func (pc *PathCache) Start() (notifyChan chan PathCacheNotification, err error) {
pc.notifyChan = make(chan PathCacheNotification, 10)
pc.stoppedChan = make(chan bool, 1)
pc.startup = sync.WaitGroup{}
go pc.mux()
err = pc.watch()
if err != nil {
// We expect this to occasionally happen due to timing
if err != zk.ErrNoNode {
log.Println(log.ERROR, err)
}
pc.Stop()
return
}
err = pc.watchChildren()
if err != nil {
// We expect this to occasionally happen due to timing
if err != zk.ErrNoNode {
log.Println(log.ERROR, err)
}
pc.Stop()
}
pc.startup.Wait()
return pc.notifyChan, err
}
func (s *SkynetDaemon) StopAllSubServices(requestInfo *skynet.RequestInfo, in daemon.StopAllSubServicesRequest, out *daemon.StopAllSubServicesResponse) (err error) {
var uuids []string
s.serviceLock.Lock()
for uuid := range s.Services {
uuids = append(uuids, uuid)
}
s.serviceLock.Unlock()
out.Stops = make([]daemon.StopSubServiceResponse, len(uuids))
for i, uuid := range uuids {
log.Println(log.TRACE, "Stopping "+uuid)
err = s.StopSubService(requestInfo, daemon.StopSubServiceRequest{UUID: uuid}, &out.Stops[i])
if err != nil {
log.Println(log.ERROR, "Failed to stop subservice "+uuid, err)
return
}
if out.Stops[i].Ok {
out.Count++
}
}
s.saveState()
return
}
// TODO: This should be moved out so that it's run asynchronously
// it should also use a buffered channel so that if a save is already queued it only saves once
func (s *SkynetDaemon) writeStateFile() (err error) {
err = s.stateFile.Truncate(0)
if err != nil {
return
}
_, err = s.stateFile.Seek(0, 0)
if err != nil {
return
}
var b []byte
b, err = json.MarshalIndent(s.Services, "", "\t")
if err != nil {
log.Println(log.ERROR, "Failed to marshall daemon state")
return
}
_, err = s.stateFile.Write(b)
if err != nil {
log.Println(log.ERROR, "Failed to save daemon state")
}
return
}
func (c *ServiceClient) send(retry, giveup time.Duration, ri *skynet.RequestInfo, fn string, in interface{}, out interface{}) (err error) {
if ri == nil {
ri = c.NewRequestInfo()
}
attempts := make(chan sendAttempt)
var retryTicker <-chan time.Time
retryChan := make(chan bool)
if retry > 0 {
retryTicker = time.Tick(retry)
}
var timeoutTimer <-chan time.Time
if giveup > 0 {
timeoutTimer = time.NewTimer(giveup).C
}
attemptCount := 1
go c.attemptSend(retry, attempts, ri, fn, in, out)
for {
select {
case <-retryTicker:
retryChan <- true
case <-retryChan:
attemptCount++
ri.RetryCount++
log.Println(log.TRACE, fmt.Sprintf("Sending Attempt# %d with RequestInfo %+v", attemptCount, ri))
go c.attemptSend(retry, attempts, ri, fn, in, out)
case <-timeoutTimer:
err = RequestTimeout
return
case attempt := <-attempts:
if attempt.err != nil {
log.Println(log.ERROR, "Attempt Error: ", attempt.err)
// If there is no retry timer we need to exit as retries were disabled
if retryTicker == nil {
return err
} else {
// Don't wait for next retry tick retry now
retryChan <- true
}
continue
}
// copy into the caller's value
v := reflect.Indirect(reflect.ValueOf(out))
v.Set(reflect.Indirect(reflect.ValueOf(attempt.result)))
return
}
}
}
// this function is the goroutine that owns this service - all thread-sensitive data needs to
// be manipulated only through here.
func (s *Service) mux() {
loop:
for {
select {
case conn := <-s.connectionChan:
clientID := config.NewUUID()
s.clientMutex.Lock()
s.ClientInfo[clientID] = ClientInfo{
Address: conn.RemoteAddr(),
}
s.clientMutex.Unlock()
// send the server handshake
sh := skynet.ServiceHandshake{
Registered: s.Registered,
ClientID: clientID,
Name: s.Name,
}
encoder := bsonrpc.NewEncoder(conn)
err := encoder.Encode(sh)
if err != nil {
log.Println(log.ERROR, "Failed to encode server handshake", err.Error())
continue
}
if !s.Registered {
log.Println(log.ERROR, "Connection attempted while unregistered. Closing connection")
conn.Close()
continue
}
// read the client handshake
var ch skynet.ClientHandshake
decoder := bsonrpc.NewDecoder(conn)
err = decoder.Decode(&ch)
if err != nil {
log.Println(log.ERROR, "Error calling bsonrpc.NewDecoder: "+err.Error())
continue
}
// here do stuff with the client handshake
go func() {
s.RPCServ.ServeCodec(bsonrpc.NewServerCodec(conn))
}()
case register := <-s.registeredChan:
if register {
s.register()
} else {
s.unregister()
}
case <-s.shutdownChan:
s.shutdown()
case _ = <-s.doneChan:
break loop
}
}
}
func (sc *scodec) ReadRequestHeader(rq *rpc.Request) (err error) {
log.Println(log.TRACE, "RPC Server Entered: ReadRequestHeader")
defer log.Println(log.TRACE, "RPC Server Leaving: ReadRequestHeader")
err = sc.dec.Decode(rq)
if err != nil && err != io.EOF {
log.Println(log.ERROR, "RPC Server Error decoding request header: ", err)
}
return
}
func (sc *scodec) ReadRequestBody(v interface{}) (err error) {
log.Println(log.TRACE, "RPC Server Entered: ReadRequestBody")
defer log.Println(log.TRACE, "RPC Server Leaving: ReadRequestBody")
err = sc.dec.Decode(v)
if err != nil {
log.Println(log.ERROR, "RPC Server Error decoding request body: ", err)
}
return
}
func (sc *scodec) Close() (err error) {
log.Println(log.TRACE, "RPC Server Entered: Close")
defer log.Println(log.TRACE, "RPC Server Leaving: Close")
err = sc.conn.Close()
if err != nil {
log.Println(log.ERROR, "RPC Server Error closing connection: ", err)
return
}
return
}
func (cc *ccodec) ReadResponseHeader(res *rpc.Response) (err error) {
log.Println(log.TRACE, "RPC Server Entered: ReadResponseHeader")
defer log.Println(log.TRACE, "RPC Server Leaving: ReadResponseHeader")
err = cc.dec.Decode(res)
if err != nil {
log.Println(log.ERROR, "RPC Client Error decoding response header: ", err)
}
return
}
func (sd *SkynetDaemon) Started(s *service.Service) {
err := sd.cleanupHost(s.ServiceInfo.UUID)
if err != nil {
log.Println(log.ERROR, "Error cleaning up host", err)
}
err = sd.restoreState()
if err != nil {
log.Println(log.ERROR, "Error restoring state", err)
}
}
func getGiveupTimeout(service, version string) time.Duration {
if d, err := config.String(service, version, "client.timeout.total"); err == nil {
if timeout, err := time.ParseDuration(d); err == nil {
log.Println(log.TRACE, fmt.Sprintf("Using custom giveup duration %q for %q %q", timeout.String(), service, version))
return timeout
}
log.Println(log.ERROR, "Failed to parse client.timeout.total", err)
}
return config.DefaultRetryDuration
}
/*
Conn.SendTimeout() Acts like Send but takes a timeout
*/
func (c *Conn) SendTimeout(ri *skynet.RequestInfo, fn string, in interface{}, out interface{}, timeout time.Duration) (err error) {
if c.IsClosed() {
return ConnectionClosed
}
sin := skynet.ServiceRPCInWrite{
RequestInfo: ri,
Method: fn,
ClientID: c.clientID,
}
var b []byte
b, err = bson.Marshal(in)
if err != nil {
return serviceError{fmt.Sprintf("Error calling bson.Marshal: %v", err)}
}
sin.In = bson.Binary{
0x00,
b,
}
sout := skynet.ServiceRPCOutRead{}
// Set timeout for this request, then set it back to idle timeout
c.setDeadline(timeout)
defer c.setDeadline(c.idleTimeout)
log.Println(log.TRACE, fmt.Sprintf("Sending Method call %s with ClientID %s to: %s", sin.Method, sin.ClientID, c.addr))
err = c.rpcClient.Call(c.serviceName+".Forward", sin, &sout)
if err != nil {
c.Close()
err = serviceError{err.Error()}
return
}
if sout.ErrString != "" {
err = serviceError{sout.ErrString}
return
}
err = bson.Unmarshal(sout.Out, out)
if err != nil {
log.Println(log.ERROR, "Error unmarshalling nested document")
err = serviceError{err.Error()}
}
return
}
func init() {
flagset := flag.NewFlagSet("config", flag.ContinueOnError)
flagset.StringVar(&configFile, "config", "", "Config File")
flagset.StringVar(&uuid, "uuid", "", "uuid")
args, _ := SplitFlagsetFromArgs(flagset, os.Args[1:])
flagset.Parse(args)
// Ensure we have a UUID
if uuid == "" {
uuid = NewUUID()
}
if configFile == "" {
for _, f := range defaultConfigFiles {
if _, err := os.Stat(f); err == nil {
configFile = f
break
}
}
}
if configFile == "" {
log.Println(log.ERROR, "Failed to find config file")
conf = config.NewDefault()
return
}
if _, err := os.Stat(configFile); os.IsNotExist(err) {
log.Println(log.ERROR, "Config file does not exist", err)
conf = config.NewDefault()
return
}
var err error
if conf, err = config.ReadDefault(configFile); err != nil {
conf = config.NewDefault()
log.Fatal(err)
}
// Set default log level from config, this can be overriden at the service level when the service is created
if l, err := conf.RawStringDefault("log.level"); err == nil {
log.SetLogLevel(log.LevelFromString(l))
}
// Set GOMAXPROCS
if i, err := conf.Int("DEFAULT", "runtime.gomaxprocs"); err == nil {
runtime.GOMAXPROCS(i)
}
}
// Wait for existing requests to complete and shutdown service
func (s *Service) shutdown() {
if s.shuttingDown {
return
}
s.shuttingDown = true
s.doneGroup.Add(1)
s.rpcListener.Close()
s.doneChan <- true
s.activeRequests.Wait()
err := skynet.GetServiceManager().Remove(*s.ServiceInfo)
if err != nil {
log.Println(log.ERROR, "Failed to remove service: "+err.Error())
}
skynet.GetServiceManager().Shutdown()
s.Delegate.Stopped(s) // Call user defined callback
s.doneGroup.Done()
}
func (sm *ZookeeperServiceManager) Remove(s skynet.ServiceInfo) (err error) {
log.Println(log.TRACE, "Removing service", s.UUID)
ops := zk.MultiOps{
Delete: []zk.DeleteRequest{
deleteRequest(path.Join("/regions", s.Region, s.UUID), -1),
deleteRequest(path.Join("/services", s.Name, s.Version, s.UUID), -1),
deleteRequest(path.Join("/services", s.Name, s.UUID), -1),
deleteRequest(path.Join("/hosts", s.ServiceAddr.IPAddress, s.UUID), -1),
deleteRequest(path.Join("/instances", s.UUID, "registered"), -1),
deleteRequest(path.Join("/instances", s.UUID, "name"), -1),
deleteRequest(path.Join("/instances", s.UUID, "version"), -1),
deleteRequest(path.Join("/instances", s.UUID, "region"), -1),
deleteRequest(path.Join("/instances", s.UUID, "addr"), -1),
deleteRequest(path.Join("/instances", s.UUID), -1),
},
}
err = sm.conn.Multi(ops)
if err == nil {
delete(sm.managedInstances, s.UUID)
}
// Attempt to remove parent paths for service if they are empty
sm.removePathIfEmpty(path.Join("/hosts", s.ServiceAddr.IPAddress))
sm.removePathIfEmpty(path.Join("/regions", s.Region))
sm.removePathIfEmpty(path.Join("/services", s.Name, s.Version))
sm.removePathIfEmpty(path.Join("/services", s.Name))
return
}
func (sm *ZookeeperServiceManager) Add(s skynet.ServiceInfo) (err error) {
log.Println(log.TRACE, "Adding service to cluster", s.UUID)
err = sm.createPathsForService(s)
if err != nil {
return err
}
ops := zk.MultiOps{
Create: []zk.CreateRequest{
createRequest(path.Join("/regions", s.Region, s.UUID), []byte{}, zk.PermAll, zk.FlagEphemeral),
createRequest(path.Join("/services", s.Name, s.UUID), []byte{}, zk.PermAll, zk.FlagEphemeral),
createRequest(path.Join("/services", s.Name, s.Version, s.UUID), []byte{}, zk.PermAll, zk.FlagEphemeral),
createRequest(path.Join("/hosts", s.ServiceAddr.IPAddress, s.UUID), []byte{}, zk.PermAll, zk.FlagEphemeral),
createRequest(path.Join("/instances", s.UUID), []byte{}, zk.PermAll, 0),
createRequest(path.Join("/instances", s.UUID, "registered"), []byte(strconv.FormatBool(s.Registered)), zk.PermAll, zk.FlagEphemeral),
createRequest(path.Join("/instances", s.UUID, "name"), []byte(s.Name), zk.PermAll, zk.FlagEphemeral),
createRequest(path.Join("/instances", s.UUID, "version"), []byte(s.Version), zk.PermAll, zk.FlagEphemeral),
createRequest(path.Join("/instances", s.UUID, "region"), []byte(s.Region), zk.PermAll, zk.FlagEphemeral),
createRequest(path.Join("/instances", s.UUID, "addr"), []byte(s.ServiceAddr.String()), zk.PermAll, zk.FlagEphemeral),
},
}
err = sm.conn.Multi(ops)
sm.managedInstances[s.UUID] = s
return
}
func (s *Service) listen(addr skynet.BindAddr, bindWait *sync.WaitGroup) {
var err error
s.rpcListener, err = addr.Listen()
if err != nil {
panic(err)
}
log.Printf(log.INFO, "%+v\n", ServiceListening{
Addr: &addr,
ServiceInfo: s.ServiceInfo,
})
// We may have changed port due to conflict, ensure config has the correct port now
a, _ := skynet.BindAddrFromString(addr.String())
s.ServiceAddr.IPAddress = a.IPAddress
s.ServiceAddr.Port = a.Port
bindWait.Done()
for {
conn, err := s.rpcListener.AcceptTCP()
if s.shuttingDown {
break
}
if err != nil && !s.shuttingDown {
log.Println(log.ERROR, "AcceptTCP failed", err)
continue
}
s.connectionChan <- conn
}
}
func (sc *scodec) WriteResponse(rs *rpc.Response, v interface{}) (err error) {
log.Println(log.TRACE, "RPC Server Entered: WriteResponse")
defer log.Println(log.TRACE, "RPC Server Leaving: WriteResponse")
err = sc.enc.Encode(rs)
if err != nil {
log.Println(log.ERROR, "RPC Server Error encoding rpc response: ", err)
return
}
err = sc.enc.Encode(v)
if err != nil {
log.Println(log.ERROR, "RPC Server Error encoding response value: ", err)
return
}
return sc.encBuf.Flush()
}
func (sm *ZookeeperServiceManager) Unregister(uuid string) (err error) {
log.Println(log.TRACE, "Unregister service", uuid)
_, err = sm.conn.Set(path.Join("/instances", uuid, "registered"), []byte("false"), -1)
return
}
func (sm *ZookeeperServiceManager) mux() {
for {
select {
case e := <-sm.session:
switch e.Type {
case zk.EventNodeDeleted, zk.EventNodeChildrenChanged, zk.EventNodeDataChanged:
case zk.EventSession:
// TODO: EventNotWatching
// TODO: StateDisconnected
default:
log.Println(log.TRACE, "Zookeeper Event Received: ", e)
}
case <-sm.done:
// Remove instances that were added by this instance
for _, s := range sm.managedInstances {
sm.Remove(s)
}
sm.cache.Stop()
sm.conn.Close()
return
}
}
}
func (pc *PathCache) watchChildren() error {
if pc.depth == 0 {
return nil
}
children, _, ev, err := pc.serviceManager.conn.ChildrenW(pc.path)
if err != nil {
if err != zk.ErrNoNode {
log.Println(log.ERROR, err)
}
return err
}
go forwardZkEvents(ev, pc.events)
pc.startup.Add(len(children))
for _, c := range children {
if _, ok := pc.children[path.Join(pc.path, c)]; !ok {
go func(c string) {
pc.addChildChan <- c
}(c)
}
}
return nil
}
func (s *Service) serveAdminRequests() {
rId := os.Stderr.Fd() + 2
wId := os.Stderr.Fd() + 3
pipeReader := os.NewFile(uintptr(rId), "")
pipeWriter := os.NewFile(uintptr(wId), "")
s.pipe = daemon.NewPipe(pipeReader, pipeWriter)
b := make([]byte, daemon.MAX_PIPE_BYTES)
for {
n, err := s.pipe.Read(b)
if err != nil {
if err != io.EOF {
log.Printf(log.ERROR, "Error reading from admin pipe "+err.Error())
} else {
// We received EOF, ensure we shutdown (if daemon died we could be orphaned)
s.Shutdown()
}
return
}
cmd := string(b[:n])
log.Println(log.TRACE, "Received "+cmd+" from daemon")
switch cmd {
case "SHUTDOWN":
s.Shutdown()
s.pipe.Write([]byte("ACK"))
break
case "REGISTER":
s.Register()
s.pipe.Write([]byte("ACK"))
case "UNREGISTER":
s.Unregister()
s.pipe.Write([]byte("ACK"))
case "LOG DEBUG", "LOG TRACE", "LOG INFO", "LOG WARN", "LOG ERROR", "LOG FATAL", "LOG PANIC":
parts := strings.Split(cmd, " ")
log.SetLogLevel(log.LevelFromString(parts[1]))
log.Println(log.INFO, "Setting log level to "+parts[1])
s.pipe.Write([]byte("ACK"))
}
}
}
func (cc *ccodec) WriteRequest(req *rpc.Request, v interface{}) (err error) {
log.Println(log.TRACE, "RPC Server Entered: WriteRequest")
defer log.Println(log.TRACE, "RPC Server Leaving: WriteRequest")
err = cc.enc.Encode(req)
if err != nil {
log.Println(log.ERROR, "RPC Client Error enconding request rpc request: ", err)
return
}
err = cc.enc.Encode(v)
if err != nil {
log.Println(log.ERROR, "RPC Client Error enconding request value: ", err)
return
}
return cc.encBuf.Flush()
}
func (cc *ccodec) ReadResponseBody(v interface{}) (err error) {
log.Println(log.TRACE, "RPC Server Entered: ReadResponseBody")
defer log.Println(log.TRACE, "RPC Server Leaving: ReadResponseBody")
if v == nil {
err = errors.New("Response object cannot be nil")
if err != nil {
log.Println(log.ERROR, "RPC Client Error reading response body: ", err)
}
return
}
err = cc.dec.Decode(v)
if err != nil {
log.Println(log.ERROR, "RPC Client Error decoding response body: ", err)
}
return
}
func (c *InstanceCache) watch() {
for {
select {
case n, ok := <-c.pathNotify:
if !ok {
return
}
uuid := uuidFromPath(n.Path)
switch n.Type {
case PathCacheAddNotification, PathCacheUpdateNotification:
s, err := c.getServiceInfo(uuid)
// err means not all paths exist yet
if err != nil {
continue
}
if _, ok := c.instances[uuid]; ok {
log.Println(log.TRACE, "InstanceCache instance updated:", uuid)
c.instances[uuid] = s
go c.notify(skynet.InstanceUpdated, s)
} else {
log.Println(log.TRACE, "InstanceCache instance added:", uuid)
c.instances[uuid] = s
go c.notify(skynet.InstanceAdded, s)
}
case PathCacheRemoveNotification:
if n.Path == path.Join(InstancesBasePath, uuid) {
if s, ok := c.instances[uuid]; ok {
log.Println(log.TRACE, "InstanceCache instance removed:", uuid)
go c.notify(skynet.InstanceRemoved, s)
delete(c.instances, uuid)
}
}
}
}
}
}
func getIdleTimeout(s skynet.ServiceInfo) time.Duration {
if d, err := config.String(s.Name, s.Version, "client.timeout.idle"); err == nil {
if timeout, err := time.ParseDuration(d); err == nil {
return timeout
}
log.Println(log.ERROR, "Failed to parse client.timeout.idle", err)
}
return config.DefaultIdleTimeout
}
func init() {
timeout := 1 * time.Second
addr := DefaultAddr
log.Println(log.INFO, "In init")
if a, err := config.RawStringDefault("zookeeper.addr"); err == nil {
addr = a
log.Println(log.INFO, "addr", a)
} else {
log.Fatal("Failed to parse Zookeeper addr", err)
}
if t, err := config.RawStringDefault("zookeeper.timeout"); err == nil {
if timeout, err = time.ParseDuration(t); err != nil {
log.Fatal("Failed to parse Zookeeper timeout", err)
}
}
skynet.SetServiceManager(NewZookeeperServiceManager(addr, timeout))
}
/*
Conn.performHandshake Responsible for performing handshake with service
*/
func (c *Conn) performHandshake() (err error) {
var sh skynet.ServiceHandshake
decoder := bsonrpc.NewDecoder(c.conn)
err = decoder.Decode(&sh)
if err != nil {
log.Println(log.ERROR, "Failed to decode ServiceHandshake", err)
c.conn.Close()
return HandshakeFailed
}
if sh.Name != c.serviceName {
log.Println(log.ERROR, "Attempted to send request to incorrect service: "+sh.Name)
return HandshakeFailed
}
ch := skynet.ClientHandshake{}
encoder := bsonrpc.NewEncoder(c.conn)
err = encoder.Encode(ch)
if err != nil {
log.Println(log.ERROR, "Failed to encode ClientHandshake", err)
c.conn.Close()
return HandshakeFailed
}
if !sh.Registered {
log.Println(log.ERROR, "Attempted to send request to unregistered service")
return ServiceUnregistered
}
c.rpcClient = bsonrpc.NewClient(c.conn)
c.clientID = sh.ClientID
return
}
func (d *Decoder) Decode(pv interface{}) (err error) {
var lbuf [4]byte
n, err := d.r.Read(lbuf[:])
if n == 0 {
return io.EOF
}
if n != 4 {
err = fmt.Errorf("Corrupted BSON stream: could only read %d", n)
log.Println(log.ERROR, "Error decoding message (reading length): ", err)
return
}
if err != nil {
log.Println(log.ERROR, "Error decoding message (reading length): ", err)
return
}
length := (int(lbuf[0]) << 0) |
(int(lbuf[1]) << 8) |
(int(lbuf[2]) << 16) |
(int(lbuf[3]) << 24)
buf := make([]byte, length)
copy(buf[0:4], lbuf[:])
n, err = io.ReadFull(d.r, buf[4:])
if err != nil {
log.Println(log.ERROR, "Error decoding message (reading message): ", err)
return
}
if n+4 != length {
err = fmt.Errorf("Expected %d bytes, read %d", length, n)
log.Println(log.ERROR, "Error decoding message (reading message): ", err)
}
err = bson.Unmarshal(buf, pv)
return
}
func (c *InstanceCache) buildInitialCache() {
for _, p := range c.cache.Children() {
uuid := uuidFromPath(p)
s, err := c.getServiceInfo(uuid)
if err != nil {
log.Println(log.WARN, err)
continue
}
c.instances[uuid] = s
}
}
