How to log the active configuration in a Spring Boot application?

Question

I would really like to use YAML config for Spring Boot, as I find it quite readable and useful to have a single file showing what properties are active in my different profi

Answer 1

Actuator /env service displays properties, but it doesn't displays which property value is actually active. Very often you may want to override your application properties with

• profile-specific application properties
• command line arguments
• OS environment variables

Thus you will have the same property and different values in several sources.

Snippet bellow prints active application properties values on startup:

@Configuration
public class PropertiesLogger {
    private static final Logger log = LoggerFactory.getLogger(PropertiesLogger.class);

    @Autowired
    private AbstractEnvironment environment;

    @PostConstruct
    public void printProperties() {

        log.info("**** APPLICATION PROPERTIES SOURCES ****");

        Set properties = new TreeSet<>();
        for (PropertiesPropertySource p : findPropertiesPropertySources()) {
            log.info(p.toString());
            properties.addAll(Arrays.asList(p.getPropertyNames()));
        }

        log.info("**** APPLICATION PROPERTIES VALUES ****");
        print(properties);

    }

    private List findPropertiesPropertySources() {
        List propertiesPropertySources = new LinkedList<>();
        for (PropertySource propertySource : environment.getPropertySources()) {
            if (propertySource instanceof PropertiesPropertySource) {
                propertiesPropertySources.add((PropertiesPropertySource) propertySource);
            }
        }
        return propertiesPropertySources;
    }

    private void print(Set properties) {
        for (String propertyName : properties) {
            log.info("{}={}", propertyName, environment.getProperty(propertyName));
        }
    }

}