feat: simple string keys in ScanStruct (#692)

Support simple string keys in ScanStruct so it can be used to scan
the results of FT.INFO and similar commands.

Fixes: #691

Author: stevenh

redis/scan.go

@@ -477,7 +477,7 @@ var errScanStructValue = errors.New("redigo.ScanStruct: value must be non-nil po
 // ScanStruct uses exported field names to match values in the response. Use
 // 'redis' field tag to override the name:
 //
-//      Field int `redis:"myName"`
+//	Field int `redis:"myName"`
 //
 // Fields with the tag redis:"-" are ignored.
 //
@@ -513,9 +513,9 @@ func ScanStruct(src []interface{}, dest interface{}) error {
 			continue
 		}
 
-		name, ok := src[i].([]byte)
+		name, ok := convertToBulk(src[i])
 		if !ok {
-			return fmt.Errorf("redigo.ScanStruct: key %d not a bulk string value", i)
+			return fmt.Errorf("redigo.ScanStruct: key %d not a bulk string value got type: %T", i, src[i])
 		}
 
 		fs := ss.fieldSpec(name)
@@ -530,6 +530,19 @@ func ScanStruct(src []interface{}, dest interface{}) error {
 	return nil
 }
 
+// convertToBulk converts src to a []byte if src is a string or bulk string
+// and returns true. Otherwise nil and false is returned.
+func convertToBulk(src interface{}) ([]byte, bool) {
+	switch v := src.(type) {
+	case []byte:
+		return v, true
+	case string:
+		return []byte(v), true
+	default:
+		return nil, false
+	}
+}
+
 var (
 	errScanSliceValue = errors.New("redigo.ScanSlice: dest must be non-nil pointer to a struct")
 )

redis/scan_test.go

@@ -327,6 +327,22 @@ func TestScanStruct(t *testing.T) {
 	}
 }
 
+func TestScanStructStringKeys(t *testing.T) {
+	reply := []interface{}{"simple", []byte("value"), "number", []byte("123")}
+	expected := &struct {
+		Simple string `redis:"simple"`
+		Number int    `redis:"number"`
+	}{
+		Simple: "value",
+		Number: 123,
+	}
+
+	value := reflect.New(reflect.ValueOf(expected).Type().Elem()).Interface()
+	err := redis.ScanStruct(reply, value)
+	require.NoError(t, err)
+	require.Equal(t, expected, value)
+}
+
 func TestBadScanStructArgs(t *testing.T) {
 	x := []interface{}{"A", "b"}
 	test := func(v interface{}) {