package replication import ( "bytes" "code.google.com/p/weed-fs/go/glog" "code.google.com/p/weed-fs/go/operation" "code.google.com/p/weed-fs/go/storage" "net/http" "strconv" ) func ReplicatedWrite(masterNode string, s *storage.Store, volumeId storage.VolumeId, needle *storage.Needle, r *http.Request) (size uint32, errorStatus string) { ret, err := s.Write(volumeId, needle) needToReplicate := !s.HasVolume(volumeId) if err != nil { errorStatus = "Failed to write to local disk (" + err.Error() + ")" } else if ret > 0 { needToReplicate = needToReplicate || s.GetVolume(volumeId).NeedToReplicate() } else { errorStatus = "Failed to write to local disk" } if !needToReplicate && ret > 0 { needToReplicate = s.GetVolume(volumeId).NeedToReplicate() } if needToReplicate { //send to other replica locations if r.FormValue("type") != "replicate" { if !distributedOperation(masterNode, s, volumeId, func(location operation.Location) bool { _, err := operation.Upload("http://"+location.Url+r.URL.Path+"?type=replicate&ts="+strconv.FormatUint(needle.LastModified, 10), string(needle.Name), bytes.NewReader(needle.Data), needle.IsGzipped(), string(needle.Mime)) return err == nil }) { ret = 0 errorStatus = "Failed to write to replicas for volume " + volumeId.String() } } } if errorStatus != "" { if _, err = s.Delete(volumeId, needle); err != nil { errorStatus += "\nCannot delete " + strconv.FormatUint(needle.Id, 10) + " from " + volumeId.String() + ": " + err.Error() } else { distributedOperation(masterNode, s, volumeId, func(location operation.Location) bool { return nil == operation.Delete("http://"+location.Url+r.URL.Path+"?type=replicate") }) } } size = ret return } func ReplicatedDelete(masterNode string, store *storage.Store, volumeId storage.VolumeId, n *storage.Needle, r *http.Request) (ret uint32) { ret, err := store.Delete(volumeId, n) if err != nil { glog.V(0).Infoln("delete error:", err) return } needToReplicate := !store.HasVolume(volumeId) if !needToReplicate && ret > 0 { needToReplicate = store.GetVolume(volumeId).NeedToReplicate() } if needToReplicate { //send to other replica locations if r.FormValue("type") != "replicate" { if !distributedOperation(masterNode, store, volumeId, func(location operation.Location) bool { return nil == operation.Delete("http://"+location.Url+r.URL.Path+"?type=replicate") }) { ret = 0 } } } return } func distributedOperation(masterNode string, store *storage.Store, volumeId storage.VolumeId, op func(location operation.Location) bool) bool { if lookupResult, lookupErr := operation.Lookup(masterNode, volumeId); lookupErr == nil { length := 0 selfUrl := (store.Ip + ":" + strconv.Itoa(store.Port)) results := make(chan bool) for _, location := range lookupResult.Locations { if location.Url != selfUrl { length++ go func(location operation.Location, results chan bool) { results <- op(location) }(location, results) } } ret := true for i := 0; i < length; i++ { ret = ret && <-results } return ret } else { glog.V(0).Infoln("Failed to lookup for", volumeId, lookupErr.Error()) } return false }