Add a Map and MapInto

Turn a row into a map[string]any

Author: karlseguin

row.go

@@ -5,6 +5,28 @@ type Row struct {
 	err  error
 }
 
+func (r Row) Map() (map[string]any, error) {
+	m := make(map[string]any, r.Stmt.columnCount)
+	err := r.MapInto(m)
+	return m, err
+}
+
+func (r Row) MapInto(m map[string]any) error {
+	stmt := r.Stmt
+	defer stmt.Close()
+
+	hasRow, err := stmt.Step()
+	if err != nil {
+		return err
+	}
+
+	if !hasRow {
+		return ErrNoRows
+	}
+
+	return stmt.MapInto(m)
+}
+
 func (r Row) Scan(dst ...interface{}) error {
 	if err := r.err; err != nil {
 		return err

sqlite3_test.go

@@ -37,7 +37,7 @@ func Test_Conn_ExecAndScan(t *testing.T) {
 
 	now := time.Now()
 	mustExec(db, `
-		insert into test (cint, creal, ctext, cblob, time)
+		insert into test (cint, creal, ctext, cblob, ctime)
 		values (?1, ?2, ?3, ?4, ?5)
 	`, 1, 2.2, "three", []byte("four"), now)
 	assert.Equal(t, db.Changes(), 1)
@@ -289,6 +289,34 @@ func Test_Rows_ScanError(t *testing.T) {
 	assert.Equal(t, rows.Error().Error(), "sqlite: cannot scan into *os.File (index: 0) (code: 21)")
 }
 
+func Test_Row_Map(t *testing.T) {
+	db := testDB()
+	defer db.Close()
+
+	now := time.Now()
+
+	mustExec(db, `
+		insert into test (id, cint, creal, ctext, cblob, ctime)
+		values (?1, ?2, ?3, ?4, ?5, ?6)
+	`, 99, 2, 3.3, "four", []byte("five"), now)
+
+	m, err := db.Row("select * from test").Map()
+	assert.Nil(t, err)
+	assert.Equal(t, len(m), 11)
+
+	assert.Equal(t, m["id"].(int), 99)
+	assert.Equal(t, m["cint"].(int), 2)
+	assert.Nil(t, m["cintn"])
+	assert.Equal(t, m["creal"].(float64), 3.3)
+	assert.Nil(t, m["crealn"])
+	assert.Equal(t, m["ctext"].(string), "four")
+	assert.Nil(t, m["ctextn"])
+	assert.Equal(t, string(m["cblob"].([]byte)), "five")
+	assert.Nil(t, m["cblobn"])
+	assert.Equal(t, m["ctime"].(int), int(now.Unix()))
+	assert.Nil(t, m["ctimen"])
+}
+
 func testDB() sqlite.Conn {
 	db, err := sqlite.Open(":memory:", true)
 	if err != nil {
@@ -305,8 +333,8 @@ func testDB() sqlite.Conn {
 			ctextn text null,
 			cblob blob not null default(''),
 			cblobn blob null,
-			time int not null default(0),
-			timen int null
+			ctime int not null default(0),
+			ctimen int null
 		)
 	`)
 	return db

stmt.go

@@ -39,6 +39,7 @@ type Stmt struct {
 	columnTypes  []byte
 	cColumnTypes *C.uchar
 	cColumnCount C.int
+	columnNames  []string
 }
 
 func (s *Stmt) Close() error {
@@ -50,12 +51,17 @@ func (s *Stmt) Close() error {
 }
 
 func (s *Stmt) ColumnNames() []string {
+	if names := s.columnNames; names != nil {
+		return names
+	}
+
 	stmt := s.stmt
 	count := s.columnCount
 	names := make([]string, count)
 	for i := 0; i < count; i++ {
 		names[i] = C.GoString(C.sqlite3_column_name(stmt, C.int(i)))
 	}
+	s.columnNames = names
 	return names
 }
 
@@ -134,6 +140,45 @@ func (s *Stmt) Bind(args ...interface{}) error {
 	return nil
 }
 
+func (s *Stmt) Map() (map[string]any, error) {
+	m := make(map[string]any, s.columnCount)
+	err := s.MapInto(m)
+	return m, err
+}
+
+func (s *Stmt) MapInto(m map[string]any) error {
+	names := s.ColumnNames()
+	for i, tpe := range s.columnTypes {
+		name := names[i]
+		switch tpe {
+		case C.SQLITE_NULL:
+			m[name] = nil
+			break
+		case C.SQLITE_INTEGER:
+			m[name] = s.ColumnInt(i)
+			break
+		case C.SQLITE_TEXT:
+			var err error
+			m[name], err = s.ColumnText(i)
+			if err != nil {
+				return err
+			}
+			break
+		case C.SQLITE_FLOAT:
+			m[name] = s.ColumnDouble(i)
+			break
+		case C.SQLITE_BLOB:
+			var err error
+			m[name], err = s.ColumnBytes(i)
+			if err != nil {
+				return err
+			}
+			break
+		}
+	}
+	return nil
+}
+
 func (s *Stmt) Scan(dst ...interface{}) error {
 	for i, v := range dst {
 		if err := s.scan(i, v); err != nil {