AI SDK client side id generation creates out of sync frontend state

[Andrew-Chen-Wang]

The example repository (see here

ai-sdk-persistence-db/app/api/chat/route.ts

Line 24 in 1c2f43d

await upsertMessage({ chatId, id: message.id, message });

) seems to accept the client side ID of the user written message which doesn't seem safe.

My assumption is that in the example repository, you could rewrite the submitted message ID to your own ID, but then your frontend would be out of sync -- I assume that's fine though. What doesn't make sense is, if you generate the ID for the user ID and send it back as per the doc (

ai-sdk-persistence-db/app/api/chat/route.ts

Lines 34 to 40 in 1c2f43d

	writer.write({
	type: "start",
	messageId: generateId(),
	});
	writer.write({
	type: "start-step",
	});

), then the frontend state is out of sync.

Please advise @nicoalbanese