chunk_stream.go

// Copyright 2021 The Swarm Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package api

import (
	"context"
	"errors"
	"net/http"
	"strconv"
	"time"

	"github.com/ethersphere/bee/v2/pkg/cac"
	"github.com/ethersphere/bee/v2/pkg/jsonhttp"
	"github.com/ethersphere/bee/v2/pkg/log"
	"github.com/ethersphere/bee/v2/pkg/postage"
	"github.com/ethersphere/bee/v2/pkg/storage"
	"github.com/ethersphere/bee/v2/pkg/storer"
	"github.com/ethersphere/bee/v2/pkg/swarm"
	"github.com/gorilla/websocket"
)

const streamReadTimeout = 15 * time.Minute

var successWsMsg = []byte{}

func (s *Service) chunkUploadStreamHandler(w http.ResponseWriter, r *http.Request) {
	logger := s.logger.WithName("chunks_stream").Build()

	headers := struct {
		BatchID  []byte `map:"Swarm-Postage-Batch-Id"` // Optional: omit if caller provides pre-signed stamps per chunk
		SwarmTag uint64 `map:"Swarm-Tag"`
	}{}
	if response := s.mapStructure(r.Header, &headers); response != nil {
		response("invalid header params", logger, w)
		return
	}

	// Fallback: read tag from query parameter (browser WebSocket can't set headers)
	if headers.SwarmTag == 0 {
		if qTag := r.URL.Query().Get("swarm-tag"); qTag != "" {
			parsed, err := strconv.ParseUint(qTag, 10, 64)
			if err != nil {
				logger.Debug("invalid swarm-tag query parameter", "value", qTag, "error", err)
				jsonhttp.BadRequest(w, "invalid swarm-tag query parameter")
				return
			}
			headers.SwarmTag = parsed
		}
	}

	var (
		tag uint64
		err error
	)
	if headers.SwarmTag > 0 {
		tag, err = s.getOrCreateSessionID(headers.SwarmTag)
		if err != nil {
			logger.Debug("get or create tag failed", "error", err)
			logger.Error(nil, "get or create tag failed")
			switch {
			case errors.Is(err, storage.ErrNotFound):
				jsonhttp.NotFound(w, "tag not found")
			default:
				jsonhttp.InternalServerError(w, "cannot get or create tag")
			}
			return
		}
	}

	// Create connection-level putter only if BatchID is provided.
	// If BatchID is not provided, the API caller is expected to provide
	// pre-signed stamps with each chunk (and is also expected to keep
	// track of stamp state over time).
	var putter storer.PutterSession
	if len(headers.BatchID) > 0 {
		// if tag not specified use direct upload
		// Using context.Background here because the putter's lifetime extends beyond that of the HTTP request.
		putter, err = s.newStamperPutter(context.Background(), putterOptions{
			BatchID:  headers.BatchID,
			TagID:    tag,
			Deferred: tag != 0,
		})
		if err != nil {
			logger.Debug("get putter failed", "error", err)
			logger.Error(nil, "get putter failed")
			switch {
			case errors.Is(err, errBatchUnusable) || errors.Is(err, postage.ErrNotUsable):
				jsonhttp.UnprocessableEntity(w, "batch not usable yet or does not exist")
			case errors.Is(err, postage.ErrNotFound):
				jsonhttp.NotFound(w, "batch with id not found")
			case errors.Is(err, errInvalidPostageBatch):
				jsonhttp.BadRequest(w, "invalid batch id")
			case errors.Is(err, errUnsupportedDevNodeOperation):
				jsonhttp.BadRequest(w, errUnsupportedDevNodeOperation)
			default:
				jsonhttp.BadRequest(w, nil)
			}
			return
		}
	}

	upgrader := websocket.Upgrader{
		ReadBufferSize:  swarm.SocMaxChunkSize,
		WriteBufferSize: swarm.SocMaxChunkSize,
		CheckOrigin:     s.checkOrigin,
	}

	wsConn, err := upgrader.Upgrade(w, r, nil)
	if err != nil {
		logger.Debug("chunk upload: upgrade failed", "error", err)
		logger.Error(nil, "chunk upload: upgrade failed")
		jsonhttp.BadRequest(w, "upgrade failed")
		return
	}

	s.wsWg.Add(1)
	var decode chunkDecoder
	if len(headers.BatchID) > 0 {
		decode = decodeChunkWithoutStamp
	} else {
		decode = decodeChunkWithStamp
	}
	go s.handleUploadStream(logger, wsConn, putter, tag, decode)
}

// chunkDecoder extracts chunk data and optionally a stamp from a websocket message.
// When BatchID is provided in headers, decodeChunkWithoutStamp is used (no stamp in message).
// When BatchID is not provided, decodeChunkWithStamp is used (stamp prepended to chunk data).
type chunkDecoder func(msg []byte) (chunkData []byte, stamp *postage.Stamp, err error)

// decodeChunkWithoutStamp returns the message as-is (used when BatchID provided in headers).
func decodeChunkWithoutStamp(msg []byte) ([]byte, *postage.Stamp, error) {
	return msg, nil, nil
}

// decodeChunkWithStamp extracts a stamp from the first 113 bytes of the message.
// Returns an error if the message is too small or the stamp is invalid.
func decodeChunkWithStamp(msg []byte) ([]byte, *postage.Stamp, error) {
	if len(msg) < postage.StampSize+swarm.SpanSize {
		return nil, nil, errors.New("message too small for stamp + chunk")
	}

	stamp := &postage.Stamp{}
	if err := stamp.UnmarshalBinary(msg[:postage.StampSize]); err != nil {
		return nil, nil, errors.New("invalid stamp")
	}

	return msg[postage.StampSize:], stamp, nil
}

func (s *Service) handleUploadStream(
	logger log.Logger,
	conn *websocket.Conn,
	putter storer.PutterSession,
	tag uint64,
	decode chunkDecoder,
) {
	defer s.wsWg.Done()

	ctx, cancel := context.WithCancel(context.Background())

	var (
		gone = make(chan struct{})
		err  error
	)

	// Cache for batch validation to avoid database lookups for every chunk
	// Key: batch ID hex string, Value: stored batch info
	// This avoids the expensive batchStore.Get() call for each chunk
	batchCache := make(map[string]*postage.Batch)

	defer func() {
		cancel()
		_ = conn.Close()

		// No cleanup needed for batch cache - it's just metadata

		// Only call Done on connection-level putter if it exists
		if putter != nil {
			if err = putter.Done(swarm.ZeroAddress); err != nil {
				logger.Error(err, "chunk upload stream: syncing chunks failed")
			}
		}
	}()

	conn.SetCloseHandler(func(code int, text string) error {
		logger.Debug("chunk upload stream: client gone", "code", code, "message", text)
		close(gone)
		return nil
	})

	sendMsg := func(msgType int, buf []byte) error {
		err := conn.SetWriteDeadline(time.Now().Add(writeDeadline))
		if err != nil {
			return err
		}
		err = conn.WriteMessage(msgType, buf)
		if err != nil {
			return err
		}
		return nil
	}

	sendErrorClose := func(code int, errmsg string) {
		err := conn.WriteControl(
			websocket.CloseMessage,
			websocket.FormatCloseMessage(code, errmsg),
			time.Now().Add(writeDeadline),
		)
		if err != nil {
			logger.Error(err, "chunk upload stream: failed sending close message")
		}
	}

	for {
		select {
		case <-s.quit:
			// shutdown
			sendErrorClose(websocket.CloseGoingAway, "node shutting down")
			return
		case <-gone:
			// client gone
			return
		default:
			// if there is no indication to stop, go ahead and read the next message
		}

		err = conn.SetReadDeadline(time.Now().Add(streamReadTimeout))
		if err != nil {
			logger.Debug("chunk upload stream: set read deadline failed", "error", err)
			logger.Error(nil, "chunk upload stream: set read deadline failed")
			return
		}

		mt, msg, err := conn.ReadMessage()
		if err != nil {
			if websocket.IsUnexpectedCloseError(err, websocket.CloseGoingAway, websocket.CloseAbnormalClosure) {
				logger.Debug("chunk upload stream: read message failed", "error", err)
				logger.Error(nil, "chunk upload stream: read message failed")
			}
			return
		}

		if mt != websocket.BinaryMessage {
			logger.Debug("chunk upload stream: unexpected message received from client", "message_type", mt)
			logger.Error(nil, "chunk upload stream: unexpected message received from client")
			sendErrorClose(websocket.CloseUnsupportedData, "invalid message")
			return
		}

		if len(msg) < swarm.SpanSize {
			logger.Debug("chunk upload stream: insufficient data")
			logger.Error(nil, "chunk upload stream: insufficient data")
			return
		}

		// Decode the message using the appropriate decoder
		chunkData, stamp, err := decode(msg)
		if err != nil {
			logger.Debug("chunk upload stream: decode failed", "error", err)
			logger.Error(nil, "chunk upload stream: "+err.Error())
			sendErrorClose(websocket.CloseInternalServerErr, err.Error())
			return
		}

		// Determine the putter to use
		var (
			chunk       swarm.Chunk
			chunkPutter = putter
		)

		// If stamp was extracted, create a per-chunk putter
		if stamp != nil {
			batchID := stamp.BatchID()
			batchIDKey := string(batchID)

			storedBatch, exists := batchCache[batchIDKey]
			if !exists {
				storedBatch, err = s.batchStore.Get(batchID)
				if err != nil {
					logger.Debug("chunk upload stream: batch validation failed", "error", err)
					logger.Error(nil, "chunk upload stream: batch validation failed")
					if errors.Is(err, storage.ErrNotFound) {
						sendErrorClose(websocket.CloseInternalServerErr, "batch not found")
					} else {
						sendErrorClose(websocket.CloseInternalServerErr, "batch validation failed")
					}
					return
				}
				batchCache[batchIDKey] = storedBatch
			}

			chunkPutter, err = s.newStampedPutterWithBatch(ctx, putterOptions{
				BatchID:  batchID,
				TagID:    tag,
				Deferred: tag != 0,
			}, stamp, storedBatch)
			if err != nil {
				logger.Debug("chunk upload stream: failed to create stamped putter", "error", err)
				logger.Error(nil, "chunk upload stream: failed to create stamped putter")
				switch {
				case errors.Is(err, errBatchUnusable) || errors.Is(err, postage.ErrNotUsable):
					sendErrorClose(websocket.CloseInternalServerErr, "batch not usable")
				case errors.Is(err, postage.ErrNotFound):
					sendErrorClose(websocket.CloseInternalServerErr, "batch not found")
				default:
					sendErrorClose(websocket.CloseInternalServerErr, "stamped putter creation failed")
				}
				return
			}
		}

		chunk, err = cac.NewWithDataSpan(chunkData)
		if err != nil {
			logger.Debug("chunk upload stream: create chunk failed", "error", err, "chunk_size", len(chunkData))
			logger.Error(nil, "chunk upload stream: create chunk failed")
			if chunkPutter != putter {
				_ = chunkPutter.Cleanup()
			}
			sendErrorClose(websocket.CloseInternalServerErr, "invalid chunk data")
			return
		}

		err = chunkPutter.Put(ctx, chunk)
		if err != nil {
			logger.Debug("chunk upload stream: write chunk failed", "address", chunk.Address(), "error", err)
			logger.Error(nil, "chunk upload stream: write chunk failed")
			if chunkPutter != putter {
				_ = chunkPutter.Cleanup()
			}
			switch {
			case errors.Is(err, postage.ErrBucketFull):
				sendErrorClose(websocket.CloseInternalServerErr, "batch is overissued")
			default:
				sendErrorClose(websocket.CloseInternalServerErr, "chunk write error")
			}
			return
		}

		// Clean up per-chunk putter
		if chunkPutter != putter {
			if err := chunkPutter.Done(swarm.ZeroAddress); err != nil {
				logger.Error(err, "chunk upload stream: failed to finalize per-chunk putter")
			}
		}

		err = sendMsg(websocket.BinaryMessage, successWsMsg)
		if err != nil {
			s.logger.Debug("chunk upload stream: sending success message failed", "error", err)
			s.logger.Error(nil, "chunk upload stream: sending success message failed")
			return
		}
	}
}