Spring Boot 2.2.0 RC1 Release Notes

For changes in earlier milestones, please refer to:

Upgrading from Spring Boot 2.1 or 2.2.0.M6

See instructions in the 2.2.0.M1 release notes for upgrading from Spring Boot 2.1.

Constructor Binding for @ConfigurationProperties

Contructor binding for @ConfigurationProperties now needs to be explicitly declared using either @ImmutableConfigurationProperties or @ConstructorBinding.

In earlier milestone we attempted to deduce when constructor binding was required vs regular bean injection. Unfortuantely this turned out to be quite brittle and very hard to always get right so we’ve decided an explicit signal is required.

Micrometer 'New Relic' eventType

Micrometer 1.3 has changed the evenType that gets published with each metric to be a fixed value. This aligns with New Relic recommneded best practices.

Spring Boot 2.2 will use the value of management.metrics.export.newrelic.event-type as the eventType and add "metricName" and "metricType" attributes for context. If you don’t explicitly set an event type property then SpringBootSample is used.

If you perfer to use the previous behavor where the meter name was used as the eventType, you can set the management.metrics.export.newrelic.meter-name-event-type-enabled property to true.

Health Endpoint JSON

The /actuator/health endpoint has changed the resulting JSON format by renaming details to components for the first-level elements. This helps to differentiate the actual details retuned from a HealthIndicator from the component indicators that make up composite health.

As a result of the change, the actuator media type has been bumped from application/vnd.spring-boot.actuator.v2+json to application/vnd.spring-boot.actuator.v3+json.

If you have tools that need to consume the older format, you can use an HTTP Accept: header with the V2 media type, application/vnd.spring-boot.actuator.v2+json.

DevTools config directory

If you are using ~/.config/ for your DevTools properties you no longer need to prefix the file with .. You should now use ~/.config/spring-boot-devtools.properties or ~/.config/spring-boot-devtools.yml.

New and Noteworthy

Tip	Check the configuration changelog for a complete overview of the changes in configuration.

Banners

ASCII banner files can now make use of ANSI 256 color escape codes by using {AnsiColor.NNN} (where NNN is the color code).

You can also use them with image banners by setting the spring.banner.image.bitdepth property to 8. We’ve also added a spring.banner.image.pixelmode property that you can set to block to use ASCII block chars.

The result looks like this:

SAML Auto-configuration

Auto-configuration for Spring Security’s SAML 2.0 Relying Party is now available when its spring-security-saml2-server-provider module is on the classpath. Relying parties can be registered using the spring.security.saml2.relyingparty.registration.* properties.

RSocket Support

Auto-configuration for Spring Security’s RSocket integration is now available when its spring-security-rsocket module is on the classpath. The auto-configuration will enable RSocket security and configure the server RSocket factory with Spring Security’s interceptor.

When testing an RSocket server application, the local.rsocket.server.port property is now set to the port that the RSocket server is listening on. It can be injected into test classes using @LocalRSocketServerPort.

Lazy-init Programmatic Exclusions

If you set the new spring.main.lazy-initialization poperty to true you may face a situation where you needed it to back off for certain beans. This was previously only possible if you could change the @Bean method to add @Lazy(false) to it.

With RC1 it’s now possible to apply exclusions programatically by register a LazyInitializationExcludeFilter bean.

For example, to never set IntegrationFlow beans to lazy, you can use the following code:

@Bean
static LazyInitializationExcludeFilter integrationLazyInitExcludeFilter() {
    return LazyInitializationExcludeFilter.forBeanTypes(IntegrationFlow.class);
}

Health Endpoint

Component details returned from /actuator/health can now be configured to be shown independently of the details. The management.endpoint.health.show-components property works in a similar way to show-details and can be set to never, when-authorized or always.

For example, if you want to always show the individal health indicators composed to create the system health, but you don’t want to show their details you can use:

management.endpoint.health.show-components=always
management.endpoint.health.show-details=never

The same property can also be set on a health indicator group.

Dependency Upgrades

Spring Boot 2.2.0.RC1 moves to new versions of several Spring projects:

Numerous third-party dependencies have also been updated, some of the more noteworthy of which are the following:

Jackson 2.10
Lettuce 5.2
Micrometer 1.3
Mockito 3.1

Miscellaneous

Zip64 files are now supported inside "Far Jars".
The ROLLING_FILE_LOG_PATTERN is now exposed for use in logback configurations.
You can now inject and use a customized WebTestClient in any @SpringBootTest.
Dependency management for Oracle’s JDBC driver has been added.
Dependency management for Awaitility has been added.

Deprecations in Spring Boot 2.2.0 RC1

ConfigurationBeanFactoryMetadata in favour of ConfigurationPropertiesBean
ConfigurationPropertiesBindingPostProcessor constructors in favor of @EnableConfigurationProperties or the register method.
ConfigurationPropertiesBindingPostProcessor.VALIDATOR_BEAN_NAME has moved to EnableConfigurationProperties.VALIDATOR_BEAN_NAME
ConfigurationPropertiesBindingPostProcessorRegistrar in favor of @EnableConfigurationProperties
WebTestClientBuilderCustomizer has been relocated to org.springframework.boot.test.web.reactive.server