springdoc-openapi v3.0.0 compatability

[star-fangled-nut]

Hi, is springdoc-openapi v3.0.0 compatible with Spring Boot 3 or is this only intended to be used with Spring Boot 4?

It's a bit unclear to me so hoping someone can advise.

[dbelyaev]

Just want to add: the team released version v3.0.0, but there was no mention of compatibility, and the README file still says that it supports Spring Boot v3 here:

springdoc-openapi/README.md

Lines 77 to 80 in 60a1704

	This library supports:
	* OpenAPI 3
	* Spring-boot v3 (Java 17 & Jakarta EE 9)

However, it obviously gives users an exception due to some missing classes (for example, when trying to start a project with Spring Boot v3.5.8 and springdoc-openapi-starter-webmvc-ui v3.0.0):

java.lang.NoClassDefFoundError: org/springframework/boot/web/context/servlet/ApplicationServletEnvironment

When I take a look at the dependencies in springdoc-openapi-starter-webmvc-ui v3.0.0, you can quickly see that it now depends on Spring Boot v4 libraries, which possibly causes the issue.

It looks like v3.0.0 does not work so well with Spring Boot v3.x.x as some classes it depends on has been moved in Spring Boot v4.

But it is me speculating, until it is confirmed by dev team.

[dbelyaev]

@bnasslahsen can you, please, add some information or references to this discussion?

[dbelyaev]

@star-fangled-nut

Oh I see there is an additional text paragraph:

springdoc-openapi/README.md

Lines 90 to 91 in 60a1704

	For *spring-boot v3* support, make sure you
	use [springdoc-openapi v2](https://springdoc.org/)

So, I assume it is not compatible, only version v2.x.x should be used with Spring Boot v3.

But documentation should be more transparent on this.

Currently it has one liner for the Spring Boot v2 and v1 support at the start of the document:

springdoc-openapi/README.md

Lines 7 to 8 in 60a1704

	IMPORTANT: ``springdoc-openapi v1.8.0`` is the latest Open Source release supporting
	Spring Boot 2.x and 1.x.

Then it says that it is generally support Spring Boot v3 in the main section:

springdoc-openapi/README.md

Lines 77 to 80 in 60a1704

	This library supports:
	* OpenAPI 3
	* Spring-boot v3 (Java 17 & Jakarta EE 9)

And in the third place a little below it adds that Spring Boot v3 is only supported by versions v2.x.x:

springdoc-openapi/README.md

Lines 90 to 91 in 60a1704

	For *spring-boot v3* support, make sure you
	use [springdoc-openapi v2](https://springdoc.org/)

[star-fangled-nut]

Thanks, this makes sense. I should have looked closer at the docs. I'll avoid using v3 in projects that haven't yet been updated to Spring Boot 4.