[ADDED] MQTT: allow custom timeout for JS API calls

server/mqtt.go

@@ -189,6 +189,7 @@ const (
 	mqttProcessSubTooLong       = 100 * time.Millisecond
 	mqttDefaultRetainedCacheTTL = 2 * time.Minute
 	mqttRetainedTransferTimeout = 10 * time.Second
+	mqttDefaultJSAPITimeout     = 5 * time.Second
 )
 
 const (
@@ -209,30 +210,30 @@ var (
 	mqttOldProtoName     = []byte("MQIsdp")
 	mqttSessJailDur      = mqttSessFlappingJailDur
 	mqttFlapCleanItvl    = mqttSessFlappingCleanupInterval
-	mqttJSAPITimeout     = 4 * time.Second
 	mqttRetainedCacheTTL = mqttDefaultRetainedCacheTTL
 )
 
 var (
-	errMQTTNotWebsocketPort         = errors.New("MQTT clients over websocket must connect to the Websocket port, not the MQTT port")
-	errMQTTTopicFilterCannotBeEmpty = errors.New("topic filter cannot be empty")
-	errMQTTMalformedVarInt          = errors.New("malformed variable int")
-	errMQTTSecondConnectPacket      = errors.New("received a second CONNECT packet")
-	errMQTTServerNameMustBeSet      = errors.New("mqtt requires server name to be explicitly set")
-	errMQTTUserMixWithUsersNKeys    = errors.New("mqtt authentication username not compatible with presence of users/nkeys")
-	errMQTTTokenMixWIthUsersNKeys   = errors.New("mqtt authentication token not compatible with presence of users/nkeys")
-	errMQTTAckWaitMustBePositive    = errors.New("ack wait must be a positive value")
-	errMQTTStandaloneNeedsJetStream = errors.New("mqtt requires JetStream to be enabled if running in standalone mode")
-	errMQTTConnFlagReserved         = errors.New("connect flags reserved bit not set to 0")
-	errMQTTWillAndRetainFlag        = errors.New("if Will flag is set to 0, Will Retain flag must be 0 too")
-	errMQTTPasswordFlagAndNoUser    = errors.New("password flag set but username flag is not")
-	errMQTTCIDEmptyNeedsCleanFlag   = errors.New("when client ID is empty, clean session flag must be set to 1")
-	errMQTTEmptyWillTopic           = errors.New("empty Will topic not allowed")
-	errMQTTEmptyUsername            = errors.New("empty user name not allowed")
-	errMQTTTopicIsEmpty             = errors.New("topic cannot be empty")
-	errMQTTPacketIdentifierIsZero   = errors.New("packet identifier cannot be 0")
-	errMQTTUnsupportedCharacters    = errors.New("character ' ' not supported for MQTT topics")
-	errMQTTInvalidSession           = errors.New("invalid MQTT session")
+	errMQTTNotWebsocketPort           = errors.New("MQTT clients over websocket must connect to the Websocket port, not the MQTT port")
+	errMQTTTopicFilterCannotBeEmpty   = errors.New("topic filter cannot be empty")
+	errMQTTMalformedVarInt            = errors.New("malformed variable int")
+	errMQTTSecondConnectPacket        = errors.New("received a second CONNECT packet")
+	errMQTTServerNameMustBeSet        = errors.New("mqtt requires server name to be explicitly set")
+	errMQTTUserMixWithUsersNKeys      = errors.New("mqtt authentication username not compatible with presence of users/nkeys")
+	errMQTTTokenMixWIthUsersNKeys     = errors.New("mqtt authentication token not compatible with presence of users/nkeys")
+	errMQTTAckWaitMustBePositive      = errors.New("ack wait must be a positive value")
+	errMQTTJSAPITimeoutMustBePositive = errors.New("JS API timeout must be a positive value")
+	errMQTTStandaloneNeedsJetStream   = errors.New("mqtt requires JetStream to be enabled if running in standalone mode")
+	errMQTTConnFlagReserved           = errors.New("connect flags reserved bit not set to 0")
+	errMQTTWillAndRetainFlag          = errors.New("if Will flag is set to 0, Will Retain flag must be 0 too")
+	errMQTTPasswordFlagAndNoUser      = errors.New("password flag set but username flag is not")
+	errMQTTCIDEmptyNeedsCleanFlag     = errors.New("when client ID is empty, clean session flag must be set to 1")
+	errMQTTEmptyWillTopic             = errors.New("empty Will topic not allowed")
+	errMQTTEmptyUsername              = errors.New("empty user name not allowed")
+	errMQTTTopicIsEmpty               = errors.New("topic cannot be empty")
+	errMQTTPacketIdentifierIsZero     = errors.New("packet identifier cannot be 0")
+	errMQTTUnsupportedCharacters      = errors.New("character ' ' not supported for MQTT topics")
+	errMQTTInvalidSession             = errors.New("invalid MQTT session")
 )
 
 type srvMQTT struct {
@@ -281,6 +282,7 @@ type mqttJSA struct {
 	quitCh    chan struct{}
 	domain    string // Domain or possibly empty. This is added to session subject.
 	domainSet bool   // covers if domain was set, even to empty
+	timeout   time.Duration
 }
 
 type mqttJSPubMsg struct {
@@ -696,6 +698,9 @@ func validateMQTTOptions(o *Options) error {
 	if mo.AckWait < 0 {
 		return errMQTTAckWaitMustBePositive
 	}
+	if mo.JSAPITimeout < 0 {
+		return errMQTTJSAPITimeoutMustBePositive
+	}
 	// If strictly standalone and there is no JS enabled, then it won't work...
 	// For leafnodes, we could either have remote(s) and it would be ok, or no
 	// remote but accept from a remote side that has "hub" property set, which
@@ -1152,6 +1157,12 @@ func (s *Server) mqttCreateAccountSessionManager(acc *Account, quitCh chan struc
 	c.acc = acc
 
 	id := s.NodeName()
+
+	mqttJSAPITimeout := opts.MQTT.JSAPITimeout
+	if mqttJSAPITimeout == 0 {
+		mqttJSAPITimeout = mqttDefaultJSAPITimeout
+	}
+
 	replicas := opts.MQTT.StreamReplicas
 	if replicas <= 0 {
 		replicas = s.mqttDetermineReplicas()
@@ -1163,12 +1174,13 @@ func (s *Server) mqttCreateAccountSessionManager(acc *Account, quitCh chan struc
 		sessLocked: make(map[string]struct{}),
 		flappers:   make(map[string]int64),
 		jsa: mqttJSA{
-			id:     id,
-			c:      c,
-			rplyr:  mqttJSARepliesPrefix + id + ".",
-			sendq:  newIPQueue[*mqttJSPubMsg](s, qname+"send"),
-			nuid:   nuid.New(),
-			quitCh: quitCh,
+			id:      id,
+			c:       c,
+			rplyr:   mqttJSARepliesPrefix + id + ".",
+			sendq:   newIPQueue[*mqttJSPubMsg](s, qname+"send"),
+			nuid:    nuid.New(),
+			quitCh:  quitCh,
+			timeout: mqttJSAPITimeout,
 		},
 	}
 	if !testDisableRMSCache {
@@ -1546,7 +1558,7 @@ func (s *Server) mqttDetermineReplicas() int {
 //////////////////////////////////////////////////////////////////////////////
 
 func (jsa *mqttJSA) newRequest(kind, subject string, hdr int, msg []byte) (any, error) {
-	return jsa.newRequestEx(kind, subject, _EMPTY_, hdr, msg, mqttJSAPITimeout)
+	return jsa.newRequestEx(kind, subject, _EMPTY_, hdr, msg)
 }
 
 func (jsa *mqttJSA) prefixDomain(subject string) string {
@@ -1559,8 +1571,8 @@ func (jsa *mqttJSA) prefixDomain(subject string) string {
 	return subject
 }
 
-func (jsa *mqttJSA) newRequestEx(kind, subject, cidHash string, hdr int, msg []byte, timeout time.Duration) (any, error) {
-	responses, err := jsa.newRequestExMulti(kind, subject, cidHash, []int{hdr}, [][]byte{msg}, timeout)
+func (jsa *mqttJSA) newRequestEx(kind, subject, cidHash string, hdr int, msg []byte) (any, error) {
+	responses, err := jsa.newRequestExMulti(kind, subject, cidHash, []int{hdr}, [][]byte{msg})
 	if err != nil {
 		return nil, err
 	}
@@ -1578,7 +1590,7 @@ func (jsa *mqttJSA) newRequestEx(kind, subject, cidHash string, hdr int, msg []b
 //
 // Note that each response may represent an error and should be inspected as
 // such by the caller.
-func (jsa *mqttJSA) newRequestExMulti(kind, subject, cidHash string, hdrs []int, msgs [][]byte, timeout time.Duration) ([]*mqttJSAResponse, error) {
+func (jsa *mqttJSA) newRequestExMulti(kind, subject, cidHash string, hdrs []int, msgs [][]byte) ([]*mqttJSAResponse, error) {
 	if len(hdrs) != len(msgs) {
 		return nil, fmt.Errorf("unreachable: invalid number of messages (%d) or header offsets (%d)", len(msgs), len(hdrs))
 	}
@@ -1630,7 +1642,7 @@ func (jsa *mqttJSA) newRequestExMulti(kind, subject, cidHash string, hdrs []int,
 	c := 0
 	responses := make([]*mqttJSAResponse, len(msgs))
 	start := time.Now()
-	t := time.NewTimer(timeout)
+	t := time.NewTimer(jsa.timeout)
 	defer t.Stop()
 	for {
 		select {
@@ -1789,7 +1801,7 @@ func (jsa *mqttJSA) loadLastMsgForMulti(streamName string, subjects []string) ([
 		headerBytes = append(headerBytes, 0)
 	}
 
-	all, err := jsa.newRequestExMulti(mqttJSAMsgLoad, fmt.Sprintf(JSApiMsgGetT, streamName), _EMPTY_, headerBytes, marshaled, mqttJSAPITimeout)
+	all, err := jsa.newRequestExMulti(mqttJSAMsgLoad, fmt.Sprintf(JSApiMsgGetT, streamName), _EMPTY_, headerBytes, marshaled)
 	// all has the same order as subjects, preserve it as we unmarshal
 	responses := make([]*JSApiMsgGetResponse, len(all))
 	for i, v := range all {
@@ -1847,7 +1859,7 @@ func (jsa *mqttJSA) storeSessionMsg(domainTk, cidHash string, hdr int, msg []byt
 
 	// Passing cidHash will add it to the JS reply subject, so that we can use
 	// it in processSessionPersist.
-	smri, err := jsa.newRequestEx(mqttJSASessPersist, subject, cidHash, hdr, msg, mqttJSAPITimeout)
+	smri, err := jsa.newRequestEx(mqttJSASessPersist, subject, cidHash, hdr, msg)
 	if err != nil {
 		return nil, err
 	}
@@ -2982,7 +2994,7 @@ func (as *mqttAccountSessionManager) transferUniqueSessStreamsToMuxed(log *Serve
 	}()
 
 	jsa := &as.jsa
-	sni, err := jsa.newRequestEx(mqttJSAStreamNames, JSApiStreams, _EMPTY_, 0, nil, 5*time.Second)
+	sni, err := jsa.newRequestEx(mqttJSAStreamNames, JSApiStreams, _EMPTY_, 0, nil)
 	if err != nil {
 		log.Errorf("Unable to transfer MQTT session streams: %v", err)
 		return

server/mqtt_test.go

@@ -469,6 +469,11 @@ func TestMQTTValidateOptions(t *testing.T) {
 			o.MQTT.AckWait = -10 * time.Second
 			return o
 		}, errMQTTAckWaitMustBePositive},
+		{"js api timeout should be >=0", func() *Options {
+			o := mqtto.Clone()
+			o.MQTT.JSAPITimeout = -10 * time.Second
+			return o
+		}, errMQTTJSAPITimeoutMustBePositive},
 	} {
 		t.Run(test.name, func(t *testing.T) {
 			err := validateMQTTOptions(test.getOpts())
@@ -498,6 +503,7 @@ func TestMQTTParseOptions(t *testing.T) {
 		{"ack wait", `mqtt: {ack_wait: abc}`, nil, "invalid duration"},
 		{"max ack pending", `mqtt: {max_ack_pending: abc}`, nil, "not int64"},
 		{"max ack pending too high", `mqtt: {max_ack_pending: 12345678}`, nil, "invalid value"},
+		{"js_api_timeout bad duration", `mqtt: {js_api_timeout: abc}`, nil, "invalid duration"},
 		// Positive tests
 		{"tls gen fails", `
 			mqtt {
@@ -627,6 +633,17 @@ func TestMQTTParseOptions(t *testing.T) {
 				}
 				return nil
 			}, ""},
+		{"js_api_timeout",
+			`
+			mqtt {
+				js_api_timeout: "60s"
+			}
+			`, func(o *MQTTOpts) error {
+				if o.JSAPITimeout != 60*time.Second {
+					return fmt.Errorf("Invalid JS API timeout: %v", o.JSAPITimeout)
+				}
+				return nil
+			}, ""},
 	} {
 		t.Run(test.name, func(t *testing.T) {
 			conf := createConfFile(t, []byte(test.content))

server/opts.go

@@ -616,6 +616,9 @@ type MQTTOpts struct {
 	// PubRels).
 	AckWait time.Duration
 
+	// JSAPITimeout defines timeout for JetStream api calls (default is 5 seconds)
+	JSAPITimeout time.Duration
+
 	// MaxAckPending is the amount of QoS 1 and 2 messages (combined) the server
 	// can send to a subscription without receiving any PUBACK for those
 	// messages. The valid range is [0..65535].
@@ -5205,6 +5208,8 @@ func parseMQTT(v any, o *Options, errors *[]error, warnings *[]error) error {
 			o.MQTT.NoAuthUser = mv.(string)
 		case "ack_wait", "ackwait":
 			o.MQTT.AckWait = parseDuration("ack_wait", tk, mv, errors, warnings)
+		case "js_api_timeout", "api_timeout":
+			o.MQTT.JSAPITimeout = parseDuration("js_api_timeout", tk, mv, errors, warnings)
 		case "max_ack_pending", "max_pending", "max_inflight":
 			tmp := int(mv.(int64))
 			if tmp < 0 || tmp > 0xFFFF {