mirror of
				https://github.com/minio/minio.git
				synced 2025-11-04 10:11:09 +01:00 
			
		
		
		
	
		
			
				
	
	
		
			115 lines
		
	
	
		
			3.1 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			115 lines
		
	
	
		
			3.1 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
// Copyright (c) 2015-2023 MinIO, Inc.
 | 
						|
//
 | 
						|
// This file is part of MinIO Object Storage stack
 | 
						|
//
 | 
						|
// This program is free software: you can redistribute it and/or modify
 | 
						|
// it under the terms of the GNU Affero General Public License as published by
 | 
						|
// the Free Software Foundation, either version 3 of the License, or
 | 
						|
// (at your option) any later version.
 | 
						|
//
 | 
						|
// This program is distributed in the hope that it will be useful
 | 
						|
// but WITHOUT ANY WARRANTY; without even the implied warranty of
 | 
						|
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 | 
						|
// GNU Affero General Public License for more details.
 | 
						|
//
 | 
						|
// You should have received a copy of the GNU Affero General Public License
 | 
						|
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
 | 
						|
 | 
						|
package grid
 | 
						|
 | 
						|
import (
 | 
						|
	"context"
 | 
						|
	"errors"
 | 
						|
)
 | 
						|
 | 
						|
// A Stream is a two-way stream.
 | 
						|
// All responses *must* be read by the caller.
 | 
						|
// If the call is canceled through the context,
 | 
						|
// the appropriate error will be returned.
 | 
						|
type Stream struct {
 | 
						|
	// responses from the remote server.
 | 
						|
	// Channel will be closed after error or when remote closes.
 | 
						|
	// All responses *must* be read by the caller until either an error is returned or the channel is closed.
 | 
						|
	// Canceling the context will cause the context cancellation error to be returned.
 | 
						|
	responses <-chan Response
 | 
						|
	cancel    context.CancelCauseFunc
 | 
						|
 | 
						|
	// Requests sent to the server.
 | 
						|
	// If the handler is defined with 0 incoming capacity this will be nil.
 | 
						|
	// Channel *must* be closed to signal the end of the stream.
 | 
						|
	// If the request context is canceled, the stream will no longer process requests.
 | 
						|
	// Requests sent cannot be used any further by the called.
 | 
						|
	Requests chan<- []byte
 | 
						|
 | 
						|
	muxID uint64
 | 
						|
	ctx   context.Context
 | 
						|
}
 | 
						|
 | 
						|
// Send a payload to the remote server.
 | 
						|
func (s *Stream) Send(b []byte) error {
 | 
						|
	if s.Requests == nil {
 | 
						|
		return errors.New("stream does not accept requests")
 | 
						|
	}
 | 
						|
	select {
 | 
						|
	case s.Requests <- b:
 | 
						|
		return nil
 | 
						|
	case <-s.ctx.Done():
 | 
						|
		return context.Cause(s.ctx)
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
// Results returns the results from the remote server one by one.
 | 
						|
// If any error is returned by the callback, the stream will be canceled.
 | 
						|
// If the context is canceled, the stream will be canceled.
 | 
						|
func (s *Stream) Results(next func(b []byte) error) (err error) {
 | 
						|
	done := false
 | 
						|
	defer func() {
 | 
						|
		if s.cancel != nil {
 | 
						|
			s.cancel(err)
 | 
						|
		}
 | 
						|
 | 
						|
		if !done {
 | 
						|
			// Drain channel.
 | 
						|
			for range s.responses {
 | 
						|
			}
 | 
						|
		}
 | 
						|
	}()
 | 
						|
	doneCh := s.ctx.Done()
 | 
						|
	for {
 | 
						|
		select {
 | 
						|
		case <-doneCh:
 | 
						|
			if err := context.Cause(s.ctx); !errors.Is(err, errStreamEOF) {
 | 
						|
				return err
 | 
						|
			}
 | 
						|
			// Fall through to be sure we have returned all responses.
 | 
						|
			doneCh = nil
 | 
						|
		case resp, ok := <-s.responses:
 | 
						|
			if !ok {
 | 
						|
				done = true
 | 
						|
				return nil
 | 
						|
			}
 | 
						|
			if resp.Err != nil {
 | 
						|
				s.cancel(resp.Err)
 | 
						|
				return resp.Err
 | 
						|
			}
 | 
						|
			err = next(resp.Msg)
 | 
						|
			if err != nil {
 | 
						|
				s.cancel(err)
 | 
						|
				return err
 | 
						|
			}
 | 
						|
		}
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
// Done will return a channel that will be closed when the stream is done.
 | 
						|
// This mirrors context.Done().
 | 
						|
func (s *Stream) Done() <-chan struct{} {
 | 
						|
	return s.ctx.Done()
 | 
						|
}
 | 
						|
 | 
						|
// Err will return the error that caused the stream to end.
 | 
						|
// This mirrors context.Err().
 | 
						|
func (s *Stream) Err() error {
 | 
						|
	return s.ctx.Err()
 | 
						|
}
 |