Spring Boot 2.2.0 M3 Release Notes

For changes in earlier milestones, please refer to:

Upgrading from Spring Boot 2.1

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

Spring Framework 5.2

This release upgrades to Spring Framework 5.2 M2. Please refer to Spring Framework’s upgrade documentation for further details.

Actuator HTTP Trace and Auditing are disabled by default

The Actuator HTTP Trace and Auditing features are not enabled by default anymore, since the default repositories implementations are in-memory and may consume too many resources and are not cluster friendly. For robust, production-grade HTTP tracing we recommend the use of Spring Cloud Sleuth or similar.

To enable HTTP tracing, contribute a bean implementing HttpTraceRepository or AuditEventRepository to turn those features back on. Configuration properties are available to turn those features off even in the presence of beans (see management.auditevents.enabled and management.trace.http.enabled)

Gradle requirements

The minimum requirements for Gradle have changed - Spring Boot now requires Gradle 4.10+. Please upgrade accordingly.

Jetty logging configuration

As of #16416, server.jetty.accesslog. configuration properties related to log formatting are no longer available (the ones related to log files are still there).

If your application is making use of those properties, two new keys have been introduced, format and custom-format; format allows you to choose amongst existing formats, custom-format allows you to use your own format:

server.jetty.accesslog.format=NCSA # enum with predefined formats: NCSA, EXTENDED_NCSA
server.jetty.accesslog.custom-format= # String, custom format overriding the former if defined

Unsupported options now translate to defining a custom log format and using options as defined in Jetty’s CustomRequestLog.

New and Noteworthy

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

RSocket improvements

Following the new RSocket features introduced in M2, this release adds auto-configuration for RSocketRequester.Builder components, allowing you to send requests to remote RSocket services (see reference docs). Jackson CBOR is also now the codec of choice for encoding/decoding binary payloads efficiently.