java - merge many application.properties files instead of replace on Spring Boot?

Question

i am using Spring Booot MVC 1.2.2.RELEASE. I have my multi-module project which is structured like this:

example-backend-development(parent)
---> example-backend-development-domain
---> example-backend-development-service

I want to make both modules independent, or at least domain from service, since service has domain module in its classpath. So both modules have their application.properties file in their respective resources folder. I want to do it like this way because i don't want to handle all properties from service module (e.g Jpa properties, which belongs to domain module).

So for example i have this application.properties in service module

logging.level.org.springframework.web: DEBUG
logging.level.org.hibernate: ERROR
logging.level.com.example.movies: DEBUG

And this one in domain module

spring.datasource.driverClassName=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/sarasa_db
spring.datasource.username=root
spring.datasource.password=mypassword

spring.jpa.hibernate.ddl-auto=update
spring.jpa.hibernate.dialect=org.hibernate.dialect.MySQL5Dialect
spring.jpa.show-sql=true

The problem is that when i boot my service, as they both application.properties are in the service classpath, then it replace the application.properties from service with the other one from domain. And i want to merge them if they have the same name, as this case. Here the spring logs (DEBUG+INFO)

 :: Spring Boot ::        (v1.2.2.RELEASE)

2015-05-12 15:06:24.794 DEBUG 7728 --- [           main] o.s.w.c.s.StandardServletEnvironment     : Adding [servletConfigInitParams] PropertySource with lowest search precedence
2015-05-12 15:06:24.797 DEBUG 7728 --- [           main] o.s.w.c.s.StandardServletEnvironment     : Adding [servletContextInitParams] PropertySource with lowest search precedence
2015-05-12 15:06:24.798 DEBUG 7728 --- [           main] o.s.w.c.s.StandardServletEnvironment     : Adding [systemProperties] PropertySource with lowest search precedence
2015-05-12 15:06:24.798 DEBUG 7728 --- [           main] o.s.w.c.s.StandardServletEnvironment     : Adding [systemEnvironment] PropertySource with lowest search precedence
2015-05-12 15:06:24.798 DEBUG 7728 --- [           main] o.s.w.c.s.StandardServletEnvironment     : Initialized StandardServletEnvironment with PropertySources [servletConfigInitParams,servletContextInitParams,systemProperties,systemEnvironment]
2015-05-12 15:06:24.840  INFO 7728 --- [           main] c.e.movies.service.ApplicationRunner     : Starting ApplicationRunner on despubuntu-ThinkPad-E420 with PID 7728 (/home/despubuntu/Documents/Workspace/example-backend-development/example-backend-development/example-backend-development-service/target/classes started by despubuntu in /home/despubuntu/Documents/Workspace/example-backend-development/example-backend-development/example-backend-development-service)
2015-05-12 15:06:24.841 DEBUG 7728 --- [           main] c.e.movies.service.ApplicationRunner     : Running with Spring Boot v1.2.2.RELEASE, Spring v4.1.6.RELEASE
2015-05-12 15:06:24.915  INFO 7728 --- [           main] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@55782201: startup date [Tue May 12 15:06:24 ART 2015]; root of context hierarchy
2015-05-12 15:06:25.034 DEBUG 7728 --- [           main] o.s.w.c.s.StandardServletEnvironment     : Adding [class path resource [application.properties]] PropertySource with lowest search precedence
2015-05-12 15:06:25.083 DEBUG 7728 --- [           main] o.s.w.c.s.StandardServletEnvironment     : Replacing [class path resource [application.properties]] PropertySource with [class path resource [application.properties]]
2015-05-12 15:06:26.033  INFO 7728 --- [           main] o.s.b.f.s.DefaultListableBeanFactory     : Overriding bean definition for bean 'beanNameViewResolver': replacing [Root bean: class [null]; scope=; abstract=false; lazyInit=false; autowireMode=3; dependencyCheck=0; autowireCandidate=true; primary=false; factoryBeanName=org.springframework.boot.autoconfigure.web.ErrorMvcAutoConfiguration$WhitelabelErrorViewConfiguration; factoryMethodName=beanNameViewResolver; initMethodName=null; destroyMethodName=(inferred); defined in class path resource [org/springframework/boot/autoconfigure/web/ErrorMvcAutoConfiguration$WhitelabelErrorViewConfiguration.class]] with [Root bean: class [null]; scope=; abstract=false; lazyInit=false; autowireMode=3; dependencyCheck=0; autowireCandidate=true; primary=false; factoryBeanName=org.springframework.boot.autoconfigure.web.WebMvcAutoConfiguration$WebMvcAutoConfigurationAdapter; factoryMethodName=beanNameViewResolver; initMethodName=null; destroyMethodName=(inferred); defined in class path resource [org/springframework/boot/autoconfigure/web/WebMvcAutoConfiguration$WebMvcAutoConfigurationAdapter.class]]
2015-05-12 15:06:26.753 DEBUG 7728 --- [           main] o.s.w.c.s.StandardServletEnvironment     : Adding [applicationConfig: [classpath:/application.properties]] PropertySource with search precedence immediately lower than [applicationConfigurationProperties]
2015-05-12 15:06:26.753 DEBUG 7728 --- [           main] o.s.w.c.s.StandardServletEnvironment     : Removing [applicationConfigurationProperties] PropertySource
2015-05-12 15:06:26.753 DEBUG 7728 --- [           main] o.s.w.c.s.StandardServletEnvironment     : Removing [defaultProperties] PropertySource
2015-05-12 15:06:27.178  INFO 7728 --- [           main] trationDelegate$BeanPostProcessorChecker : Bean 'spring.datasource.CONFIGURATION_PROPERTIES' of type [class org.springframework.boot.autoconfigure.jdbc.DataSourceProperties] is not eligible for getting processed by all BeanPostProcessors (for example: not eligible for auto-proxying)
2015-05-12 15:06:27.179  INFO 7728 --- [           main] trationDelegate$BeanPostProcessorChecker : Bean 'org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration$NonEmbeddedConfiguration' of type [class org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration$NonEmbeddedConfiguration] is not eligible for getting processed by all BeanPostProcessors (for example: not eligible for auto-proxying)
2015-05-12 15:06:27.473  INFO 7728 --- [           main] trationDelegate$BeanPostProcessorChecker : Bean 'dataSource' of type [class org.apache.tomcat.jdbc.pool.DataSource] is not eligible for getting processed by all BeanPostProcessors (for example: not eligible for auto-proxying)
2015-05-12 15:06:27.474  INFO 7728 --- [           main] trationDelegate$BeanPostProcessorChecker : Bean 'com.example.movies.domain.config.PersistenceConfiguration' of type [class com.example.movies.domain.config.PersistenceConfiguration$$EnhancerBySpringCGLIB$$1afe0f6c] is not eligible for getting processed by all BeanPostProcessors (for example: not eligible for auto-proxying)
2015-05-12 15:06:27.665  INFO 7728 --- [           main] trationDelegate$BeanPostProcessorChecker : Bean 'org.springframework.transaction.annotation.ProxyTransactionManagementConfiguration' of type [class org.springframework.transaction.annotation.ProxyTransactionManagementConfiguration$$EnhancerBySpringCGLIB$$8c497c14] is not eligible for getting processed by all BeanPostProcessors (for example: not eligible for auto-proxying)
2015-05-12 15:06:27.812  INFO 7728 --- [           main] trationDelegate$BeanPostProcessorChecker : Bean 'transactionAttributeSource' of type [class org.springframework.transaction.annotation.AnnotationTransactionAttributeSource] is not eligible for getting processed by all BeanPostProcessors (for example: not eligible for auto-proxying)
2015-05-12 15:06:27.823  INFO 7728 --- [           main] trationDelegate$BeanPostProcessorChecker : Bean 'transactionInterceptor' of type [class org.springframework.transaction.interceptor.TransactionInterceptor] is not eligible for getting processed by all BeanPostProcessors (for example: not eligible for auto-proxying)
2015-05-12 15:06:27.827  INFO 7728 --- [           main] trationDelegate$BeanPostProcessorChecker : Bean 'org.springframework.transaction.config.internalTransactionAdvisor' of type [class org.springframework.transaction.interceptor.BeanFactoryTransactionAttributeSourceAdvisor] is not eligible for getting processed by all BeanPostProcessors (for example: not eligible for auto-proxying)
2015-05-12 15:06:28.350  INFO 7728 --- [           main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat initialized with port(s): 8080 (http)
2015-05-12 15:06:28.737  INFO 7728 --- [           main] o.apache.catalina.core.StandardService   : Starting service Tomcat
2015-05-12 15:06:28.739  INFO 7728 --- [           main] org.apache.catalina.core.StandardEngine  : Starting Servlet Engine: Apache Tomcat/8.0.20
2015-05-12 15:06:28.873  INFO 7728 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
2015-05-12 15:06:28.873 DEBUG 7728 --- [ost-startStop-1] o.s.web.context.ContextLoader            : Published root WebApplicationContext as ServletContext attribute with name [org.springframework.web.context.WebApplicationContext.ROOT]
2015-05-12 15:06:28.873  INFO 7728 --- [ost-startStop-1] o.s.web.context.ContextLoader            : Root WebApplicationContext: initialization completed in 3962 ms
2015-05-12 15:06:29.077 DEBUG 7728 --- [ost-startStop-1] o.s.w.c.s.StandardServletEnvironment     : Adding [servletConfigInitParams] PropertySource with lowest search precedence
2015-05-12 15:06:29.077 DEBUG 7728 --- [ost-startStop-1] o.s.w.c.s.StandardServletEnvironment     : Adding [servletContextInitParams] PropertySource with lowest search precedence
2015-05-12 15:06:29.078 DEBUG 7728 --- [ost-startStop-1] o.s.w.c.s.StandardServletEnvironment     : Adding [systemProperties] PropertySource with lowest search precedence
2015-05-12 15:06:29.078 DEBUG 7728 --- [ost-startStop-1] o.s.w.c.s.StandardServletEnvironment     : Adding [systemEnvironment] PropertySource with lowest search precedence
2015-05-12 15:06:29.079 DEBUG 7728 --- [ost-startStop-1] o.s.w.c.s.StandardServletEnvironment     : Initialized StandardServletEnvironment with PropertySources [servletConfigInitParams,servletContextInitParams,systemProperties,systemEnvironment]
2015-05-12 15:06:29.132 DEBUG 7728 --- [ost-startStop-1] o.s.w.c.s.StandardServletEnvironment     : Adding [servletConfigInitParams] PropertySource with lowest search precedence
2015-05-12 15:06:29.132 DEBUG 7728 --- [ost-startStop-1] o.s.w.c.s.StandardServletEnvironment     : Adding [servletContextInitParams] PropertySource with lowest search precedence
2015-05-12 15:06:29.133 DEBUG 7728 --- [ost-startStop-1] o.s.w.c.s.StandardServletEnvironment     : Adding [systemProperties] PropertySource with lowest search precedence
2015-05-12 15:06:29.133 DEBUG 7728 --- [ost-startStop-1] o.s.w.c.s.StandardServletEnvironment     : Adding [systemEnvironment] PropertySource with lowest search precedence
2015-05-12 15:06:29.133 DEBUG 7728 --- [ost-startStop-1] o.s.w.c.s.StandardServletEnvironment     : Initialized StandardServletEnvironment with PropertySources [servletConfigInitParams,servletContextInitParams,systemProperties,systemEnvironment]
2015-05-12 15:06:29.746  INFO 7728 --- [ost-startStop-1] o.s.b.c.e.ServletRegistrationBean        : Mapping servlet: 'dispatcherServlet' to [/]
2015-05-12 15:06:29.751  INFO 7728 --- [ost-startStop-1] o.s.b.c.embedded.FilterRegistrationBean  : Mapping filter: 'characterEncodingFilter' to: [/*]
2015-05-12 15:06:29.751  INFO 7728 --- [ost-startStop-1] o.s.b.c.embedded.FilterRegistrationBean  : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]
2015-05-12 15:06:29.781 DEBUG 7728 --- [ost-startStop-1] o.s.web.filter.HiddenHttpMethodF

Answer 1

Assuming You are booting your application from example-backend-development-service, I would suggest doing the following

Rename application.propertiesin example-backend-development-domainto `domainapplication.properties. While Booting Your application, Override the property configuration as shown below. I tested this and it does work for me.

 /**
     * Hello world!
     *
     */
    @SpringBootApplication
    @PropertySource(value = { "application.properties","domainapplication.properties" })
    public class App 
    {
        @Autowired
        private ModuleService moduleService;
        public static void main(String[] args) throws Exception {
            ApplicationContext applicationContext= SpringApplication.run(App.class, args);
            ModuleService moduleService = (ModuleService) applicationContext.getBean(ModuleService.class);
            System.out.println(moduleService.getProp());
            String[] beanNames = applicationContext.getBeanDefinitionNames();
            Arrays.sort(beanNames);
            for (String beanName : beanNames) {
                System.out.println(beanName);
            }
        }
    }

EDIT:-

If you are booting from domain as well just use the following in the reference here

If you don’t like application.properties as the configuration file name you can switch to another by specifying a spring.config.name environment property. You can also refer to an explicit location using the spring.config.location environment property (comma-separated list of directory locations, or file paths).

$ java -jar myproject.jar --spring.config.name=myproject

or

$ java -jar myproject.jar --spring.config.location=classpath:/default.properties,classpath:/override.properties