CN108768826B - Message routing method based on MQTT and Kafka high concurrency scene - Google Patents
Message routing method based on MQTT and Kafka high concurrency scene Download PDFInfo
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- CN108768826B CN108768826B CN201810465578.2A CN201810465578A CN108768826B CN 108768826 B CN108768826 B CN 108768826B CN 201810465578 A CN201810465578 A CN 201810465578A CN 108768826 B CN108768826 B CN 108768826B
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- H—ELECTRICITY
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- H04L51/00—User-to-user messaging in packet-switching networks, transmitted according to store-and-forward or real-time protocols, e.g. e-mail
- H04L51/04—Real-time or near real-time messaging, e.g. instant messaging [IM]
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- H—ELECTRICITY
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- H04L47/125—Avoiding congestion; Recovering from congestion by balancing the load, e.g. traffic engineering
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- H—ELECTRICITY
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Abstract
The invention discloses a message routing method based on MQTT and Kafka high concurrency scenes, which fully utilizes the characteristic that an MQTT lightweight protocol supports simultaneous connection of millions of devices in communication, introduces a Kafka cluster to make up the defect that the MQTT protocol does not support load balancing, and meets the application requirements under the high concurrency scenes by virtue of the characteristic that the sequential writing speed of a disk is high, thereby greatly improving the message transmission speed and supporting the storage and asynchronous processing of real-time data streams.
Description
Technical Field
The invention relates to the field of data communication, in particular to a message routing method based on MQTT and Kafka high concurrency scenes.
Background
With the rapid development of internet technology, the popularization of intelligent terminal devices and the diversification of service requirements, the importance of data communication between terminal devices is increasingly highlighted, and especially in an application scenario in which data is collected by various devices and then is uniformly processed by computing devices, how to ensure the real-time performance of data acquisition in practical application and the availability in a high-concurrency scenario is ensured, and offline message storage in an unstable network environment becomes a key for solving the problem of data communication.
The MQTT protocol is an instant messaging protocol based on a 'publish/subscribe' mode, and can effectively realize one-to-many or many-to-many communication. The network service system is designed on the TCP protocol, has the characteristics of light weight, simplicity and easiness in implementation, and aims to provide reliable network service for terminal equipment in low-bandwidth and unstable network environments. It has very little communication overhead since its message header can be as short as 2 bytes. And it is optimized specifically for low power consumption objectives at the beginning of the design. More particularly, in order to meet different scene requirements, the MQTT supports three different qualities of service. And the system is provided with a testimony message and session storage function so as to solve the problem that the client is reconnected after being disconnected with the server under an unstable network environment.
Kafka is a distributed message system supporting partition storage and multiple copies, and can effectively solve the problem of data processing after agent downtime by adopting a publish/subscribe message processing mode. Kafka operates in a cluster, and is formed by multiple brokers together. The producer sends the message to a specific topic, which is then consumed by the consumers subscribing to the topic in poll. Each topic is divided into one or more partitions, each partition is composed of a series of ordered and immutable messages and is an ordered queue. In particular, Kafka writes to a disk in a sequential write manner, and thus at a much faster rate than writes to a disk randomly. In addition, Kafka introduces the concept of consuming groups, each consumer belongs to a specific consuming group, a message under the same partition can be consumed by only one consumer in the same consuming group, but a plurality of consuming groups can consume the message at the same time.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide a message routing method based on MQTT and Kafka high concurrency scenes, which makes full use of the characteristic that an MQTT lightweight protocol supports simultaneous connection of millions of devices in communication, introduces Kafka clusters to make up the defect that the MQTT protocol does not support load balancing, and meets the application requirements in the high concurrency scenes by virtue of the characteristic that the sequential writing speed of a disk is high, thereby greatly improving the message transmission speed and supporting the storage and asynchronous processing of real-time data streams.
The purpose of the invention is realized by the following technical scheme:
the message routing method based on the MQTT and Kafka high concurrency scene comprises the following steps:
receiving user messages in a high concurrency scene by using a partition mechanism of Kafka, writing the user messages into a disk in a sequential writing mode, storing the user messages based on a message queue of a release/subscription mode, and realizing load balancing by using a Kafka proxy cluster;
then, retrieving and filtering the messages through Kafka Stream, storing the messages into a database in a persistent mode, and keeping monitoring the state of a receiving end; sending the filtered data to an MQTT server and storing the data under different topics;
and finally, matching by using receiving terminals which subscribe different topics in the MQTT protocol to acquire messages, and sending a status message by the receiving terminals to update an online list every time the receiving terminals get online or get offline.
The method comprises the steps that a user message under a high concurrency scene is received by utilizing a partition mechanism of Kafka, the message is stored and cached in a mode of disk sequential writing, and a certain time limit is provided; since there are one or more partitions under each Topic in Kafka, when a user sends a message to a client, the user can specify the partition to which the message is to be sent, set partition. Because creating a theme in Kafka is an operation that affects performance, a corresponding theme is not created for each session request initiated by a user in Kafka proxy, and a method of multiple partitions under one theme is adopted, backup is completed based on multiple brokers to save the partitions, and load balancing is achieved.
And the user message records are sent in a Key-Value Key Value pair mode, and the sender ID and the receiver ID are issued together as a Key. This enables Kafka to handle high concurrent data volumes and undertake the task of message storage.
The method comprises the following steps of retrieving, filtering and storing the messages into a database in a persistent mode through the Kafka Stream, and keeping monitoring on the state of a receiving end, wherein the method specifically comprises the following steps:
establishing a Stream processing topology for the message records stored in each partition through Kafka Stream, and performing processing in a mode of deserializing key values into data objects;
the flow processing topology comprises a Source processing node, a Sink processing node and M user-defined processing nodes, and message records can be screened and filtered by using aggregation operation; wherein M is more than or equal to 2;
the filtered data are serialized and then sent to a consumption end which subscribes corresponding Topic, in the consumption end, messages are recorded in a persistent database through multithreading, and a result after persistence is processed through a callback function;
in addition, the consuming end also needs to subscribe another topic for monitoring the online state of the receiving end and maintains an online list.
The filtered data is sent to an MQTT server and stored under different topics, specifically:
at a consumption end of Kafka, consuming messages stored in a Kafka Broker partition in advance one by one, and extracting a Key of each message, wherein the Key comprises a sender ID and a receiver ID of the message;
when the release Message specifies Topic, the ID of the receiver is required to be used as the parent Topic of the ID of the sender, and the ID of the sender is added in front of the Message Body so as to be convenient for the analysis of the receiving end;
the receiver subscribes to the Topic with the self ID as the first level after starting, and receives all messages with the self ID as the first level by using a wildcard; after parsing the Message Body of the received Message, the sending source of the Message content is identified.
Since MQTT supports multilevel Topic and wildcards can be used to match the multi-level topics, the key in designing the message routing system is how to make the receiver identify the specific sender.
The receiving end sends a status message to update the online list every time the receiving end goes online or offline, specifically:
when the receiver is started, the service quality needs to be set and whether the Session is cleared or not is needed to be set; because the receiving end needs to obtain the off-line message, Session needs to be saved, and the service quality is set as At Least one, so that the confirmation of the message is reduced, and the concurrency capability of Kafka is improved;
in addition, a will advice message is set, and when a receiver is offline, the offline message is sent to Kafka, so that the phenomenon that the message cannot be consumed in the MQTT server all the time and the memory space is occupied is avoided; when brought back online, a message is again sent to Kafka to update its maintained list of online receivers.
Compared with the prior art, the invention has the following advantages and beneficial effects:
the invention sets up a message routing system model based on MQTT and Kafka based on the premise of solving the problem that long-time response delay is caused by transmitting data to a server by a large number of terminal devices in a high-concurrency scene, even the server is down, realizes load balancing according to a self-defined partition strategy, and completes communication through a lightweight protocol of MQTT. It is suitable for small and medium scale communication system and can meet the application requirement of one-to-many or many-to-many. And supports well real-time and asynchronous data processing. And the method also has good expandability and can be further combined with solutions such as multilayer cache, distributed architecture and the like to process larger-scale concurrent data volume.
Drawings
Fig. 1 is a schematic structural diagram of a message routing system based on MQTT and Kafka high concurrency scenarios according to the present invention.
Fig. 2 is a message transmission sequence chart of the message routing method based on MQTT and Kafka high concurrency scenario according to the present invention.
Detailed Description
The present invention will be described in further detail with reference to examples and drawings, but the present invention is not limited thereto.
As shown in fig. 1, the message routing system based on the MQTT and Kafka high concurrency scenario is used for implementing a message routing method based on the MQTT and Kafka high concurrency scenario, and includes a sending end, a Kafka Broker, a Kafka provider, a MongoDB, an MQTT Broker, and a receiving end.
As shown in fig. 2, the message routing method in the high concurrency scenario based on MQTT and Kafka includes the following steps:
starting a Kafka cluster and an MQTT server, operating a sending end instance SenderId, periodically sending data collected at the sending end to a Kafka agent, setting the main topic of message sending as ' Msg-Record ', setting Key of the message as ' ReceiverId/SenderId ', adding the SenderId ' in front of the content of a message body, setting a partition strategy of the data as polling, namely, sequentially writing the data into each partition, and setting the time granularity as two days;
running a KStream program, designating Topic as 'Msg-Record' at a source processing node, deserializing data in a partition, then entering a stream processing topology, filtering invalid data through a filter in a self-defined stream processing node class, and retransmitting a message Record to a Kafka consumer at a Sink processing node;
the method comprises the steps that a consumer operating the Kafka periodically pulls messages in a poll mode, a Key in each message record is extracted and serves as a Topic issued by MQTT communication, in addition, the Kafka consumer subscribes to a Monitor-Receiver Topic, a list of all online receiving ends is maintained, an MQTT client side instance is operated, if the list of the online receiving ends currently has a receiverId, data records are issued to an MQTT server, and otherwise, the data records are stored in a disk to reduce communication traffic and avoid memory occupation. In addition, a thread is additionally opened through an execution class, and the message is stored in a database MongoDB for persistence. Setting a callback function for asynchronously processing a result of whether persistence is successful or not;
starting a receiving end instance ReceiverId, and carrying out a series of related parameter configurations, which comprises the following steps: saving the conversation record to obtain the unreceived message in an offline state; setting the service quality to be at least once so as to reduce unnecessary message confirmation delay and enhance concurrency; and subscribing the 'ReceiverId/#' theme, matching and receiving all the messages sent to the receiving end, analyzing the content of the received message body, and distinguishing that the message source is from the 'SenderId'. Setting a testimony message, releasing the content of the message body which is 'ReceiverId offline' once the receiving end is offline to 'Monitor-Receiver', analyzing the Kafka consumer subscribed to the topic after receiving the testimony message, removing 'ReceiverId' from the current online receiving end list, blocking all messages which take 'ReceiverId' as the first-level subject, and reducing unnecessary communication traffic and memory occupation. Once the Receiver comes online again, it sends the online information to the "Monitor-Receiver" topic again, and its corresponding instance Id is added to the list of online receiving end. The specific flow of message delivery is shown in fig. 2.
The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents thereof, and all such changes, modifications, substitutions, combinations, and simplifications are intended to be included in the scope of the present invention.
Claims (4)
1. The message routing method based on the MQTT and Kafka high concurrency scene is characterized by comprising the following steps of:
receiving user messages in a high concurrency scene by using a partition mechanism of Kafka, writing the user messages into a disk in a sequential writing mode, storing the user messages based on a message queue of a release/subscription mode, and realizing load balancing by using a Kafka proxy cluster;
then, retrieving and filtering the messages through Kafka Stream, storing the messages into a database in a persistent mode, and keeping monitoring the state of a receiving end; sending the filtered data to an MQTT server and storing the data under different topics;
the method comprises the following steps of retrieving, filtering and storing the messages into a database in a persistent mode through the Kafka Stream, and keeping monitoring on the state of a receiving end, wherein the method specifically comprises the following steps:
establishing a Stream processing topology for the message records stored in each partition through Kafka Stream, and performing processing in a mode of deserializing key values into data objects;
the flow processing topology comprises a Source processing node, a Sink processing node and M user-defined processing nodes, and message records can be screened and filtered by using aggregation operation; wherein M is more than or equal to 2;
the filtered data are serialized and then sent to a consumption end which subscribes corresponding Topic, in the consumption end, messages are recorded in a persistent database through multithreading, and a result after persistence is processed through a callback function;
in addition, the consumption end also needs to subscribe another theme for monitoring the online state of the receiving end and maintains an online list;
finally, matching is carried out by the receiving ends which subscribe different topics in the MQTT protocol to obtain messages, and the receiving ends send state messages to update an online list every time the receiving ends get online or get offline;
the receiving end sends a status message to update the online list every time the receiving end goes online or offline, specifically:
when the receiver is started, the service quality needs to be set and whether the Session is cleared or not is needed to be set; because the receiving end needs to obtain the off-line message, Session needs to be saved, and the service quality is set as At Least one cause Once;
in addition, a will advice message is set, and when a receiver is offline, the offline message is sent to Kafka, so that the phenomenon that the message cannot be consumed in the MQTT server all the time and the memory space is occupied is avoided; when brought back online, a message is again sent to Kafka to update its maintained list of online receivers.
2. The message routing method based on MQTT and Kafka high concurrency scene of claim 1, wherein the partition mechanism utilizing Kafka is used for receiving the user message in the high concurrency scene, and the message routing method is used for storing and caching the message in a mode of depending on sequential writing of a disk and has a certain time limit; when a user sends a message at a client, the user specifies a partition to which the message is to be sent, sets partition.
3. The message routing method based on the MQTT and Kafka high concurrency scenario of claim 2, wherein the record of the user message is sent in a Key-Value pair manner, and the sender ID and the receiver ID are issued together as a Key.
4. The message routing method based on MQTT and Kafka high concurrency scenario according to claim 1, wherein the sending the filtered data to an MQTT server, and storing the filtered data in different topics specifically comprises:
at a consumption end of Kafka, consuming messages stored in a Kafka Broker partition in advance one by one, and extracting a Key of each message, wherein the Key comprises a sender ID and a receiver ID of the message;
when the release Message specifies Topic, the ID of the receiver is required to be used as the parent Topic of the ID of the sender, and the ID of the sender is added in front of the Message Body so as to be convenient for the analysis of the receiving end;
the receiver subscribes to the Topic with the self ID as the first level after starting, and receives all messages with the self ID as the first level by using a wildcard; after parsing the Message Body of the received Message, the sending source of the Message content is identified.
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| CN109617985B (en) * | 2018-12-26 | 2022-06-10 | 布兰图智慧科技有限公司 | Method and system for processing data by concurrent MQTT gateway |
| CN109756417B (en) * | 2019-01-04 | 2022-08-30 | 平安科技（深圳）有限公司 | Offline message distribution method, server and storage medium |
| CN110008272B (en) * | 2019-04-10 | 2020-01-31 | 张绿儿 | NoSQL database evaluation system for sensor data and construction method thereof |
| CN111818112B (en) * | 2019-04-11 | 2022-10-04 | 中国移动通信集团四川有限公司 | Kafka system-based message sending method and device |
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| CN110278248B (en) * | 2019-05-29 | 2022-04-22 | 平安科技（深圳）有限公司 | Method and device for distributing testament information and computer readable storage medium |
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| CN110635970A (en) * | 2019-10-10 | 2019-12-31 | 武汉普利商用机器有限公司 | Internet of things equipment online state identification method, online information platform and server |
| CN113133027B (en) * | 2019-12-30 | 2023-01-20 | Tcl新技术（惠州）有限公司 | Communication method, server, terminal and communication system |
| CN111935028B (en) * | 2020-09-21 | 2021-01-08 | 浙江百应科技有限公司 | IOT cluster communication method based on routing mode and MQTT protocol |
| CN112269661B (en) * | 2020-10-30 | 2022-04-15 | 上海哔哩哔哩科技有限公司 | Partition migration method and device based on Kafka cluster |
| CN112328684A (en) * | 2020-11-03 | 2021-02-05 | 浪潮云信息技术股份公司 | Method for synchronizing time sequence data to Kafka in real time based on OpenTsdb |
| CN112929430B (en) * | 2021-01-29 | 2023-01-03 | 光控特斯联(上海)信息科技有限公司 | Data transmission method and system based on communication of Internet of things |
| CN112583941B (en) * | 2021-02-24 | 2021-05-28 | 国网江苏省电力有限公司信息通信分公司 | Method for supporting access of multiple power terminals, unit node and power Internet of things |
| CN113157449A (en) * | 2021-04-16 | 2021-07-23 | 上海寰果信息科技有限公司 | Real-time stream data analysis processing method based on MQTT |
| CN113206872B (en) * | 2021-04-22 | 2022-06-03 | 深圳感臻智能股份有限公司 | Message sending method, terminal and computer storage medium |
| CN113420048A (en) * | 2021-05-19 | 2021-09-21 | 中交公规土木大数据信息技术（北京）有限公司 | Data aggregation method and device, electronic equipment and storage medium |
| CN113709263B (en) * | 2021-11-01 | 2022-03-18 | 深圳市城市交通规划设计研究中心股份有限公司 | Data access method of Internet of things protocol MQTT, computer and storage medium |
| CN116112570A (en) * | 2021-11-10 | 2023-05-12 | 青岛海尔科技有限公司 | Message processing method, device, electronic equipment and storage medium |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106130882A (en) * | 2016-07-13 | 2016-11-16 | 北京百度网讯科技有限公司 | For the method and apparatus transmitting message |
-
2018
- 2018-05-16 CN CN201810465578.2A patent/CN108768826B/en not_active Expired - Fee Related
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106130882A (en) * | 2016-07-13 | 2016-11-16 | 北京百度网讯科技有限公司 | For the method and apparatus transmitting message |
Non-Patent Citations (4)
| Title |
|---|
| Designing of IoT Platform Based on Functional Reactive Pattern;Haidong Lv等;《Proceedings of 2018 International Conference on Computer Science, Electronics and Communication Engineering（CSECE2018）》;20180207;正文446-447页 * |
| 云环境下消息传输机制的研究与设计;罗今;《中国优秀硕士学位论文全文数据库》;20180415;全文 * |
| 基于Kafka的消息队列在射天文数据处理中应用的研究;王郑合;《中国优秀硕士学位论文全文数据库》;20180115;正文第10-39页 * |
| 面向工业大数据的数据采集系统;谢青松;《中国优秀硕士学位论文全文数据库》;20180115;正文第30-32页 * |
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