Emqx v4.4.5 Publishing: new exclusive subscriptions and mqtt 5.0 publishing attribute support

In recent days, ,EMQX Open source Edition v4.3.16、 Open source Edition v4.4.5 And enterprise v4.3.11、 Enterprise Edition v4.4.5 Four maintenance versions were officially released .

This release realizes the connection with stream database HStreamDB Integration of , Provide one-stop data access and real-time processing analysis . The exclusive subscription function and the dynamic rule engine when republishing messages are added QoS Support with reserved message settings , At the same time, it supports API Set in MQTT 5.0 Publishing properties of （PUBLISH Properties）, Help users cope with more scenarios . In addition, a number of known BUG.

Welcome to download ：https://www.emqx.com/zh/try?product=enterprise

New features of rule engine

Integrate HStreamDB, One stop data access 、 Storage and Analysis

Include version Enterprise Edition v4.3.11 Enterprise Edition v4.4.5

HStreamDB It is a streaming database for data storage and real-time processing of the Internet of things . It uses standard SQL ( And its flow expansion ） As the main interface language , With real-time as the main feature , Set real-time data acquisition and capture system 、 Real time data storage system 、 Stream computing engine 、 Downstream data and application system are integrated , It aims to simplify the operation and maintenance management of data stream and the development of real-time applications .

The rules engine now supports EMQX Persistent data to HStreamDB, So as to realize the real-time processing, analysis and insight of these data . In the performance test ,EMQX stay 32 nucleus 64GB It can stably support 8 Wan Lian 、 Per second 8 ten thousand QoS 0、Payload 4KB Messages of persist to HStreamDB, Please refer to file .

Message republishing action supports message retention and dynamic QoS

Include version Open source Edition v4.3.16 Open source Edition v4.4.5 Enterprise Edition v4.3.11 Enterprise Edition v4.4.5

We introduce retained messages and dynamic... Into the message republishing function QoS Support , To meet the needs of users in specific scenarios . Among them, the demand for retaining messages comes from EMQX Question answering community , The purpose is to store the latest status of the client in EMQX For subsequent processing .

New exclusive subscription function

Include version Open source Edition v4.3.16 Open source Edition v4.4.5 Enterprise Edition v4.3.11 Enterprise Edition v4.4.5

Exclusive subscription only allows a single subscriber to subscribe to a topic , When using exclusive subscription , Can be easily implemented 「 Some data can only be processed by one subscriber at the same time 」 This kind of business .

The use of exclusive subscriptions is very similar to shared subscriptions , Use a specific topic prefix $exclusive Indicates that this is an exclusive subscription , After a client successfully subscribes , New clients will not be able to subscribe to the same topic again .

Exclusive subscription is off by default , It needs to be enabled in this configuration item ：

mqtt.exclusive_subscription = true

Examples of exclusive subscription effectiveness ：

//  success 
clientA.subscribe('$exclusive/t/1')

//  Failure , This topic has subscribers 
clientB.subscribe('$exclusive/t/1')

//  success , Ordinary topics without prefixes can still be successfully subscribed 
clientC.subscribe('t/1')

//  You need to bring a prefix to unsubscribe 
clientA.unsubscribe('$exclusive/t/1')
//  success 
clientB.subscribe('$exclusive/t/1')

News release API Support settings MQTT 5.0 Publishing properties （PUBLISH Properties）

Include version Open source Edition v4.4.5 Enterprise Edition v4.4.5

MQTT 5.0 It supports setting additional properties when publishing messages, such as Message expiration interval 、 topic alias and User properties etc. , In the new version, users can publish messages API Use this feature in , To meet more business needs .

The following is an example of message publishing with publishing properties ：

curl -i --basic -u admin:public -X POST "http://localhost:8081/api/v4/mqtt/publish" -d \
'{
  "topic":"t/1",
  "payload":"Hello World",
  "qos":1,
  "retain":false,
  "clientid":"emqx_c",
  "properties": {
    "user_properties": { "id": 10010, "name": "emqx", "foo": "bar"},
    "content_type": "text/plain",
    "message_expiry_interval": 3600
  }
}'

More functional optimizations

• Supported by CLI One click Update cluster License
• Dashboard And management API Of HTTPS Listeners can use password protected private key files , Provides key_password Configuration item
• Support the use of placeholders in topic rewrite rules %u and %c
• Optimize rule engine resource creation UI, For example, the options that are not commonly used in the folding part
• by ExHook At the bottom gRPC The connection is open KeepAlive、TCP_NODELAY、SO_RCVBUF and SO_SNDBUF common 4 One and TCP Related configuration items

BUG Repair

Various versions BUG For repair details, please check ：

• Open source Edition v4.3.16： https://www.emqx.com/zh/changelogs/broker/4.3.16
• Open source Edition v4.4.5： https://www.emqx.com/zh/changelogs/broker/4.4.5
• Enterprise Edition v4.3.11：https://www.emqx.com/zh/changelogs/enterprise/4.3.11
• Enterprise Edition v4.4.5： https://www.emqx.com/zh/changelogs/enterprise/4.4.5