Can the information about parameter verification failure in the interface be customized?

[YueXiaWyl]

from litestar import Litestar, get


@get(path="/test")
    async def test(
        self,
        authors_repo: AuthorRepository,
        name: str = Parameter(
            title="测试",
            max_length=5,
            description="这是一个测试名称字段name",
        ),
    ) -> dict[str, str]:
        """Test."""
        print(authors_repo.statement)
        return {"test": name}


app = Litestar(route_handlers=[test])

The above is a test code. When the string passed in the current segment is greater than 5, the verification fails. The failure message is not user-friendly. Is there any way to customize it and return a user-friendly prompt message? In China, I will return a "user name length cannot exceed 5 characters" or “用户名称不能超过5个字符串”

You can change the message field in the screenshot above to a custom message.

[euri10]

I dont think it's possible to customize to that level since what you get in the extra/message comes from msgspec under the hood (someone may correct me on this Im not 100% sure),
However maybe you can achieve something close to what you desire with the excepton handling: https://docs.litestar.dev/latest/usage/exceptions.html

[FHU-yezi]

You can use custom exception handler to achive this:

app = Litestar(
    exception_handlers=[...],  # your exception handler
)

Notice that once you use this option, the defaul exception handlers (404, 405 etc.) and unknown exception handler will no longer be available :( , so you should manually process them, like this:

# imports omitted

def not_found_exception_handler(_: Request, __: NotFoundException) -> Response:
    return Response(b"", status_code=HTTP_404_NOT_FOUND)

def method_not_allowed_exception_handler(
    _: Request, __: MethodNotAllowedException
) -> Response:
    return Response(b"", status_code=HTTP_405_METHOD_NOT_ALLOWED)

def unknown_exception_handler(request: Request, exception: Exception) -> Response:
    ...  # your customized logic

EXCEPTION_HANDLERS: ExceptionHandlersMap = {
    NotFoundException: not_found_exception_handler,
    MethodNotAllowedException: method_not_allowed_exception_handler,
    Exception: unknown_exception_handler,
}

And then, add ValidationException: validation_exception_handler to EXCEPTION_HANDLERS, and in this function do what you want:

def validation_exception_handler(
    request: Request, exception: ValidationException
) -> Response:
    ...  # your customized logic