Update API error format on Attester

[DenBond7]

ref #2171 (comment)

FES

{
  "code": 401,
  "message": "Authorization credentials required",
  "details": "io.javalin.http.UnauthorizedResponse"
}

Attester

{
    "error": {
        "message": "Body should not be empty"
    }
}

PubLookup

{
  "code": 404,
  "message": "Not Found",
  "details": ""
}

EKM

{
  "code": 401,
  "message": "Authorization credentials required",
  "details": "io.javalin.http.UnauthorizedResponse: Authorization credentials required"
}

Backend

{
    "error": {
        "code": 400,
        "message": "Wrong request received",
        "internal": "Please add a json body"
    }
}

@tomholub Is it possible to have the same error format for all APIs? it will help to simplify code.

It would be nice to have
(I prefer this one)

{
    "error": {
        "_": ""
        "_": "",
        ...
    }
}

or

{
  "_": "",
  "_": ""
}

[tomholub]

Backend will be removed completely in 3 months

[tomholub]

That leaves Attester to update. can do

[DenBond7]

it looks like we've updated the error format for attester. Now I need to clarify one moment. @tomholub or @martgil Please confirm that error fields(code, message, details) can not be present at the success response(HTTP code 200).

[tomholub]

that's correct

[DenBond7]

@tomholub I have a question. Why do we have different behavior for errors for the following requests?

https://flowcrypt.com/attester/pub/test@test.test

####################################################################################################
https://flowcrypt.com/attester/pub/test

Why do we handle them differently?

[tomholub]

I'm not sure - the 404 is not really an error in this case, it's a result which means "I searched the pubkey successfully, and none was found"

[DenBond7]

Got it. Can we change this behavior? On Android, handling cases with different logic is not simple if we are talking about implementation. IMHO, it will be better to have the same logic over all API if it is possible. To be honest, the best choice will be using JSON even for public key. Like, {"public_key":"..."}. But it seems it's not possible for the particular API.

So the question is - can we return string only for success case, and JSON for other?