cmd/torrent: Add serve subcommand

cmd/torrent/main.go

@@ -109,6 +109,7 @@ func mainErr() error {
 			fmt.Printf("Torrent version prefix: %q\n", version.DefaultBep20Prefix)
 			return nil
 		}),
+		args.Subcommand("serve", serve, args.Help("creates and seeds a torrent from a filepath")),
 	)
 	return nil
 }

cmd/torrent/serve.go

@@ -0,0 +1,72 @@
+package main
+
+import (
+	"fmt"
+	"net/http"
+	"path/filepath"
+
+	"github.com/anacrolix/args"
+	"github.com/anacrolix/log"
+	"github.com/anacrolix/torrent"
+	"github.com/anacrolix/torrent/bencode"
+	"github.com/anacrolix/torrent/metainfo"
+	"github.com/anacrolix/torrent/storage"
+)
+
+func serve(ctx args.SubCmdCtx) error {
+	var filePath string
+	ctx.Parse(args.Pos("filePath", &filePath))
+	ctx.Defer(func() error {
+		cfg := torrent.NewDefaultClientConfig()
+		cfg.Seed = true
+		cl, err := torrent.NewClient(cfg)
+		if err != nil {
+			return fmt.Errorf("new torrent client: %w", err)
+		}
+		defer cl.Close()
+		http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+			cl.WriteStatus(w)
+		})
+		info := metainfo.Info{
+			PieceLength: 1 << 18,
+		}
+		err = info.BuildFromFilePath(filePath)
+		if err != nil {
+			return fmt.Errorf("building info from path %q: %w", filePath, err)
+		}
+		for _, fi := range info.Files {
+			log.Printf("added %q", fi.Path)
+		}
+		mi := metainfo.MetaInfo{
+			InfoBytes: bencode.MustMarshal(info),
+		}
+		pc, err := storage.NewDefaultPieceCompletionForDir(".")
+		if err != nil {
+			return fmt.Errorf("new piece completion: %w", err)
+		}
+		defer pc.Close()
+		ih := mi.HashInfoBytes()
+		to, _ := cl.AddTorrentOpt(torrent.AddTorrentOpts{
+			InfoHash: ih,
+			Storage: storage.NewFileOpts(storage.NewFileClientOpts{
+				ClientBaseDir: filePath,
+				FilePathMaker: func(opts storage.FilePathMakerOpts) string {
+					return filepath.Join(opts.File.Path...)
+				},
+				TorrentDirMaker: nil,
+				PieceCompletion: pc,
+			}),
+		})
+		defer to.Drop()
+		err = to.MergeSpec(&torrent.TorrentSpec{
+			InfoBytes: mi.InfoBytes,
+			Trackers:  [][]string{{}},
+		})
+		if err != nil {
+			return fmt.Errorf("setting trackers: %w", err)
+		}
+		fmt.Println(ih)
+		select {}
+	})
+	return nil
+}