import (
"errors"
"fmt"
+ "path"
"reflect"
"sync"
"sync/atomic"
"git.fd.io/govpp.git/codec"
)
+const (
+ DefaultReconnectInterval = time.Second / 2 // default interval between reconnect attempts
+ DefaultMaxReconnectAttempts = 3 // default maximum number of reconnect attempts
+)
+
var (
RequestChanBufSize = 100 // default size of the request channel buffer
ReplyChanBufSize = 100 // default size of the reply channel buffer
)
var (
- HealthCheckProbeInterval = time.Second * 1 // default health check probe interval
- HealthCheckReplyTimeout = time.Millisecond * 100 // timeout for reply to a health check probe
- HealthCheckThreshold = 1 // number of failed health checks until the error is reported
- DefaultReplyTimeout = time.Second * 1 // default timeout for replies from VPP
+ HealthCheckProbeInterval = time.Second // default health check probe interval
+ HealthCheckReplyTimeout = time.Millisecond * 250 // timeout for reply to a health check probe
+ HealthCheckThreshold = 2 // number of failed health checks until the error is reported
+ DefaultReplyTimeout = time.Second // default timeout for replies from VPP
)
// ConnectionState represents the current state of the connection to VPP.
// Connected represents state in which the connection has been successfully established.
Connected ConnectionState = iota
- // Disconnected represents state in which the connection has been dropped.
+ // NotResponding represents a state where the VPP socket accepts messages but replies are received with delay,
+ // or not at all. GoVPP treats this state internally the same as disconnected.
+ NotResponding
+
+ // Disconnected represents state in which the VPP socket is closed and the connection is considered dropped.
Disconnected
+
+ // Failed represents state in which the reconnecting failed after exceeding maximum number of attempts.
+ Failed
)
+func (s ConnectionState) String() string {
+ switch s {
+ case Connected:
+ return "Connected"
+ case NotResponding:
+ return "NotResponding"
+ case Disconnected:
+ return "Disconnected"
+ case Failed:
+ return "Failed"
+ default:
+ return fmt.Sprintf("UnknownState(%d)", s)
+ }
+}
+
// ConnectionEvent is a notification about change in the VPP connection state.
type ConnectionEvent struct {
// Timestamp holds the time when the event has been created.
// Connection represents a shared memory connection to VPP via vppAdapter.
type Connection struct {
- vppClient adapter.VppAPI // VPP binary API client adapter
+ vppClient adapter.VppAPI // VPP binary API client
+
+ maxAttempts int // interval for reconnect attempts
+ recInterval time.Duration // maximum number of reconnect attempts
vppConnected uint32 // non-zero if the adapter is connected to VPP
- codec *codec.MsgCodec // message codec
- msgIDs map[string]uint16 // map of message IDs indexed by message name + CRC
- msgMap map[uint16]api.Message // map of messages indexed by message ID
+ connChan chan ConnectionEvent // connection status events are sent to this channel
+
+ codec MessageCodec // message codec
+ msgIDs map[string]uint16 // map of message IDs indexed by message name + CRC
+ msgMapByPath map[string]map[uint16]api.Message // map of messages indexed by message ID which are indexed by path
maxChannelID uint32 // maximum used channel ID (the real limit is 2^15, 32-bit is used for atomic operations)
channelsLock sync.RWMutex // lock for the channels map
lastReplyLock sync.Mutex // lock for the last reply
lastReply time.Time // time of the last received reply from VPP
+
+ msgControlPing api.Message
+ msgControlPingReply api.Message
+
+ apiTrace *trace // API tracer (disabled by default)
}
-func newConnection(binapi adapter.VppAPI) *Connection {
+func newConnection(binapi adapter.VppAPI, attempts int, interval time.Duration) *Connection {
+ if attempts == 0 {
+ attempts = DefaultMaxReconnectAttempts
+ }
+ if interval == 0 {
+ interval = DefaultReconnectInterval
+ }
+
c := &Connection{
- vppClient: binapi,
- codec: &codec.MsgCodec{},
- msgIDs: make(map[string]uint16),
- msgMap: make(map[uint16]api.Message),
- channels: make(map[uint16]*Channel),
- subscriptions: make(map[uint16][]*subscriptionCtx),
+ vppClient: binapi,
+ maxAttempts: attempts,
+ recInterval: interval,
+ connChan: make(chan ConnectionEvent, NotificationChanBufSize),
+ codec: codec.DefaultCodec,
+ msgIDs: make(map[string]uint16),
+ msgMapByPath: make(map[string]map[uint16]api.Message),
+ channels: make(map[uint16]*Channel),
+ subscriptions: make(map[uint16][]*subscriptionCtx),
+ msgControlPing: msgControlPing,
+ msgControlPingReply: msgControlPingReply,
+ apiTrace: &trace{
+ list: make([]*api.Record, 0),
+ mux: &sync.Mutex{},
+ },
}
binapi.SetMsgCallback(c.msgCallback)
return c
}
-// Connect connects to VPP using specified VPP adapter and returns the connection handle.
-// This call blocks until VPP is connected, or an error occurs. Only one connection attempt will be performed.
+// Connect connects to VPP API using specified adapter and returns a connection handle.
+// This call blocks until it is either connected, or an error occurs.
+// Only one connection attempt will be performed.
func Connect(binapi adapter.VppAPI) (*Connection, error) {
// create new connection handle
- c := newConnection(binapi)
+ c := newConnection(binapi, DefaultMaxReconnectAttempts, DefaultReconnectInterval)
// blocking attempt to connect to VPP
if err := c.connectVPP(); err != nil {
// and ConnectionState channel. This call does not block until connection is established, it
// returns immediately. The caller is supposed to watch the returned ConnectionState channel for
// Connected/Disconnected events. In case of disconnect, the library will asynchronously try to reconnect.
-func AsyncConnect(binapi adapter.VppAPI) (*Connection, chan ConnectionEvent, error) {
+func AsyncConnect(binapi adapter.VppAPI, attempts int, interval time.Duration) (*Connection, chan ConnectionEvent, error) {
// create new connection handle
- c := newConnection(binapi)
+ c := newConnection(binapi, attempts, interval)
// asynchronously attempt to connect to VPP
- connChan := make(chan ConnectionEvent, NotificationChanBufSize)
- go c.connectLoop(connChan)
+ go c.connectLoop()
- return c, connChan, nil
+ return c, c.connChan, nil
}
// connectVPP performs blocking attempt to connect to VPP.
if err := c.vppClient.Connect(); err != nil {
return err
}
-
- log.Debugf("Connected to VPP.")
+ log.Debugf("Connected to VPP")
if err := c.retrieveMessageIDs(); err != nil {
- c.vppClient.Disconnect()
+ if err := c.vppClient.Disconnect(); err != nil {
+ log.Debugf("disconnecting vpp client failed: %v", err)
+ }
return fmt.Errorf("VPP is incompatible: %v", err)
}
return nil
}
-// Disconnect disconnects from VPP and releases all connection-related resources.
+// Disconnect disconnects from VPP API and releases all connection-related resources.
func (c *Connection) Disconnect() {
if c == nil {
return
}
-
if c.vppClient != nil {
c.disconnectVPP()
}
// disconnectVPP disconnects from VPP in case it is connected.
func (c *Connection) disconnectVPP() {
if atomic.CompareAndSwapUint32(&c.vppConnected, 1, 0) {
- c.vppClient.Disconnect()
+ log.Debug("Disconnecting from VPP..")
+
+ if err := c.vppClient.Disconnect(); err != nil {
+ log.Debugf("Disconnect from VPP failed: %v", err)
+ }
+ log.Debug("Disconnected from VPP")
}
}
c.channelsLock.Unlock()
}
-// GetMessageID returns message identifier of given API message.
-func (c *Connection) GetMessageID(msg api.Message) (uint16, error) {
- if c == nil {
- return 0, errors.New("nil connection passed in")
- }
-
- if msgID, ok := c.msgIDs[getMsgNameWithCrc(msg)]; ok {
- return msgID, nil
- }
-
- return 0, fmt.Errorf("unknown message: %s (%s)", msg.GetMessageName(), msg.GetCrcString())
-}
-
-// LookupByID looks up message name and crc by ID.
-func (c *Connection) LookupByID(msgID uint16) (api.Message, error) {
- if c == nil {
- return nil, errors.New("nil connection passed in")
- }
-
- if msg, ok := c.msgMap[msgID]; ok {
- return msg, nil
- }
-
- return nil, fmt.Errorf("unknown message ID: %d", msgID)
-}
-
-// retrieveMessageIDs retrieves IDs for all registered messages and stores them in map
-func (c *Connection) retrieveMessageIDs() (err error) {
- t := time.Now()
-
- var addMsg = func(msgID uint16, msg api.Message) {
- c.msgIDs[getMsgNameWithCrc(msg)] = msgID
- c.msgMap[msgID] = msg
- }
-
- msgs := api.GetRegisteredMessages()
-
- for name, msg := range msgs {
- msgID, err := c.vppClient.GetMsgID(msg.GetMessageName(), msg.GetCrcString())
- if err != nil {
- return err
- }
-
- addMsg(msgID, msg)
-
- if msg.GetMessageName() == msgControlPing.GetMessageName() {
- c.pingReqID = msgID
- msgControlPing = reflect.New(reflect.TypeOf(msg).Elem()).Interface().(api.Message)
- } else if msg.GetMessageName() == msgControlPingReply.GetMessageName() {
- c.pingReplyID = msgID
- msgControlPingReply = reflect.New(reflect.TypeOf(msg).Elem()).Interface().(api.Message)
- }
-
- if debugMsgIDs {
- log.Debugf("message %q (%s) has ID: %d", name, getMsgNameWithCrc(msg), msgID)
- }
- }
-
- log.Debugf("retrieving %d message IDs took %s", len(msgs), time.Since(t))
-
- // fallback for control ping when vpe package is not imported
- if c.pingReqID == 0 {
- c.pingReqID, err = c.vppClient.GetMsgID(msgControlPing.GetMessageName(), msgControlPing.GetCrcString())
- if err != nil {
- return err
- }
- addMsg(c.pingReqID, msgControlPing)
- }
- if c.pingReplyID == 0 {
- c.pingReplyID, err = c.vppClient.GetMsgID(msgControlPingReply.GetMessageName(), msgControlPingReply.GetCrcString())
- if err != nil {
- return err
- }
- addMsg(c.pingReplyID, msgControlPingReply)
- }
-
- return nil
-}
-
// connectLoop attempts to connect to VPP until it succeeds.
// Then it continues with healthCheckLoop.
-func (c *Connection) connectLoop(connChan chan ConnectionEvent) {
+func (c *Connection) connectLoop() {
+ var reconnectAttempts int
+
// loop until connected
for {
if err := c.vppClient.WaitReady(); err != nil {
- log.Warnf("wait ready failed: %v", err)
+ log.Debugf("wait ready failed: %v", err)
}
if err := c.connectVPP(); err == nil {
// signal connected event
- connChan <- ConnectionEvent{Timestamp: time.Now(), State: Connected}
+ c.sendConnEvent(ConnectionEvent{Timestamp: time.Now(), State: Connected})
break
+ } else if reconnectAttempts < c.maxAttempts {
+ reconnectAttempts++
+ log.Warnf("connecting failed (attempt %d/%d): %v", reconnectAttempts, c.maxAttempts, err)
+ time.Sleep(c.recInterval)
} else {
- log.Errorf("connecting to VPP failed: %v", err)
- time.Sleep(time.Second)
+ c.sendConnEvent(ConnectionEvent{Timestamp: time.Now(), State: Failed, Error: err})
+ return
}
}
// we are now connected, continue with health check loop
- c.healthCheckLoop(connChan)
+ c.healthCheckLoop()
}
// healthCheckLoop checks whether connection to VPP is alive. In case of disconnect,
// it continues with connectLoop and tries to reconnect.
-func (c *Connection) healthCheckLoop(connChan chan ConnectionEvent) {
+func (c *Connection) healthCheckLoop() {
// create a separate API channel for health check probes
ch, err := c.newAPIChannel(1, 1)
if err != nil {
}
// send the control ping request
- ch.reqChan <- &vppRequest{msg: msgControlPing}
+ ch.reqChan <- &vppRequest{msg: c.msgControlPing}
for {
// expect response within timeout period
failedChecks++
log.Warnf("VPP health check probe timed out after %v (%d. timeout)", HealthCheckReplyTimeout, failedChecks)
if failedChecks > HealthCheckThreshold {
- // in case of exceeded failed check treshold, assume VPP disconnected
- log.Errorf("VPP health check exceeded treshold for timeouts (>%d), assuming disconnect", HealthCheckThreshold)
- connChan <- ConnectionEvent{Timestamp: time.Now(), State: Disconnected}
+ // in case of exceeded failed check threshold, assume VPP unresponsive
+ log.Errorf("VPP does not responding, the health check exceeded threshold for timeouts (>%d)", HealthCheckThreshold)
+ c.sendConnEvent(ConnectionEvent{Timestamp: time.Now(), State: NotResponding})
break
}
} else if err != nil {
// in case of error, assume VPP disconnected
log.Errorf("VPP health check probe failed: %v", err)
- connChan <- ConnectionEvent{Timestamp: time.Now(), State: Disconnected, Error: err}
+ c.sendConnEvent(ConnectionEvent{Timestamp: time.Now(), State: Disconnected, Error: err})
break
} else if failedChecks > 0 {
// in case of success after failed checks, clear failed check counter
c.disconnectVPP()
// we are now disconnected, start connect loop
- c.connectLoop(connChan)
+ c.connectLoop()
}
func getMsgNameWithCrc(x api.Message) string {
- return x.GetMessageName() + "_" + x.GetCrcString()
+ return getMsgID(x.GetMessageName(), x.GetCrcString())
+}
+
+func getMsgID(name, crc string) string {
+ return name + "_" + crc
+}
+
+func getMsgFactory(msg api.Message) func() api.Message {
+ return func() api.Message {
+ return reflect.New(reflect.TypeOf(msg).Elem()).Interface().(api.Message)
+ }
+}
+
+// GetMessageID returns message identifier of given API message.
+func (c *Connection) GetMessageID(msg api.Message) (uint16, error) {
+ if c == nil {
+ return 0, errors.New("nil connection passed in")
+ }
+ pkgPath := c.GetMessagePath(msg)
+ msgID, err := c.vppClient.GetMsgID(msg.GetMessageName(), msg.GetCrcString())
+ if err != nil {
+ return 0, err
+ }
+ if pathMsgs, pathOk := c.msgMapByPath[pkgPath]; !pathOk {
+ c.msgMapByPath[pkgPath] = make(map[uint16]api.Message)
+ c.msgMapByPath[pkgPath][msgID] = msg
+ } else if _, msgOk := pathMsgs[msgID]; !msgOk {
+ c.msgMapByPath[pkgPath][msgID] = msg
+ }
+ if _, ok := c.msgIDs[getMsgNameWithCrc(msg)]; ok {
+ return msgID, nil
+ }
+ c.msgIDs[getMsgNameWithCrc(msg)] = msgID
+ return msgID, nil
+}
+
+// LookupByID looks up message name and crc by ID.
+func (c *Connection) LookupByID(path string, msgID uint16) (api.Message, error) {
+ if c == nil {
+ return nil, errors.New("nil connection passed in")
+ }
+ if msg, ok := c.msgMapByPath[path][msgID]; ok {
+ return msg, nil
+ }
+ return nil, fmt.Errorf("unknown message ID %d for path '%s'", msgID, path)
+}
+
+// GetMessagePath returns path for the given message
+func (c *Connection) GetMessagePath(msg api.Message) string {
+ return path.Dir(reflect.TypeOf(msg).Elem().PkgPath())
+}
+
+// retrieveMessageIDs retrieves IDs for all registered messages and stores them in map
+func (c *Connection) retrieveMessageIDs() (err error) {
+ t := time.Now()
+
+ msgsByPath := api.GetRegisteredMessages()
+
+ var n int
+ for pkgPath, msgs := range msgsByPath {
+ for _, msg := range msgs {
+ msgID, err := c.GetMessageID(msg)
+ if err != nil {
+ if debugMsgIDs {
+ log.Debugf("retrieving message ID for %s.%s failed: %v",
+ pkgPath, msg.GetMessageName(), err)
+ }
+ continue
+ }
+ n++
+
+ if c.pingReqID == 0 && msg.GetMessageName() == c.msgControlPing.GetMessageName() {
+ c.pingReqID = msgID
+ c.msgControlPing = reflect.New(reflect.TypeOf(msg).Elem()).Interface().(api.Message)
+ } else if c.pingReplyID == 0 && msg.GetMessageName() == c.msgControlPingReply.GetMessageName() {
+ c.pingReplyID = msgID
+ c.msgControlPingReply = reflect.New(reflect.TypeOf(msg).Elem()).Interface().(api.Message)
+ }
+
+ if debugMsgIDs {
+ log.Debugf("message %q (%s) has ID: %d", msg.GetMessageName(), getMsgNameWithCrc(msg), msgID)
+ }
+ }
+ log.WithField("took", time.Since(t)).
+ Debugf("retrieved IDs for %d messages (registered %d) from path %s", n, len(msgs), pkgPath)
+ }
+
+ return nil
+}
+
+func (c *Connection) sendConnEvent(event ConnectionEvent) {
+ select {
+ case c.connChan <- event:
+ default:
+ log.Warn("Connection state channel is full, discarding value.")
+ }
+}
+
+// Trace gives access to the API trace interface
+func (c *Connection) Trace() api.Trace {
+ return c.apiTrace
+}
+
+// trace records api message
+func (c *Connection) trace(msg api.Message, chId uint16, t time.Time, isReceived bool) {
+ if atomic.LoadInt32(&c.apiTrace.isEnabled) == 0 {
+ return
+ }
+ entry := &api.Record{
+ Message: msg,
+ Timestamp: t,
+ IsReceived: isReceived,
+ ChannelID: chId,
+ }
+ c.apiTrace.mux.Lock()
+ c.apiTrace.list = append(c.apiTrace.list, entry)
+ c.apiTrace.mux.Unlock()
}
Code Review / govpp.git / blobdiff