Decode message context using the message type only
[govpp.git] / core / request_handler.go
index fd6d100..29685f6 100644 (file)
@@ -21,15 +21,19 @@ import (
        "time"
 
        logger "github.com/sirupsen/logrus"
+
+       "git.fd.io/govpp.git/api"
 )
 
+var ReplyChannelTimeout = time.Millisecond * 100
+
 var (
        ErrNotConnected = errors.New("not connected to VPP, ignoring the request")
        ErrProbeTimeout = errors.New("probe reply not received within timeout period")
 )
 
 // watchRequests watches for requests on the request API channel and forwards them as messages to VPP.
-func (c *Connection) watchRequests(ch *channel) {
+func (c *Connection) watchRequests(ch *Channel) {
        for {
                select {
                case req, ok := <-ch.reqChan:
@@ -39,97 +43,157 @@ func (c *Connection) watchRequests(ch *channel) {
                                c.releaseAPIChannel(ch)
                                return
                        }
-                       c.processRequest(ch, req)
-
-               case req := <-ch.notifSubsChan:
-                       // new request on the notification subscribe channel
-                       c.processSubscriptionRequest(ch, req)
+                       if err := c.processRequest(ch, req); err != nil {
+                               sendReply(ch, &vppReply{
+                                       seqNum: req.seqNum,
+                                       err:    fmt.Errorf("unable to process request: %w", err),
+                               })
+                       }
                }
        }
 }
 
 // processRequest processes a single request received on the request channel.
-func (c *Connection) processRequest(ch *channel, req *vppRequest) error {
+func (c *Connection) sendMessage(context uint32, msg api.Message) error {
+       // check whether we are connected to VPP
+       if atomic.LoadUint32(&c.vppConnected) == 0 {
+               return ErrNotConnected
+       }
+
+       /*log := log.WithFields(logger.Fields{
+               "context":  context,
+               "msg_name": msg.GetMessageName(),
+               "msg_crc":  msg.GetCrcString(),
+       })*/
+
+       // retrieve message ID
+       msgID, err := c.GetMessageID(msg)
+       if err != nil {
+               //log.WithError(err).Debugf("unable to retrieve message ID: %#v", msg)
+               return err
+       }
+
+       //log = log.WithField("msg_id", msgID)
+
+       // encode the message
+       data, err := c.codec.EncodeMsg(msg, msgID)
+       if err != nil {
+               log.WithError(err).Debugf("unable to encode message: %#v", msg)
+               return err
+       }
+
+       //log = log.WithField("msg_length", len(data))
+
+       if log.Level >= logger.DebugLevel {
+               log.Debugf("--> SEND: MSG %T %+v", msg, msg)
+       }
+
+       // send message to VPP
+       err = c.vppClient.SendMsg(context, data)
+       if err != nil {
+               log.WithError(err).Debugf("unable to send message: %#v", msg)
+               return err
+       }
+
+       return nil
+}
+
+// processRequest processes a single request received on the request channel.
+func (c *Connection) processRequest(ch *Channel, req *vppRequest) error {
        // check whether we are connected to VPP
-       if atomic.LoadUint32(&c.connected) == 0 {
+       if atomic.LoadUint32(&c.vppConnected) == 0 {
                err := ErrNotConnected
-               log.Errorf("processing request failed: %v", err)
-               sendReplyError(ch, req, err)
+               log.WithFields(logger.Fields{
+                       "channel":  ch.id,
+                       "seq_num":  req.seqNum,
+                       "msg_name": req.msg.GetMessageName(),
+                       "msg_crc":  req.msg.GetCrcString(),
+                       "error":    err,
+               }).Warnf("Unable to process request")
                return err
        }
 
        // retrieve message ID
        msgID, err := c.GetMessageID(req.msg)
        if err != nil {
-               err = fmt.Errorf("unable to retrieve message ID: %v", err)
                log.WithFields(logger.Fields{
+                       "channel":  ch.id,
                        "msg_name": req.msg.GetMessageName(),
                        "msg_crc":  req.msg.GetCrcString(),
                        "seq_num":  req.seqNum,
-               }).Error(err)
-               sendReplyError(ch, req, err)
+                       "error":    err,
+               }).Warnf("Unable to retrieve message ID")
                return err
        }
 
        // encode the message into binary
        data, err := c.codec.EncodeMsg(req.msg, msgID)
        if err != nil {
-               err = fmt.Errorf("unable to encode the messge: %v", err)
                log.WithFields(logger.Fields{
                        "channel":  ch.id,
                        "msg_id":   msgID,
                        "msg_name": req.msg.GetMessageName(),
+                       "msg_crc":  req.msg.GetCrcString(),
                        "seq_num":  req.seqNum,
-               }).Error(err)
-               sendReplyError(ch, req, err)
+                       "error":    err,
+               }).Warnf("Unable to encode message: %T %+v", req.msg, req.msg)
                return err
        }
 
-       // get context
        context := packRequestContext(ch.id, req.multi, req.seqNum)
-       if log.Level == logger.DebugLevel { // for performance reasons - logrus does some processing even if debugs are disabled
+
+       if log.Level >= logger.DebugLevel { // for performance reasons - logrus does some processing even if debugs are disabled
                log.WithFields(logger.Fields{
                        "channel":  ch.id,
-                       "context":  context,
-                       "is_multi": req.multi,
                        "msg_id":   msgID,
                        "msg_name": req.msg.GetMessageName(),
-                       "msg_size": len(data),
+                       "msg_crc":  req.msg.GetCrcString(),
                        "seq_num":  req.seqNum,
-               }).Debug(" -> Sending a message to VPP.")
+                       "is_multi": req.multi,
+                       "context":  context,
+                       "data_len": len(data),
+               }).Debugf("--> SEND MSG: %T %+v", req.msg, req.msg)
        }
 
        // send the request to VPP
-       err = c.vpp.SendMsg(context, data)
+       err = c.vppClient.SendMsg(context, data)
        if err != nil {
-               err = fmt.Errorf("unable to send the message: %v", err)
                log.WithFields(logger.Fields{
-                       "context": context,
-                       "msg_id":  msgID,
-                       "seq_num": req.seqNum,
-               }).Error(err)
-               sendReplyError(ch, req, err)
+                       "channel":  ch.id,
+                       "msg_id":   msgID,
+                       "msg_name": req.msg.GetMessageName(),
+                       "msg_crc":  req.msg.GetCrcString(),
+                       "seq_num":  req.seqNum,
+                       "is_multi": req.multi,
+                       "context":  context,
+                       "data_len": len(data),
+                       "error":    err,
+               }).Warnf("Unable to send message")
                return err
        }
 
        if req.multi {
                // send a control ping to determine end of the multipart response
-               pingData, _ := c.codec.EncodeMsg(msgControlPing, c.pingReqID)
+               pingData, _ := c.codec.EncodeMsg(c.msgControlPing, c.pingReqID)
 
-               log.WithFields(logger.Fields{
-                       "channel":  ch.id,
-                       "context":  context,
-                       "msg_id":   c.pingReqID,
-                       "msg_size": len(pingData),
-                       "seq_num":  req.seqNum,
-               }).Debug(" -> Sending a control ping to VPP.")
+               if log.Level >= logger.DebugLevel {
+                       log.WithFields(logger.Fields{
+                               "channel":  ch.id,
+                               "msg_id":   c.pingReqID,
+                               "msg_name": c.msgControlPing.GetMessageName(),
+                               "msg_crc":  c.msgControlPing.GetCrcString(),
+                               "seq_num":  req.seqNum,
+                               "context":  context,
+                               "data_len": len(pingData),
+                       }).Debugf(" -> SEND MSG: %T", c.msgControlPing)
+               }
 
-               if err := c.vpp.SendMsg(context, pingData); err != nil {
+               if err := c.vppClient.SendMsg(context, pingData); err != nil {
                        log.WithFields(logger.Fields{
                                "context": context,
-                               "msg_id":  msgID,
                                "seq_num": req.seqNum,
-                       }).Warnf("unable to send control ping: %v", err)
+                               "error":   err,
+                       }).Warnf("unable to send control ping")
                }
        }
 
@@ -137,18 +201,17 @@ func (c *Connection) processRequest(ch *channel, req *vppRequest) error {
 }
 
 // msgCallback is called whenever any binary API message comes from VPP.
-func (c *Connection) msgCallback(msgID uint16, context uint32, data []byte) {
-       connLock.RLock()
-       defer connLock.RUnlock()
-
+func (c *Connection) msgCallback(msgID uint16, data []byte) {
        if c == nil {
-               log.Warn("Already disconnected, ignoring the message.")
+               log.WithField(
+                       "msg_id", msgID,
+               ).Warn("Connection already disconnected, ignoring the message.")
                return
        }
 
-       msg, ok := c.msgMap[msgID]
-       if !ok {
-               log.Warnf("Unknown message received, ID: %d", msgID)
+       msgType, name, crc, err := c.getMessageDataByID(msgID)
+       if err != nil {
+               log.Warnln(err)
                return
        }
 
@@ -157,27 +220,24 @@ func (c *Connection) msgCallback(msgID uint16, context uint32, data []byte) {
        // - replies that don't have context as first field (comes as zero)
        // - events that don't have context at all (comes as non zero)
        //
-       msgContext, err := c.codec.DecodeMsgContext(data, msg)
-       if err == nil {
-               if context != msgContext {
-                       log.Debugf("different context was decoded from message (%d -> %d)", context, msgContext)
-                       context = msgContext
-               }
-       } else {
-               log.Errorf("decoding context failed: %v", err)
+       context, err := c.codec.DecodeMsgContext(data, msgType)
+       if err != nil {
+               log.WithField("msg_id", msgID).Warnf("Unable to decode message context: %v", err)
+               return
        }
 
        chanID, isMulti, seqNum := unpackRequestContext(context)
+
        if log.Level == logger.DebugLevel { // for performance reasons - logrus does some processing even if debugs are disabled
                log.WithFields(logger.Fields{
                        "context":  context,
                        "msg_id":   msgID,
-                       "msg_name": msg.GetMessageName(),
                        "msg_size": len(data),
                        "channel":  chanID,
                        "is_multi": isMulti,
                        "seq_num":  seqNum,
-               }).Debug(" <- Received a message from VPP.")
+                       "msg_crc":  crc,
+               }).Debugf("<-- govpp RECEIVE: %s %+v", name)
        }
 
        if context == 0 || c.isNotificationMessage(msgID) {
@@ -202,11 +262,12 @@ func (c *Connection) msgCallback(msgID uint16, context uint32, data []byte) {
        // treat this as a last part of the reply
        lastReplyReceived := isMulti && msgID == c.pingReplyID
 
-       // send the data to the channel
+       // send the data to the channel, it needs to be copied,
+       // because it will be freed after this function returns
        sendReply(ch, &vppReply{
                msgID:        msgID,
                seqNum:       seqNum,
-               data:         data,
+               data:         append([]byte(nil), data...),
                lastReceived: lastReplyReceived,
        })
 
@@ -218,22 +279,94 @@ func (c *Connection) msgCallback(msgID uint16, context uint32, data []byte) {
 
 // sendReply sends the reply into the go channel, if it cannot be completed without blocking, otherwise
 // it logs the error and do not send the message.
-func sendReply(ch *channel, reply *vppReply) {
+func sendReply(ch *Channel, reply *vppReply) {
+       // first try to avoid creating timer
+       select {
+       case ch.replyChan <- reply:
+               return // reply sent ok
+       default:
+               // reply channel full
+       }
+       if ch.receiveReplyTimeout == 0 {
+               log.WithFields(logger.Fields{
+                       "channel": ch.id,
+                       "msg_id":  reply.msgID,
+                       "seq_num": reply.seqNum,
+                       "err":     reply.err,
+               }).Warn("Reply channel full, dropping reply.")
+               return
+       }
        select {
        case ch.replyChan <- reply:
-               // reply sent successfully
-       case <-time.After(time.Millisecond * 100):
+               return // reply sent ok
+       case <-time.After(ch.receiveReplyTimeout):
                // receiver still not ready
                log.WithFields(logger.Fields{
-                       "channel": ch,
+                       "channel": ch.id,
                        "msg_id":  reply.msgID,
                        "seq_num": reply.seqNum,
-               }).Warn("Unable to send the reply, reciever end not ready.")
+                       "err":     reply.err,
+               }).Warnf("Unable to send reply (reciever end not ready in %v).", ch.receiveReplyTimeout)
        }
 }
 
-func sendReplyError(ch *channel, req *vppRequest, err error) {
-       sendReply(ch, &vppReply{seqNum: req.seqNum, err: err})
+// isNotificationMessage returns true if someone has subscribed to provided message ID.
+func (c *Connection) isNotificationMessage(msgID uint16) bool {
+       c.subscriptionsLock.RLock()
+       defer c.subscriptionsLock.RUnlock()
+
+       _, exists := c.subscriptions[msgID]
+       return exists
+}
+
+// sendNotifications send a notification message to all subscribers subscribed for that message.
+func (c *Connection) sendNotifications(msgID uint16, data []byte) {
+       c.subscriptionsLock.RLock()
+       defer c.subscriptionsLock.RUnlock()
+
+       matched := false
+
+       // send to notification to each subscriber
+       for _, sub := range c.subscriptions[msgID] {
+               log.WithFields(logger.Fields{
+                       "msg_name": sub.event.GetMessageName(),
+                       "msg_id":   msgID,
+                       "msg_size": len(data),
+               }).Debug("Sending a notification to the subscription channel.")
+
+               event := sub.msgFactory()
+               if err := c.codec.DecodeMsg(data, event); err != nil {
+                       log.WithFields(logger.Fields{
+                               "msg_name": sub.event.GetMessageName(),
+                               "msg_id":   msgID,
+                               "msg_size": len(data),
+                               "error":    err,
+                       }).Warnf("Unable to decode the notification message")
+                       continue
+               }
+
+               // send the message into the go channel of the subscription
+               select {
+               case sub.notifChan <- event:
+                       // message sent successfully
+               default:
+                       // unable to write into the channel without blocking
+                       log.WithFields(logger.Fields{
+                               "msg_name": sub.event.GetMessageName(),
+                               "msg_id":   msgID,
+                               "msg_size": len(data),
+                       }).Warn("Unable to deliver the notification, reciever end not ready.")
+               }
+
+               matched = true
+       }
+
+       if !matched {
+               log.WithFields(logger.Fields{
+                       "msg_id":   msgID,
+                       "msg_size": len(data),
+               }).Info("No subscription found for the notification message.")
+       }
 }
 
 // +------------------+-------------------+-----------------------+
@@ -277,3 +410,13 @@ func compareSeqNumbers(seqNum1, seqNum2 uint16) int {
        }
        return 1
 }
+
+// Returns message data based on the message ID not depending on the message path
+func (c *Connection) getMessageDataByID(msgID uint16) (typ api.MessageType, name, crc string, err error) {
+       for _, msgs := range c.msgMapByPath {
+               if msg, ok := msgs[msgID]; ok {
+                       return msg.GetMessageType(), msg.GetMessageName(), msg.GetCrcString(), nil
+               }
+       }
+       return typ, name, crc, fmt.Errorf("unknown message received, ID: %d", msgID)
+}