Describe the problem

I'm making a full-stack website in SvelteKit, and am now working on my API. This api is located under /api/*. When a user requests from an unknown URI I want to send a 404 message. As the API responds with json, I would like to respond in the same manner with the error message. However, to my knowledge, __error.svelte files only support html as an output.

Describe the proposed solution

I can see two solutions

1. implementation of an __error.json file
2. an export in endpoints that get executed on all undefined http methods

I prefer number 2, as then I could also implement 405 Method Not Allowed errors.

Alternatives considered

For now, I'm using an endpoint like this:

function response() { return {
    status: 404,
    body: {
        "error": "notfound",
        "message": "Not Found"
    }
}}

// Most HTTP request methods
export const get = response;
export const post = response;
export const put = response;
export const patch = response;
export const del = response;
export const options = response;
export const head = response;

this is located under src/routes/api/[...error].ts

Although this works, it's pretty ugly imo and it doesn't cover all infinite custom http methods clients could be using.

Importance

nice to have

Additional Information

No response