// Encode encodes a packet to be sent from the server to client into an array of
// bytes. The values of each field are encoded into the byte array according to
// their type.
//
// Once all of the data is serialized, the length and ID will be written in
// front of it, according to the specification given in `connection.go` from
// L41-L46.
//
// If an error occurs during encoding, an empty byte array and that
// error will be returned.
func (d *Dealer) Encode(h packet.Holder) ([]byte, error) {
out := new(bytes.Buffer)
out.Write(util.Uvarint(uint32(h.ID())))
v := reflect.ValueOf(h)
for i := 0; i < v.NumField(); i++ {
ftype, ok := v.Field(i).Interface().(types.Type)
if !ok {
// XXX(taylor): special-casing
ftype = types.JSON{V: v.Field(i).Interface()}
}
if _, err := ftype.Encode(out); err != nil {
return nil, err
}
}
return append(
util.Uvarint(uint32(out.Len())),
out.Bytes()...,
), nil
}
func (s String) Encode(w io.Writer) (int, error) {
var n int
var err error
length := util.Uvarint(uint32(len(s)))
written, err := w.Write(length)
n += written
if err != nil {
return written, err
}
written, err = w.Write([]byte(s))
n += written
if err != nil {
return written, err
}
return written, nil
}
func (u UVarint) Encode(w io.Writer) (int, error) {
return w.Write(util.Uvarint(uint32(u)))
}