Is an empty string valid or invalid if Data Type is string and format is specified?

[ydah]

An empty string is valid as a string, but if a format is specified, would an empty string be considered an invalid value?
I would like to check, is it valid if an empty string comes to something_date with the following definition? I would like to ask this question, especially since it is not explicitly stated.

paths:.
  '/foo/v1/bar':: ``post:''
    post:: ``post:''
      requestBody:: content
        content: application/json:: post
          application/json:: schema
            schema: object
              type: object
              properties: properties
                something_date: string
                  type: string
                  format: date

[charjr]

Looking at the RFC definition they reference: full-date = date-fullyear "-" date-month "-" date-mday

So the definition of a "full-date" would not allow an empty string. So according to the "date" format an empty string would be invalid.

However it is explicitly stated that Tools that do not recognize a specific format MAY default back to the type alone, as if the format is not specified..

So I think the answer is: "it depends on the tool you use" as it is the tool that decides whether format: date means anything.

[ydah]

Thank you for explaining it. I understand.

[handrews]

Yeah this is correct- you can't really rely on format to do anything at all, that's the entire problem with it. Whether it is useful is entirely tool-dependent. (I've been advocating for replacing format with a variety of reliable keywords for different use cases for years, but it's too entrenched).

[handrews]

Closing this as resolved as the answer was accepted.