Microservice Governance [Registration Discovery] Nacos

Table of contents

What is Nacos?

What is the use of Nacos?

use 

Flow chart of Nacos service discovery 

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What is Nacos?

        Nacos is a service discovery, configuration management, and service management platform open sourced by Alibaba. It is a dynamic service discovery and configuration management tool based on cloud-native architecture.

What is the use of Nacos?

        It provides core functions such as service registration and discovery, configuration management, DNS, and load balancing, which can help developers build and manage microservice architectures more conveniently.

 Access between microservices is discovered through the registration server 

        In the microservice architecture, there are usually two roles: service provider and service consumer. A service provider refers to a microservice application that provides a certain service. It can register its service instance information to the Nacos registry, so that service consumers can discover and invoke the service through the Nacos registry.

use 

1. Create a Nacos database and create a table to initialize data

Run the nacos-mysql.sql configuration file in the database

2. Configure in application.properties

Modify port number ip address database name password 

server.port=8848  #配置端口号 

 db.url.0=jdbc:mysql://127.0.0.1:3306/BroRiver_nacos?characterEncoding=utf8&connectTimeout=1000&socketTimeout=3000&autoReconnect=true&useUnicode=true&useSSL=false&serverTimezone=UTC
 db.user.0=root
 db.password.0=1234

start service 

Access the console Nacos address

• The default account is nacos and the password is nacos

 3. Introduce the coordinates of service discovery

<dependency>
   <groupId>com.alibaba.cloud</groupId>
   <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
   <version>2021.1</version>
</dependency>

4. Configure the Nacos address and name the application

spring:
  application:
    name: movieSys
  cloud:
    nacos:
      discovery:
        server-addr: 127.0.0.1:8848
        ip: 127.0.0.1

Parameter explanation:

name: movieSys

• (Identification) The name of the application

server-addr: 127.0.0.1:8848

• The address of the Nacos service discovery server, used to query application information from other services

ip: 127.0.0.1

• The IP address registered by the application on the Nacos service discovery server is used to allow other services to access the application through this IP address.
• If this property is not set, the application will use the default IP address (localhost's IP address) for registration.

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The core of Nacos service discovery is service registration and service discovery. The application registers its own service information in the service registry, and other services obtain service information by querying the service registry, and establish connections with the service.

Flow chart of Nacos service discovery 

        If the application's IP address or other information changes (for example, service upgrade or offline), it will send an update request to the Nacos service discovery server to update the service registration information. At the same time, other services will periodically send heartbeat requests to the Nacos service discovery server to ensure that they can receive status updates from other services.