func (reader *sizeReader) Read(p []byte) (int, error) {
if reader.CurrentSize >= reader.MaxSize {
fog.Debug("returning 0 bytes and EOF")
return 0, io.EOF
}
bytesLeft := reader.MaxSize - reader.CurrentSize
var bytesToSend uint64
var err error
if bytesLeft > uint64(len(p)) {
bytesToSend = uint64(len(p))
} else {
bytesToSend = bytesLeft
err = io.EOF
fog.Debug("returning %d bytes and EOF", bytesToSend)
}
for i := 0; i < int(bytesToSend); i++ {
p[i] = 'a'
}
reader.CurrentSize += bytesToSend
currentMB := reader.CurrentSize / (1024 * 1024)
if currentMB > reader.ReportedMB {
fog.Debug("size reader %dmb", currentMB)
reader.ReportedMB = currentMB
}
return int(bytesToSend), err
}
func testPOST(serviceDomain string, useTLS bool) {
var contentLength uint64 = 1024 * 1024 * 1024
fog.Debug("start post %dmb", contentLength/(1024*1024))
client, scheme := getClient(useTLS)
url := fmt.Sprintf("%s://%s/admin", scheme, serviceDomain)
bodyReader := tools.NewSizeReader(contentLength)
request, err := http.NewRequest("POST", url, bodyReader)
if err != nil {
fog.Critical("NewRequest (POST) failed %s", err)
}
request.TransferEncoding = []string{"identity"}
request.Header.Add("Content-Type", "text/plain")
request.Header.Add("Content-Length", fmt.Sprintf("%s", contentLength))
request.ContentLength = int64(contentLength)
response, err := client.Do(request)
if err != nil {
fog.Error("post %s", err)
return
}
tools.ReadAndDiscard(response.Body)
response.Body.Close()
fog.Debug("finished post %s", response.Status)
}
func (s serverImpl) handleGET(w http.ResponseWriter, req *http.Request) {
fog.Debug("(%s) got request %s %s", s.Name, req.Method, req.URL)
if req.Body != nil {
tools.ReadAndDiscard(req.Body)
req.Body.Close()
}
var contentLength uint64 = 1024 * 1024 * 1024
fog.Debug("response body %dmb", contentLength/(1024*1024))
bodyReader := tools.NewSizeReader(contentLength)
http.ServeContent(w, req, "content.txt", time.Now(), bodyReader)
}
// FindMaxAvailSpaceID returns the space id with the most space available
func (info FileSpaceMap) FindMaxAvailSpaceID(purpose string) (uint32, error) {
var maxAvailSpace uint64
var maxAvailSpaceID uint32
var found bool
var statfsBuffer syscall.Statfs_t
for _, entry := range info[purpose] {
if err := syscall.Statfs(entry.Path, &statfsBuffer); err != nil {
return 0, fmt.Errorf("syscall.Statfs(%s, ...) %s", entry.Path, err)
}
availSpace := uint64(statfsBuffer.Bsize) * statfsBuffer.Bavail
fog.Debug("(%d) %s available=%d", entry.SpaceID, entry.Path, availSpace)
if availSpace > maxAvailSpace {
found = true
maxAvailSpace = availSpace
maxAvailSpaceID = entry.SpaceID
}
}
if !found {
return 0, fmt.Errorf("no space found")
}
return maxAvailSpaceID, nil
}
// NewEventSubSocketHandler returns a function that handles event notifications
func NewEventSubSocketHandler(eventSubSocket *zmq4.Socket) func(zmq4.State) error {
var nodeIDMap map[string]uint32
var err error
if nodeIDMap, err = centraldb.GetNodeIDMap(); err != nil {
fog.Critical("centraldb.GetNodeIDMap() failed %s", err)
}
return func(_ zmq4.State) error {
var err error
var ok bool
var webWriterStart msg.WebWriterStart
var timestamp time.Time
var sourceNodeID uint32
marshalledMessage, err := eventSubSocket.RecvMessage(0)
if err != nil {
return fmt.Errorf("RecvMessage %s", err)
}
// the 0th part should be the topic, we skip that
err = json.Unmarshal([]byte(marshalledMessage[1]), &webWriterStart)
if err != nil {
return fmt.Errorf("Unmarshal %s", err)
}
if webWriterStart.MessageType != "web-writer-start" {
return fmt.Errorf("unknown message type '%s'",
webWriterStart.MessageType)
}
timestamp, err = tools.ParseTimestampRepr(webWriterStart.TimestampRepr)
if err != nil {
return fmt.Errorf("unable to parse %s %s",
webWriterStart.TimestampRepr, err)
}
sourceNodeID, ok = nodeIDMap[webWriterStart.SourceNodeName]
if !ok {
return fmt.Errorf("unknown source_node_name %s",
webWriterStart.SourceNodeName)
}
fog.Debug("cancel-segments-from-node %s", webWriterStart.SourceNodeName)
// cancel all all segment rows
// * from a specifiic source node
// * are in active status
// * with a timestamp earlier than the specified time.
// This is triggered by a web server restart
stmt := nodedb.Stmts["cancel-segments-from-node"]
if _, err = stmt.Exec(sourceNodeID, timestamp); err != nil {
return fmt.Errorf("cancel-segments-from-node %s", err)
}
return nil
}
}
func (s serverImpl) handlePOST(w http.ResponseWriter, req *http.Request) {
fog.Debug("(%s) got request %s %s", s.Name, req.Method, req.URL)
if req.Body != nil {
tools.ReadAndDiscard(req.Body)
req.Body.Close()
}
io.WriteString(w, "hello, world!\n")
}
// main entry point for data writer
func main() {
var err error
var writerSocket *zmq4.Socket
var eventSubSocket *zmq4.Socket
fog.Info("program starts")
if writerSocket, err = createWriterSocket(); err != nil {
fog.Critical("createWriterSocket %s", err)
}
defer writerSocket.Close()
fog.Info("binding writer socket to %s", dataWriterAddress)
if err = writerSocket.Bind(dataWriterAddress); err != nil {
fog.Critical("Bind(%s) %s", dataWriterAddress, err)
}
if eventSubSocket, err = createEventSubSocket(); err != nil {
fog.Critical("createEventSubSocket %s", err)
}
defer eventSubSocket.Close()
fog.Info("connecting event sub socket to %s", eventAggregatorPubAddress)
if err = eventSubSocket.Connect(eventAggregatorPubAddress); err != nil {
fog.Critical("Connect(%s) %s", eventAggregatorPubAddress, err)
}
messageChan := NewMessageHandler()
reactor := zmq4.NewReactor()
reactor.AddChannel(tools.NewSignalWatcher(), 1, tools.SigtermHandler)
reactor.AddSocket(writerSocket, zmq4.POLLIN,
NewWriterSocketHandler(writerSocket, messageChan))
reactor.AddSocket(eventSubSocket, zmq4.POLLIN,
NewEventSubSocketHandler(eventSubSocket))
fog.Debug("starting reactor.Run")
reactor.SetVerbose(true)
err = reactor.Run(reactorPollingInterval)
if err == tools.SigtermError {
fog.Info("program terminates normally due to SIGTERM")
} else if errno, ok := err.(syscall.Errno); ok {
// we can get 'interrupted system call' if we get SIGTERM while
// a socket is waiting on a read. That's not too bad.
if errno == syscall.EINTR {
fog.Warn("reactor.Run returns '%s' assuming SIGTERM", errno)
} else {
fog.Error("reactor.Run returns %T '%s'", errno, errno)
}
} else {
fog.Error("reactor.Run returns %T %s", err, err)
}
}
func testGET(serviceDomain string, useTLS bool) {
fog.Debug("start get")
client, scheme := getClient(useTLS)
url := fmt.Sprintf("%s://%s/admin", scheme, serviceDomain)
request, err := http.NewRequest("GET", url, nil)
if err != nil {
fog.Critical("NewRequest (GET) failed %s", err)
}
response, err := client.Do(request)
if err != nil {
fog.Error("get %s", err)
return
}
fog.Debug("reading GET response body")
tools.ReadAndDiscard(response.Body)
response.Body.Close()
fog.Debug("finished get %s", response.Status)
}
// FinishConjoinedArchive completes a conjoined archive
func handleFinishConjoinedArchive(state *writerState, request requestFinishConjoinedArchive) {
conjoined := request.Conjoined
var err error
var ok bool
var handoffNodeID uint32
var timestamp time.Time
fog.Debug("%s FinishConjoinedArchive %s", conjoined.UserRequestID, conjoined)
if timestamp, err = tools.ParseTimestampRepr(conjoined.TimestampRepr); err != nil {
request.resultChan <- fmt.Errorf("unable to parse timestamp %s", err)
return
}
if conjoined.HandoffNodeName != "" {
if handoffNodeID, ok = state.NodeIDMap[conjoined.HandoffNodeName]; !ok {
request.resultChan <- fmt.Errorf("unknown handoff node %s", conjoined.HandoffNodeName)
}
stmt := nodedb.Stmts["finish-conjoined-for-handoff"]
_, err = stmt.Exec(
timestamp,
conjoined.CollectionID,
conjoined.Key,
conjoined.UnifiedID,
handoffNodeID)
if err != nil {
request.resultChan <- fmt.Errorf("finish-conjoined-for-handoff %s", err)
return
}
} else {
stmt := nodedb.Stmts["finish-conjoined"]
_, err = stmt.Exec(
timestamp,
conjoined.CollectionID,
conjoined.Key,
conjoined.UnifiedID)
if err != nil {
request.resultChan <- fmt.Errorf("finish-conjoined %s", err)
return
}
}
request.resultChan <- nil
}
// SanityCheck verifies that the file info map is valid
func (info FileSpaceMap) SanityCheck(repositoryPath string) error {
for _, purpose := range FileSpacePurpose {
for _, entry := range info[purpose] {
fog.Debug("%s (%d) %s", purpose, entry.SpaceID, entry.Path)
symlinkPath := path.Join(repositoryPath,
fmt.Sprintf("%d", entry.SpaceID))
destPath, err := os.Readlink(symlinkPath)
if err != nil {
return fmt.Errorf("(%d) os.Readlink(%s) %s", entry.SpaceID,
symlinkPath, err)
}
if destPath != entry.Path {
return fmt.Errorf("(%d) path mismatch %s != %s", entry.SpaceID,
destPath, entry.Path)
}
}
}
return nil
}
// NewOutputValueFile creates an entity implmenting the OutputValueFile interface
func NewOutputValueFile(fileSpaceInfo tools.FileSpaceInfo) (OutputValueFile, error) {
var valueFile outputValueFile
var err error
valueFile.creationTime = tools.Timestamp()
valueFile.md5Sum = md5.New()
valueFile.collectionIDSet = make(map[uint32]struct{})
repositoryPath := os.Getenv("NIMBUSIO_REPOSITORY_PATH")
if valueFile.spaceID, err = fileSpaceInfo.FindMaxAvailSpaceID(tools.FileSpaceJournal); err != nil {
return nil, err
}
if err = valueFile.insertValueFileRow(); err != nil {
return nil, err
}
valueFile.filePath = tools.ComputeValueFilePath(repositoryPath, valueFile.spaceID,
valueFile.valueFileID)
fog.Debug("NewOutputValueFile %s", valueFile.filePath)
dirPath := path.Dir(valueFile.filePath)
if err = os.MkdirAll(dirPath, os.ModeDir|0755); err != nil {
return nil, fmt.Errorf("os.MkdirAll(%s...", err)
}
valueFile.fileHandle, err = os.Create(valueFile.filePath)
if err != nil {
return nil, fmt.Errorf("os.Create(%s) %s", valueFile.filePath, err)
}
err = syscall.Fallocate(int(valueFile.fileHandle.Fd()), 0, 0,
int64(MaxValueFileSize))
if err != nil {
return nil, fmt.Errorf("Fallocate failed %s", err)
}
valueFile.enableFsync = os.Getenv("NIMBUSIO_ENABLE_FSYNC") == "1"
fog.Info("NewOutputValueFile: NIMBUSIO_ENABLE_FSYNC = %t", valueFile.enableFsync)
return &valueFile, nil
}
// Close the underling file and update the database row
func (valueFile *outputValueFile) Close() error {
if err := valueFile.Sync(); err != nil {
return fmt.Errorf("Sync() %s %s", valueFile.filePath, err)
}
if err := valueFile.fileHandle.Close(); err != nil {
return fmt.Errorf("Close() %s %s", valueFile.filePath, err)
}
if valueFile.bytesWritten == 0 {
fog.Debug("OutputValueFile removing empty file %s", valueFile.filePath)
return os.Remove(valueFile.filePath)
}
if err := valueFile.updateValueFileRow(); err != nil {
return err
}
return nil
}
// CancelSegment stops storing the segment
func handleCancelSegment(state *writerState, request requestCancelSegment) {
cancel := request.Cancel
var err error
fog.Debug("%s CancelSegment", cancel.UserRequestID)
key := segmentKey{cancel.UnifiedID, cancel.ConjoinedPart,
cancel.SegmentNum}
delete(state.SegmentMap, key)
stmt := nodedb.Stmts["cancel-segment"]
_, err = stmt.Exec(
cancel.UnifiedID,
cancel.ConjoinedPart,
cancel.SegmentNum)
if err != nil {
request.resultChan <- fmt.Errorf("cancel-segment %s", err)
return
}
request.resultChan <- nil
}
// DestroyKey makes a key inaccessible
func handleDestroyKey(state *writerState, request requestDestroyKey) {
destroyKey := request.DestroyKey
var err error
var ok bool
var timestamp time.Time
var sourceNodeID uint32
var handoffNodeID uint32
fog.Debug("DestroyKey (%d)", destroyKey.UnifiedIDToDestroy)
if sourceNodeID, ok = state.NodeIDMap[destroyKey.SourceNodeName]; !ok {
request.resultChan <- fmt.Errorf("unknown source node %s", destroyKey.SourceNodeName)
return
}
if timestamp, err = tools.ParseTimestampRepr(destroyKey.TimestampRepr); err != nil {
request.resultChan <- fmt.Errorf("unable to parse timestamp %s", err)
return
}
if destroyKey.UnifiedIDToDestroy > 0 {
if destroyKey.HandoffNodeName != "" {
if handoffNodeID, ok = state.NodeIDMap[destroyKey.HandoffNodeName]; !ok {
request.resultChan <- fmt.Errorf("unknown handoff node %s", destroyKey.HandoffNodeName)
return
}
stmt := nodedb.Stmts["new-tombstone-for-unified-id-for-handoff"]
_, err = stmt.Exec(
destroyKey.CollectionID,
destroyKey.Key,
destroyKey.UnifiedID,
timestamp,
destroyKey.SegmentNum,
destroyKey.UnifiedIDToDestroy,
sourceNodeID,
handoffNodeID)
if err != nil {
request.resultChan <- fmt.Errorf("new-tombstone-for-unified-id-for-handoff %d %s",
destroyKey.UnifiedIDToDestroy, err)
return
}
} else {
stmt := nodedb.Stmts["new-tombstone-for-unified-id"]
_, err = stmt.Exec(
destroyKey.CollectionID,
destroyKey.Key,
destroyKey.UnifiedID,
timestamp,
destroyKey.SegmentNum,
destroyKey.UnifiedIDToDestroy,
sourceNodeID)
if err != nil {
request.resultChan <- fmt.Errorf("new-tombstone-for-unified-id %d %s",
destroyKey.UnifiedIDToDestroy, err)
return
}
}
stmt := nodedb.Stmts["delete-conjoined-for-unified-id"]
_, err = stmt.Exec(
timestamp,
destroyKey.CollectionID,
destroyKey.Key,
destroyKey.UnifiedIDToDestroy)
if err != nil {
request.resultChan <- fmt.Errorf("delete-conjoined-for-unified-id %d %s",
destroyKey.UnifiedIDToDestroy, err)
return
}
} else {
if destroyKey.HandoffNodeName != "" {
if handoffNodeID, ok = state.NodeIDMap[destroyKey.HandoffNodeName]; !ok {
request.resultChan <- fmt.Errorf("unknown handoff node %s", destroyKey.HandoffNodeName)
return
}
stmt := nodedb.Stmts["new-tombstone-for-handoff"]
_, err = stmt.Exec(
destroyKey.CollectionID,
destroyKey.Key,
destroyKey.UnifiedID,
timestamp,
destroyKey.SegmentNum,
sourceNodeID,
handoffNodeID)
if err != nil {
request.resultChan <- fmt.Errorf("new-tombstone-for-handoff %s", err)
return
}
} else {
stmt := nodedb.Stmts["new-tombstone"]
_, err = stmt.Exec(
destroyKey.CollectionID,
destroyKey.Key,
destroyKey.UnifiedID,
timestamp,
destroyKey.SegmentNum,
sourceNodeID)
if err != nil {
request.resultChan <- fmt.Errorf("new-tombstone %s", err)
return
}
}
stmt := nodedb.Stmts["delete-conjoined"]
_, err = stmt.Exec(
timestamp,
destroyKey.CollectionID,
destroyKey.Key,
destroyKey.UnifiedID)
if err != nil {
request.resultChan <- fmt.Errorf("delete-conjoined %s", err)
return
}
}
request.resultChan <- nil
}
// FinishSegment finishes storing the segment
func handleFinishSegment(state *writerState, request requestFinishSegment) {
userRequestID := request.UserRequestID
segment := request.Segment
file := request.File
metaData := request.MetaData
var err error
var md5Digest []byte
var timestamp time.Time
fog.Debug("%s FinishSegment", userRequestID)
key := segmentKey{segment.UnifiedID, segment.ConjoinedPart,
segment.SegmentNum}
entry, ok := state.SegmentMap[key]
if !ok {
request.resultChan <- fmt.Errorf("FinishSegment unknown segment %s", key)
return
}
delete(state.SegmentMap, key)
md5Digest, err = base64.StdEncoding.DecodeString(file.EncodedFileMD5Digest)
if err != nil {
request.resultChan <- err
return
}
if timestamp, err = tools.ParseTimestampRepr(segment.TimestampRepr); err != nil {
request.resultChan <- fmt.Errorf("unable to parse timestamp %s", err)
return
}
stmt := nodedb.Stmts["finish-segment"]
_, err = stmt.Exec(
file.FileSize,
file.FileAdler32,
md5Digest,
entry.SegmentID)
if err != nil {
request.resultChan <- fmt.Errorf("finish-segment %s", err)
return
}
for _, metaEntry := range metaData {
stmt := nodedb.Stmts["new-meta-data"]
_, err = stmt.Exec(
segment.CollectionID,
entry.SegmentID,
metaEntry.Key,
metaEntry.Value,
timestamp)
if err != nil {
request.resultChan <- fmt.Errorf("new-meta-data %s", err)
return
}
}
request.resultChan <- nil
}
// handleConnection manages one HTTP connection
// expected to be run in a goroutine
func handleConnection(router routing.Router, conn net.Conn) {
defer conn.Close()
const bufferSize = 64 * 1024
var err error
requestID, err := tools.CreateUUID()
if err != nil {
fog.Error("%s tools.CreateUUID(): %s", conn.RemoteAddr().String(), err)
return
}
fog.Info("%s starts %s", requestID, conn.RemoteAddr().String())
request, err := http.ReadRequest(bufio.NewReaderSize(conn, bufferSize))
if err != nil {
fog.Error("%s %s ReadRequest failed: %s", requestID,
conn.RemoteAddr().String(), err)
fog.Info("%s aborts", requestID)
return
}
// change the URL to point to our internal host
request.URL.Host, err = router.Route(requestID, request)
if err != nil {
routerErr, ok := err.(routing.RouterError)
if ok {
fog.Error("%s %s, %s router error: %s",
requestID, request.Method, request.URL, err)
sendErrorReply(conn, routerErr.HTTPCode(), routerErr.ErrorMessage())
} else {
fog.Error("%s %s, %s Unexpected error type: %T %s",
requestID, request.Method, request.URL, err, err)
}
fog.Info("%s aborts", requestID)
return
}
request.URL.Scheme = "http"
// heave the incoming RequestURI: can't be set in a client request
request.RequestURI = ""
modifyHeaders(request, conn.RemoteAddr().String(), requestID)
fog.Debug("%s routing %s %s", requestID, request.Method, request.URL)
// TODO: cache the connection to the internal server
internalConn, err := net.Dial("tcp", request.URL.Host)
if err != nil {
fog.Error("%s %s, %s unable to dial internal server: %s",
requestID, request.Method, request.URL, err)
sendErrorReply(conn, http.StatusInternalServerError, err.Error())
fog.Info("%s aborts", requestID)
return
}
defer internalConn.Close()
err = request.Write(bufio.NewWriterSize(internalConn, bufferSize))
if err != nil {
fog.Error("%s %s, %s request.Write: %s",
requestID, request.Method, request.URL, err)
sendErrorReply(conn, http.StatusInternalServerError, err.Error())
fog.Info("%s aborts", requestID)
return
}
request.Body.Close()
response, err := http.ReadResponse(bufio.NewReaderSize(internalConn, bufferSize),
request)
if err != nil {
fog.Error("%s %s, %s http.ReadResponse: %s",
requestID, request.Method, request.URL, err)
sendErrorReply(conn, http.StatusInternalServerError, err.Error())
fog.Info("%s aborts", requestID)
return
}
if err := response.Write(bufio.NewWriterSize(conn, bufferSize)); err != nil {
fog.Error("%s %s, %s error sending response: %s",
requestID, request.Method, request.URL, err)
}
response.Body.Close()
fog.Info("%s ends (%d) %s", requestID, response.StatusCode, response.Status)
}
func handleStartSegment(state *writerState, request requestStartSegment) {
userRequestID := request.UserRequestID
segment := request.Segment
nodeNames := request.NodeNames
var entry segmentMapEntry
var err error
var sourceNodeID uint32
var handoffNodeID uint32
var ok bool
var timestamp time.Time
fog.Debug("%s StartSegment", userRequestID)
if sourceNodeID, ok = state.NodeIDMap[nodeNames.SourceNodeName]; !ok {
request.resultChan <- fmt.Errorf("unknown source node %s", nodeNames.SourceNodeName)
return
}
if timestamp, err = tools.ParseTimestampRepr(segment.TimestampRepr); err != nil {
request.resultChan <- fmt.Errorf("unable to parse timestamp %s", err)
return
}
if nodeNames.HandoffNodeName != "" {
if handoffNodeID, ok = state.NodeIDMap[nodeNames.HandoffNodeName]; !ok {
request.resultChan <- fmt.Errorf("unknown handoff node %s", nodeNames.HandoffNodeName)
return
}
stmt := nodedb.Stmts["new-segment-for-handoff"]
row := stmt.QueryRow(
segment.CollectionID,
segment.Key,
segment.UnifiedID,
timestamp,
segment.SegmentNum,
segment.ConjoinedPart,
sourceNodeID,
handoffNodeID)
if err = row.Scan(&entry.SegmentID); err != nil {
request.resultChan <- err
return
}
} else {
stmt := nodedb.Stmts["new-segment"]
row := stmt.QueryRow(
segment.CollectionID,
segment.Key,
segment.UnifiedID,
timestamp,
segment.SegmentNum,
segment.ConjoinedPart,
sourceNodeID)
if err = row.Scan(&entry.SegmentID); err != nil {
request.resultChan <- err
return
}
}
entry.LastActionTime = tools.Timestamp()
key := segmentKey{segment.UnifiedID, segment.ConjoinedPart,
segment.SegmentNum}
state.SegmentMap[key] = entry
request.resultChan <- nil
}
// Route reads a request and decides where it should go <host:port>
func (router *routerImpl) Route(requestID string, req *http.Request) (string, error) {
var err error
hostName := req.Host
router.requestCounter += 1
fog.Debug("%s host=%s, method=%s, URL=%s", requestID, hostName, req.Method,
req.URL)
// TODO: be able to handle http requests from http 1.0 clients w/o a
// host header to at least the website, if nothing else.
if hostName == "" {
return "", routerErrorImpl{httpCode: http.StatusBadRequest,
errorMessage: "HOST header not found"}
}
routingHostName := strings.Split(hostName, ":")[0]
if !strings.HasSuffix(routingHostName, serviceDomain) {
return "", routerErrorImpl{httpCode: http.StatusNotFound,
errorMessage: fmt.Sprintf("Invalid HOST '%s'", routingHostName)}
}
var routingMethod string
var routedHost string
if routingHostName == serviceDomain {
// this is not a request specific to any particular collection
// TODO: figure out how to route these requests.
// in production, this might not matter.
routingMethod = "management API"
routedHost = router.managmentAPIDests.Next()
fog.Debug("%s %s routed to %s by %s", requestID, req.URL.Path,
routedHost, routingMethod)
return routedHost, nil
}
destPort, ok := destPortMap[req.Method]
if !ok {
return "", routerErrorImpl{httpCode: http.StatusBadRequest,
errorMessage: fmt.Sprintf("Unknown method '%s'", req.Method)}
}
collectionName := parseCollectionFromHostName(routingHostName)
if collectionName == "" {
return "", routerErrorImpl{httpCode: http.StatusNotFound,
errorMessage: fmt.Sprintf("Unparseable host name '%s'", hostName)}
}
hostsForCollection, err := router.centralDB.GetHostsForCollection(collectionName)
if err != nil {
fog.Error("database error: collection '%s' %s", collectionName, err)
return "", routerErrorImpl{httpCode: http.StatusInternalServerError,
errorMessage: fmt.Sprintf("database error: collection '%s'",
collectionName)}
}
if len(hostsForCollection) == 0 {
return "", routerErrorImpl{httpCode: http.StatusNotFound,
errorMessage: fmt.Sprintf("no hosts for collection '%s'",
collectionName)}
}
availableHosts, err := router.availability.AvailableHosts(
hostsForCollection, destPort)
if err != nil {
return "", routerErrorImpl{httpCode: http.StatusInternalServerError,
errorMessage: fmt.Sprintf("collection '%s': %s", collectionName, err)}
}
if len(availableHosts) == 0 {
// XXX: the python web_director retries here, after a delay.
// IMO, that's what HTTP Status 503 is for
return "", routerErrorImpl{httpCode: http.StatusServiceUnavailable,
errorMessage: fmt.Sprintf("no hosts available for collection '%s'",
collectionName)}
}
switch {
case alwaysRouteToFirstNode:
routingMethod = "NIMBUSIO_WEB_DIRECTOR_ALWAYS_FIRST_NODE"
routedHost = availableHosts[0]
case (req.Method == "GET" || req.Method == "HEAD") &&
strings.HasPrefix(req.URL.Path, "/data/") &&
len(req.URL.Path) > len("/data/"):
routedHost, err = consistentHashDest(hostsForCollection, availableHosts,
collectionName, req.URL.Path)
if err != nil {
return "", routerErrorImpl{httpCode: http.StatusInternalServerError,
errorMessage: fmt.Sprintf("collection '%s': %s", collectionName, err)}
}
routingMethod = "hash"
default:
if router.roundRobinCounter == 0 {
// start the round robin dispatcher at a random number, so all the
// workers don't start on the same point.
n, err := rand.Int(rand.Reader, big.NewInt(int64(len(hostsForCollection))))
if err != nil {
return "", routerErrorImpl{httpCode: http.StatusInternalServerError,
errorMessage: fmt.Sprintf("collection '%s': %s", collectionName, err)}
}
router.roundRobinCounter = n.Uint64()
} else {
router.roundRobinCounter += 1
}
// XXX: the python version works with hostsForCollection and then tries
// to find one in availableHosts. IMO, assuming the group of
// available hosts is fairly stable, we get the same result working
// strictly with availableHosts
i := int(router.roundRobinCounter % uint64(len(availableHosts)))
routedHost = availableHosts[i]
routingMethod = "round robin"
}
fog.Debug("%s %s %s routed to %s by %s", requestID, collectionName,
req.URL.Path, routedHost, routingMethod)
return fmt.Sprintf("%s:%s", routedHost, destPort), nil
}
// Debug prepends literal 'DEBUG' to log message
func (l logData) Debug(text string, args ...interface{}) {
fog.Debug(l.prefix()+text, args...)
}
func ReadAndDiscard(reader io.Reader) {
fog.Debug("ReadAndDiscard starts")
n, err := io.Copy(ioutil.Discard, reader)
fog.Debug("ReadAndDiscard: %d, %v", n, err)
}
func handleStoreSequence(state *writerState, request requestStoreSequence) {
userRequestID := request.UserRequestID
segment := request.Segment
sequence := request.Sequence
data := request.Data
var err error
var md5Digest []byte
var offset uint64
fog.Debug("%s StoreSequence #%d", userRequestID, sequence.SequenceNum)
if state.ValueFile.Size()+sequence.SegmentSize >= MaxValueFileSize {
fog.Info("value file full")
if state.SyncTimer != nil {
state.SyncTimer.Stop()
}
state.SyncTimer = nil
if err = state.ValueFile.Close(); err != nil {
request.resultChan <- storeSequenceResult{Err: fmt.Errorf("error closing value file %s", err)}
return
}
if state.ValueFile, err = NewOutputValueFile(state.FileSpaceInfo); err != nil {
request.resultChan <- storeSequenceResult{Err: fmt.Errorf("error opening value file %s", err)}
return
}
startSyncTimer(state)
}
md5Digest, err = base64.StdEncoding.DecodeString(sequence.EncodedSegmentMD5Digest)
if err != nil {
request.resultChan <- storeSequenceResult{Err: err}
return
}
key := segmentKey{segment.UnifiedID, segment.ConjoinedPart,
segment.SegmentNum}
entry, ok := state.SegmentMap[key]
if !ok {
request.resultChan <- storeSequenceResult{Err: fmt.Errorf("StoreSequence unknown segment %s", key)}
return
}
offset, err = state.ValueFile.Store(segment.CollectionID, entry.SegmentID,
data)
if err != nil {
request.resultChan <- storeSequenceResult{Err: fmt.Errorf("ValueFile.Store %s", err)}
return
}
stmt := nodedb.Stmts["new-segment-sequence"]
_, err = stmt.Exec(
segment.CollectionID,
entry.SegmentID,
sequence.ZfecPaddingSize,
state.ValueFile.ID(),
sequence.SequenceNum,
offset,
sequence.SegmentSize,
md5Digest,
sequence.SegmentAdler32)
if err != nil {
request.resultChan <- storeSequenceResult{Err: fmt.Errorf("new-segment-sequence %s", err)}
}
state.StatGrabber.Accumulate("nimbusio_write_requests", 1)
state.StatGrabber.Accumulate("nimbusio_write_bytes", len(data))
entry.LastActionTime = tools.Timestamp()
state.SegmentMap[key] = entry
request.resultChan <- storeSequenceResult{ValueFileID: state.ValueFile.ID()}
}
// NewWriterSocketHandler returns a function suitable for use as a handler
// by zmq.Reactor
func NewWriterSocketHandler(writerSocket *zmq4.Socket,
messageChan chan<- types.Message) func(zmq4.State) error {
// these messages get only and ack, not a reply
var ackOnlyMessages = map[string]ackOnlyMessageHandler{
"ping": handlePing,
"resilient-server-handshake": handleHandshake,
"resilient-server-signoff": handleSignoff}
return func(_ zmq4.State) error {
var err error
var ok bool
var rawMessage []string
var message types.Message
if rawMessage, err = writerSocket.RecvMessage(0); err != nil {
return fmt.Errorf("RecvMessage %s", err)
}
message.Marshalled = rawMessage[0]
message.Data = []byte(strings.Join(rawMessage[1:], ""))
if message.Type, err = msg.GetMessageType(message.Marshalled); err != nil {
return fmt.Errorf("GetMessageType %s", err)
}
if message.ID, err = msg.GetMessageID(message.Marshalled); err != nil {
return fmt.Errorf("GetMessageID %s", err)
}
reply := map[string]interface{}{
"message-type": "resilient-server-ack",
"message-id": message.ID,
"incoming-type": message.Type,
"accepted": true}
marshalledReply, err := json.Marshal(reply)
if err != nil {
return fmt.Errorf("Marshal %s", err)
}
_, err = writerSocket.SendMessage([]string{string(marshalledReply)})
if err != nil {
return fmt.Errorf("SendMessage %s", err)
}
/* ---------------------------------------------------------------
** 2014-05-21 dougfort:
** The python version of ResiliantServer maintains a dict of
** "client-address" for sending replies, but IMO we don't need
** that here because every message contains "client-address"
** so we can decouple the reply.
** -------------------------------------------------------------*/
handler, ok := ackOnlyMessages[message.Type]
if ok {
handler(message)
return nil
}
fog.Debug("writer-socket-handler received %s %s",
message.Type, message.ID)
messageChan <- message
return nil
}
}
