Any way to serialize date and date-time formats differently in the request body?

[andresmanz]

Our API expects string values with a "date" format (OpenAPI format: date) to be in "YYYY-MM-DD". However, with the date transformer enabled, the client serializes all Date objects as full ISO strings ("YYYY-MM-DDTHH:mm:ss.sssZ"), regardless of whether the schema defines the field as "date" or "date-time".

Is there a clean way to ensure date-formatted fields are serialized as "YYYY-MM-DD" while keeping date-time fields as full ISO strings? I've looked into using a custom bodySerializer, but it lacks access to the request schema/metadata, so I can't distinguish between the two types dynamically.

Am I missing a built-in configuration, or is disabling the date transformer and handling dates manually the recommended path for now?

[mrlubos]

I think this is a bug and there might be a pull request for it too but not sure if there's a linked issue. Are you using Zod or Valibot btw? If yes, possible to use those for transforms? You have more freedom there with custom overrides and behavior

[andresmanz]

Thank you very much, I'll try something with zod. You're right, there's this for example: #3723. Which is for query params only, but could be extended to the body I guess.

And there's this: #3216 But it's been closed.