// Fetch sends given fetch request to kafka node and returns related response.
// Calling this method on closed connection will always return ErrClosed.
func (c *connection) Fetch(req *proto.FetchReq) (*proto.FetchResp, error) {
var ok bool
if req.CorrelationID, ok = <-c.nextID; !ok {
return nil, c.stopErr
}
if _, err := req.WriteTo(c.conn); err != nil {
return nil, err
}
b, ok := <-c.respc[req.CorrelationID]
if !ok {
return nil, c.stopErr
}
return proto.ReadFetchResp(bytes.NewReader(b))
}
// Fetch sends given fetch request to kafka node and returns related response.
// Calling this method on closed connection will always return ErrClosed.
func (c *connection) Fetch(req *proto.FetchReq) (*proto.FetchResp, error) {
var ok bool
if req.CorrelationID, ok = <-c.nextID; !ok {
return nil, c.stopErr
}
respc, err := c.respWaiter(req.CorrelationID)
if err != nil {
c.logger.Error("msg", "failed waiting for response", "error", err)
return nil, fmt.Errorf("wait for response: %s", err)
}
if _, err := req.WriteTo(c.rw); err != nil {
c.logger.Error("msg", "cannot write", "error", err)
c.releaseWaiter(req.CorrelationID)
return nil, err
}
b, ok := <-respc
if !ok {
return nil, c.stopErr
}
resp, err := proto.ReadFetchResp(bytes.NewReader(b))
if err != nil {
return nil, err
}
// Compressed messages are returned in full batches for efficiency
// (the broker doesn't need to decompress).
// This means that it's possible to get some leading messages
// with a smaller offset than requested. Trim those.
for ti := range resp.Topics {
topic := &resp.Topics[ti]
reqTopic := &req.Topics[ti]
for pi := range topic.Partitions {
partition := &topic.Partitions[pi]
reqPartition := &reqTopic.Partitions[pi]
i := 0
for _, msg := range partition.Messages {
if msg.Offset >= reqPartition.FetchOffset {
break
}
i++
}
partition.Messages = partition.Messages[i:]
}
}
return resp, nil
}
// Fetch sends given fetch request to kafka node and returns related response.
// Calling this method on closed connection will always return ErrClosed.
func (c *connection) Fetch(req *proto.FetchReq) (*proto.FetchResp, error) {
var ok bool
if req.CorrelationID, ok = <-c.nextID; !ok {
return nil, c.stopErr
}
respc, err := c.respWaiter(req.CorrelationID)
if err != nil {
return nil, fmt.Errorf("wait for response: %s", err)
}
if _, err := req.WriteTo(c.rw); err != nil {
c.releaseWaiter(req.CorrelationID)
return nil, err
}
b, ok := <-respc
if !ok {
return nil, c.stopErr
}
return proto.ReadFetchResp(bytes.NewReader(b))
}