Spring Cloud 拉取 Nacos 中配置文件

一.读取配置文件流程

1.程序启动首先读取应用中bootstarp.yml配置文件
2.再到 nacos 读取 DEFAULT_GROUP 默认分组下的
  application-${spring.profiles.active}.${spring.cloud.nacos.config.file-extension} 配置文件。
  例如：application-dev.yml
3.最后到 nacos 读取 ${spring.cloud.nacos.config.group} 配置分组下的
  ${spring.application.name}.${spring.cloud.nacos.config.file-extension} 配置文件。
  例如：kafka-test-dev.yml

二.配置bootstrap.yml文件

server:
  port: 8888
spring:
  profiles:
    active: @profiles.active@
  application:
    name: @artifactId@
  cloud:
    nacos:
      #nacos配置中心（将应用服务注册到nacos中）
      discovery:
        server-addr: localhost:8848
        # 分组
        group: TEST_DEMO
        # 命名空间
        namespace: b3d6b8c4-e85c-4935-9b05-d1b512891a1b
      #nacos注册中心（从nacos中拉取配置文件）
      config:
        server-addr: localhost:8848
        # 指定配置文件后缀名
        file-extension: yml
        group: TEST_DEMO
        namespace: b3d6b8c4-e85c-4935-9b05-d1b512891a1b
        # 指定读取共享配置文件名称，多个使用逗号隔开
        shared-dataids: application-${spring.profiles.active}.${spring.cloud.nacos.config.file-extension}
        # 指定哪些共享配置文件支持动态刷新，多个使用逗号隔开
        refreshable-dataids: application-${spring.profiles.active}.${spring.cloud.nacos.config.file-extension}

ps: 如果读取不到@@值，在maven的pom文件配置以下插件即可

<build>
  <plugins>
    <plugin>
      <groupId>org.apache.maven.plugins</groupId>
      <artifactId>maven-resources-plugin</artifactId>
      <configuration>
        <delimiters>@</delimiters>
        <useDefaultDelimiters>false</useDefaultDelimiters>
      </configuration>
    </plugin>
  </plugins>
  <resources>
    <resource>
      <directory>src/main/resources</directory>
      <filtering>true</filtering>
    </resource>
  </resources>
</build>

三.配置pom.xml文件

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.kafka.test</groupId>
    <artifactId>kafka-test</artifactId>
    <version>1.0-SNAPSHOT</version>

    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
        <lombok.version>1.18.10</lombok.version>
        <spring-boot.version>2.4.2</spring-boot.version>
        <spring-cloud.version>2020.0.1</spring-cloud.version>
        <spring-cloud-alibaba.version>2021.1</spring-cloud-alibaba.version>
    </properties>

    <dependencies>
	<!--bootstrap 启动器-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-bootstrap</artifactId>
        </dependency>
        <!-- spring-boot 启动器 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <!--测试依赖-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>

        <!--注册中心客户端-->
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
        </dependency>

        <!--配置中心客户端-->
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId>
        </dependency>

        <!--kafka 依赖-->
        <dependency>
            <groupId>org.springframework.kafka</groupId>
            <artifactId>spring-kafka</artifactId>
        </dependency>

        <!--Springboot集成 Redis ，Springboot2.x默认是用Lettuce连接redis，Lettuce可伸缩，线程安全-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-redis</artifactId>
        </dependency>

    </dependencies>

    <dependencyManagement>
        <dependencies>
            <!-- spring boot 依赖 -->
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-dependencies</artifactId>
                <version>${spring-boot.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
            <!-- spring cloud 依赖 -->
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
            <!-- spring cloud alibaba 依赖 -->
            <dependency>
                <groupId>com.alibaba.cloud</groupId>
                <artifactId>spring-cloud-alibaba-dependencies</artifactId>
                <version>${spring-cloud-alibaba.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <profiles>
        <profile>
            <id>dev</id>
            <properties>
                <profiles.active>dev</profiles.active>
            </properties>
            <activation>
                <activeByDefault>true</activeByDefault>
            </activation>
        </profile>
    </profiles>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-resources-plugin</artifactId>
                <configuration>
                    <delimiters>@</delimiters>
                    <useDefaultDelimiters>false</useDefaultDelimiters>
                </configuration>
            </plugin>
        </plugins>
        <resources>
            <resource>
                <directory>src/main/resources</directory>
                <filtering>true</filtering>
            </resource>
        </resources>
    </build>
</project>

四.在nacos中配置application-${spring.profiles.active}.${spring.cloud.nacos.config.file-extension}文件

例如：application-dev.yml

spring:
  #kafka
  kafka:
    bootstrap-servers: localhost:9092
    producer:
      retries: 0
      batch-size: 16384
      buffer-memory: 33554432
      acks: 1
    consumer:
      group-id: TestGroup
      auto-offset-reset: earliest
      enable-auto-commit: true
      auto-commit-interval: 5000
      key-deserializer: org.apache.kafka.common.serialization.StringDeserializer
      value-deserializer: org.apache.kafka.common.serialization.StringDeserializer
    listener:
      concurrency: 3

  #redis
  redis:
    host: 127.0.0.1
    port: 6379
    maxIdle: 8
    minIdle: 4
    maxTotal: 8
    maxWaitMillis: 6000
    timeOut: 6000

六.配置${spring.application.name}-${spring.profiles.active}.${spring.cloud.nacos.config.file-extension} 文件

例如：kafka-test-dev.yml

user:
  name: zhangsan
  email: 1100000@qq.com