feature(jackson3) add jackson3 support for spring generator by antechrestos · Pull Request #22854 · OpenAPITools/openapi-generator

antechrestos · 2026-01-30T17:01:47Z

Description

This pull request aim to provide jackson 3 support for spring generator. as it is the recommanded way for any springboot 4 project (see #22294 )

add 'useJackson3' option

I added this option only at the spring generator level, so as not to make it visible for all java generators (as I caught sight of it when a I generated the documentation).

This option sets the variable jacksonPackage so as to ease template migration:

when useJackson3 is clear, jacksonPackage is valued to com.fasterxml.jackson
when useJackson3 is set, jacksonPackage is valued to tools.jackson

I added tests for SpringCodegen in order to test that the jackson 3 import is well added.

This option is only available alongside with useSpringBoot4 and without openApiNullable as this late one brings a jackson 2 module.

add support for RestClient in spring-http-interfaces

The client for spring http interface should use RestClient instead of WebClient in non reactive mode; the WebClient is the reactive implementation of spring clients. As RestClient was added in spring 6.1 / spring boot 3.2, I updated the pom-sb3 dependencies to 3.2.0. Also updated spring cloud to 2023.0.0 for compability with spring boot 3.2 (see compatibility matrix). Clubic AI complains about requirement pushed to jdk 17 but springboot 3 already requires jdk 17.

add 'useSpringBoot4' option

I willingly introduced this option in order to limitate, for spring generator, the use of jackson 3 only when using a spring boot 4 project. This option allows to build a springboot 4 pom.xml as dependencies change in springboot 4.

PR checklist

built locally
re generated samples
regenerated documentation (java camel server inherits from spring
test on a personnal project in spring boot 4

Summary by cubic

Adds Jackson 3 support to the Spring generator, updates non-reactive spring-http-interface clients to RestClient, and adds Spring Boot 4 templates with updated docs, tests, and samples.

New Features
- New options: useJackson3 and useSpringBoot4; sets jacksonPackage=tools.jackson for templates.
- Templates switch Jackson 2/3 imports across models, YAML/XML, RFC3339DateFormat, and application props; fixed JsonDeserialize import.
- Non-reactive spring-http-interface now uses RestClient + RestClientAdapter and starter-web; reactive stays on WebClient/webflux; READMEs updated to Spring Framework 6.1.
- New SB4 POMs for spring-boot, spring-cloud, and spring-http-interface; added SB4 config files and samples (spring-cloud-4-with-optional, spring-http-interface-springboot-4); SB3 baselines bumped to Spring Boot 3.3.13 and Java 17; tests added to validate option constraints; docs updated to include useJackson3 in Spring and Java Camel pages.
Migration
- To use Jackson 3, set useSpringBoot4=true and useJackson3=true; do not enable SB3 and SB4 together.
- useJackson3 is incompatible with openApiNullable.
- For non-reactive spring-http-interface clients, provide a RestClient bean; reactive clients are unchanged.

^{Written for commit 3310ee7. Summary will update on new commits.}

cubic-dev-ai

15 issues found across 87 files

Note: This PR contains a large number of files. cubic only reviews up to 75 files per PR, so some files may not have been reviewed.

Prompt for AI agents (all issues)


Check if these issues are valid — if so, understand the root cause of each and fix them.


<file name="samples/client/petstore/spring-http-interface-noResponseEntity-jackson-3/README.md">

<violation number="1" location="samples/client/petstore/spring-http-interface-noResponseEntity-jackson-3/README.md:17">
P2: README example passes a WebClient to HttpInterfacesAbstractConfigurator, but the generated configurator expects a RestClient, so the example will not compile.</violation>
</file>

<file name="samples/client/petstore/spring-http-interface-noResponseEntity-jackson-3/src/main/java/org/openapitools/api/FakeApi.java">

<violation number="1" location="samples/client/petstore/spring-http-interface-noResponseEntity-jackson-3/src/main/java/org/openapitools/api/FakeApi.java:213">
P2: MultipartFile parameter is declared with @RequestPart, but the request content type is set to application/x-www-form-urlencoded. File uploads in Spring use multipart/form-data, so this mismatch prevents sending the binary part correctly and can lead to 415/empty file data.</violation>
</file>

<file name="modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-cloud/pom-sb3.mustache">

<violation number="1" location="modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-cloud/pom-sb3.mustache:134">
P2: Jackson 3 dependencies are added without a managed version; when useJackson3 is enabled the generated POM lacks a version or BOM for tools.jackson.*, which will cause Maven build failures.</violation>
</file>

<file name="modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-http-interface/httpInterfacesConfiguration.mustache">

<violation number="1" location="modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-http-interface/httpInterfacesConfiguration.mustache:41">
P2: Non-reactive template now requires RestClient (Spring 6.1+), breaking generated code for Spring Boot 3.0/3.1 users without a fallback or version guard.</violation>
</file>

<file name="CONTRIBUTING.md">

<violation number="1" location="CONTRIBUTING.md:15">
P3: Introduced typo in contribution guideline text (“staonrt a discussi”), which should remain “start a discussion.”</violation>
</file>

<file name="modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-http-interface/pom4.mustache">

<violation number="1" location="modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-http-interface/pom4.mustache:98">
P2: `jackson-databind-nullable` is a Jackson 2 module (`com.fasterxml.jackson`) but is always added even when `useJackson3` is enabled, which uses `tools.jackson` artifacts. This mixes incompatible Jackson versions and prevents registering the nullable module with a Jackson 3 `ObjectMapper`.</violation>
</file>

<file name="modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-http-interface/pom.mustache">

<violation number="1" location="modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-http-interface/pom.mustache:58">
P2: The template enables servlet (`spring-boot-starter-web`) when `reactive=false`, but generated code uses `RestClient`, which was introduced in Spring Framework 6.1 (Boot 3.2+). The default parent remains Spring Boot 3.1.3 (Spring 6.0), so non-reactive generated projects will fail to compile due to missing `RestClient`.</violation>
</file>

<file name="samples/client/petstore/spring-http-interface-noResponseEntity-jackson-3/src/main/java/org/openapitools/api/StoreApi.java">

<violation number="1" location="samples/client/petstore/spring-http-interface-noResponseEntity-jackson-3/src/main/java/org/openapitools/api/StoreApi.java:39">
P2: `orderId` uses `String` for DELETE but `Long` for GET on the same `{order_id}` path variable, creating an inconsistent API contract for the same endpoint and conflicting with the Javadoc’s integer ID expectation.</violation>
</file>

<file name="modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-boot/pom-sb4.mustache">

<violation number="1" location="modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-boot/pom-sb4.mustache:234">
P2: jackson-databind-nullable 0.2.8 is a Jackson 2 module but is always added even in useJackson3 mode, leading to Jackson 2/3 API incompatibility when registering JsonNullableModule.</violation>
</file>

<file name="samples/client/petstore/spring-http-interface-noResponseEntity-jackson-3/pom.xml">

<violation number="1" location="samples/client/petstore/spring-http-interface-noResponseEntity-jackson-3/pom.xml:63">
P1: Missing version for tools.jackson.datatype:jackson-datatype-jsr310; without dependencyManagement this will fail Maven resolution.</violation>

<violation number="2" location="samples/client/petstore/spring-http-interface-noResponseEntity-jackson-3/pom.xml:67">
P2: jackson-databind-nullable 0.2.8 is a Jackson 2 module (com.fasterxml.jackson.*) and will not integrate with Jackson 3 (tools.jackson.*) ObjectMapper used by this jackson-3 sample, causing incompatible dependencies.</violation>
</file>

<file name="modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-boot/pom-sb3.mustache">

<violation number="1" location="modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-boot/pom-sb3.mustache:184">
P2: Jackson 3 (`tools.jackson.*`) dependencies are added without versions; Spring Boot 3.1.3 only manages `com.fasterxml.jackson.*`, so `useJackson3` builds will fail to resolve these artifacts unless versions/BOM are added.</violation>
</file>

<file name="modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-boot/pom.mustache">

<violation number="1" location="modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-boot/pom.mustache:198">
P3: Unreachable mustache block: this dependency is wrapped in {{^useJackson3}}, so the inner {{#useJackson3}} groupId section can never render. This dead code is confusing and likely a logic oversight.</violation>

<violation number="2" location="modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-boot/pom.mustache:199">
P2: Jackson 3 dependencies are added without versions, but Spring Boot 2.7.x parent does not manage tools.jackson.* artifacts. Projects generated with useJackson3 will fail Maven resolution with missing version errors.</violation>

<violation number="3" location="modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-boot/pom.mustache:288">
P2: When `useJackson3` is enabled, the template switches core Jackson dependencies to `tools.jackson.*` but still includes `jackson-databind-nullable` 0.2.8 (a Jackson 2 `com.fasterxml.jackson` module). This creates an incompatible dependency mix and will fail when trying to register the JsonNullable module with a Jackson 3 ObjectMapper.</violation>
</file>

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samples/client/petstore/spring-http-interface-noResponseEntity-jackson-3/pom.xml

samples/client/petstore/spring-http-interface-noResponseEntity-jackson-3/README.md

...ng-http-interface-noResponseEntity-jackson-3/src/main/java/org/openapitools/api/FakeApi.java

modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-cloud/pom-sb3.mustache

...in/resources/JavaSpring/libraries/spring-http-interface/httpInterfacesConfiguration.mustache

modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-boot/pom-sb3.mustache

modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-boot/pom.mustache

CONTRIBUTING.md

modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-boot/pom.mustache

Picazsoo · 2026-01-30T17:43:37Z

I wonder what use the HttpInterfacesAbstractConfigurator has in practice. I would expect majority of the developers to write their own configuration class such as:

@Configuration
class ApiClientConfig {

    @Bean
    PetApi petApi(WebClient webClient) {
        return HttpServiceProxyFactory
            .builder(WebClientAdapter.forClient(webClient))
            .build()
            .createClient(PetApi.class);
    }
}

I mean - the point of the declarative interface is that it should be client-agnostic. So one can grab it and instantiate their own client with it regardless whether they use WebClient, RestClient or RestTemplate...

In my opinion it just makes maintenance of this generator much more costly than it needs to be for a very little benefit.

And it is not flexible enough. Often one wants to use a different WebClient/RestClient per interface. And this generated one does not seem to offer that.

antechrestos · 2026-01-30T21:16:47Z

@Picazsoo I juste adapted the existing code and did not want to bring toomuch change in this, quite already, big change 😅

In my case I only generates interface and model, and generates client in my code with interceptors, url and so on...

Picazsoo · 2026-01-30T22:03:17Z

Yes, I understand you are simply working with the current state and bringing it up to date. No problem with that (-: !

antechrestos · 2026-02-02T09:04:13Z

@cubic-dev-ai rerun a review

cubic-dev-ai · 2026-02-02T09:04:31Z

@cubic-dev-ai rerun a review

@antechrestos I have started the AI code review. It will take a few minutes to complete.

cubic-dev-ai

10 issues found across 35 files

Prompt for AI agents (all issues)


Check if these issues are valid — if so, understand the root cause of each and fix them.


<file name="modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-http-interface/README.mustache">

<violation number="1" location="modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-http-interface/README.mustache:12">
P3: Mustache conditional is malformed in README template, producing duplicated/mismatched client names (e.g., `WebClientWebClientRestClient`) and incorrect client type for non-reactive mode. Use complementary reactive/non-reactive blocks.</violation>
</file>

<file name="samples/openapi3/client/petstore/spring-cloud-3-with-optional/pom.xml">

<violation number="1" location="samples/openapi3/client/petstore/spring-cloud-3-with-optional/pom.xml:17">
P2: Spring Boot 3.2.x requires Java 17+, but the project still targets Java 8, causing incompatibility after upgrading the parent to 3.2.0.</violation>
</file>

<file name="samples/client/petstore/spring-http-interface-noResponseEntity/README.md">

<violation number="1" location="samples/client/petstore/spring-http-interface-noResponseEntity/README.md:17">
P3: Documentation says to provide a WebClient while the updated example uses RestClient, creating a mismatch about the required client type.</violation>
</file>

<file name="samples/client/petstore/spring-http-interface/README.md">

<violation number="1" location="samples/client/petstore/spring-http-interface/README.md:17">
P3: README text still instructs providing a WebClient while the example constructor now uses RestClient, leaving the documentation inconsistent.</violation>
</file>

<file name="samples/client/petstore/spring-http-interface-reactive-noResponseEntity/README.md">

<violation number="1" location="samples/client/petstore/spring-http-interface-reactive-noResponseEntity/README.md:12">
P2: README now refers to malformed client class `WebClientWebClientRestClient` instead of the correct `WebClient` for the reactive sample.</violation>
</file>

<file name="samples/client/petstore/spring-http-interface-reactive/README.md">

<violation number="1" location="samples/client/petstore/spring-http-interface-reactive/README.md:12">
P3: README now refers to a malformed/non-existent class name `WebClientWebClientRestClient`; it should reference `WebClient` to match the actual constructor usage.</violation>
</file>

<file name="modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-cloud/pom-sb3.mustache">

<violation number="1" location="modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-cloud/pom-sb3.mustache:38">
P2: Spring Boot 3.2.0 manages Spring Security 6.2.x; keeping spring-security-oauth2-client pinned to 6.1.1 will mix Spring Security versions on the classpath. Drop the explicit version (or update to the BOM-managed version) to stay compatible with the new parent.</violation>
</file>

<file name="modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-boot/pom-sb4.mustache">

<violation number="1" location="modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-boot/pom-sb4.mustache:231">
P1: Jackson 2-only jackson-databind-nullable is included even when useJackson3 is enabled, mixing incompatible Jackson major versions.</violation>
</file>

<file name="modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-http-interface/pom-sb4.mustache">

<violation number="1" location="modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-http-interface/pom-sb4.mustache:95">
P2: When useJackson3 is enabled, the template still adds jackson-databind-nullable 0.2.8, which depends on Jackson 2 (`com.fasterxml.jackson`). Jackson 3 changes packages to `tools.jackson`, so this module is incompatible and will fail to register or compile in Jackson 3 mode. Consider conditionally excluding or using a Jackson 3-compatible nullable module when useJackson3 is true.</violation>
</file>

<file name="modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-boot/openapi2SpringBoot.mustache">

<violation number="1" location="modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-boot/openapi2SpringBoot.mustache:34">
P2: jsonNullableModule returns a Jackson 2 Module instance while the signature expects Jackson 3 JacksonModule under useJackson3, causing a type mismatch and compilation failure.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}

modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-boot/pom-sb4.mustache

samples/openapi3/client/petstore/spring-cloud-3-with-optional/pom.xml

samples/client/petstore/spring-http-interface-reactive-noResponseEntity/README.md

modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-cloud/pom-sb3.mustache

...api-generator/src/main/resources/JavaSpring/libraries/spring-http-interface/pom-sb4.mustache

...pi-generator/src/main/resources/JavaSpring/libraries/spring-boot/openapi2SpringBoot.mustache

...napi-generator/src/main/resources/JavaSpring/libraries/spring-http-interface/README.mustache

samples/client/petstore/spring-http-interface-noResponseEntity/README.md

samples/client/petstore/spring-http-interface/README.md

samples/client/petstore/spring-http-interface-reactive/README.md

antechrestos · 2026-02-02T12:44:03Z

@cubic-dev-ai rerun a review

cubic-dev-ai · 2026-02-02T12:44:21Z

@cubic-dev-ai rerun a review

@antechrestos I have started the AI code review. It will take a few minutes to complete.

cubic-dev-ai

3 issues found across 35 files

Prompt for AI agents (all issues)


Check if these issues are valid — if so, understand the root cause of each and fix them.


<file name="samples/openapi3/client/petstore/spring-cloud-3/pom.xml">

<violation number="1" location="samples/openapi3/client/petstore/spring-cloud-3/pom.xml:18">
P2: Spring Boot 3.2 requires Java 17+, but this POM still targets Java 8, which is incompatible with the updated parent version and its dependencies.</violation>
</file>

<file name="samples/openapi3/client/petstore/spring-cloud-3-with-optional/pom.xml">

<violation number="1" location="samples/openapi3/client/petstore/spring-cloud-3-with-optional/pom.xml:17">
P2: Upgrading to Spring Boot 3.2.0 requires Java 17+, but the POM still targets Java 8 via java.version, causing an incompatible build/runtime configuration. Update the Java version to 17+ to match Spring Boot 3.2.</violation>
</file>

<file name="modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-http-interface/pom.mustache">

<violation number="1" location="modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-http-interface/pom.mustache:78">
P2: When useJackson3 is enabled, the POM adds tools.jackson.* dependencies without any version or BOM. Since this POM has no dependencyManagement and spring-boot-starter-parent only manages com.fasterxml.jackson artifacts, Maven will fail with “version missing” for these Jackson 3 dependencies.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}

samples/openapi3/client/petstore/spring-cloud-3/pom.xml

samples/openapi3/client/petstore/spring-cloud-3-with-optional/pom.xml

...openapi-generator/src/main/resources/JavaSpring/libraries/spring-http-interface/pom.mustache

antechrestos · 2026-02-02T13:28:51Z

@cubic-dev-ai rerun a review

cubic-dev-ai · 2026-02-02T13:29:07Z

@cubic-dev-ai rerun a review

@antechrestos I have started the AI code review. It will take a few minutes to complete.

cubic-dev-ai

2 issues found across 35 files

Prompt for AI agents (all issues)


Check if these issues are valid — if so, understand the root cause of each and fix them.


<file name="modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-boot/openapi2SpringBoot.mustache">

<violation number="1" location="modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-boot/openapi2SpringBoot.mustache:5">
P3: `useJackson3` adds a `JacksonModule` import but no code uses it because the jsonNullableModule bean is only generated for `{{^useJackson3}}`. This produces unused imports in generated code when `openApiNullable` and `useJackson3` are both enabled.</violation>
</file>

<file name="samples/client/petstore/spring-http-interface/README.md">

<violation number="1" location="samples/client/petstore/spring-http-interface/README.md:12">
P2: README now requires Spring’s RestClient but still links to Spring Framework 6.0.0 docs, which predate RestClient. Update the reference link to a 6.1+ version to avoid misleading users.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}

samples/client/petstore/spring-http-interface/README.md

...pi-generator/src/main/resources/JavaSpring/libraries/spring-boot/openapi2SpringBoot.mustache

antechrestos · 2026-02-02T14:13:55Z

@cubic-dev-ai rerun a review

cubic-dev-ai · 2026-02-02T14:14:11Z

@cubic-dev-ai rerun a review

@antechrestos I have started the AI code review. It will take a few minutes to complete.

cubic-dev-ai

1 issue found across 35 files

Prompt for AI agents (all issues)


Check if these issues are valid — if so, understand the root cause of each and fix them.


<file name="modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/SpringCodegen.java">

<violation number="1" location="modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/SpringCodegen.java:499">
P2: useJackson3 only remaps JsonDeserialize; JsonProperty/JsonValue/JsonCreator still map to com.fasterxml, causing mixed Jackson 2/3 annotations in generated models when useJackson3 is enabled.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/SpringCodegen.java

wing328 · 2026-02-03T09:56:54Z

thanks for the PR

cc @cachescrubber (2022/02) @welshm (2022/02) @MelleD (2022/02) @atextor (2022/02) @manedev79 (2022/02) @javisst (2022/02) @borsch (2022/02) @banlevente (2022/02) @Zomzog (2022/09) @martin-mfg (2023/08) to review

wing328 · 2026-02-03T10:12:50Z

docs/generators/java-camel.md

 |useEnumCaseInsensitive|Use `equalsIgnoreCase` when String for enum comparison| |false|
 |useFeignClientContextId|Whether to generate Feign client with contextId parameter.| |true|
 |useFeignClientUrl|Whether to generate Feign client with url parameter.| |true|
+|useJackson3|Set it in order to use jackson 3 dependencies (only allowed when `useSpringBoot4` is set and incompatible with `openApiNullable`).| |false|


when useSpringBoot4 is enabled, does it mean it use Jackson 2.x by default?

@wing328 you raise a good point. I did not correlate them (despite the compatibility); yet I think that using spring boot 4 should enable jackson 3 by default as it is the default behaviour in spring boot.

What do you think? For developer experience this would lower the number of parameter given to the generator by default.

I think this is misleading. The Jackson 3 settings should not be tied to a Spring Boot 4 setting. The Java generator with the resttemplate library also uses Jackson 2 and should support Jackson 3.

@ML-Marco in order not to impact too much files, I wanted to only address the spring generator.
In spring, only springboot 4 supports Jackson 3,there is no use supporting it in other spring boot version

@ML-Marco so as you suggest I do not add a correlated behavior between two parameters

Ah ok I see what you mean; I was puzzled on this question. As you read, springboot strongly advise to move to jackson 3 and tells jackson 2 won't be supported in the future. Yet it is supported. For now.
So I though: is this the responsibility of a tool to take this decision? Shall it be removed when springboot does not support jackson 2 anymore?

Could the jackson2 vs 3 be handled in a similar way as are the {{javax}} imports? (meaning - the value of {{javax}} is programatically subtituted to represent either jakarta or javax)

That could lead to a minimal code change across the project and maybe more maintainable template files going forward?

@Picazsoo that's a great idea; I will take a look at it in spring generator and give you a feedback

As @Picazsoo smartly spotted, introducing a template variable jacksonPackage valued to either com.fasterxml.jackson when useJackson3 is clear, or valued to tools.jackson when useJackson3 is set really ease templating.

Some use of useJackson3 remains

for open api module dependency

for jsr310 module dependency

for any use of jakson Module (renamed to JacksonModule in jackson3)

For almost every other needs, setting the variable to com.fasterxml.jackson or tools.jackson allows to both solve dependency declaration and imports. This will ease a lot other templates migration.

I've just updated PR description

antechrestos · 2026-02-09T10:53:23Z

@wing328 thank you.

In the meantime, do you wish me to rebase my work despite no conflict are detected?

antechrestos · 2026-02-13T08:17:11Z

@wing328 any news? I can provide you if you need an openapi yaml that illustrates the case where the library inserts jackson databind packages

wing328 · 2026-02-13T11:11:56Z

sorry too busy these days, will get it tested soon and make sure it's included in the upcoming release due this weekend or next monday

antechrestos · 2026-02-13T11:28:08Z

@wing328 tell me whether I may help you.

I would like to push after the fix pointed by @jpfinne which is quite light yet impact tons of generated samples.

wing328 · 2026-02-13T16:31:03Z

I did a test with java -jar modules/openapi-generator-cli/target/openapi-generator-cli.jar generate -g spring -i modules/openapi-generator/src/test/resources/3_0/petstore.yaml -o /tmp/sp3/ --additional-properties useSpringBoot4=true,useJackson3=true,openApiNullable=false but the output won't compile:

[INFO]
[INFO] Results:
[INFO]
[ERROR] Errors:
[ERROR]   OpenApiGeneratorApplicationTests.contextLoads ? IllegalState Failed to load ApplicationContext for [WebMergedContextConfiguration@646427f7 testClass = org.openapitools.OpenApiGeneratorApplicationTests, locations = [], classes = [org.openapitools.OpenApiGeneratorApplication], contextInitializerClasses = [], activeProfiles = [], propertySourceDescriptors = [], propertySourceProperties = ["org.springframework.boot.test.context.SpringBootTestContextBootstrapper=true"], contextCustomizers = [org.springframework.boot.test.context.PropertyMappingContextCustomizer@0, org.springframework.boot.test.context.filter.ExcludeFilterContextCustomizer@7e38a7fe, org.springframework.boot.test.json.DuplicateJsonObjectContextCustomizerFactory$DuplicateJsonObjectContextCustomizer@1c80e49b, org.springframework.boot.test.autoconfigure.OnFailureConditionReportContextCustomizerFactory$OnFailureConditionReportContextCustomizer@1252b961, org.springframework.test.context.support.DynamicPropertiesContextCustomizer@0, org.springframework.boot.webmvc.test.autoconfigure.WebDriverContextCustomizer@5ddabb18, org.springframework.boot.web.server.context.SpringBootTestRandomPortContextCustomizerFactory$Customizer@50eca7c6, org.springframework.boot.test.context.SpringBootTestAnnotation@af3a5fb8], resourceBasePath = "src/main/webapp", contextLoader = org.springframework.boot.test.context.SpringBootContextLoader, parent = null]
[INFO]
[ERROR] Tests run: 1, Failures: 0, Errors: 1, Skipped: 0
[INFO]
[INFO] ------------------------------------------------------------------------

Does it work for you in your environment?

antechrestos · 2026-02-13T17:15:51Z

@wing328 I tested it on a project of mine.
I take a look at it by tomorrow

Are you using Java 17 at least, just to be sure?

wing328 · 2026-02-13T17:19:58Z

Yes, I'm using JDK17

antechrestos · 2026-02-13T19:16:22Z

@wing328 I've spotted the issue: it was a property that was moved in springboot 4

The issue you add was encountered due to bad configuration.

I've retested in local and tests passed.

I've fixed it and also rebased my work

Picazsoo · 2026-02-13T19:31:18Z

Shouldn't this functionality be tested by a generated sample included for a compilation check? My understanding is that would catch the issue that @wing328 discovered and you subsequently fixed?

The compile checks are really good for preventing regressions.

antechrestos · 2026-02-13T20:14:37Z

@Picazsoo it was not a compilation but a runtime issue due to bad configuration for spring server .

I thought that the numerous tests compiled and built running generated test but I think it would be too much consumption.

Picazsoo · 2026-02-13T20:25:21Z

The compilation tests actually also test spring startup as the ci/cd pielines run the tests. You can check many of the .yaml file in the config directory.

I usually try to look for some existing config and adapt it to cover multiple functionalities in one go.

But maybe this still would not catch the issue you had?

antechrestos · 2026-02-14T11:58:25Z

@Picazsoo What I tried to emphasize was that it was due to configuration that was produced and not bad code; the code compiled hence valid (which means that if you only use the code it is ok) yet it would not be ok if you directly published it as a library without modifying configuration.

I have just added three samples and their generation.

a sample for spring boot
a sample for spring cloud (which illustrate the fact that spring-cloud-starter-parent is no more released ; I did not change pom-sb3.xml as this PR would get unreadable
a sample for http-interface

This brings the following changes

@wing328 tell me if you prefer I make a revert on adding the samples so as to lower the number of files or either the rebase , or the squashes.

🙏

wing328 · 2026-02-14T14:03:51Z

bin/configs/spring-boot-4.yaml

@@ -0,0 +1,17 @@
+generatorName: spring
+outputDir: samples/openapi3/server/petstore/springboot-4


please add the new folders to https://github.com/OpenAPITools/openapi-generator/blob/master/.github/workflows/samples-spring-jdk17.yaml so that CI will test it moving forward

@wing328 I added them yet it is not launched... Shouldn't add it to samples-jdk17.yaml instead? As I see them launched with different synthax (/** for instance)

or maybe does it takes main branch specification instead? 🤔

I see that I also added samples/client/petstore/spring-http-interface but it was present in samples-jdk17.yaml, I shall remove it and keep only the v4 version

* add 'useJackson3' option * add 'useSpringBoot4' option * add support for RestClient in spring-http-interfaces * add 'jacksonPackage' template variable set from useJackson3 option See OpenAPITools#22294

wing328 · 2026-02-15T06:26:26Z

all tests passed

let's give it a try

thanks for the contribution

antechrestos · 2026-02-15T13:54:08Z

@wing328 do not hesitate to tag me on eventual issues, I will gladly contribute on maintenance

wing328 · 2026-02-15T14:05:03Z

@antechrestos thank you for offering help to maintain it moving forward.

…ools#22854) * add 'useJackson3' option * add 'useSpringBoot4' option * add support for RestClient in spring-http-interfaces * add 'jacksonPackage' template variable set from useJackson3 option See OpenAPITools#22294

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feature(jackson3) add jackson3 support for spring generator

3310ee7

* add 'useJackson3' option * add 'useSpringBoot4' option * add support for RestClient in spring-http-interfaces * add 'jacksonPackage' template variable set from useJackson3 option See OpenAPITools#22294

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wing328 merged commit 5a70edb into OpenAPITools:master Feb 15, 2026
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antechrestos deleted the features/add-suppport-for-useJackson3-option-for-spring-generator branch February 15, 2026 09:26

antechrestos mentioned this pull request Feb 15, 2026

fixes(spring) add JsonProperty on setter #22978

Open

faltfe mentioned this pull request Feb 16, 2026

[BUG][SPRING] Deprecated MappingJackson2HttpMessageConverter for RestClient generator #22985

Open

6 tasks

		@@ -0,0 +1,17 @@
		generatorName: spring
		outputDir: samples/openapi3/server/petstore/springboot-4

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Description

add 'useJackson3' option

add support for RestClient in spring-http-interfaces

add 'useSpringBoot4' option

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