Multi-context spring-boot application: how to define standard spring-boot properties for each child context

Question

There is good question about ability to add multiple tomcat connectors and bind them to separate controllers each.

The essense of Andy Wilkinson\'s good answer is he

Answer 1

You can achieve your first suggestion using spring.config.name:

public static void main(String[] args) {
    SpringApplicationBuilder parentBuilder =
            new SpringApplicationBuilder(ParentApplication.class)
                    .web(WebApplicationType.NONE);
    parentBuilder.run(args);
    parentBuilder.child(ServiceOneConfiguration.class)
            .properties("spring.config.name=child1").run(args);
    parentBuilder.child(ServiceTwoConfiguration.class)
            .properties("spring.config.name=child2").run(args);
}

You can then use child1{-profile}.properties and child2{-profile}.properties to configure service one and service two respectively.

For example, with server.port=8081 in child1.properties and server.port=8082 in child2.properties, you should see output similar to the following when starting an app that's using auto-configuration in the two child services and has a dependency on spring-boot-starter-web:

  .   ____          _            __ _ _
 /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
 \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::        (v2.1.2.RELEASE)

2019-01-22 13:38:09.690  INFO 80968 --- [           main] com.example.parent.ParentApplication     : Starting ParentApplication on …
2019-01-22 13:38:09.692  INFO 80968 --- [           main] com.example.parent.ParentApplication     : No active profile set, falling back to default profiles: default
2019-01-22 13:38:09.842  INFO 80968 --- [           main] com.example.parent.ParentApplication     : Started ParentApplication in 0.371 seconds (JVM running for 0.644)

  .   ____          _            __ _ _
 /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
 \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::        (v2.1.2.RELEASE)

2019-01-22 13:38:10.046  INFO 80968 --- [           main] com.example.parent.ParentApplication     : No active profile set, falling back to default profiles: default
2019-01-22 13:38:10.584  INFO 80968 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat initialized with port(s): 8081 (http)
2019-01-22 13:38:10.604  INFO 80968 --- [           main] o.apache.catalina.core.StandardService   : Starting service [Tomcat]
2019-01-22 13:38:10.605  INFO 80968 --- [           main] org.apache.catalina.core.StandardEngine  : Starting Servlet engine: [Apache Tomcat/9.0.14]
2019-01-22 13:38:10.613  INFO 80968 --- [           main] o.a.catalina.core.AprLifecycleListener   : The APR based Apache Tomcat Native library which allows optimal performance in production environments was not found on the java.library.path: [/Users/awilkinson/Library/Java/Extensions:/Library/Java/Extensions:/Network/Library/Java/Extensions:/System/Library/Java/Extensions:/usr/lib/java:.]
2019-01-22 13:38:10.668  INFO 80968 --- [           main] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
2019-01-22 13:38:10.668  INFO 80968 --- [           main] o.s.web.context.ContextLoader            : Root WebApplicationContext: initialization completed in 612 ms
2019-01-22 13:38:10.829  INFO 80968 --- [           main] o.s.s.concurrent.ThreadPoolTaskExecutor  : Initializing ExecutorService 'applicationTaskExecutor'
2019-01-22 13:38:10.981  INFO 80968 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat started on port(s): 8081 (http) with context path ''
2019-01-22 13:38:10.981  INFO 80968 --- [           main] com.example.parent.ParentApplication     : Started ParentApplication in 0.955 seconds (JVM running for 1.784)

  .   ____          _            __ _ _
 /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
 \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::        (v2.1.2.RELEASE)

2019-01-22 13:38:11.003  INFO 80968 --- [           main] com.example.parent.ParentApplication     : No active profile set, falling back to default profiles: default
2019-01-22 13:38:11.093  INFO 80968 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat initialized with port(s): 8082 (http)
2019-01-22 13:38:11.095  INFO 80968 --- [           main] o.apache.catalina.core.StandardService   : Starting service [Tomcat]
2019-01-22 13:38:11.096  INFO 80968 --- [           main] org.apache.catalina.core.StandardEngine  : Starting Servlet engine: [Apache Tomcat/9.0.14]
2019-01-22 13:38:11.100  INFO 80968 --- [           main] o.a.c.c.C.[Tomcat-1].[localhost].[/]     : Initializing Spring embedded WebApplicationContext
2019-01-22 13:38:11.101  INFO 80968 --- [           main] o.s.web.context.ContextLoader            : Root WebApplicationContext: initialization completed in 97 ms
2019-01-22 13:38:11.135  INFO 80968 --- [           main] o.s.s.concurrent.ThreadPoolTaskExecutor  : Initializing ExecutorService 'applicationTaskExecutor'
2019-01-22 13:38:11.164  INFO 80968 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat started on port(s): 8082 (http) with context path ''
2019-01-22 13:38:11.165  INFO 80968 --- [           main] com.example.parent.ParentApplication     : Started ParentApplication in 0.183 seconds (JVM running for 1.967)