FedP2P/cmd/torrent/download.go

395 lines
11 KiB
Go

package main
import (
"context"
"expvar"
"fmt"
"io"
"net"
"net/http"
"os"
"os/signal"
"strings"
"sync"
"syscall"
"time"
"github.com/anacrolix/log"
"github.com/anacrolix/tagflag"
"github.com/davecgh/go-spew/spew"
"github.com/dustin/go-humanize"
"golang.org/x/time/rate"
"github.com/anacrolix/torrent"
"github.com/anacrolix/torrent/iplist"
"github.com/anacrolix/torrent/metainfo"
pp "github.com/anacrolix/torrent/peer_protocol"
"github.com/anacrolix/torrent/storage"
)
func torrentBar(t *torrent.Torrent, pieceStates bool) {
go func() {
start := time.Now()
if t.Info() == nil {
fmt.Printf("%v: getting torrent info for %q\n", time.Since(start), t.Name())
<-t.GotInfo()
}
lastStats := t.Stats()
var lastLine string
interval := 3 * time.Second
for range time.Tick(interval) {
var completedPieces, partialPieces int
psrs := t.PieceStateRuns()
for _, r := range psrs {
if r.Complete {
completedPieces += r.Length
}
if r.Partial {
partialPieces += r.Length
}
}
stats := t.Stats()
byteRate := int64(time.Second)
byteRate *= stats.BytesReadUsefulData.Int64() - lastStats.BytesReadUsefulData.Int64()
byteRate /= int64(interval)
line := fmt.Sprintf(
"%v: downloading %q: %s/%s, %d/%d pieces completed (%d partial): %v/s\n",
time.Since(start),
t.Name(),
humanize.Bytes(uint64(t.BytesCompleted())),
humanize.Bytes(uint64(t.Length())),
completedPieces,
t.NumPieces(),
partialPieces,
humanize.Bytes(uint64(byteRate)),
)
if line != lastLine {
lastLine = line
os.Stdout.WriteString(line)
}
if pieceStates {
fmt.Println(psrs)
}
lastStats = stats
}
}()
}
type stringAddr string
func (stringAddr) Network() string { return "" }
func (me stringAddr) String() string { return string(me) }
func resolveTestPeers(addrs []string) (ret []torrent.PeerInfo) {
for _, ta := range addrs {
ret = append(ret, torrent.PeerInfo{
Addr: stringAddr(ta),
})
}
return
}
func addTorrents(ctx context.Context, client *torrent.Client, flags downloadFlags, wg *sync.WaitGroup) error {
testPeers := resolveTestPeers(flags.TestPeer)
for _, arg := range flags.Torrent {
t, err := func() (*torrent.Torrent, error) {
if strings.HasPrefix(arg, "magnet:") {
t, err := client.AddMagnet(arg)
if err != nil {
return nil, fmt.Errorf("error adding magnet: %w", err)
}
return t, nil
} else if strings.HasPrefix(arg, "http://") || strings.HasPrefix(arg, "https://") {
response, err := http.Get(arg)
if err != nil {
return nil, fmt.Errorf("Error downloading torrent file: %s", err)
}
metaInfo, err := metainfo.Load(response.Body)
defer response.Body.Close()
if err != nil {
return nil, fmt.Errorf("error loading torrent file %q: %s\n", arg, err)
}
t, err := client.AddTorrent(metaInfo)
if err != nil {
return nil, fmt.Errorf("adding torrent: %w", err)
}
return t, nil
} else if strings.HasPrefix(arg, "infohash:") {
t, _ := client.AddTorrentInfoHash(metainfo.NewHashFromHex(strings.TrimPrefix(arg, "infohash:")))
return t, nil
} else {
metaInfo, err := metainfo.LoadFromFile(arg)
if err != nil {
return nil, fmt.Errorf("error loading torrent file %q: %s\n", arg, err)
}
t, err := client.AddTorrent(metaInfo)
if err != nil {
return nil, fmt.Errorf("adding torrent: %w", err)
}
return t, nil
}
}()
if err != nil {
return fmt.Errorf("adding torrent for %q: %w", arg, err)
}
if flags.Progress {
torrentBar(t, flags.PieceStates)
}
t.AddPeers(testPeers)
wg.Add(1)
go func() {
defer wg.Done()
select {
case <-ctx.Done():
return
case <-t.GotInfo():
}
if flags.SaveMetainfos {
path := fmt.Sprintf("%v.torrent", t.InfoHash().HexString())
err := writeMetainfoToFile(t.Metainfo(), path)
if err == nil {
log.Printf("wrote %q", path)
} else {
log.Printf("error writing %q: %v", path, err)
}
}
if len(flags.File) == 0 {
t.DownloadAll()
wg.Add(1)
go func() {
defer wg.Done()
waitForPieces(ctx, t, 0, t.NumPieces())
}()
if flags.LinearDiscard {
r := t.NewReader()
io.Copy(io.Discard, r)
r.Close()
}
} else {
for _, f := range t.Files() {
for _, fileArg := range flags.File {
if f.DisplayPath() == fileArg {
wg.Add(1)
go func() {
defer wg.Done()
waitForPieces(ctx, t, f.BeginPieceIndex(), f.EndPieceIndex())
}()
f.Download()
if flags.LinearDiscard {
r := f.NewReader()
go func() {
defer r.Close()
io.Copy(io.Discard, r)
}()
}
}
}
}
}
}()
}
return nil
}
func waitForPieces(ctx context.Context, t *torrent.Torrent, beginIndex, endIndex int) {
sub := t.SubscribePieceStateChanges()
defer sub.Close()
expected := storage.Completion{
Complete: true,
Ok: true,
}
pending := make(map[int]struct{})
for i := beginIndex; i < endIndex; i++ {
if t.Piece(i).State().Completion != expected {
pending[i] = struct{}{}
}
}
for {
if len(pending) == 0 {
return
}
select {
case ev := <-sub.Values:
if ev.Completion == expected {
delete(pending, ev.Index)
}
case <-ctx.Done():
return
}
}
}
func writeMetainfoToFile(mi metainfo.MetaInfo, path string) error {
f, err := os.OpenFile(path, os.O_CREATE|os.O_EXCL|os.O_WRONLY, 0o640)
if err != nil {
return err
}
defer f.Close()
err = mi.Write(f)
if err != nil {
return err
}
return f.Close()
}
type downloadFlags struct {
Debug bool
DownloadCmd
}
type DownloadCmd struct {
SaveMetainfos bool
Mmap bool `help:"memory-map torrent data"`
Seed bool `help:"seed after download is complete"`
Addr string `help:"network listen addr"`
MaxUnverifiedBytes *tagflag.Bytes `help:"maximum number bytes to have pending verification"`
UploadRate *tagflag.Bytes `help:"max piece bytes to send per second"`
DownloadRate *tagflag.Bytes `help:"max bytes per second down from peers"`
PackedBlocklist string
PublicIP net.IP
Progress bool `default:"true"`
PieceStates bool `help:"Output piece state runs at progress intervals."`
Quiet bool `help:"discard client logging"`
Stats bool `help:"print stats at termination"`
Dht bool `default:"true"`
PortForward bool `default:"true"`
TcpPeers bool `default:"true"`
UtpPeers bool `default:"true"`
Webtorrent bool `default:"true"`
DisableWebseeds bool
// Don't progress past handshake for peer connections where the peer doesn't offer the fast
// extension.
RequireFastExtension bool
Ipv4 bool `default:"true"`
Ipv6 bool `default:"true"`
Pex bool `default:"true"`
LinearDiscard bool `help:"Read and discard selected regions from start to finish. Useful for testing simultaneous Reader and static file prioritization."`
TestPeer []string `help:"addresses of some starting peers"`
File []string
Torrent []string `arity:"+" help:"torrent file path or magnet uri" arg:"positional"`
}
func statsEnabled(flags downloadFlags) bool {
return flags.Stats
}
func downloadErr(flags downloadFlags) error {
clientConfig := torrent.NewDefaultClientConfig()
clientConfig.DisableWebseeds = flags.DisableWebseeds
clientConfig.DisableTCP = !flags.TcpPeers
clientConfig.DisableUTP = !flags.UtpPeers
clientConfig.DisableIPv4 = !flags.Ipv4
clientConfig.DisableIPv6 = !flags.Ipv6
clientConfig.DisableAcceptRateLimiting = true
clientConfig.NoDHT = !flags.Dht
clientConfig.Debug = flags.Debug
clientConfig.Seed = flags.Seed
clientConfig.PublicIp4 = flags.PublicIP.To4()
clientConfig.PublicIp6 = flags.PublicIP
clientConfig.DisablePEX = !flags.Pex
clientConfig.DisableWebtorrent = !flags.Webtorrent
clientConfig.NoDefaultPortForwarding = !flags.PortForward
if flags.PackedBlocklist != "" {
blocklist, err := iplist.MMapPackedFile(flags.PackedBlocklist)
if err != nil {
return fmt.Errorf("loading blocklist: %v", err)
}
defer blocklist.Close()
clientConfig.IPBlocklist = blocklist
}
if flags.Mmap {
clientConfig.DefaultStorage = storage.NewMMap("")
}
if flags.Addr != "" {
clientConfig.SetListenAddr(flags.Addr)
}
if flags.UploadRate != nil {
// TODO: I think the upload rate limit could be much lower.
clientConfig.UploadRateLimiter = rate.NewLimiter(rate.Limit(*flags.UploadRate), 256<<10)
}
if flags.DownloadRate != nil {
clientConfig.DownloadRateLimiter = rate.NewLimiter(rate.Limit(*flags.DownloadRate), 1<<16)
}
{
logger := log.Default.WithNames("main", "client")
if flags.Quiet {
logger = logger.FilterLevel(log.Critical)
}
clientConfig.Logger = logger
}
if flags.RequireFastExtension {
clientConfig.MinPeerExtensions.SetBit(pp.ExtensionBitFast, true)
}
if flags.MaxUnverifiedBytes != nil {
clientConfig.MaxUnverifiedBytes = flags.MaxUnverifiedBytes.Int64()
}
ctx, cancel := signal.NotifyContext(context.Background(), os.Interrupt, syscall.SIGTERM)
defer cancel()
client, err := torrent.NewClient(clientConfig)
if err != nil {
return fmt.Errorf("creating client: %w", err)
}
defer client.Close()
// Write status on the root path on the default HTTP muxer. This will be bound to localhost
// somewhere if GOPPROF is set, thanks to the envpprof import.
http.HandleFunc("/", func(w http.ResponseWriter, req *http.Request) {
client.WriteStatus(w)
})
var wg sync.WaitGroup
err = addTorrents(ctx, client, flags, &wg)
if err != nil {
return fmt.Errorf("adding torrents: %w", err)
}
started := time.Now()
defer outputStats(client, flags)
wg.Wait()
if ctx.Err() == nil {
log.Print("downloaded ALL the torrents")
} else {
err = ctx.Err()
}
clientConnStats := client.ConnStats()
log.Printf("average download rate: %v",
humanize.Bytes(uint64(
time.Duration(
clientConnStats.BytesReadUsefulData.Int64(),
)*time.Second/time.Since(started),
)))
if flags.Seed {
if len(client.Torrents()) == 0 {
log.Print("no torrents to seed")
} else {
outputStats(client, flags)
<-ctx.Done()
}
}
spew.Dump(expvar.Get("torrent").(*expvar.Map).Get("chunks received"))
spew.Dump(client.ConnStats())
clStats := client.ConnStats()
sentOverhead := clStats.BytesWritten.Int64() - clStats.BytesWrittenData.Int64()
log.Printf(
"client read %v, %.1f%% was useful data. sent %v non-data bytes",
humanize.Bytes(uint64(clStats.BytesRead.Int64())),
100*float64(clStats.BytesReadUsefulData.Int64())/float64(clStats.BytesRead.Int64()),
humanize.Bytes(uint64(sentOverhead)))
return err
}
func outputStats(cl *torrent.Client, args downloadFlags) {
if !statsEnabled(args) {
return
}
expvar.Do(func(kv expvar.KeyValue) {
fmt.Printf("%s: %s\n", kv.Key, kv.Value)
})
cl.WriteStatus(os.Stdout)
}