Interactions fail to check if DMs are with another user before updating cache

[LJNeon]

Which package is this bug report for?

discord.js

Issue description

1. User A installs Bot to their account.
2. User A runs /command from Bot in their DMs with User B.
3. Bot tries to send a message to User A's DMs (via user.send()).
4. Fails! 50001 Missing Access error because Bot tried to send message to User B's DMs with User A instead of Bot's DMs with User A.

The bot sends reminders and has been struggling with seemingly spontaneous 50001 Missing Access errors for a while now which is causing reminders to have massive delays from the intended reminder date.

Discord thread: https://discord.com/channels/222078108977594368/1474848599857954969

Code sample

Versions

• discord.js 14.25.1
• Node.js 24.14.0

Issue priority

Medium (should be fixed soon)

Which partials do you have configured?

All partials enabled

Which gateway intents are you subscribing to?

No Intents

I have tested this issue on a development release

No response

[imnaiyar]

It's really not the library's job to do these kind of checks, it's you who should be doing it, dm channels have recipientId that you can use the match with invoking user, furthermore you can also restrict the commands context to BotDM or dissallow PrivateChannel

[LJNeon]

To be clear, the library is putting a channel in cache as the bot's DMs that actually doesn't have the bot as a recipient. That causes user.send() to throw a 50001 Missing Access because the bot doesn't actually have access to the channel that is in cache as a DM channel that it is a recipient to. I very strongly disagree with the idea that it's not the library's job to check for this.

[LJNeon]

You would have to modify the library internals to resolve this, which doesn't seem like a reasonable expectation of library users.

[monbrey]

To be clear, the library is putting a channel in cache as the bot's DMs that actually doesn't have the bot as a recipient. That causes user.send() to throw a 50001 Missing Access because the bot doesn't actually have access to the channel that is in cache as a DM channel that it is a recipient to. I very strongly disagree with the idea that it's not the library's job to check for this.

Can I ask you to share a code sample or some more information about how you were able to determine that it's the wrong DM channel?

[imnaiyar]

To be clear, the library is putting a channel in cache as the bot's DMs that actually doesn't have the bot as a recipient. That causes user.send() to throw a 50001 Missing Access because the bot doesn't actually have access to the channel that is in cache as a DM channel that it is a recipient to. I very strongly disagree with the idea that it's not the library's job to check for this.

It's not a bug per-se, many thing in discord.js relies on cache. Ever since user-installable was introduced which made interactions possible in private channels, which was causing interaction to fail due to caching issues even with partials enabled. This was a deliberate choice. As I said, you need to do these checks yourself in your code or set the contexts appropriately

Ok i completely misunderstood the issue, just saw the discord thread. Would have been nice if you had shown a sample code or linked the thread earlier

[Jiralite]

the library is putting a channel in cache as the bot's DMs that actually doesn't have the bot as a recipient

contexts solves this as @imnaiyar said. If that is not what you want your users to do, then you should disallow it.

[Qjuh]

You are right, this is indeed a bug and I found it:

discord.js/packages/discord.js/src/client/actions/InteractionCreate.js

Line 24 in 77e7672

const channel = data.channel && this.getChannel(data.channel);

This calls the following which will wrongly assume the interaction user and the bot are the two recipients in the DMChannel:

discord.js/packages/discord.js/src/client/actions/Action.js

Lines 36 to 39 in 77e7672

	if (!('recipients' in data)) {
	// Try to resolve the recipient, but do not add the client user.
	const recipient = data.author ?? data.user ?? { id: data.user_id };
	if (recipient.id !== this.client.user.id) payloadData.recipients = [recipient];

[vakiliner]

In INTERACTION_CREATE need to check interaction.channel.recipients[0].id === client.user.id, if the condition is true, then interaction.user is the recipient.

[Qjuh]

If that check was applicable the code I linked wouldn't even run. The issue arises from the partial channel data Discord sends which doesn't always contain the recipients field in the first place

[vakiliner]

In INTERACTION_CREATE need to check interaction.channel.recipients[0].id === client.user.id, if the condition is true, then interaction.user is the recipient.

This check needs to be done in the library before caching the channel.

[blubskye]

Possible fix
● Update(packages/discord.js/src/client/actions/Action.js)
⎿  Added 1 line, removed 1 line
36 if (!('recipients' in data)) {
37 // Try to resolve the recipient, but do not add the client user.
38 const recipient = data.author ?? data.user ?? { id: data.user_id };
39 - if (recipient.id !== this.client.user.id) payloadData.recipients = [recipient];
39 + if (recipient.id && recipient.id !== this.client.user.id) payloadData.recipients = [recipient];
40 }
41
42 if (id !== undefined) payloadData.id = id;

● Update(packages/discord.js/src/structures/DMChannel.js)
⎿  Added 7 lines, removed 1 line
32 super._patch(data);
33
34 if (data.recipients) {
35 - const recipient = data.recipients[0];
35 + const clientId = this.client.user?.id;
36 + // If there are multiple recipients and the bot is not among them, this is a DM between
37 + // other users (e.g., a user-installed app interaction from a DM between two users).
38 + // Don't set recipientId to avoid incorrectly caching this as the bot's DM with one of them.
39 + if (clientId && data.recipients.length > 1 && !data.recipients.some(r => r.id === clientId)) return;
40
41 + const recipient = data.recipients.find(r => r.id !== clientId) ?? data.recipients[0];
42 +
43 /**
44 * The recipient's id
45 *