feat(dto-schema-name): add __schema_name__ to dto base

[Jannchie]

Description

• resolved Bug: Different behavior for generating openapi schema names #3427

I really like this project. I even immediately used it to rewrite my FastAPI-based project.

Especially, it provides DTOs that make it easy to reduce repetitive boilerplate code.

In the current implementation, the DTO generates a Struct for each Response and Request in the backend, which is generally fine. However, this leads to countless repetitive similar definitions in the OpenAPI schema. When I use OpenAPI to generate an SDK, these class names are used for model type definitions, which complicates development due to their differences—unlike with FastAPI, which doesn’t have this issue.

Currently, I find myself unable to specify the __schema_name__ for DTOs, although PydanticDTO has similar functionality.

After reading the source code, it seems not particularly difficult to allow specifying a schema_name. I have added __schema_name__ to the AbstractDTO class and prioritized using this as the model class name.

When generating the schema, it should also allow schemas like classes to be redefined (perhaps it should skip redefinition, but I haven’t figured out how to do that yet.)

In any case, I believe this PR can solve my problem.

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I have already tested the effect in my own project, and it looks good. It introduces almost no complexity; you just need to add a single line for __schema_name__.

class TagDTO(MixedDTO[Tag]):
    __schema_name__ = "TagPublic"
    config = DTOConfig(rename_strategy="camel")

before:

after:

[github-actions]

Documentation preview will be available shortly at https://litestar-org.github.io/litestar-docs-preview/4131