func distributedOperation(masterNode string, store *storage.Store, volumeId storage.VolumeId, op func(location operation.Location) error) error {
if lookupResult, lookupErr := operation.Lookup(masterNode, volumeId.String()); lookupErr == nil {
length := 0
selfUrl := (store.Ip + ":" + strconv.Itoa(store.Port))
results := make(chan RemoteResult)
for _, location := range lookupResult.Locations {
if location.Url != selfUrl {
length++
go func(location operation.Location, results chan RemoteResult) {
results <- RemoteResult{location.Url, op(location)}
}(location, results)
}
}
ret := DistributedOperationResult(make(map[string]error))
for i := 0; i < length; i++ {
result := <-results
ret[result.Host] = result.Error
}
if volume := store.GetVolume(volumeId); volume != nil {
if length+1 < volume.ReplicaPlacement.GetCopyCount() {
return fmt.Errorf("replicating opetations [%d] is less than volume's replication copy count [%d]", length+1, volume.ReplicaPlacement.GetCopyCount())
}
}
return ret.Error()
} else {
glog.V(0).Infoln()
return fmt.Errorf("Failed to lookup for %d: %v", volumeId, lookupErr)
}
return nil
}
func ReplicatedWrite(masterNode string, s *storage.Store,
volumeId storage.VolumeId, needle *storage.Needle,
r *http.Request) (size uint32, errorStatus string) {
//check JWT
jwt := security.GetJwt(r)
defer func() {
if errorStatus == "" {
return
}
ReplicatedDelete(masterNode, s, volumeId, needle, r)
}()
ret, err := s.Write(volumeId, needle)
if err != nil {
errorStatus = "Failed to write to local disk (" + err.Error() + ")"
} else if ret <= 0 {
errorStatus = "Failed to write to local disk"
}
//send to other replica locations
if r.FormValue("type") != "replicate" {
repWrite := func(location operation.Location) bool {
args := url.Values{
"type": {"replicate"},
}
if needle.LastModified > 0 {
args.Set("ts", strconv.FormatUint(needle.LastModified, 10))
}
if needle.IsChunkedManifest() {
args.Set("cm", "true")
}
u := util.MkUrl(location.Url, r.URL.Path, args)
glog.V(4).Infoln("write replication to", u)
_, err := operation.Upload(u,
string(needle.Name), bytes.NewReader(needle.Data), needle.IsGzipped(), string(needle.Mime),
jwt)
if err != nil {
glog.V(0).Infof("write replication to %s err, %v", u, err)
}
return err == nil
}
if !distributedOperation(masterNode, s, volumeId, repWrite) {
ret = 0
errorStatus = "Failed to write to replicas for volume " + volumeId.String()
}
}
size = ret
return
}
func ReplicatedWrite(masterNode string, s *storage.Store,
volumeId storage.VolumeId, needle *storage.Needle,
r *http.Request) (size uint32, errorStatus string) {
//check JWT
jwt := security.GetJwt(r)
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 err = distributedOperation(masterNode, s, volumeId, func(location operation.Location) error {
u := url.URL{
Scheme: "http",
Host: location.Url,
Path: r.URL.Path,
}
q := url.Values{
"type": {"replicate"},
}
if needle.LastModified > 0 {
q.Set("ts", strconv.FormatUint(needle.LastModified, 10))
}
if needle.IsChunkedManifest() {
q.Set("cm", "true")
}
u.RawQuery = q.Encode()
_, err := operation.Upload(u.String(),
string(needle.Name), bytes.NewReader(needle.Data), needle.IsGzipped(), string(needle.Mime),
jwt)
return err
}); err != nil {
ret = 0
errorStatus = fmt.Sprintf("Failed to write to replicas for volume %d: %v", volumeId, err)
}
}
}
size = ret
return
}
func distributedOperation(masterNode string, store *storage.Store, volumeId storage.VolumeId, op func(location operation.Location) bool) bool {
collection := ""
if v := store.GetVolume(volumeId); v != nil {
collection = v.Collection
}
if lookupResult, lookupErr := operation.LookupNoCache(masterNode, volumeId.String(), collection); lookupErr == nil {
length := 0
selfUrl := net.JoinHostPort(store.GetIP(), 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
}
if rp := store.GetVolumeReplicaPlacement(volumeId); rp != nil {
if length+1 < rp.GetCopyCount() {
glog.V(0).Infof("replicating opetations [%d] is less than volume's replication copy count [%d]", length+1, rp.GetCopyCount())
ret = false
}
}
return ret
} else {
glog.V(0).Infoln("Failed to lookup for", volumeId, lookupErr.Error())
}
return false
}
func ReplicatedDelete(masterNode string, store *storage.Store,
volumeId storage.VolumeId, n *storage.Needle,
r *http.Request) (uint32, error) {
//check JWT
jwt := security.GetJwt(r)
ret, err := store.Delete(volumeId, n)
if err != nil {
glog.V(0).Infoln("delete error:", err)
return ret, err
}
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 err = distributedOperation(masterNode, store, volumeId, func(location operation.Location) error {
return util.Delete("http://"+location.Url+r.URL.Path+"?type=replicate", jwt)
}); err != nil {
ret = 0
}
}
}
return ret, err
}
func ReplicatedDelete(masterNode string, store *storage.Store,
volumeId storage.VolumeId, n *storage.Needle,
r *http.Request) (ret uint32) {
//check JWT
jwt := security.GetJwt(r)
ret, err := store.Delete(volumeId, n)
if err != nil {
glog.V(0).Infoln("delete error:", err)
return
}
//send to other replica locations
if r.FormValue("type") != "replicate" {
if !distributedOperation(masterNode, store, volumeId, func(location operation.Location) bool {
return nil == util.Delete("http://"+location.Url+r.URL.Path+"?type=replicate", jwt)
}) {
ret = 0
}
}
return
}