All Questions
Tagged with publish-subscribe mqtt
146 questions
0
votes
0
answers
36
views
ESP32: Crash during check if PubSubClient is still connected - but why?
I recently noticed some seemingly random crashs on my esp32 application.
I was able to catch a crash message which is the following and which is due to some erroneuos behaviour when I check if my ...
- 21
0
votes
1
answer
319
views
How to publish and subscribe from and to device in iot hub?
Currently I'm trying to send a temperature data to my azure iot hub using publish (python) and at the same time I'm trying to read or receive the temperature data using subscribe method in another ...
- 41
0
votes
0
answers
346
views
unable to connect to thingspeak/mqtt/esp32
#include <PubSubClient.h>
#include <WiFi.h>
const char* ssid = "Singh";
const char* password = "12345678";
const char* mqtt_server = "mqtt3.thingspeak.com";
...
-1
votes
1
answer
145
views
MQTT connection passed as a property doen't work for Subscribe and disconnect
I am using MQTT messages as a prerequisite . Hence its sufficient to make one connection which is shared between thread groups.
I tried to save connection as a property and it works absolutely fine ...
- 1
0
votes
0
answers
485
views
MQTT Databaricks,Azure
I am having issues being able to subscribe to payloads from a instance of databricks running. I have configured a vpn within my dev environment and have my cluster from databricks and virtual machine ...
0
votes
1
answer
635
views
How to subscribe to multiple mqtt topics in android hive MQ client
i can't seem to find a way to subscribe to more than just one topic using the .topicfilter("topic/test) . anybody got an idea how to make it subscribe to list of topics ?
- 748
0
votes
1
answer
456
views
How can I subscribe to my AWS IoT Topic in Angular?
I searched for hours and hours and tried everything but it just won't work. I have an ESP32 which send/receives IoT messages on a specific topic. This is my current code to publish:
region = "eu-...
0
votes
1
answer
89
views
Can I use any MQTT library to connect to an existing device with its own broker?
I'm new to MQTT. I recently built a small simulation system, where I use Solace Pub/Sub Broker, and use Solace client library to build the message producer and consumer.
So now if I am provided a real ...
1
vote
1
answer
807
views
Mosquitto MQTT Client return error 10 in loop_start function call after connect call
I'm writing an MQTT client which simply connects to the broker, and publishes or subscribes to a topic.
Here in the program, I try to Connect to Broker and then call the loop_forever() function and is ...
1
vote
1
answer
411
views
how to send TWO strings with arduino pubsubclient library - getting invalid operand error
probably a simple enough thing - so much so I thought it would be worth asking.
I'm familiar with the pubsub mqtt client library from the hirotasker port for Spark/Particle devices. I am trying to use ...
- 153
0
votes
1
answer
245
views
MQTT Subscriber Failed to Subscribe to the Same Topic With MQTT Publisher
I'm trying to make a simple "transit schedule changes" program using python MQTT where the publisher can input flight number (will be used as topic) and new flight time, while the transit ...
- 1
0
votes
1
answer
1k
views
Can we publish to multiple topics at the same time using mosquitto_pub client?
When I try to publish to different topics using same client id it disconnects the previous connection.
It says the mosquitto_pub publishes a single message at a time so was wondering if this is a ...
0
votes
0
answers
479
views
MQTT Connectivity issue - Message Expiry Interval
I have been encountering an issue for a long time but I haven't found any solution yet, despite reading the protocol version 5 standard and the emqx documentation.
I want to publish messages with a ...
- 21
0
votes
1
answer
578
views
Batch processing in mqtt
Is it possible to use batch processing in mqtt protocol.
Instead of reading and processing message by message, can we process a group of messages together in mqtt?
- 21
1
vote
0
answers
215
views
RabbitMq-mqtt-plugin publishing messages in batches
I am using rabbitmq-mqtt plugin to publish 1 million messages, but it is taking too many hours to publish messages. So, I want to publish messages in batches or to use batch confirm. I am using ...
- 21