Initial commit

pipe/backend/response.go

@@ -0,0 +1,41 @@
+package backend
+
+import (
+	"errors"
+	"fmt"
+)
+
+// A response to be sent back in answer to a query. Again, some fields may be
+// blank, depending on protocol version.
+//
+// QName, QClass, QType, TTL, Id and Content are present in all versions
+// No additions in version 2
+// ScopeBits and Auth were added in version 3
+type Response struct {
+	ProtocolVersion int
+	ScopeBits       string
+	Auth            string
+	QName           string
+	QClass          string
+	QType           string
+	TTL             string
+	Id              string
+	Content         string
+}
+
+// Gives the response in a serialized form suitable for squirting on the wire
+func (r *Response) String() (string, error) {
+	switch r.ProtocolVersion {
+	case 1, 2:
+		return fmt.Sprintf(
+			"DATA\t%s\t%s\t%s\t%s\t%s\t%s\n",
+			r.QName, r.QClass, r.QType, r.TTL, r.Id, r.Content,
+		), nil
+	case 3:
+		return fmt.Sprintf(
+			"DATA\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\n",
+			r.ScopeBits, r.Auth, r.QName, r.QClass, r.QType, r.TTL, r.Id, r.Content,
+		), nil
+	}
+	return "", errors.New("Unknown protocol version in response")
+}