Spring Boot integrates RocketMQ to realize normal, delay, transaction message sending and receiving, PULL consumption mode and enable ACL | Spring Cloud 30

1. Foreword In the previous section, we had a basic understanding of RocketMQ through the following chapters: docker-compose builds RocketMQ 5.1.0 cluster (dual master and dual slave mode) | Spring Cloud 28 docker-compose build RocketMQ 5.1.0 cluster to enable ACL permission control | Spring Cloud 29 Now let’s formally study the integration of RocketMQ in […]

[RocketMQ] Automatic fault recovery cluster practice based on RocketMQ 5.1.0 version (Controller embedded mode)

Article directory need Prepare nameserver dashboard Broker exporter problems encountered write at the end Requirements RocketMQ version is 5.1.0; Build a cluster of 3 masters and 3 slaves, adopt cross-deployment (to avoid two machines being master-slave each other), and save machine resources; 3 nameservers, 1 exporter, 1 dashboard; Supports automatic fault recovery, and the controller […]

Rocketmq-Mqtt development example

Doker official website: Doker 1. RocketMQ MQTT Overview The traditional message queue MQ is mainly used for message communication between services (ends), such as transaction messages, payment messages, logistics messages, etc. in the e-commerce field. However, under the general category of messages, there is another very important and common message field, that is, IoT terminal […]

C51 single-chip microcomputer development heart-shaped lamp water lamp (C language)

Using the Keil uVision4 programming program, create a simulation circuit in Proteus 8 Professional Simulation circuit Hexadecimal style pattern int a[][8] = { 0x01,0x02,0x04,0x08,0x10,0x20,0x40,0x80, 0x03,0x06,0x0c,0x18,0x30,0x60,0xc0,0x80, 0x07,0x0e,0x1c,0x38,0x70,0xe0,0xc0,0x80, 0x0f, 0x1e, 0x3c, 0x78, 0xf0, 0xe0, 0xc0, 0x80, 0xfc,0xf9,0xf3,0xe7,0xcf,0x9f,0x3f,0x7f, }; Delay function void delay(unsigned int x) { while(x–); } Loop call function led1() refers to operate the P0 port, […]

Linux– Process priority and environment variables

Directory process priority basic concept How to check priority PRI and NI NI value setting range How to modify the NI value Modification method 1: Modify the priority through the top command Modification method 2: Modify the priority through the renice command Four important concepts of process environment variable basic concept Common Environment Variables View […]

Overview of the Spring MVC startup process

Spring MVC is a Java-based web framework that provides an MVC (Model-View-Controller)-based architectural pattern that helps developers build web applications more easily. In this article, we will delve into the startup process and initialization process of Spring MVC. Key steps Load configuration file: The configuration file of Spring MVC is generally in XML format, and […]

Problems encountered in spark production process (accumulator related)

Project scenario: Hint: Here is a brief background on the project: Project scenario: spark upsert mysql data, and want to control the process through the result of foreachpartition execution. Description of the problem def insertOrUpdateDFtoDB(tableName: String, resultDateFrame: DataFrame, updateColumns: Array[String]): Boolean = {<!– –> var count = 0 var status = true val colNumbsers = […]

Configure VSCode to track and debug the Linux kernel startup process

Configure VSCode Install the VSCode plugins C/C++ Intellisense and C/C++ Themes. Since the plug-in C/C++ Intellisense requires GNU Global, you also need to install GNUGlobal using the following command. sudo apt install global Modify the .vscode configuration item, refer to https://github.com/mengning/linuxkernel/tree/master/src/kerneldebuging, Since the Linux kernel is highly customized, there is no way to make Intellisense […]