seaweedfs/weed-fs/src/cmd/weed/volume.go

package main

import (
  "log"
  "math/rand"
  "mime"
  "net/http"
  "pkg/storage"
  "strconv"
  "strings"
  "time"
)

func init() {
  cmdVolume.Run = runVolume // break init cycle
  IsDebug     = cmdVolume.Flag.Bool("debug", false, "enable debug mode")
  port        = cmdVolume.Flag.Int("port", 8080, "http listen port")
}

var cmdVolume = &Command{
  UsageLine: "volume -port=8080 -dir=/tmp -volumes=0-99 -publicUrl=server_name:8080 -mserver=localhost:9333",
  Short:     "start a volume server",
  Long: `start a volume server to provide storage spaces

  `,
}

var (
  chunkFolder = cmdVolume.Flag.String("dir", "/tmp", "data directory to store files")
  volumes     = cmdVolume.Flag.String("volumes", "0,1-3,4", "comma-separated list of volume ids or range of ids")
  publicUrl   = cmdVolume.Flag.String("publicUrl", "localhost:8080", "public url to serve data read")
  metaServer  = cmdVolume.Flag.String("mserver", "localhost:9333", "master directory server to store mappings")
  pulse       = cmdVolume.Flag.Int("pulseSeconds", 5, "number of seconds between heartbeats")

  store *storage.Store

)

func statusHandler(w http.ResponseWriter, r *http.Request) {
  writeJson(w, r, store.Status())
}
func addVolumeHandler(w http.ResponseWriter, r *http.Request) {
  store.AddVolume(r.FormValue("volume"))
  writeJson(w, r, store.Status())
}
func storeHandler(w http.ResponseWriter, r *http.Request) {
  switch r.Method {
  case "GET":
    GetHandler(w, r)
  case "DELETE":
    DeleteHandler(w, r)
  case "POST":
    PostHandler(w, r)
  }
}
func GetHandler(w http.ResponseWriter, r *http.Request) {
  n := new(storage.Needle)
  vid, fid, ext := parseURLPath(r.URL.Path)
  volumeId, _ := strconv.ParseUint(vid, 10, 64)
  n.ParsePath(fid)

  if *IsDebug {
    log.Println("volume", volumeId, "reading", n)
  }
  cookie := n.Cookie
  count, e := store.Read(volumeId, n)
  if *IsDebug {
    log.Println("read bytes", count, "error", e)
  }
  if n.Cookie != cookie {
    log.Println("request with unmaching cookie from ", r.RemoteAddr, "agent", r.UserAgent())
    return
  }
  if ext != "" {
    mtype := mime.TypeByExtension(ext)
    w.Header().Set("Content-Type", mtype)
    if storage.IsCompressable(ext, mtype){
      if strings.Contains(r.Header.Get("Accept-Encoding"), "gzip"){
        w.Header().Set("Content-Encoding", "gzip")
      }else{
        n.Data = storage.UnGzipData(n.Data)
      }
    }
  }
  w.Write(n.Data)
}
func PostHandler(w http.ResponseWriter, r *http.Request) {
  vid, _, _ := parseURLPath(r.URL.Path)
  volumeId, e := strconv.ParseUint(vid, 10, 64)
  if e != nil {
    writeJson(w, r, e)
  } else {
    needle, ne := storage.NewNeedle(r)
    if ne != nil {
      writeJson(w, r, ne)
    } else {
      ret := store.Write(volumeId, needle)
      m := make(map[string]uint32)
      m["size"] = ret
      writeJson(w, r, m)
    }
  }
}
func DeleteHandler(w http.ResponseWriter, r *http.Request) {
  n := new(storage.Needle)
  vid, fid, _ := parseURLPath(r.URL.Path)
  volumeId, _ := strconv.ParseUint(vid, 10, 64)
  n.ParsePath(fid)

  if *IsDebug {
    log.Println("deleting", n)
  }

  cookie := n.Cookie
  count, ok := store.Read(volumeId, n)

  if ok != nil {
    m := make(map[string]uint32)
    m["size"] = 0
    writeJson(w, r, m)
    return
  }

  if n.Cookie != cookie {
    log.Println("delete with unmaching cookie from ", r.RemoteAddr, "agent", r.UserAgent())
    return
  }

  n.Size = 0
  store.Delete(volumeId, n)
  m := make(map[string]uint32)
  m["size"] = uint32(count)
  writeJson(w, r, m)
}
func parseURLPath(path string) (vid, fid, ext string) {
  sepIndex := strings.LastIndex(path, "/")
  commaIndex := strings.LastIndex(path[sepIndex:], ",")
  if commaIndex <= 0 {
    if "favicon.ico" != path[sepIndex+1:] {
      log.Println("unknown file id", path[sepIndex+1:])
    }
    return
  }
  dotIndex := strings.LastIndex(path[sepIndex:], ".")
  vid = path[sepIndex+1 : commaIndex]
  fid = path[commaIndex+1:]
  ext = ""
  if dotIndex > 0 {
    fid = path[commaIndex+1 : dotIndex]
    ext = path[dotIndex:]
  }
  return
}

func runVolume(cmd *Command, args []string) bool {
  //TODO: now default to 1G, this value should come from server?
  store = storage.NewStore(*port, *publicUrl, *chunkFolder, *volumes)
  defer store.Close()
  http.HandleFunc("/", storeHandler)
  http.HandleFunc("/status", statusHandler)
  http.HandleFunc("/add_volume", addVolumeHandler)

  go func() {
    for {
      store.Join(*metaServer)
      time.Sleep(time.Duration(float32(*pulse*1e3)*(1+rand.Float32())) * time.Millisecond)
    }
  }()
  log.Println("store joined at", *metaServer)

  log.Println("Start storage service at http://127.0.0.1:"+strconv.Itoa(*port), "public url", *publicUrl)
  e := http.ListenAndServe(":"+strconv.Itoa(*port), nil)
  if e != nil {
    log.Fatalf("Fail to start:", e)
  }
  return true
}