Persist outbound subscribe packets

client.go

@@ -668,7 +668,6 @@ func (c *client) Subscribe(topic string, qos byte, callback MessageHandler) Toke
 	}
 	sub.Topics = append(sub.Topics, topic)
 	sub.Qoss = append(sub.Qoss, qos)
-	DEBUG.Println(CLI, sub.String())
 
 	if strings.HasPrefix(topic, "$share/") {
 		topic = strings.Join(strings.Split(topic, "/")[2:], "/")
@@ -683,7 +682,31 @@ func (c *client) Subscribe(topic string, qos byte, callback MessageHandler) Toke
 	}
 
 	token.subs = append(token.subs, topic)
-	c.oboundP <- &PacketAndToken{p: sub, t: token}
+
+	if sub.MessageID == 0 {
+		sub.MessageID = c.getID(token)
+		token.messageID = sub.MessageID
+	}
+	DEBUG.Println(CLI, sub.String())
+
+	persistOutbound(c.persist, sub)
+	switch c.connectionStatus() {
+	case connecting:
+		DEBUG.Println(CLI, "storing subscribe message (connecting), topic:", topic)
+	case reconnecting:
+		DEBUG.Println(CLI, "storing subscribe message (reconnecting), topic:", topic)
+	default:
+		DEBUG.Println(CLI, "sending subscribe message, topic:", topic)
+		subscribeWaitTimeout := c.options.WriteTimeout
+		if subscribeWaitTimeout == 0 {
+			subscribeWaitTimeout = time.Second * 30
+		}
+		select {
+		case c.oboundP <- &PacketAndToken{p: sub, t: token}:
+		case <-time.After(subscribeWaitTimeout):
+			token.setError(errors.New("subscribe was broken by timeout"))
+		}
+	}
 	DEBUG.Println(CLI, "exit Subscribe")
 	return token
 }
@@ -711,7 +734,29 @@ func (c *client) SubscribeMultiple(filters map[string]byte, callback MessageHand
 	}
 	token.subs = make([]string, len(sub.Topics))
 	copy(token.subs, sub.Topics)
-	c.oboundP <- &PacketAndToken{p: sub, t: token}
+
+	if sub.MessageID == 0 {
+		sub.MessageID = c.getID(token)
+		token.messageID = sub.MessageID
+	}
+	persistOutbound(c.persist, sub)
+	switch c.connectionStatus() {
+	case connecting:
+		DEBUG.Println(CLI, "storing subscribe message (connecting), topics:", sub.Topics)
+	case reconnecting:
+		DEBUG.Println(CLI, "storing subscribe message (reconnecting), topics:", sub.Topics)
+	default:
+		DEBUG.Println(CLI, "sending subscribe message, topics:", sub.Topics)
+		subscribeWaitTimeout := c.options.WriteTimeout
+		if subscribeWaitTimeout == 0 {
+			subscribeWaitTimeout = time.Second * 30
+		}
+		select {
+		case c.oboundP <- &PacketAndToken{p: sub, t: token}:
+		case <-time.After(subscribeWaitTimeout):
+			token.setError(errors.New("subscribe was broken by timeout"))
+		}
+	}
 	DEBUG.Println(CLI, "exit SubscribeMultiple")
 	return token
 }
@@ -754,7 +799,11 @@ func (c *client) resume(subscription bool) {
 			case *packets.SubscribePacket:
 				if subscription {
 					DEBUG.Println(STR, fmt.Sprintf("loaded pending subscribe (%d)", details.MessageID))
+					subPacket := packet.(*packets.SubscribePacket)
 					token := newToken(packets.Subscribe).(*SubscribeToken)
+					token.messageID = details.MessageID
+					token.subs = append(token.subs, subPacket.Topics...)
+					c.claimID(token, details.MessageID)
 					select {
 					case c.oboundP <- &PacketAndToken{p: packet, t: token}:
 					case <-c.stop:

fvt_client_test.go

@@ -1181,7 +1181,7 @@ func Test_ConnectRetryPublish(t *testing.T) {
 
 	// disconnect and then reconnect with correct server
 	p.Disconnect(250)
-	
+
 	pops = NewClientOptions().AddBroker(FVTTCP).SetClientID("crp-pub").SetCleanSession(false).
 		SetStore(memStore2).SetConnectRetry(true).SetConnectRetryInterval(time.Second / 2)
 	p = NewClient(pops).(*client)
@@ -1198,3 +1198,89 @@ func Test_ConnectRetryPublish(t *testing.T) {
 	s.Disconnect(250)
 	memStore.Close()
 }
+
+func Test_ResumeSubs(t *testing.T) {
+	topic := "/test/ResumeSubs"
+	var qos byte = 1
+	payload := "sample Payload"
+	choke := make(chan bool)
+
+	// subscribe to topic before establishing a connection, and publish a message after the publish client has connected successfully
+	subMemStore := NewMemoryStore()
+	subMemStore.Open()
+	sops := NewClientOptions().AddBroker("256.256.256.256").SetClientID("resumesubs-sub").SetConnectRetry(true).
+		SetConnectRetryInterval(time.Second / 2).SetResumeSubs(true).SetStore(subMemStore)
+
+	s := NewClient(sops)
+	sConnToken := s.Connect()
+
+	subToken := s.Subscribe(topic, qos, nil)
+
+	// Verify the subscribe packet exists in the memorystore
+	ids := subMemStore.All()
+	if len(ids) == 0 {
+		t.Fatalf("Expected subscribe packet to be in store")
+	} else if len(ids) != 1 {
+		t.Fatalf("Expected 1 packet to be in store")
+	}
+	packet := subMemStore.Get(ids[0])
+	if packet == nil {
+		t.Fatal("Failed to retrieve packet from store")
+	}
+	sp, ok := packet.(*packets.SubscribePacket)
+	if !ok {
+		t.Fatalf("Packet in store not of the expected type (%T)", packet)
+	}
+	if len(sp.Topics) != 1 || sp.Topics[0] != topic || len(sp.Qoss) != 1 || sp.Qoss[0] != qos {
+		t.Fatalf("Stored Subscribe Packet contents not as expected (%v, %v)", sp.Topics, sp.Qoss)
+	}
+
+	time.Sleep(time.Second) // Wait a second to ensure we are past SetConnectRetryInterval
+	if sConnToken.Error() != nil {
+		t.Fatalf("Connect returned error (should be retrying) (%v)", sConnToken.Error())
+	}
+	if subToken.Error() != nil {
+		t.Fatalf("Subscribe returned error (should be persisted) (%v)", sConnToken.Error())
+	}
+
+	// test that the stored subscribe packet gets sent to the broker after connecting
+	subMemStore2 := NewMemoryStore()
+	subMemStore2.Open()
+	subMemStore2.Put(ids[0], packet)
+
+	s.Disconnect(250)
+
+	// Connect to broker and test that subscription was resumed
+	sops = NewClientOptions().AddBroker(FVTTCP).SetClientID("resumesubs-sub").
+		SetStore(subMemStore2).SetResumeSubs(true).SetCleanSession(false).SetConnectRetry(true).
+		SetConnectRetryInterval(time.Second / 2)
+
+	var f MessageHandler = func(client Client, msg Message) {
+		if msg.Topic() != topic || string(msg.Payload()) != payload {
+			t.Fatalf("Received unexpected message: %v, %v", msg.Topic(), msg.Payload())
+		}
+		choke <- true
+	}
+	sops.SetDefaultPublishHandler(f)
+	s = NewClient(sops).(*client)
+	if sConnToken = s.Connect(); sConnToken.Wait() && sConnToken.Error() != nil {
+		t.Fatalf("Error on valid subscribe Connect(): %v", sConnToken.Error())
+	}
+
+	// publish message to subscribed topic to verify subscription
+	pops := NewClientOptions().AddBroker(FVTTCP).SetClientID("resumesubs-pub").SetCleanSession(true).
+		SetConnectRetry(true).SetConnectRetryInterval(time.Second / 2)
+	p := NewClient(pops).(*client)
+	if pConnToken := p.Connect(); pConnToken.Wait() && pConnToken.Error() != nil {
+		t.Fatalf("Error on valid Publish.Connect(): %v", pConnToken.Error())
+	}
+
+	if pubToken := p.Publish(topic, 1, false, payload); pubToken.Wait() && pubToken.Error() != nil {
+		t.Fatalf("Error on valid Client.Publish(): %v", pubToken.Error())
+	}
+
+	wait(choke)
+
+	s.Disconnect(250)
+	p.Disconnect(250)
+}

net.go

@@ -178,12 +178,6 @@ func outgoing(c *client) {
 			}
 			DEBUG.Println(NET, "obound wrote msg, id:", msg.MessageID)
 		case msg := <-c.oboundP:
-			switch msg.p.(type) {
-			case *packets.SubscribePacket:
-				msg.p.(*packets.SubscribePacket).MessageID = c.getID(msg.t)
-			case *packets.UnsubscribePacket:
-				msg.p.(*packets.UnsubscribePacket).MessageID = c.getID(msg.t)
-			}
 			DEBUG.Println(NET, "obound priority msg to write, type", reflect.TypeOf(msg.p))
 			if err := msg.p.Write(c.conn); err != nil {
 				ERROR.Println(NET, "outgoing stopped with error", err)

token.go

@@ -160,6 +160,7 @@ type SubscribeToken struct {
 	baseToken
 	subs      []string
 	subResult map[string]byte
+	messageID uint16
 }
 
 // Result returns a map of topics that were subscribed to along with

unit_client_test.go

@@ -104,4 +104,4 @@ func Test_isConnectionOpenNegative(t *testing.T) {
 	if c.IsConnectionOpen() {
 		t.Fail()
 	}
-}
+}