[BUG] [Groovy] Fix client to work with services that support other formats in addition to JSON

[sekikn]

This PR fixes the Groovy client to add the Accept header since it only supports JSON wire format as of now.
It also includes some fixes for the sample tests, because the current client implementation doesn't seem to deal with the enum conversion and the redirect from http to https correctly.

You can ensure its behavior as follows:

Build openapi-generator and generate the Groovy sample with JDK 11+:

$ ./mvnw clean install
$ bin/generate-samples.sh bin/configs/groovy.yaml

Run the sample tests against the generated client with JDK 8:

$ cd samples/client/petstore/groovy
$ gradle wrapper
$ ./gradlew clean build --info

(snip)

openapitools.PetApiTest > testGetPetByStatus STANDARD_OUT
    url=https://petstore.swagger.io uriPath=/v2/pet/findByStatus

openapitools.PetApiTest > testGetPetByStatus STANDARD_ERROR
    SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
    SLF4J: Defaulting to no-operation (NOP) logger implementation
    SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.

openapitools.PetApiTest > testUpdateOnePet STANDARD_OUT
    url=https://petstore.swagger.io uriPath=/v2/pet
    url=https://petstore.swagger.io uriPath=/v2/pet/10009
    url=https://petstore.swagger.io uriPath=/v2/pet/10009
    url=https://petstore.swagger.io uriPath=/v2/pet/10009
    url=https://petstore.swagger.io uriPath=/v2/pet/10009
    url=https://petstore.swagger.io uriPath=/v2/pet/10009

openapitools.PetApiTest > testAddAndGetPet STANDARD_OUT
    url=https://petstore.swagger.io uriPath=/v2/pet
    url=https://petstore.swagger.io uriPath=/v2/pet/10009

Gradle Test Executor 6 finished executing tests.

(snip)

BUILD SUCCESSFUL in 4s
5 actionable tasks: 5 executed

PR checklist

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  fixes [BUG] [Groovy] Generated client can't work with the openapi-petstore service by default #22907
• If your PR is targeting a particular programming language, @mention the technical committee members, so they are more likely to review the pull request.
  No one is in the Groovy technical committee as of now, so let me ping @wing328

---

Summary by cubic

Set the Accept header per operation using each operation’s produces list (preferring application/json), and add JAXB-based XML request/response support so Groovy clients work with servers that offer JSON or XML. Fixes #22907.

• New Features

  • XML support end-to-end: JAXB annotations in models and XML encode/decode in the client when the spec declares XML.

• Bug Fixes

  • Use operation produces to set Accept via selectHeaderAccept and generator templates; prefer application/json when available.
  • Preserve enum names (enumPropertyNaming: original) and update Pet/Order enums and tests to use typed enums.
  • Switch sample base URLs to https to avoid http→https redirects.
  • Add a Groovy-specific petstore.yaml and point groovy.yaml inputSpec to it.

^{Written for commit 9bd583a. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 10 files

[wing328]

thanks for the PR

according to the description. the change should support other formats in addition to JSON but looks like it's now hard-code to application/json.

should it use the accept provided in the spec instead?

[sekikn]

Thank you so much for reviewing @wing328.

according to the description. the change should support other formats in addition to JSON but looks like it's now hard-code to application/json.

My intention was to force the server to respond in JSON format by specifying that header in the request, because all of the servers listed in the official document at least support JSON.
But yes, it is clear that adding new format support is better as you mentioned, since there can be a service only supporting XML in the wild. Let me give it a try.

should it use the accept provided in the spec instead?

Agreed, I'll fix it accordingly.

[cubic-dev-ai]

1 issue found across 3 files (changes from recent commits).

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/Groovy/modelEnum.mustache">

<violation number="1" location="modules/openapi-generator/src/main/resources/Groovy/modelEnum.mustache:12">
P2: @XmlEnumValue expects a String literal, but boolean enums render @XmlEnumValue(true) without quotes, which will not compile in XML-enabled generation.</violation>
</file>

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

[cubic-dev-ai]

2 issues found across 4 files (changes from recent commits).

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/groovy/src/main/groovy/org/openapitools/api/ApiUtils.groovy">

<violation number="1" location="samples/client/petstore/groovy/src/main/groovy/org/openapitools/api/ApiUtils.groovy:75">
P2: Recursive array parsing still calls the old 3-argument parse signature, which will throw MissingMethodException after the method signature was expanded to include `response`. Array responses will fail to deserialize.</violation>
</file>

<file name="modules/openapi-generator/src/main/resources/Groovy/ApiUtils.mustache">

<violation number="1" location="modules/openapi-generator/src/main/resources/Groovy/ApiUtils.mustache:101">
P2: XML parsing short-circuits array handling; XML responses for array operations will return a single instance instead of a collection.</violation>
</file>

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