指定Dev Profile启动Spring时仍加载Prod配置的问题

使用命令 ./mvnw -Pdev spring-boot:run 以Dev Profile启动Spring应用时，应用意外加载了Prod环境的配置，尝试连接不存在的mysql主机，抛出连接错误，不符合Dev环境仅加载对应配置的预期。

application.yaml 配置 #

spring:
  application:
    name: test
  profiles:
    active: '@profileActive@'

server:
  port: 8081

#dev config
---
spring:
  config:
    active:
      on-profile: dev
  jpa:
    hibernate:
      ddl-auto: update
    show-sql: true
  datasource:
    url: jdbc:mysql://localhost:3306/db
    username: root
    password: root
    driver-class-name: com.mysql.cj.jdbc.Driver

#prod config
---
spring:
  config:
    active:
      on-profile: prod
  jpa:
    hibernate:
      ddl-auto: update
    show-sql: true
  datasource:
    url: jdbc:mysql://mysql:3306/db
    username: root
    password: root
    driver-class-name: com.mysql.cj.jdbc.Driver

pom.xml 相关配置 #

<resources>
    <resource>
        <directory>src/main/resources</directory>
        <filtering>true</filtering>
        <includes>
            <include>**/*.yaml</include>
        </includes>
    </resource>
</resources>
</build>

<profiles>
    <profile>
        <id>dev</id>
        <activation>
            <activeByDefault>true</activeByDefault>
        </activation>
        <properties>
            <build.profile.id>dev</build.profile.id>
            <profileActivate>dev</profileActivate>
        </properties>
    </profile>
    <profile>
        <id>prod</id>
        <activation>
            <activeByDefault>false</activeByDefault>
        </activation>
        <properties>
            <build.profile.id>prod</build.profile.id>
            <profileActivate>prod</profileActivate>
        </properties>
    </profile>
</profiles>

你误用了spring.config.active.on-profile配置项，这个参数的作用是激活额外的配置文件，而非限定当前配置片段仅在对应Profile下生效。正确的Profile片段标识应该是spring.profiles，当前写法导致Prod的配置片段没有被正确限定，Spring会默认加载该片段，最终覆盖或合并了Dev的数据源配置。

修改application.yaml中的Profile标识，将spring.config.active.on-profile替换为spring.profiles，确保每个配置片段仅在对应Profile激活时加载：

spring:
  application:
    name: test
  profiles:
    active: '@profileActive@'

server:
  port: 8081

#dev config
---
spring:
  profiles: dev
  jpa:
    hibernate:
      ddl-auto: update
    show-sql: true
  datasource:
    url: jdbc:mysql://localhost:3306/db
    username: root
    password: root
    driver-class-name: com.mysql.cj.jdbc.Driver

#prod config
---
spring:
  profiles: prod
  jpa:
    hibernate:
      ddl-auto: update
    show-sql: true
  datasource:
    url: jdbc:mysql://mysql:3306/db
    username: root
    password: root
    driver-class-name: com.mysql.cj.jdbc.Driver

修改后重新执行./mvnw -Pdev spring-boot:run，应用只会加载Dev对应的配置片段，连接localhost上的MySQL，不会再加载Prod配置。

内容的提问来源于stack exchange，提问作者SlimenTN