mqtt

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 由 翻译 强力驱动 问题: MQTTnet is a high performance .NET library for MQTT based communication. This is GitHub Link. https://github.com/chkr1011/MQTTnet . It provides a MQTT client and a MQTT server (broker). The implementation is based on the documentation from http://mqtt.org/ . This is how I have created managed MQTT client. Here is the link https://github.com/chkr1011/MQTTnet/wiki/ManagedClient // Setup and start a managed MQTT client. var options = new ManagedMqttClientOptionsBuilder () . WithAutoReconnectDelay ( TimeSpan . FromSeconds ( 5 )) .

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: Does anyone know of an MQTT broker that runs on an Android smartphone? I tried to Google and found nothing, and on the app store there seems to be only one app with just 10 downloads, so I'm not sure how well it works. 回答1: Add these dependencies to the gradle dependencies{ compile 'io.moquette:moquette-netty-parser:0.8.1' compile 'io.moquette:moquette-broker:0.8.1' compile 'io.moquette:moquette-parser-commons:0.8.1' } And use io.moquette.server.Server server = new io.moquette.server.Server(); server.startServer(); to start broker server.

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: I closely paralleled the approach taken in how-to-use-moment-js-library-in-angular-2-typescript-app but still get error TS2307: Cannot find module 'mqtt'. npm install --save mqtt <s>typings install --save mqtt</s that didn't find the typings but this did... typings install mqtt --save --ambient my tsconfig.conf looks like this { "compilerOptions": { "noImplicitAny": true, "module": "commonjs", "target": "ES5", "emitDecoratorMetadata": true, "experimentalDecorators": true, "sourceMap": true, "declaration": true }, "files": [ "ng2-mqtt.ts" ],

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: I am new to Android and services. My aim is to be able to set-up subscriptions and do publications on topic strings. The topic strings and client ID are set-up after parsing input of text fields. I am using the Paho MQTT service (downloaded the source and built the JAR). The following causes a Null Pointer Exception at c.publish() . The logcat shows the exception at the IMqttDeliveryToken publish(String topic, MqttMessage message, Object userContext, IMqttActionListener callback) method in MqttAndroidClient where a delivery token is being

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: I built a python script that sends MQTT message periodically. This is the JSON string sent to the backend: {"Id": "1234", "Ut": 1488395951, "Temp": 22.86, "Rh": 48.24} On backend side, I want to store the MQTT message into DynamoDB table. I followed an Amazon tutorial and the data contained into the MQTT messages are stored into the table. My problem regards the table columns. The table has only 3 colums: Id: Partition Key Ut: Sort Key Payload: contains the mqtt message. It is possible to have columns for each key contained into MQTT message

1.由于emqttd是用Erlang语言编写的，所以，在Linux下安装时，需要先安装Erlang。 sudo yum -y install make gcc gcc -c++ kernel-devel m4 ncurses-devel openssl-devel wget http: // www.erlang.org/download/otp_src_R13B04.tar.gz tar xfvz otp_src_R13B04. tar .gz cd otp_src_R13B04 / 编译此时会出大问题，会提示没有java什么的，需要进行下面操作， 好吧，想办法安装下unixODBC: 安装 ODBC 下载unixODBC源码包( http://www.unixodbc.org/unixODBC-2.2.1.tar.gz )放到某处比如/usr/local下，然后运行下述命令： tar zxvf unixODBC- 2.2 . 1 . tar .gz 　　cd unixODBC - 2.2 . 1 　　. /configure --prefix=/usr/local/unixODBC- 2.2 . 1 --includedir=/usr/include --libdir=/usr/lib -bindir=/usr/bin --sysconfdir=/etc --enable

什么是MQTT 　　　　MQTT（Message Queuing Telemetry Transport，消息队列遥测传输）是IBM开发的一个即时通讯协议，有可能成为物联网的重要组成部分。该协议支持所有平台，几乎可以把所有联网物品和外部连接起来，是一种基于发布/订阅（publish/subscribe）模式的“轻量级”通讯协议，该协议构建于TCP/IP协议上，被用来当做传感器和制动器（比如通过Twitter让房屋联网）的通信协议。 MQTT特点 　　　　MQTT协议是为大量计算能力有限，且工作在低带宽、不可靠的网络的远程传感器和控制设备通讯而设计的协议，它具有以下主要的几项特性： 　　　　1、使用发布/订阅消息模式，提供一对多的消息发布，解除应用程序耦合； 　　　　2、对负载内容屏蔽的消息传输； 　　　　3、使用 TCP/IP 提供网络连接； 　　　　4、有三种消息发布服务质量： “至多一次”，消息发布完全依赖底层 TCP/IP 网络。会发生消息丢失或重复。这一级别可用于如下情况，环境传感器数据，丢失一次读记录无所谓，因为不久后还会有第二次发送。 “至少一次”，确保消息到达，但消息重复可能会发生。 “只有一次”，确保消息到达一次。这一级别可用于如下情况，在计费系统中，消息重复或丢失会导致不正确的结果。 　　　　5、小型传输，开销很小（固定长度的头部是 2 字节），协议交换最小化

import mqtt from 'mqtt' import MQTTConnect from '../../assets/js/MQTTConnect' reset () { this . subscriptions = [] this . receivedMessages = [] this . subTopic = '/xxx/' + this . xwNum } , loadConnect () { console . log (MQTTConnect. options ) if (MQTTConnect. client && MQTTConnect. client . connected ) { this . client = MQTTConnect. client Object. keys (MQTTConnect. options ). forEach (( item ) => { this [ item ] = MQTTConnect. options [ item ] }) } } , stashConnect () { MQTTConnect. client = this . client console . log (MQTTConnect. options ) Object. keys (MQTTConnect. options ). forEach ((

环境：redhat 6 在root前提下，在 /etc/yum.repos.d/下新建mosquitto.repo文件 gedit /etc/yum.repos.d/mosquitto.repo 然后，从官网上找到RHEL6的文件内容： [home_oojah_mqtt] name=mqtt (RedHat_RHEL-6) type=rpm-md baseurl=http://download.opensuse.org/repositories/home:/oojah:/mqtt/RedHat_RHEL-6/ gpgcheck=1 gpgkey=http://download.opensuse.org/repositories/home:/oojah:/mqtt/RedHat_RHEL-6/repodata/repomd.xml.key enabled=1 写入mosquitto.repo中。 之后就可以yum了， yum install mosquitto mosquitto-clients 接着一路选y。 安装完毕。 文章来源: Mosquitto在redhat中的安装

MQTT mosquitto EMQ2.2 1. 1.EMQ2.2 Erlang otp R19 EMQ2.2 emqttd-windows7-v2.2-beta.3.zip，python3.6，MQTTpaho.mqtt.python-master 因为公司的文档不能贴出来，就贴个别人的EMQ2.2的安装教程： https://blog.csdn.net/wangshuminjava/article/details/80589899 2.Mosquitto mosquitto python3 python3-pip paho-mqtt mosquitto安装： 目前最新的版本是1.4.14版本，将下载的 mosquitto-1.4.14.tar.gz 包解压； 进入 mosquitto-1.4.14 目录下； 执行 make 命令； 执行 make install 命令，直到安装完成； 需要注意的是paho库的安装，需要pip,这个教程很多。 2.测试方案 1. 3 台 2. 1 -2 1 2 1 N 3.测试 #fdisk -l; tcp Raid 4.监控负载情况 broker Tcp 状态 抓 established time_wait CPU I/O TCP 状态 cpu TCP 5.监控方式 Excel word 脚本的实现我写在另一篇博客中了： https:/