How to customize json parsing

[MeikelLP]

My API returns dates as ISO strings. Obviously I don't want to parse it everywhere on the go and thus want to to adjust the parsing of the response.

The default Response.json() method has no overload to adjust the parsing like JSON.parse(string, (key, value) => {}) thus one had to use .text() and parse the result manually. How can I archive this with the openapi-fetch library?

I tried the following:

async onResponse({ response }) {
    const text = await response.text()
    // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
    const json = dateAwareJsonParse(text)
    return Response.json(json, {
        status: response.status,
        statusText: response.statusText,
        headers: response.headers
    })
}

but sadly the static method Response.json() does convert any given object to a string and back thus killing all custom parsing. The library checks the response for a correct Response object via instanceof and thus I can't return a custom object with the correct structure (the code just crashes without any error and the webpage is broken).

How can I customize the response parsing?