Spring Boot 4.1.0 M2 Release Notes

Spring Boot 4.1.0-M2 Release Notes

Upgrading from Spring Boot 4.0

New and Noteworthy

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

Specify the Encoding When Importing Configuration Files

When spring.config.import is used, it’s now possible to specify the encoding. In the past, property files always have been loaded with the ISO-8859-1 encoding (which is still the default). To load them using a different encoding, you can use this syntax:

spring.config.import=classpath:import.properties[encoding=utf-8]

Info Endpoint

The info endpoint now provides additional information about the process. The following fields are now available in the endpoint’s response:

process.uptime
process.startTime
process.currentTime
process.timezone
process.locale
process.workingDirectory

Refer to the endpoint’s API documentation for further details.

Service Connections to RabbitMQ Streams

Service connections to RabbitMQ Streams are now supported with both Testcontainers and Docker Compose.

When using Testcontainers, a service connection can be made using @ServiceConnection(type = RabbitStreamConnectionDetails.class). The rabbitmq_stream plugin must also be enabled in the container as shown in the following example:

private static RabbitMQContainer createRabbitMqStreamContainer() {
	RabbitMQContainer container = TestImage.container(RabbitMQContainer.class);
	container.addExposedPorts(RABBITMQ_STREAMS_PORT);
	String enabledPlugins = "[rabbitmq_stream].";
	container.withCopyToContainer(Transferable.of(enabledPlugins), "/etc/rabbitmq/enabled_plugins");
	return container;
}

When using Docker Compose, the RabbitMQ service must map container port 5552. As with Testcontainers, the rabbitmq_stream plugin must also be enabled as shown in the following example:

services:
  rabbitmq:
    image: '{imageName}'
    environment:
      - 'RABBITMQ_DEFAULT_USER=myuser'
      - 'RABBITMQ_DEFAULT_PASS=secret'
    configs:
      - source: plugins
        target: /etc/rabbitmq/enabled_plugins
    ports:
      - '5552'
configs:
  plugins:
    content: "[rabbitmq_stream]."

Dependency Upgrades

Spring Boot 4.0.0-M2 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:

Miscellaneous

Apart from the changes listed above, there have also been lots of minor tweaks and improvements including:

Customizers for OtlpHttpLogRecordExporterBuilder and OtlpGrpcLogRecordExporterBuilder have been added.
Additional mime types that should be compressed when sending HTTP responses can be configured using server.compression.additional-mime-types
Kotlin extensions for TestEntityManager have been added.
The actuator info endpoint now returns certificates from the truststore, too.
Value objects now bind Optional parameters as Optional.empty() rather than null. This applies to any @ConfigurationProperties that use constructor binding.
Compression can now be used when exporting metrics over OTLP. To enable compression set management.otlp.metrics.export.compression-mode to gzip.