// will be spawned as a go-routine by server's connection handler.
func requestHandler(
req interface{},
conn net.Conn, // Write handle to the tcp socket
quitch <-chan interface{}, // client / connection might have quit (done)
killch chan bool, // application is shutting down the server.
) {
var responses []*protobuf.ResponseStream
switch req.(type) {
case *protobuf.StatisticsRequest:
// responses = getStatistics()
case *protobuf.ScanRequest:
// responses = scanIndex()
case *protobuf.ScanAllRequest:
// responses = fullTableScan()
}
buf := make([]byte, 1024, 1024)
loop:
for _, resp := range responses {
// query storage backend for request
protobuf.EncodeAndWrite(conn, buf, resp)
select {
case <-quitch:
close(killch)
break loop
}
}
protobuf.EncodeAndWrite(conn, buf, &protobuf.StreamEndResponse{})
// Free resources.
}
func (w *protoResponseWriter) Count(c uint64) error {
res := &protobuf.CountResponse{
Count: proto.Int64(int64(c)),
}
return protobuf.EncodeAndWrite(w.conn, *w.encBuf, res)
}
func (w *protoResponseWriter) Error(err error) error {
var res interface{}
protoErr := &protobuf.Error{Error: proto.String(err.Error())}
// Drop all collected rows
w.rowEntries = nil
w.rowSize = 0
switch w.scanType {
case StatsReq:
res = &protobuf.StatisticsResponse{
Err: protoErr,
}
case CountReq:
res = &protobuf.CountResponse{
Count: proto.Int64(0), Err: protoErr,
}
case ScanAllReq, ScanReq:
res = &protobuf.ResponseStream{
Err: protoErr,
}
}
return protobuf.EncodeAndWrite(w.conn, *w.encBuf, res)
}
func (w *protoResponseWriter) Row(pk, sk []byte) error {
if w.rowSize+len(pk)+len(sk) > len(*w.rowBuf) {
res := &protobuf.ResponseStream{IndexEntries: w.rowEntries}
err := protobuf.EncodeAndWrite(w.conn, *w.encBuf, res)
if err != nil {
return err
}
w.rowSize = 0
w.rowEntries = nil
}
pkCopy := (*w.rowBuf)[w.rowSize : w.rowSize+len(pk)]
w.rowSize += len(pk)
skCopy := (*w.rowBuf)[w.rowSize : w.rowSize+len(sk)]
w.rowSize += len(sk)
copy(pkCopy, pk)
copy(skCopy, sk)
row := &protobuf.IndexEntry{
EntryKey: skCopy,
PrimaryKey: pkCopy,
}
w.rowSize += len(sk) + len(pk)
w.rowEntries = append(w.rowEntries, row)
return nil
}
func (w *protoResponseWriter) Stats(rows, unique uint64, min, max []byte) error {
res := &protobuf.StatisticsResponse{
Stats: &protobuf.IndexStatistics{
KeysCount: proto.Uint64(rows),
UniqueKeysCount: proto.Uint64(unique),
KeyMin: min,
KeyMax: max,
},
}
return protobuf.EncodeAndWrite(w.conn, *w.encBuf, res)
}
func (w *protoResponseWriter) Done() error {
defer p.PutBlock(w.encBuf)
defer p.PutBlock(w.rowBuf)
if (w.scanType == ScanReq || w.scanType == ScanAllReq) && w.rowSize > 0 {
res := &protobuf.ResponseStream{IndexEntries: w.rowEntries}
err := protobuf.EncodeAndWrite(w.conn, *w.encBuf, res)
if err != nil {
return err
}
}
return nil
}
func (s *scanCoordinator) respondWithError(conn net.Conn, req *ScanRequest, err error) {
var res interface{}
buf := p.GetBlock()
defer p.PutBlock(buf)
protoErr := &protobuf.Error{Error: proto.String(err.Error())}
switch req.ScanType {
case StatsReq:
res = &protobuf.StatisticsResponse{
Err: protoErr,
}
case CountReq:
res = &protobuf.CountResponse{
Count: proto.Int64(0), Err: protoErr,
}
case ScanAllReq, ScanReq:
res = &protobuf.ResponseStream{
Err: protoErr,
}
}
err2 := protobuf.EncodeAndWrite(conn, *buf, res)
if err2 != nil {
err = fmt.Errorf("%s, %s", err, err2)
goto finish
}
err2 = protobuf.EncodeAndWrite(conn, *buf, &protobuf.StreamEndResponse{})
if err2 != nil {
err = fmt.Errorf("%s, %s", err, err2)
}
finish:
logging.Errorf("%s RESPONSE Failed with error (%s)", req.LogPrefix, err)
}
