mqtt

问题 I have a laptop with a NodeJS client that should connect to an MQTT broker on an Ubuntu PC. The broker is running with TCP port 1883 and websocket port 9883. But when I run the client, it does not see the broker - only if I run the client program on the same PC the broker is on, it connects. This used to work before. I changed a few things about the network interfaces but reverted everything - so I have no idea what might be causing this. I added an alias for one of the eth interfaces, but

问题 For legacy reasons, I need to disable retained messages on an MQTT node running RabbitMQ. After researching the issue, it appears that the Rabbit MQ team has indeed added such a feature in a file called rabbit_mqtt_retained_msg_store_noop.erl. I am otherwise unfamiliar with the codebase and could not find mention of the noop retainer anywhere in the documentation. How do I enable rabbit_mqtt_retained_msg_store_noop ? 回答1: rabbit_mqtt_retained_msg_store_noop is enabled by adding thefollowing

问题 I'm working with HiveMQ Client and I wanted to know if there was a way to get the quality of service (QoS) that a client is subscribing with (in terms of a specific topic or in general)? I would be looking for a method I could invoke on a client like so: Mqtt5BlockingClient subscriber = Mqtt5Client.builder() .identifier(UUID.randomUUID().toString()) // the unique identifier of the MQTT client .serverHost("localhost") .serverPort(1883) .buildBlocking(); subscriber.getQoS("topic") // returns

问题 I'm learning about MQTT (specifically the paho C library) by reading and experimenting with variations on the async pub/sub examples. What's the difference between the MQTTAsync_deliveryComplete callback that you set with MQTTAsync_setCallbacks() vs. the MQTTAsync_onSuccess or MQTTAsync_onSuccess5 callbacks that you set in the MQTTAsync_responseOptions struct that you pass to MQTTAsync_sendMessage() ? All seem to deal with "successful delivery" of published messages, but from reading the

问题 I have been trying to implement an MQTT service using wmqtt.jar. Like most folks I started with looking at other peoples examples. I found several references to Dale Lane's post http://dalelane.co.uk/blog/?p=1599 and downloaded a version of his service from http://mosquitto.org/2011/11/android-mqtt-example-project/. My problem is that every example I try to run that uses wmqtt.jar in my emulator the code crashes as soon as any class that references MqttSimpleCallback with ajava.lang

问题 I'm using esp8266 with the firmware produced with Marcel's NodeMCU custom builds http://frightanic.com/nodemcu-custom-build/ I tested the "dev" branch and the "master". I changed a little bit the " Connect to MQTT Broker " code found here https://github.com/nodemcu/nodemcu-firmware -- init mqtt client with keepalive timer 120sec m = mqtt.Client("clientid", 120, "user", "password") m:on("connect", function(con) print ("connected") end) m:on("offline", function(con) print ("offline") end) -- m

问题 I have a problem with the following Lua code on an ESP8266... function sendData(humidity,temperature) -- Setup MQTT client and events print("sendData() entered") print("Setting up mqtt.Client...") m = mqtt.Client(mqtt_client_id, 120, username, password) print("Attempting client connect...") m:connect(mqtt_broker_ip , mqtt_broker_port, 0, function(conn) print("Connected to MQTT") print(" IP: " .. mqtt_broker_ip) print(" Port: " .. mqtt_broker_port) print(" Client ID: " .. mqtt_client_id) print

问题 Recently Microsoft Azure has added a MQTT backend to its' services. This service uses TLS do encrypt its traffic. I can't connect between Mosquitto and the Microsoft Azure Cloud. I downloaded the server certificate with echo -n | openssl s_client -connect mytarget.azure-devices.net:8883 | sed -ne '/-BEGIN CERTIFICATE-/,/-END CERTIFICATE-/p' > /tmp/test.cert And then tried to connect with mosquitto_sub mosquitto_sub -h mytarget.azure-devices.net -p 8883 -d -t devices/Device1/messages/events -i

问题 I have a question about spring. I make a connection with MQTT broker using Spring-Paho MqttPahoMessageDrivenChannelAdapter . Here is a java config part: @Bean @Description("mqtt inbound adapter: receives mqtt messages") public MessageProducer mqttInboundAdapter() { log.info("creating mqtt inbound adapter"); MqttPahoMessageDrivenChannelAdapter adapter = new MqttPahoMessageDrivenChannelAdapter( env.getProperty("mqtt.hostname")+":" +env.getProperty("mqtt.port"), "myClient", "#"); adapter

问题 It seems MQTTUtils Only provide three methods, def createStream(jssc: JavaStreamingContext, brokerUrl: String, topic: String, storageLevel: StorageLevel): JavaDStream[String] Create an input stream that receives messages pushed by a MQTT publisher. def createStream(jssc: JavaStreamingContext, brokerUrl: String, topic: String): JavaDStream[String] Create an input stream that receives messages pushed by a MQTT publisher. def createStream(ssc: StreamingContext, brokerUrl: String, topic: String,