
+			dbt.Fatal(err)
+		}
+		res2.columns = cols
+
+		for rows.Next() {
+			var res [3]int
+			if err := rows.Scan(&res[0], &res[1], &res[2]); err != nil {
+				dbt.Fatal(err)
+			}
+			res2.values = append(res2.values, res[:])
+		}
+
+		if !reflect.DeepEqual(expected[1], res2) {
+			dbt.Error("want =", expected[1], "got =", res2)
+		}
+
+		if rows.Next() {
+			dbt.Error("unexpected row")
+		}
+
+		if rows.NextResultSet() {
+			dbt.Error("unexpected next result set")
+		}
+
+		if err := rows.Err(); err != nil {
+			dbt.Error(err)
+		}
+	})
+}
diff --git a/packets.go b/packets.go
@@ -231,6 +231,7 @@ func (mc *mysqlConn) writeAuthPacket(cipher []byte) error {
 		clientTransactions |
 		clientLocalFiles |
 		clientPluginAuth |
+		clientMultiStatements |
 		clientMultiResults |
 		mc.flags&clientLongFlag
 
@@ -698,6 +699,10 @@ func (mc *mysqlConn) readColumns(count int) ([]mysqlField, error) {
 func (rows *textRows) readRow(dest []driver.Value) error {
 	mc := rows.mc
 
+	if rows.rs.done {
+		return io.EOF
+	}
+
 	data, err := mc.readPacket()
 	if err != nil {
 		return err
@@ -707,15 +712,11 @@ func (rows *textRows) readRow(dest []driver.Value) error {
 	if data[0] == iEOF && len(data) == 5 {
 		// server_status [2 bytes]
 		rows.mc.status = readStatus(data[3:])
-		err = rows.mc.discardResults()
-		if err == nil {
-			err = io.EOF
-		} else {
-			// connection unusable
-			rows.mc.Close()
+		rows.rs.done = true
+		if !rows.HasNextResultSet() {
+			rows.mc = nil
 		}
-		rows.mc = nil
-		return err
+		return io.EOF
 	}
 	if data[0] == iERR {
 		rows.mc = nil
@@ -736,7 +737,7 @@ func (rows *textRows) readRow(dest []driver.Value) error {
 				if !mc.parseTime {
 					continue
 				} else {
-					switch rows.columns[i].fieldType {
+					switch rows.rs.columns[i].fieldType {
 					case fieldTypeTimestamp, fieldTypeDateTime,
 						fieldTypeDate, fieldTypeNewDate:
 						dest[i], err = parseDateTime(
@@ -1145,14 +1146,14 @@ func (rows *binaryRows) readRow(dest []driver.Value) error {
 		}
 
 		// Convert to byte-coded string
-		switch rows.columns[i].fieldType {
+		switch rows.rs.columns[i].fieldType {
 		case fieldTypeNULL:
 			dest[i] = nil
 			continue
 
 		// Numeric Types
 		case fieldTypeTiny:
-			if rows.columns[i].flags&flagUnsigned != 0 {
+			if rows.rs.columns[i].flags&flagUnsigned != 0 {
 				dest[i] = int64(data[pos])
 			} else {
 				dest[i] = int64(int8(data[pos]))
@@ -1161,7 +1162,7 @@ func (rows *binaryRows) readRow(dest []driver.Value) error {
 			continue
 
 		case fieldTypeShort, fieldTypeYear:
-			if rows.columns[i].flags&flagUnsigned != 0 {
+			if rows.rs.columns[i].flags&flagUnsigned != 0 {
 				dest[i] = int64(binary.LittleEndian.Uint16(data[pos : pos+2]))
 			} else {
 				dest[i] = int64(int16(binary.LittleEndian.Uint16(data[pos : pos+2])))
@@ -1170,7 +1171,7 @@ func (rows *binaryRows) readRow(dest []driver.Value) error {
 			continue
 
 		case fieldTypeInt24, fieldTypeLong:
-			if rows.columns[i].flags&flagUnsigned != 0 {
+			if rows.rs.columns[i].flags&flagUnsigned != 0 {
 				dest[i] = int64(binary.LittleEndian.Uint32(data[pos : pos+4]))
 			} else {
 				dest[i] = int64(int32(binary.LittleEndian.Uint32(data[pos : pos+4])))
@@ -1179,7 +1180,7 @@ func (rows *binaryRows) readRow(dest []driver.Value) error {
 			continue
 
 		case fieldTypeLongLong:
-			if rows.columns[i].flags&flagUnsigned != 0 {
+			if rows.rs.columns[i].flags&flagUnsigned != 0 {
 				val := binary.LittleEndian.Uint64(data[pos : pos+8])
 				if val > math.MaxInt64 {
 					dest[i] = uint64ToString(val)
@@ -1233,37 +1234,37 @@ func (rows *binaryRows) readRow(dest []driver.Value) error {
 			case isNull:
 				dest[i] = nil
 				continue
-			case rows.columns[i].fieldType == fieldTypeTime:
+			case rows.rs.columns[i].fieldType == fieldTypeTime:
 				// database/sql does not support an equivalent to TIME, return a string
 				var dstlen uint8
-				switch decimals := rows.columns[i].decimals; decimals {
+				switch decimals := rows.rs.columns[i].decimals; decimals {
 				case 0x00, 0x1f:
 					dstlen = 8
 				case 1, 2, 3, 4, 5, 6:
 					dstlen = 8 + 1 + decimals
 				default:
 					return fmt.Errorf(
 						"protocol error, illegal decimals value %d",
-						rows.columns[i].decimals,
+						rows.rs.columns[i].decimals,
 					)
 				}
 				dest[i], err = formatBinaryDateTime(data[pos:pos+int(num)], dstlen, true)
 			case rows.mc.parseTime:
 				dest[i], err = parseBinaryDateTime(num, data[pos:], rows.mc.cfg.Loc)
 			default:
 				var dstlen uint8
-				if rows.columns[i].fieldType == fieldTypeDate {
+				if rows.rs.columns[i].fieldType == fieldTypeDate {
 					dstlen = 10
 				} else {
-					switch decimals := rows.columns[i].decimals; decimals {
+					switch decimals := rows.rs.columns[i].decimals; decimals {
 					case 0x00, 0x1f:
 						dstlen = 19
 					case 1, 2, 3, 4, 5, 6:
 						dstlen = 19 + 1 + decimals
 					default:
 						return fmt.Errorf(
 							"protocol error, illegal decimals value %d",
-							rows.columns[i].decimals,
+							rows.rs.columns[i].decimals,
 						)
 					}
 				}
@@ -1279,7 +1280,7 @@ func (rows *binaryRows) readRow(dest []driver.Value) error {
 
 		// Please report if this happens!
 		default:
-			return fmt.Errorf("unknown field type %d", rows.columns[i].fieldType)
+			return fmt.Errorf("unknown field type %d", rows.rs.columns[i].fieldType)
 		}
 	}
 

diff --git a/rows.go b/rows.go
@@ -21,9 +21,14 @@ type mysqlField struct {
 	decimals  byte
 }
 
-type mysqlRows struct {
-	mc      *mysqlConn
+type resultSet struct {
 	columns []mysqlField
+	done    bool
+}
+
+type mysqlRows struct {
+	mc *mysqlConn
+	rs *resultSet
 }
 
 type binaryRows struct {
@@ -34,21 +39,33 @@ type textRows struct {
 	mysqlRows
 }
 
+func newTextRows(mc *mysqlConn) *textRows {
+	return &textRows{
+		mysqlRows{
+			mc: mc,
+			rs: new(resultSet),
+		},
+	}
+}
+
 type emptyRows struct{}
 
 func (rows *mysqlRows) Columns() []string {
-	columns := make([]string, len(rows.columns))
+	if rows.rs == nil {
+		return []string{}
+	}
+	columns := make([]string, len(rows.rs.columns))
 	if rows.mc != nil && rows.mc.cfg.ColumnsWithAlias {
 		for i := range columns {
-			if tableName := rows.columns[i].tableName; len(tableName) > 0 {
-				columns[i] = tableName + "." + rows.columns[i].name
+			if tableName := rows.rs.columns[i].tableName; len(tableName) > 0 {
+				columns[i] = tableName + "." + rows.rs.columns[i].name
 			} else {
-				columns[i] = rows.columns[i].name
+				columns[i] = rows.rs.columns[i].name
 			}
 		}
 	} else {
 		for i := range columns {
-			columns[i] = rows.columns[i].name
+			columns[i] = rows.rs.columns[i].name
 		}
 	}
 	return columns
@@ -99,6 +116,26 @@ func (rows *textRows) Next(dest []driver.Value) error {
 	return io.EOF
 }
 
+func (rows *textRows) HasNextResultSet() (b bool) {
+	if rows.mc == nil {
+		return false
+	}
+	return rows.mc.status&statusMoreResultsExists != 0
+}
+
+func (rows *textRows) NextResultSet() error {
+	if !rows.HasNextResultSet() {
+		return io.EOF
+	}
+	rows.rs = new(resultSet)
+	resLen, err := rows.mc.readResultSetHeaderPacket()
+	if err != nil {
+		return err
+	}
+	rows.rs.columns, err = rows.mc.readColumns(resLen)
+	return err
+}
+
 func (rows emptyRows) Columns() []string {
 	return nil
 }
@@ -110,3 +147,11 @@ func (rows emptyRows) Close() error {
 func (rows emptyRows) Next(dest []driver.Value) error {
 	return io.EOF
 }
+
+func (rows emptyRows) HasNextResultSet() bool {
+	return false
+}
+
+func (rows emptyRows) NextResultSet() error {
+	return io.EOF
+}
diff --git a/statement.go b/statement.go
@@ -103,17 +103,19 @@ func (stmt *mysqlStmt) Query(args []driver.Value) (driver.Rows, error) {
 		return nil, err
 	}
 
-	rows := new(binaryRows)
+	rows := &binaryRows{
+		mysqlRows{rs: new(resultSet)},
+	}
 
 	if resLen > 0 {
 		rows.mc = mc
 		// Columns
 		// If not cached, read them and cache them
 		if stmt.columns == nil {
-			rows.columns, err = mc.readColumns(resLen)
-			stmt.columns = rows.columns
+			rows.rs.columns, err = mc.readColumns(resLen)
+			stmt.columns = rows.rs.columns
 		} else {
-			rows.columns = stmt.columns
+			rows.rs.columns = stmt.columns
 			err = mc.readUntilEOF()
 		}
 	}