Do not remove schemas with only a default value form allOf schemas

[WellingR]

A schema with only a default was treated as "meta data only" this caused it to be removed from an allOf schema causing the default value to be lost.

This has been fixed in this MR

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[wing328]

thanks for the PR

can you you please add a test or 2 to the model utils java test file?

[wing328]

cc @ross-paypay

[WellingR]

Sorry for the delay @wing328 , but I have now added a test that reproduced the problem that I had in the inline model resolver tests.

[wing328]

35ba041#diff-b07a3793d0d84981ddc8dc2e080ef2f9c8fa35e4a9063591981d80ab6389455eR424

i think default is just like description, nullable etc which cannot be handled in allOf in inline model resolver at the moment.

[WellingR]

It is true that the inline model resolver does not do anything with this. I have a project which uses a customized generator which accesses the subtypes in allOf. Since #20892 the inline model resolver would remove the subtype that has only a default. I made this change to keep compatibilty and allow extended generators to access this information

[wing328]

can you please share more about your use cases with an example schema? maybe i can come up with a solution

[WellingR]

We have some customizations in a generator as we prefer the use of Optionals. Which is we use updated templates and have some java code to enrich some data in our customized generator.

One specific feature that we added in our custom generator is to merge a default value into a schema, which can specifically be useful for enums.

See the following snippet (which was also added in the test in this MR)

          schema:
            allOf:
              - $ref: '#/components/schemas/MyEnum'
              - default: "One"

Our custom generator output would pretty much add the default value to the enum definition. Perhaps that is a feature that could even be supported in the inline model resolver.

[wing328]

@WellingR i've filed #21342

can you please give it a try to see if it works for your use cases?

[WellingR]

@wing328 Thanks, just built the current version on master locally and this does indeed solve my issue. Than you very much.

Looking forward to the next release.

I will close this MR