Missing 4.0.0 release for spring-boot-starter-undertow

[nick-botticelli]

There is a missing 4.0.0 release for spring-boot-starter-undertow (only appears to be a 4.0.0-M1 version), resulting in a missing dependency error on build when attempting a simple version upgrade to 4.0.0:

Caused by: org.gradle.internal.resolve.ModuleVersionNotFoundException: Could not find org.springframework.boot:spring-boot-starter-undertow:.

Undertow is used via this Gradle dependency snippet:

implementation('org.springframework.boot:spring-boot-starter-web') {
	exclude group:'org.springframework.boot', module:'spring-boot-starter-tomcat'
}
implementation 'org.springframework.boot:spring-boot-starter-undertow'

[anbusampath]

@nick-botticelli Undertow support is dropped - https://github.com/spring-projects/spring-boot/wiki/Spring-Boot-4.0-Migration-Guide#undertow

[rodrigoserracoelho]

Any plans to support again the Undertow starter?

[bclozel]

@rodrigoserracoelho we have no control over how and when undertow will get Servlet 6.1 support and how this new version is maintained. When this happens, we might chose to keep the current arrangement and let developers deploy Spring Boot applications directly on Undertow.