502 error handling

[shrayus-masanam]

The Discord API can sometimes return status code 502. According to their docs, you just have to "wait a bit and retry" your request (https://discord.com/developers/docs/topics/opcodes-and-status-codes).

This can be problematic when there isn't proper error handling because file uploads can be interrupted and will never complete. Waiting an arbitrary amount of time (like 10 seconds) and then retrying the request should fix this.

Additionally, if one or more requests return status code 429, line 102 (throw new Error(...);) will ALWAYS run after all recursive calls to this.fetchFromApi finish. This means that errors will populate the console even if the upload succeeded with rate limits. I'm not sure if this is intentional, but I changed the conditional to an else if block just in case. Changes are welcomed

[DisboxApp]

The wait seconds should probably be in a const.

[DisboxApp]

Hey!
Thank you so much for the PR :)

This sounds like a good idea, but I have a few questions:

First, about the change from if to else if in line 102 - are you sure that's what you're experiencing? The code is something like this:

if (429)
    return ...
if (>400)
   raise ...

If the status is 429 - the function should return there and never reach the next line. So it shouldn't matter if it's if or else if.

My second question is about the change itself. Is this something you've actually experienced and tested this fixes? It sounds like you're right from the API docs, but we try to reproduce this and see your solution fixes it.

[shrayus-masanam]

Hey there, my mistake, I misinterpreted the return behavior of the function. if/else if should both work as you said.

As for the 502 change, I haven't been able to reproduce it since it originally happened to me, but I have tested by changing the fetch function:

const realFetch = fetch;
let return502 = true;
fetch = async function() {
    let response = await realFetch(...arguments);
    if (return502 && typeof arguments[0] === "string" && arguments[0].includes("discordapp.com")) {
        console.log("hijacking");
        return502 = false;
        return { // returns a fake 502 response object for the first request
            status: 502,
            headers: response.headers,
            body: null,
            async text() {
                return "whatever it returns"
            }
        }
    }
    return response;
}

This works with the changes that I made, but what I'm noticing now is that in my original screenshot, the error originated from line 84, which is the fetch function call. So I think some additional changes would have to be made to the fetch call to handle the error, maybe something like this:

const response = await fetch(`${this.baseUrl}${path}`, {
    method: method,
    body: body,
}).catch(e => {}); // catching errors

Although what I'm not sure about is why fetch threw an error. Fetch shouldn't reject on HTTP errors: https://developer.mozilla.org/en-US/docs/Web/API/fetch

[SpaceSaver]

Although what I'm not sure about is why fetch threw an error. Fetch shouldn't reject on HTTP errors: https://developer.mozilla.org/en-US/docs/Web/API/fetch

Bet it doesn't in FF
Edit: I couldn't get Chrome or Firefox to reject on an HTTP error. Both log an error to console though.