Random misleading Unknown Interaction errors

[ImRodry]

Description

I've seen this issue reported by many people but so far no one has been able to gather enough information to reliably explain what's going on. An example can be seen at discordjs/discord.js#7005
In summary, every now and then at a seemingly random chance it's possible that a bot's reply to an interaction fails due to an Unknown Interaction when, in reality, the reply succeeded and was shown to the user (by reply I mean a regular reply, deferred reply or update). I know this because I've been investigating this issue on a bot I manage for around a week now and I asked some users who were impacted by this.
In the following screenshots I'm logging the time it took for me to reply by subtracting the current timestamp to the interaction's created_timestamp, and then logging the time it took for the bot to receive the error by subtracting the timestamp at the time the error was received to the one before the request was submitted. You can see that the reply is sent pretty fast and in time for Discord to accept it, however, the error comes 5 seconds later, indicating some sort of issue on Discord's end.

And of course I could be faking those numbers but it would make no sense for me to do that so I'm gonna have to ask you to trust that.
I later asked the user impacted by this issue to see what the bot responded with, and they showed that the reply was indeed deferred, which means that that error was a false positive and everything worked fine on our end.

Steps to Reproduce

There are no steps to consistently reproduce this issue as it only happens randomly. What I can tell is that the error comes when the API takes too long to send the response back but actually acknowledges and processes it.

Expected Behavior

The reply is sent correctly (happening) and a success message is returned

Current Behavior

The reply is sent correctly but an "Unknown Interaction" error is thrown

Screenshots/Videos

Can only attach what I've shown above already


(Bot is thinking but in Portuguese)

Client and System Information

discord.js v14.6.0 on Node v18.11.0 running on Debian 11 (bullseye)

[DV8FromTheWorld]

Can you provide a code snippet showing how these logs were generated?
I'm curious as to whether it is all coming from one request or possibly retries. There are a number of interacting systems here, so additional information to help debug the issue would be beneficial.

[ImRodry]

afaik discord.js only retries to submit requests when getting a 429 response which I assume not to be the case here on freshly created interactions, so there are no retries being done here to my knowledge

This is the first line that gets executed in the entire event that isn't an if statement and nothing above it interacts with the API other than this line. Hope this helps

[ImRodry]

Keep in mind this issue can happen with other kinds of interaction replies, not only deferred messages (I tested with showing a modal). I only showed that snippet because it's the most basic one that should never generate that error

[ImRodry]

Hey @DV8FromTheWorld do you have any updates on this?

[ooliver1]

I have been getting this too, we check if it has been 3 seconds and it definitely has not at the time of request, but sometimes get this response.
nextcord@2.2.0

[kenyonbowers]

Yeah, I have been getting this error as well. And I haven't changed my code since updating Discord.js to v14.6.0.

[DV8FromTheWorld]

I have not looked deeper into this issue at this time. This is the first time I've heard of this issue.
Before assuming it is a problem with Discord I would likely investigate the underlying library implementation.

For debugging purposes: Is there a way in your library (or tech stack) to track outbound network traffic? If there is, it would be useful to indicating whether the library is re-attempting a network call or if the initial network call is actually taking 5 seconds. From your code snippet that isn't possible to determine.

[ImRodry]

I’m not sure if there is but I can dig into the source code and add that myself. I do, however, doubt that is the case, as we’ve seen @ooliver1 say they are experiencing the same behavior and they’re using a python library, which is completely different from the one I’m using

[ooliver1]

It's pretty hard to reproduce confidently, since it's been random a lot of the time

[kenyonbowers]

I have found that letting it sit running for multiple hours after starting the bot allows it to not have that error until you turn the bot off and try to run it again without letting it sit.