[Go] Fix an issue causing int array reference translated to an invalid type []Integer

[ChihweiLHBird]

CC: @antihax @grokify @kemokemo @jirikuncar @ph4r5h4d @lwj5

Fix an issue causing integer array with items referenced by $ref being generated to an invalid type []Integer.

Sample problematic spce:

openapi: 3.0.3
info:
  version: 1.0.0
  title: My API
  description: |
    some API spec
paths:
  /some-endpoint:
    post:
      servers:
      - url: https://example.com/
      operationId: someOperation
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - ids
              properties:
                MyIntegerArray:
                  type: array
                  items:
                    $ref: '#/components/schemas/ExampleObject/properties/id'

      responses:
        '200':
          description: success
          content:
            application/json:
              schema:
                type: object
components:
  schemas:
    ExampleObject:
      type: object
      properties:
        id:
          readOnly: true
          type: integer

This PR reorder of the if... else if... else... expression to prioritize existing primitive types defined in typeMapping to try to address the issue.

This PR double checks to ensure the openAPIType is in the ref before proceeding to generating a type with the referenced model name to avoid integer type with a reference being converted to Integer, rather than int32.

Further investigation might be needed to look into how ref and get$ref() work because them seems to be null when $ref is '#/components/schemas/SomeID' in the spec, but contains a non-null string value "#/components/schemas/ExampleObject/properties/id" when $ref is the corresponding value. This might be root cause of this issue and may have a larger impact.

Let me know any thoughts, feedback, or idea. Still working on finalizing things with the check list below. Done now.

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[ChihweiLHBird]

CC: @antihax @grokify @kemokemo @jirikuncar @ph4r5h4d @lwj5

[wing328]

thanks for the PR.

can you please add a test in modules/openapi-generator/src/test/resources/3_0/go/petstore-with-fake-endpoints-models-for-testing-with-http-signature.yaml and update the samples?

[ChihweiLHBird]

Hi @wing328, sure! Would it be fine to add a new path in that sample? I feel this fix is hard to be tested in the existing endpoint specifications in that doc.

[wing328]

yes, you can add another fake (tag) endpoint

[wing328]

                $ref: '#/components/schemas/ExampleObject/properties/id'

which version of openapi generator are you using?

I remember adding better support for referencing properties in recent versions (maybe starting in v7.5.0).

[ChihweiLHBird]

Hi @wing328, I was using the master branch, so it should include the changes made in v7.5.0

[ChihweiLHBird]

Hi @wing328, I just added the sample. Does it look good?

[ChihweiLHBird]

Any thought, guys?

[wing328]

from what i understand, this fix only works if the schema name happens to be openAPIType (e.g. string), right?

[ChihweiLHBird]

It has been a while. If I recall correctly (I will double check tomorrow), openAPIType would be a primitive type name, (e.g., "integer"), for a reference to an integer, like this example below.

And openAPIType would be s schema name (e.g., "SomeSchema") for a reference to a schema object.

So, checking whether the ref is ended with the openAPIType can determine whether it's a Schema object, which needs toModelName() to capitalize its first letter, rather than a primitive type, which will be handled elsewhere.

[wing328]

@ChihweiLHBird i've filed #19013 based on this PR.

It fixes the issue differently by checking if the ref is a ref to another schema in a property.

can you please test it to ensure it works for your use cases?

thanks