Upgrade Guide 3.0

Upgrading from Zuul 2

Zuul 3 has a similar underlying platform as Zuul 2, however we are removed support for a number of platforms.

Key changes:

• javax has been replaced with jakarta
• zuul-groovy & groovy filter support has been removed
• zuul-guice has been removed
• JDK v21+ support only
• Numerous removal of unused code and tidying up via static analysis

javax to jakarta

javax has been replaced within zuul with jakarta equivalents. This should be mostly a transparent change, however if you are relying on javax being supplied by zuul in your project, you should update references to use jakarta:

javax.inject:javax.inject:1
to
jakarta.inject:jakarta.inject-api:2.0.1

zuul-groovy and groovy filter support

The dynamic loading of groovy filters is no longer supported. You should migrate to using Java compiled filters instead. zuul-sample now ships with Java equivalent filters.

zuul-guice

Guice module is no longer provided. We recommend using spring-boot as a dependency injection framework.

JDK v21 support

We now only test and verify zuul against JDK v21.