it works

.gitignore

@@ -13,3 +13,5 @@
 
 # Dependency directories (remove the comment below to include it)
 # vendor/
+#
+*.torrent.db*

README.md

@@ -1,2 +1,93 @@
-# p2pfile
-p2pfile - DHT-based P2P file distribution command line tools.
+# p2pfile - DHT-based P2P file distribution command line tools
+
+## 背景
+
+### 应用场景
+
+- 所有节点网络联通的环境下的文件分布式分发。
+- 私有网络环境，和互联网隔离。
+- 无文件加密传输需求
+
+### 设计限制
+
+- 不支持 Tracker，只支持 DHT 网络，从而简化设计。
+- 不需要 Daemon 常驻进程，只需要单个二进制文件。
+- 无加密设计
+- 只支持单个文件分发，不支持文件夹分发。
+- 不支持 IPv6。
+
+### 设计目标
+
+- 提供私有网络环境下的文件分布式分发。
+- 提供最简化的使用方法，一条命令。
+
+## 命令行设计
+
+```txt
+DHT-based P2P file distribution command line tools. For example:
+
+p2pfile serve <FILE_PATH1> <FILE_PATH2> ...
+p2pfile download <MAGNET_URI> <MAGNET_URI2> ...
+
+Usage:
+  p2pfile [command]
+
+Available Commands:
+  completion  Generate the autocompletion script for the specified shell
+  download    Download file from magnet uri.
+  help        Help about any command
+  serve       creates and seeds a torrent from filepaths.
+
+Flags:
+      --config string          config file (default is $HOME/.p2pfile.yaml)
+      --ip string              Set ip. (default: default route ip)
+      --port int               Set port. (default: random port in port-range,  See --port-range)
+      --port-range string      Set random port range. (default: 42070-42099) (default "42070-42099")
+      --peers strings          Set bootstrap peers. (default: empty) (eg: --peers 10.1.1.1:2233,10.2.2.2:4567
+      --upload-limit float     Set upload limit, MiB. (default: 0.0)
+      --download-limit float   Set download limit, MiB. (default: 0.0)
+      --debug                  Debug mode.
+  -h, --help                   help for p2pfile
+
+Use "p2pfile [command] --help" for more information about a command.
+```
+
+## 其他设计
+
+A. Magnet URI schema（使用了[BEP0009](http://www.bittorrent.org/beps/bep_0009.html) 扩展）
+
+`magnet:?xt=urn:btih:<info-hash>&dn=<name>&x.pe=<peer-address>`
+
+- `info-hash`: 哈希值，用于标识文件
+- `name`: 文件名[可选]
+- `peer-address`: 做种机器的Peer地址，用于初始化 DHT 网络
+
+一台机器并发做种或者下载：
+
+- 由于无后台进程，每个进程都是单独的客户端，均需要占用一个端口。
+- 故端口需要支持随机分配，从而避免端口冲突。
+    - 随机分配方法：在端口段中随机选择端口，如果端口被占用，则重新随机选择。
+- 随机分配存在当做种进程重启后，其新的端口号和之前不同。
+    - 方法1：将端口号持久化，当重新serve的时候，使用之前的端口号
+    - 方法2：重新做种的时候，需要传入magnet uri，从中解析出端口号。
+
+B. 做种高可用性：
+
+- 可以使用2+台机器同时做种，做种时增加参数：`--peers=<peer1>,<peer2>` 从而保证Magnet URI的高可用性。
+
+C. 下载后持续做种：
+
+- 增加参数 `--seeding`，指定下载之后持续做种。持续做种结束条件有多个，任意条件满足即停止做种。
+    - `--seeding-time=<time>`，指定持续做种的时间，单位为秒。默认为 60s。
+    - `--seeding-ratio=<ratio>`，指定持续做种的种子分享率，单位为百分比。默认为 1.0。
+- 该参数推荐在大文件分发时使用，小文件分发没必要且不建议使用。
+
+D. 信息存储：
+
+- 默认为 SQlite，会在当前目录下生成 `.*db.*` 文件。
+- (后续支持) 支持更换存储后端，比如 bolt/sqlite/file etc.
+
+E. 库：
+
+- <https://github.com/anacrolix/torrent>: 主要使用.
+- <https://gitlab.com/axet/libtorrent>: 后续参考实现 14: Local Peers Discovery / 19: WebSeeds.

cmd/download.go

@@ -0,0 +1,63 @@
+package cmd
+
+import (
+	"context"
+	"os"
+	"os/signal"
+
+	"github.com/spf13/cobra"
+	"github.com/spf13/viper"
+
+	"github.com/ninehills/p2pfile/pkg/libtorrent"
+
+	log "github.com/sirupsen/logrus"
+)
+
+func newDownloadCmd() *cobra.Command {
+	var downloadCmd = &cobra.Command{
+		Use:   "download",
+		Short: "Download file from magnet uri.",
+		Long: `Download file from magnet uri. Usage:
+
+p2pfile download <MAGNET_URI> <MAGNET_URI2> ...`,
+		Args: cobra.MinimumNArgs(1),
+		Run: func(cmd *cobra.Command, args []string) {
+			// TODO: 写入这里才生效，需要改进
+			initLogger(viper.GetBool("debug"))
+			// TODO: support set download directory
+			downloader, err := libtorrent.NewTorrentServer(
+				"download", viper.GetString("ip"), viper.GetInt("port"), viper.GetString("port-range"),
+				viper.GetStringSlice("peers"), viper.GetFloat64("upload-limit"),
+				viper.GetFloat64("download-limit"), viper.GetBool("debug"),
+				args, []string{},
+			)
+			if err != nil {
+				log.Fatal("Failed to create downloader: ", err)
+			}
+			ctx := context.Background()
+
+			// trap Ctrl+C and call cancel on the context
+			ctx, cancel := context.WithCancel(ctx)
+			c := make(chan os.Signal, 1)
+			signal.Notify(c, os.Interrupt)
+			defer func() {
+				signal.Stop(c)
+				cancel()
+			}()
+			go func() {
+				select {
+				case sig := <-c:
+					log.Errorf("Caught signal %v, shutting down...\n", sig)
+					cancel()
+				case <-ctx.Done():
+				}
+			}()
+			err = downloader.RunDownloader(ctx)
+			if err != nil {
+				log.Fatal("Failed to run downloader: ", err)
+			}
+		},
+	}
+	downloadCmd.MarkFlagRequired("magnet")
+	return downloadCmd
+}

cmd/root.go

@@ -0,0 +1,99 @@
+package cmd
+
+import (
+	"fmt"
+	"os"
+
+	log "github.com/sirupsen/logrus"
+	"github.com/spf13/cobra"
+	"github.com/spf13/viper"
+)
+
+var cfgFile string
+
+// rootCmd represents the base command when called without any subcommands
+var rootCmd = &cobra.Command{
+	Use:   "p2pfile",
+	Short: "DHT-based P2P file distribution command line tools",
+	Long: `DHT-based P2P file distribution command line tools. For example:
+
+p2pfile serve <FILE_PATH1> <FILE_PATH2> ...
+p2pfile download <MAGNET_URI> <MAGNET_URI2> ...`,
+	// Uncomment the following line if your bare application
+	// has an action associated with it:
+	// Run: func(cmd *cobra.Command, args []string) { },
+}
+
+// Execute adds all child commands to the root command and sets flags appropriately.
+// This is called by main.main(). It only needs to happen once to the rootCmd.
+func Execute() {
+	err := rootCmd.Execute()
+	if err != nil {
+		os.Exit(1)
+	}
+}
+
+func init() {
+	cobra.OnInitialize(initConfig)
+
+	rootCmd.Flags().SortFlags = false
+	rootCmd.PersistentFlags().SortFlags = false
+
+	rootCmd.PersistentFlags().StringVar(&cfgFile, "config", "", "config file (default is $HOME/.p2pfile.yaml)")
+	rootCmd.PersistentFlags().String("ip", "", "Set ip. (default: default route ip)")
+	rootCmd.PersistentFlags().Int("port", 0, "Set port. (default: random port in port-range,  See --port-range)")
+	rootCmd.PersistentFlags().String("port-range", "42070-42099", "Set random port range. (default: 42070-42099)")
+	rootCmd.PersistentFlags().StringSlice("peers", []string{}, "Set bootstrap peers. (default: empty) (eg: --peers 10.1.1.1:2233,10.2.2.2:4567")
+	rootCmd.PersistentFlags().Float64("upload-limit", 0.0, "Set upload limit, MiB. (default: 0.0)")
+	rootCmd.PersistentFlags().Float64("download-limit", 0.0, "Set download limit, MiB. (default: 0.0)")
+	rootCmd.PersistentFlags().Bool("debug", false, "Debug mode.")
+
+	viper.BindPFlag("ip", rootCmd.PersistentFlags().Lookup("ip"))
+	viper.BindPFlag("port", rootCmd.PersistentFlags().Lookup("port"))
+	viper.BindPFlag("port-range", rootCmd.PersistentFlags().Lookup("port-range"))
+	viper.BindPFlag("peers", rootCmd.PersistentFlags().Lookup("peers"))
+	viper.BindPFlag("upload-limit", rootCmd.PersistentFlags().Lookup("upload-limit"))
+	viper.BindPFlag("download-limit", rootCmd.PersistentFlags().Lookup("download-limit"))
+	viper.BindPFlag("debug", rootCmd.PersistentFlags().Lookup("debug"))
+
+	rootCmd.AddCommand(newServeCmd())
+	rootCmd.AddCommand(newDownloadCmd())
+}
+
+func initConfig() {
+	if cfgFile != "" {
+		// Use config file from the flag.
+		viper.SetConfigFile(cfgFile)
+	} else {
+		// Find home directory.
+		home, err := os.UserHomeDir()
+		cobra.CheckErr(err)
+
+		// Search config in home directory with name ".cobra" (without extension).
+		viper.AddConfigPath(home)
+		viper.SetConfigType("yaml")
+		viper.SetConfigName(".p2pfile")
+	}
+
+	viper.AutomaticEnv()
+
+	if err := viper.ReadInConfig(); err == nil {
+		fmt.Println("Using config file:", viper.ConfigFileUsed())
+	}
+}
+
+func initLogger(debug bool) {
+	// Log as JSON instead of the default ASCII formatter.
+	// log.SetFormatter(&log.JSONFormatter{})
+
+	// Output to stdout instead of the default stderr
+	// Can be any io.Writer, see below for File example
+	log.SetOutput(os.Stdout)
+
+	if debug {
+		log.Infof("Logging level set to debug.")
+		log.SetLevel(log.DebugLevel)
+	} else {
+		log.SetLevel(log.InfoLevel)
+	}
+}

cmd/serve.go

@@ -0,0 +1,60 @@
+package cmd
+
+import (
+	"context"
+	"os"
+	"os/signal"
+
+	"github.com/ninehills/p2pfile/pkg/libtorrent"
+	log "github.com/sirupsen/logrus"
+	"github.com/spf13/cobra"
+	"github.com/spf13/viper"
+)
+
+func newServeCmd() *cobra.Command {
+	var serveCmd = &cobra.Command{
+		Use:   "serve",
+		Short: "creates and seeds a torrent from filepaths.",
+		Long: `DHT-based P2P file distribution command line tools. Usage:
+
+p2pfile serve <FILE_PATH1> <FILE_PATH2> ...`,
+		Run: func(cmd *cobra.Command, args []string) {
+			// TODO: 写入这里才生效，需要改进
+			initLogger(viper.GetBool("debug"))
+			server, err := libtorrent.NewTorrentServer(
+				"serve", viper.GetString("ip"), viper.GetInt("port"), viper.GetString("port-range"),
+				viper.GetStringSlice("peers"), viper.GetFloat64("upload-limit"),
+				viper.GetFloat64("download-limit"), viper.GetBool("debug"),
+				[]string{}, args,
+			)
+			if err != nil {
+				log.Fatal("Failed to create server: ", err)
+			}
+
+			ctx := context.Background()
+
+			// trap Ctrl+C and call cancel on the context
+			ctx, cancel := context.WithCancel(ctx)
+			c := make(chan os.Signal, 1)
+			signal.Notify(c, os.Interrupt)
+			defer func() {
+				signal.Stop(c)
+				cancel()
+			}()
+			go func() {
+				select {
+				case sig := <-c:
+					log.Errorf("Caught signal %v, shutting down...\n", sig)
+					cancel()
+				case <-ctx.Done():
+				}
+			}()
+			err = server.RunServer(ctx)
+			if err != nil {
+				log.Fatal("Failed to run server: ", err)
+			}
+		},
+	}
+	serveCmd.MarkFlagRequired("files")
+	return serveCmd
+}