Ignore invalid message ID if last request timed out

[govpp.git] / api / api.go

diff --git a/api/api.go b/api/api.go
index 98932fa..60508cd 100644 (file)
--- a/api/api.go
+++ b/api/api.go
@@ -18,6 +18,8 @@ import (
        "errors"
        "fmt"
        "time"
+
+       "github.com/sirupsen/logrus"
 )
 
 // MessageType represents the type of a VPP message.
@@ -61,7 +63,7 @@ type ChannelProvider interface {
        // It uses default buffer sizes for the request and reply Go channels.
        NewAPIChannel() (*Channel, error)
 
-       // NewAPIChannel returns a new channel for communication with VPP via govpp core.
+       // NewAPIChannelBuffered returns a new channel for communication with VPP via govpp core.
        // It allows to specify custom buffer sizes for the request and reply Go channels.
        NewAPIChannelBuffered() (*Channel, error)
 }
@@ -94,6 +96,7 @@ type Channel struct {
 
        replyTimeout time.Duration // maximum time that the API waits for a reply from VPP before returning an error, can be set with SetReplyTimeout
        metadata     interface{}   // opaque metadata of the API channel
+       lastTimedOut bool          // wether last request timed out
 }
 
 // VppRequest is a request that will be sent to VPP.
@@ -214,34 +217,46 @@ func (ch *Channel) receiveReplyInternal(msg Message) (LastReplyReceived bool, er
        if msg == nil {
                return false, errors.New("nil message passed in")
        }
-       select {
-       // blocks until a reply comes to ReplyChan or until timeout expires
-       case vppReply := <-ch.ReplyChan:
-               if vppReply.Error != nil {
-                       err = vppReply.Error
-                       return
-               }
-               if vppReply.LastReplyReceived {
-                       LastReplyReceived = true
-                       return
-               }
-               // message checks
-               expMsgID, err := ch.MsgIdentifier.GetMessageID(msg)
-               if err != nil {
-                       err = fmt.Errorf("message %s with CRC %s is not compatible with the VPP we are connected to",
-                               msg.GetMessageName(), msg.GetCrcString())
+
+       timer := time.NewTimer(ch.replyTimeout)
+       for {
+               select {
+               // blocks until a reply comes to ReplyChan or until timeout expires
+               case vppReply := <-ch.ReplyChan:
+                       if vppReply.Error != nil {
+                               err = vppReply.Error
+                               return
+                       }
+                       if vppReply.LastReplyReceived {
+                               LastReplyReceived = true
+                               return
+                       }
+                       // message checks
+                       expMsgID, err := ch.MsgIdentifier.GetMessageID(msg)
+                       if err != nil {
+                               err = fmt.Errorf("message %s with CRC %s is not compatible with the VPP we are connected to",
+                                       msg.GetMessageName(), msg.GetCrcString())
+                               return false, err
+                       }
+                       if vppReply.MessageID != expMsgID {
+                               if ch.lastTimedOut {
+                                       logrus.Warnf("received invalid message ID, expected %d (%s), but got %d (probably timed out reply from previous request)",
+                                               expMsgID, msg.GetMessageName(), vppReply.MessageID)
+                                       continue
+                               }
+                               err = fmt.Errorf("received invalid message ID, expected %d (%s), but got %d (check if multiple goroutines are not sharing single GoVPP channel)",
+                                       expMsgID, msg.GetMessageName(), vppReply.MessageID)
+                               return false, err
+                       }
+                       ch.lastTimedOut = false
+                       // decode the message
+                       err = ch.MsgDecoder.DecodeMsg(vppReply.Data, msg)
                        return false, err
-               }
-               if vppReply.MessageID != expMsgID {
-                       err = fmt.Errorf("received invalid message ID, expected %d (%s), but got %d (check if multiple goroutines are not sharing single GoVPP channel)",
-                               expMsgID, msg.GetMessageName(), vppReply.MessageID)
+               case <-timer.C:
+                       ch.lastTimedOut = true
+                       err = fmt.Errorf("no reply received within the timeout period %s", ch.replyTimeout)
                        return false, err
                }
-               // decode the message
-               err = ch.MsgDecoder.DecodeMsg(vppReply.Data, msg)
-
-       case <-time.After(ch.replyTimeout):
-               err = fmt.Errorf("no reply received within the timeout period %s", ch.replyTimeout)
        }
        return
 }