// Copyright 2018 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library 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 Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package stream
import (
"context"
"errors"
"fmt"
"github.com/ethereum/go-ethereum/metrics"
"github.com/ethereum/go-ethereum/p2p/enode"
"github.com/ethereum/go-ethereum/swarm/log"
"github.com/ethereum/go-ethereum/swarm/network"
"github.com/ethereum/go-ethereum/swarm/spancontext"
"github.com/ethereum/go-ethereum/swarm/storage"
opentracing "github.com/opentracing/opentracing-go"
)
const (
swarmChunkServerStreamName = "RETRIEVE_REQUEST"
deliveryCap = 32
)
var (
processReceivedChunksCount = metrics.NewRegisteredCounter("network.stream.received_chunks.count", nil)
handleRetrieveRequestMsgCount = metrics.NewRegisteredCounter("network.stream.handle_retrieve_request_msg.count", nil)
requestFromPeersCount = metrics.NewRegisteredCounter("network.stream.request_from_peers.count", nil)
requestFromPeersEachCount = metrics.NewRegisteredCounter("network.stream.request_from_peers_each.count", nil)
)
type Delivery struct {
chunkStore storage.SyncChunkStore
kad *network.Kademlia
getPeer func(enode.ID) *Peer
}
func NewDelivery(kad *network.Kademlia, chunkStore storage.SyncChunkStore) *Delivery {
return &Delivery{
chunkStore: chunkStore,
kad: kad,
}
}
// SwarmChunkServer implements Server
type SwarmChunkServer struct {
deliveryC chan []byte
batchC chan []byte
chunkStore storage.ChunkStore
currentLen uint64
quit chan struct{}
}
// NewSwarmChunkServer is SwarmChunkServer constructor
func NewSwarmChunkServer(chunkStore storage.ChunkStore) *SwarmChunkServer {
s := &SwarmChunkServer{
deliveryC: make(chan []byte, deliveryCap),
batchC: make(chan []byte),
chunkStore: chunkStore,
quit: make(chan struct{}),
}
go s.processDeliveries()
return s
}
// processDeliveries handles delivered chunk hashes
func (s *SwarmChunkServer) processDeliveries() {
var hashes []byte
var batchC chan []byte
for {
select {
case <-s.quit:
return
case hash := <-s.deliveryC:
hashes = append(hashes, hash...)
batchC = s.batchC
case batchC <- hashes:
hashes = nil
batchC = nil
}
}
}
// SessionIndex returns zero in all cases for SwarmChunkServer.
func (s *SwarmChunkServer) SessionIndex() (uint64, error) {
return 0, nil
}
// SetNextBatch
func (s *SwarmChunkServer) SetNextBatch(_, _ uint64) (hashes []byte, from uint64, to uint64, proof *HandoverProof, err error) {
select {
case hashes = <-s.batchC:
case <-s.quit:
return
}
from = s.currentLen
s.currentLen += uint64(len(hashes))
to = s.currentLen
return
}
// Close needs to be called on a stream server
func (s *SwarmChunkServer) Close() {
close(s.quit)
}
// GetData retrives chunk data from db store
func (s *SwarmChunkServer) GetData(ctx context.Context, key []byte) ([]byte, error) {
chunk, err := s.chunkStore.Get(ctx, storage.Address(key))
if err != nil {
return nil, err
}
return chunk.Data(), nil
}
// RetrieveRequestMsg is the protocol msg for chunk retrieve requests
type RetrieveRequestMsg struct {
Addr storage.Address
SkipCheck bool
HopCount uint8
}
func (d *Delivery) handleRetrieveRequestMsg(ctx context.Context, sp *Peer, req *RetrieveRequestMsg) error {
log.Trace("received request", "peer", sp.ID(), "hash", req.Addr)
handleRetrieveRequestMsgCount.Inc(1)
var osp opentracing.Span
ctx, osp = spancontext.StartSpan(
ctx,
"retrieve.request")
defer osp.Finish()
s, err := sp.getServer(NewStream(swarmChunkServerStreamName, "", true))
if err != nil {
return err
}
streamer := s.Server.(*SwarmChunkServer)
var cancel func()
// TODO: do something with this hardcoded timeout, maybe use TTL in the future
ctx = context.WithValue(ctx, "peer", sp.ID().String())
ctx = context.WithValue(ctx, "hopcount", req.HopCount)
ctx, cancel = context.WithTimeout(ctx, network.RequestTimeout)
go func() {
select {
case <-ctx.Done():
case <-streamer.quit:
}
cancel()
}()
go func() {
chunk, err := d.chunkStore.Get(ctx, req.Addr)
if err != nil {
log.Warn("ChunkStore.Get can not retrieve chunk", "peer", sp.ID().String(), "addr", req.Addr, "hopcount", req.HopCount, "err", err)
return
}
if req.SkipCheck {
syncing := false
err = sp.Deliver(ctx, chunk, s.priority, syncing)
if err != nil {
log.Warn("ERROR in handleRetrieveRequestMsg", "err", err)
}
return
}
select {
case streamer.deliveryC <- chunk.Address()[:]:
case <-streamer.quit:
}
}()
return nil
}
//Chunk delivery always uses the same message type....
type ChunkDeliveryMsg struct {
Addr storage.Address
SData []byte // the stored chunk Data (incl size)
peer *Peer // set in handleChunkDeliveryMsg
}
//...but swap accounting needs to disambiguate if it is a delivery for syncing or for retrieval
//as it decides based on message type if it needs to account for this message or not
//defines a chunk delivery for retrieval (with accounting)
type ChunkDeliveryMsgRetrieval ChunkDeliveryMsg
//defines a chunk delivery for syncing (without accounting)
type ChunkDeliveryMsgSyncing ChunkDeliveryMsg
// TODO: Fix context SNAFU
func (d *Delivery) handleChunkDeliveryMsg(ctx context.Context, sp *Peer, req *ChunkDeliveryMsg) error {
var osp opentracing.Span
ctx, osp = spancontext.StartSpan(
ctx,
"chunk.delivery")
defer osp.Finish()
processReceivedChunksCount.Inc(1)
go func() {
req.peer = sp
err := d.chunkStore.Put(ctx, storage.NewChunk(req.Addr, req.SData))
if err != nil {
if err == storage.ErrChunkInvalid {
// we removed this log because it spams the logs
// TODO: Enable this log line
// log.Warn("invalid chunk delivered", "peer", sp.ID(), "chunk", req.Addr, )
req.peer.Drop(err)
}
}
}()
return nil
}
// RequestFromPeers sends a chunk retrieve request to
func (d *Delivery) RequestFromPeers(ctx context.Context, req *network.Request) (*enode.ID, chan struct{}, error) {
requestFromPeersCount.Inc(1)
var sp *Peer
spID := req.Source
if spID != nil {
sp = d.getPeer(*spID)
if sp == nil {
return nil, nil, fmt.Errorf("source peer %v not found", spID.String())
}
} else {
d.kad.EachConn(req.Addr[:], 255, func(p *network.Peer, po int, nn bool) bool {
id := p.ID()
if p.LightNode {
// skip light nodes
return true
}
if req.SkipPeer(id.String()) {
log.Trace("Delivery.RequestFromPeers: skip peer", "peer id", id)
return true
}
sp = d.getPeer(id)
if sp == nil {
//log.Warn("Delivery.RequestFromPeers: peer not found", "id", id)
return true
}
spID = &id
return false
})
if sp == nil {
return nil, nil, errors.New("no peer found")
}
}
err := sp.SendPriority(ctx, &RetrieveRequestMsg{
Addr: req.Addr,
SkipCheck: req.SkipCheck,
HopCount: req.HopCount,
}, Top)
if err != nil {
return nil, nil, err
}
requestFromPeersEachCount.Inc(1)
return spID, sp.quit, nil
}
