Extracted and generalized encoding logic to encoding.go

go/sql/encoding.go

@@ -0,0 +1,21 @@
+/*
+   Copyright 2016 GitHub Inc.
+	 See https://github.com/github/gh-ost/blob/master/LICENSE
+*/
+
+package sql
+
+import (
+	"golang.org/x/text/encoding"
+	"golang.org/x/text/encoding/charmap"
+)
+
+type charsetEncoding map[string]encoding.Encoding
+
+var charsetEncodingMap charsetEncoding
+
+func init() {
+	charsetEncodingMap = make(map[string]encoding.Encoding)
+	// Begin mappings
+	charsetEncodingMap["latin1"] = charmap.Windows1252
+}

go/sql/types.go

@@ -10,8 +10,6 @@ import (
 	"reflect"
 	"strconv"
 	"strings"
-
-	"golang.org/x/text/encoding/charmap"
 )
 
 type Column struct {
@@ -22,9 +20,9 @@ type Column struct {
 
 func (this *Column) convertArg(arg interface{}) interface{} {
 	if s, ok := arg.(string); ok {
-		switch this.Charset {
-		case "latin1":
-			arg, _ = charmap.Windows1252.NewDecoder().String(s)
+		// string, charset conversion
+		if encoding, ok := charsetEncodingMap[this.Charset]; ok {
+			arg, _ = encoding.NewDecoder().String(s)
 		}
 		return arg
 	}