[kotlin-server] implicitHeaders: Remove header params from API operations

[feczkob]

This PR adds support for "implicit headers" in Kotlin server code generators. When enabled via the implicitHeaders option, header parameters are removed from API method signatures but preserved as Swagger annotations (for Kotlin Spring), allowing frameworks to handle common headers (like authentication tokens) implicitly rather than as explicit method parameters.

Reference PRs for the Java Server implementation:

• [Slim4] Add integration tests #4858
• [Java] implicit headers regex #11819
• Fix spring implicitHeaders w/o annotationLibrary #12921

A future step would be to implement implicitHeadersRegex, if anyone is interested.

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[cubic-dev-ai]

1 issue found across 31 files

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="modules/openapi-generator/src/main/resources/kotlin-server/libraries/jaxrs-spec/apiMethod.mustache">

<violation number="1" location="modules/openapi-generator/src/main/resources/kotlin-server/libraries/jaxrs-spec/apiMethod.mustache:4">
P2: useSwaggerAnnotations support was removed from the kotlin-server jaxrs-spec apiMethod template, so @ApiOperation/@ApiResponses are no longer generated even when the flag is enabled.</violation>
</file>

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

[feczkob]

@karismann (2019/03) @Zomzog (2019/04) @andrewemery (2019/10) @4brunu (2019/11) @yutaka0m (2020/03) @stefankoppier (2022/06) @e5l (2024/10) @dennisameling (2026/02)

Could you take a look, please?

[Picazsoo]

Hello @wing328 , my understanding is that this can be closed as resolved, since this PR took care also of the spring-kotlin codegen.