I see some weird behaviour with the mqtt-in node. When I change the output to "a parsed JSON object" > deploy. inject something in mqtt-out node, i get a single response. Change the output to "auto-detect" > deploy. inject something again, the messages are repeated. Change it again to json, deplo…

This is really strange behaviour and it makes mqtt unusable for me. Only the initial setup works, touch it and I am stuck with repeated messages until I remove the nodes, deploy and add them again. @knolleary do I do something wrong or did I find a bug ?

Has the message been published with the retained flag set, meaning youll receive it each time the node subscribes?

No retain flag, I have cleared everything on the broker. Looking at the subscription, only 1 message exists on the broker, gets repeated in node-red. Test flow: [{"id":"380b9424.fcc454","type":"mqtt in","z":"c0f7a95e.a66d08","name":"","topic":"test/testtopic","qos":"2","datatype":"auto","broker":…

I could swear that there was a thread in the not too long past that talked about a MQTT broker monitoring tool. But do you think I can find it...nooooo....drat's I thought I had it bookmarked. Anyway If you can find it, it might shed some light on what the broker is doing. In addition thei shread …

[image] bakman2: I can reproduce it. Is this just me ? I experienced the same thing. Restarting Node Red helped also. The broker wasn't the source of evil.

Restarting works temporarily unfortunately

Hi @bakman2 I can't reproduce this with the flow you've provided. I always get the expected one message. What broker are you using?

I have also seen multiple MQTT messages. In the end I just used an RBE node to handle it. Should have reported it but suspected it was something I done wrong or an MQTT thing at the time. Fwiw, I was using the most excellent EMQX broker and node-red v0.20 beta something at the time.

Node-RED

Node-RED Forum

Mqtt-in repeated messages bug?

General

bakman2 28 March 2019 20:56 10

I am using eclipse mosquitto.

It starts repeating once I change something to the mqtt nodes.

Topic		Replies	Views
MQTT node - messages received twice!? General mqtt	23	1045	17 November 2022
Repeated messages with Vernemq mqtt broker General	14	1852	18 May 2020
MQTT not reconnecting if only only one mqtt node using it General	6	442	21 October 2022
MQTT In: Disconnect after Re-Deploy General mqtt	4	609	1 December 2022
MQTT Message Not Being Sent General mqtt	25	434	2 September 2024

Copyright OpenJS Foundation and Node-RED contributors. All rights reserved. The OpenJS Foundation has registered trademarks and uses trademarks. For a list of trademarks of the OpenJS Foundation, please see our Trademark Policy and Trademark List. Trademarks and logos not indicated on the list of OpenJS Foundation trademarks are trademarks™ or registered® trademarks of their respective holders. Use of them does not imply any affiliation with or endorsement by them.

Mqtt-in repeated messages bug?

Related topics