Spring Cloud Alibaba为阿里巴巴中间件的分布式解决方案提供一站式应用开发解决方案

# Spring Cloud Alibaba Nacos Example ## Project description This project demonstrates how to use Spring Cloud Alibaba Nacos related Starters to complete the service discovery and configuration management of Spring Cloud applications. [Nacos](https://github.com/alibaba/Nacos) It is Alibaba's open source dynamic service discovery, configuration management and service management platform that is easier to build cloud-native applications. ## Nacos Server 2.3.2 is properly configured and started In Nacos 2.3.2, functions related to user authentication are added. When starting Nacos Server for the first time, it needs to be configured correctly to avoid the problem of startup failure. ### Download Nacos Server > The Nacos serv version used in this example is 2.2.3! Nacos supports both direct download and source code construction. **Nacos Server version 2.2.3 is recommended for Spring Cloud Alibaba 2022.x.** 1. Direct download: [Nacos Server download page](https://github.com/alibaba/nacos/releases) 2. Source code construction: Enter Nacos [Github project page](https://github.com/alibaba/nacos), git clone the code to the local compilation and packaging [参考文档](https://nacos.io/zh-cn/docs/quick-start.html). ### Configure the Nacos Server Open the `\nacos-server-2.2.3\conf\application.properties` configuration file and modify the following configuration items: #### Configure the data source Take the MySQL database as an example here, and use the `nacos-server-2.2.3\conf\mysql-schema.sql` initialization database table file. Modify the following configuration as well ```properties #*************** Config Module Related Configurations ***************# ### If use MySQL as datasource: spring.datasource.platform=mysql ### Count of DB: db.num=1 ### Connect URL of DB: db.url.0=jdbc:mysql://127.0.0.1:3306/nacos?characterEncoding=utf8&connectTimeout=1000&socketTimeout=3000&autoReconnect=true&useUnicode=true&useSSL=false&serverTimezone=UTC&allowPublicKeyRetrieval=true db.user.0=root db.password.0=root ### Connection pool configuration: hikariCP db.pool.config.connectionTimeout=30000 db.pool.config.validationTimeout=10000 db.pool.config.maximumPoolSize=20 db.pool.config.minimumIdle=2 ``` #### Turn on authentication **Note: If it is not enabled, login failure exception will occur in 2.3.2!** ```properties ### The auth system to use, currently only 'nacos' and 'ldap' is supported: nacos.core.auth.system.type=nacos ### If turn on auth system: nacos.core.auth.enabled=true ``` #### Set the server authentication key ```properties nacos.core.auth.server.identity.key=test nacos.core.auth.server.identity.value=test ``` #### Set the default token ```properties ### The default token (Base64 String): nacos.core.auth.plugin.nacos.token.secret.key=SecretKey012345678901234567890123456789012345678901234567890123456789 ``` ** When using the Nacos service discovery and configuration function, be sure to configure `username` and `password` attribute, otherwise the user will not be found! ** #### Open API authentication Authentication is required when using the Open api interface in nacos server 2.3.2: For more details, please refer to: [Nacos api authentication](https://nacos.io/zh-cn/docs/auth.html) 1. Obtain accessToken: Use username and password to log in to the nacos server: `curl -X POST '127.0.0.1:8848/nacos/v1/auth/login' -d 'username=nacos&password=nacos'` If the username and password are correct, the returned information is as follows: `{"accessToken":"eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiJuYWNvcyIsImV4cCI6MTYwNTYyOTE2Nn0.2TogGhhr11_vLEjqKko1HJHUJEmsPuCxkur-CfNojDo", "tokenTtl": 18000, "globalAdmin": true}` 2. Use accessToken to request the nacos api interface: `curl -X GET '127.0.0.1:8848/nacos/v1/cs/configs?accessToken=eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiJuYWNvcyIsImV4cCI6MTYwNTYyMzkyM30.O-s2yWfDSUZ7Svd3Vs7jy9tsfDNHs1SuebJB4KlNY8Q&dataId=nacos.example.1&group=nacos_group'` ### Start the Nacos Server 1. Start Nacos Server, enter the folder after downloading to the local and decompressing (enter the folder after compiling and packaging by using the source code construction method), then enter its relative folder `nacos/bin`, and execute the following command according to the actual situation of the operating system. [详情参考此文档](https://nacos.io/zh-cn/docs/quick-start.html)。 1. Linux/Unix/Mac operating system, execute the command `sh startup.sh -m standalone` 2. Windows operating system, executing command `cmd startup.cmd` 2. Access Nacos Server Console. The browser enters the address http://127.0.0.1:8848/nacos , **The first login needs to bind the nacos user, because the new version adds authentication, and the user name and password need to be configured during application registration and configuration binding.** ## Nacos application example ### Spring Cloud Alibaba Nacos Config #### Application access Before starting the application sample to demonstrate the project function, first understand how the Spring Cloud application accesses Nacos Config as the service configuration center. **Note that this section is only for the convenience of understanding the access method. The access work has been completed in this sample code, and no further modification is required.** 1. First, modify the `pom.xml` file to introduce spring-cloud-starter-alibaba-nacos-config; ```xml <dependency> <groupId>com.alibaba.cloud</groupId> <artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId> </dependency> ``` 2. Configuring a Nacos address in an `/src/main/resources/application.yaml` applied configuration file and introducing a service configuration; ```yml spring: cloud: nacos: serverAddr: 127.0.0.1:8848 username: 'nacos' password: 'nacos' config: import: - nacos:nacos-config-example.properties?refreshEnabled=true&group=DEFAULT_GROUP ``` 3. After completing the above two steps, the application will obtain the corresponding configuration from Nacos Server and add it to the Property Sources of Spring Environment. There are four ways to save a portion of the Nacos configuration using the Nacos Configuration Center: - BeanAutoRefres hConfig Example: An example of supporting automatic refresh of configuration changes by configuring configuration information as beans; - ConfigListenerEx ample: example of monitoring configuration information; - Docking Interface Example: An example of docking the Nacos interface and completing the addition, deletion, modification and query of the configuration information through the interface; - ValueAnnotation Example: An example of obtaining configuration information through the @ Value annotation. #### Add Configuration in Nacos Server Add a configuration to the Nacos Server by executing the following command from the command line. **Can be injected directly through the Nacos console!** ```shell $ curl -X POST "http://127.0.0.1:8848/nacos/v1/cs/configs?accessToken=XXXXXXXXXXXXXXXXXXXXXXXXXXX&dataId=nacos-config-example.properties&group=DEFAULT_GROUP&content=spring.cloud.nacos.config.serverAddr=127.0.0.1:8848%0Aspring.cloud.nacos.config.prefix=PREFIX%0Aspring.cloud.nacos.config.group=GROUP%0Aspring.cloud.nacos.config.namespace=NAMESPACE" ``` Details of the added configuration are as follows: ```properties # dataId is nacos-config-example.properties # group is DEFAULT_GROUP # content is: spring.cloud.nacos.config.serveraddr=127.0.0.1:8848 spring.cloud.nacos.config.prefix=PREFIX spring.cloud.nacos.config.group=GROUP spring.cloud.nacos.config.namespace=NAMESPACE ``` #### The application starts 1. Add configuration, and add basic configuration information in the application `/src/main/resources/application.yml`; ```yml server: port: 18084 management: endpoints: web: exposure: include: '*' ``` 2. Start th