[BUG] [Spring] [Java] Invalid code generated for schemas with oneOf object attributes

[wagnerrobsan]

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator (example)?
• Have you tested with the latest master to confirm the issue still exists?
• Have you searched for related issues/PRs?
• What's the actual output vs expected output?
• [Optional] Sponsorship to speed up the bug fix or feature request (example)

Description

When generating a spring or java code with a spec that contains an attribute with oneOf, the code generator creates a code with a bug

Spec: https://gist.github.com/wagnerrobsan/88d81d113d4add401667e64ab814e3aa

Creates the following java code:

public Fruit putBodyItem(String key,  bodyItem) {
    if (this.body == null) {
      this.body = ;
    }
    this.body.put(key, bodyItem);
    return this;
  }

openapi-generator version

latest version, build from master

OpenAPI declaration file content or url

Providing minimal reproducing example (YAML):

Spec: https://gist.github.com/wagnerrobsan/88d81d113d4add401667e64ab814e3aa

Generation Details

see Steps to reproduce for more details

Steps to reproduce

git clone https://github.com/openapitools/openapi-generator
cd openapi-generator
mvn clean package
java -jar modules/openapi-generator-cli/target/openapi-generator-cli.jar generate \
-i https://gist.githubusercontent.com/wagnerrobsan/88d81d113d4add401667e64ab814e3aa/raw/ab969d651c60e76be6b44ba69950c77b9992c108/openapi-oneOfbug.yaml \
-g spring \
-o /outputFolder/oneOfBugApiClient

Related issues/PRs

Related to

• [Feature][Java/Spring] Support Discriminator Based OneOf Interface #11650
• [BUG] [spring][server] oneOf Polymorphism support for spring boot #5381

Suggest a fix

The code generator should skip in the mustache file the putBodyItem method creation.
see file JavaSpring/pojo.mustache

[wing328]

Please try the latest master (snapshot version can be found in the readme) as there's a merged PR related to Spring's oneOf support.

[wagnerrobsan]

Please try the latest master (snapshot version can be found in the readme) as there's a merged PR related to Spring's oneOf support.

Hi William,
I'm building the code from master, actually I found it when I was testing the feature #11650 used to fix the bug. Take a look steps to reproduce
The java generator thinks it's a Map Schema and tries to create putItem method

  {{#isMap}}
  public {{classname}} put{{nameInCamelCase}}Item(String key, {{{items.datatypeWithEnum}}} {{name}}Item) {
    {{^required}}
    if (this.{{name}} == null) {
      this.{{name}} = {{{defaultValue}}};
    }
    {{/required}}
    this.{{name}}.put(key, {{name}}Item);
    return this;
  }
  {{/isMap}}

Thanks

[wagnerrobsan]

Hi @wing328
I fixed the bug (added a unit test, a yaml file and a small change to the DefaultCodegen class), but I'm getting 403 trying to push the new branch.
Can you please advise? If you want I can share more details about the patch here,
Thanks

[cachescrubber]

@wagnerrobsan This is not a Bug. Inline definition of oneOf is currently not supported You have to model an explicit FruitBody Schema.

  fruit:
    title: fruit
    additionalProperties: false
    properties:
      fruitId:
        type: string
        description: The unique ID of the fruit
      body:
        $ref: '#/components/schemas/FruitBody'
  FruitBody:
    type: object
    description: The raw event payload that will be different based on the event.
    discriminator:
      propertyName: kind
    oneOf:
      - $ref: '#/components/schemas/apple'
      - $ref: '#/components/schemas/banana'

The following spec should do the trick: https://gist.github.com/cachescrubber/f77ebc1d6f1b7f0e20aa593dde469ad2.

[wagnerrobsan]

Hi @cachescrubber
Thanks for your quick response and propose the alternative solution , appreciate it!

I created a Pull Request to support oneOf inline usage. I hope it makes sense, it's not a big change and it implements/fix the inline oneOf support
#11987
Thanks

[wing328]

Please give the latest master another try as we've improved inline schema handling and oneOf support in Spring generator.

Happy to reopen if this is still an issue.