src/lib/server/database.ts

import { MONGODB_URL, MONGODB_DB_NAME, MONGODB_DIRECT_CONNECTION } from "$env/static/private";
import { GridFSBucket, MongoClient } from "mongodb";
import type { Conversation } from "$lib/types/Conversation";
import type { SharedConversation } from "$lib/types/SharedConversation";
import type { AbortedGeneration } from "$lib/types/AbortedGeneration";
import type { Settings } from "$lib/types/Settings";
import type { User } from "$lib/types/User";
import type { MessageEvent } from "$lib/types/MessageEvent";
import type { Session } from "$lib/types/Session";

if (!MONGODB_URL) {
	throw new Error(
		"Please specify the MONGODB_URL environment variable inside .env.local. Set it to mongodb://localhost:27017 if you are running MongoDB locally, or to a MongoDB Atlas free instance for example."
	);
}

const client = new MongoClient(MONGODB_URL, {
	directConnection: MONGODB_DIRECT_CONNECTION === "true",
});

export const connectPromise = client.connect().catch(console.error);

const db = client.db(MONGODB_DB_NAME + (import.meta.env.MODE === "test" ? "-test" : ""));

const conversations = db.collection<Conversation>("conversations");
const sharedConversations = db.collection<SharedConversation>("sharedConversations");
const abortedGenerations = db.collection<AbortedGeneration>("abortedGenerations");
const settings = db.collection<Settings>("settings");
const users = db.collection<User>("users");
const sessions = db.collection<Session>("sessions");
const messageEvents = db.collection<MessageEvent>("messageEvents");
const bucket = new GridFSBucket(db, { bucketName: "files" });

export { client, db };
export const collections = {
	conversations,
	sharedConversations,
	abortedGenerations,
	settings,
	users,
	sessions,
	messageEvents,
	bucket,
};

client.on("open", () => {
	conversations
		.createIndex(
			{ sessionId: 1, updatedAt: -1 },
			{ partialFilterExpression: { sessionId: { $exists: true } } }
		)
		.catch(console.error);
	conversations
		.createIndex(
			{ userId: 1, updatedAt: -1 },
			{ partialFilterExpression: { userId: { $exists: true } } }
		)
		.catch(console.error);
	abortedGenerations.createIndex({ updatedAt: 1 }, { expireAfterSeconds: 30 }).catch(console.error);
	abortedGenerations.createIndex({ conversationId: 1 }, { unique: true }).catch(console.error);
	sharedConversations.createIndex({ hash: 1 }, { unique: true }).catch(console.error);
	settings.createIndex({ sessionId: 1 }, { unique: true, sparse: true }).catch(console.error);
	settings.createIndex({ userId: 1 }, { unique: true, sparse: true }).catch(console.error);
	users.createIndex({ hfUserId: 1 }, { unique: true }).catch(console.error);
	users.createIndex({ sessionId: 1 }, { unique: true, sparse: true }).catch(console.error);
	messageEvents.createIndex({ createdAt: 1 }, { expireAfterSeconds: 60 }).catch(console.error);
	sessions.createIndex({ expiresAt: 1 }, { expireAfterSeconds: 0 }).catch(console.error);
	sessions.createIndex({ sessionId: 1 }, { unique: true }).catch(console.error);
});