Add a cleanup mechanism for old db entries

flottform/forms/src/flottform-channel-host.ts

@@ -11,6 +11,9 @@ import {
 
 export class FlottformChannelHost extends EventEmitter<FlottformEventMap> {
 	private flottformApi: string | URL;
+	private baseApi: string;
+	private endpointId: string = '';
+	private hostKey: string = '';
 	private createClientUrl: (params: { endpointId: string }) => Promise<string>;
 	private rtcConfiguration: RTCConfiguration;
 	private pollTimeForIceInMs: number;
@@ -35,6 +38,11 @@ export class FlottformChannelHost extends EventEmitter<FlottformEventMap> {
 	}) {
 		super();
 		this.flottformApi = flottformApi;
+		this.baseApi = (
+			this.flottformApi instanceof URL ? this.flottformApi : new URL(this.flottformApi)
+		)
+			.toString()
+			.replace(/\/$/, '');
 		this.createClientUrl = createClientUrl;
 		this.rtcConfiguration = DEFAULT_WEBRTC_CONFIG;
 		this.pollTimeForIceInMs = pollTimeForIceInMs;
@@ -55,14 +63,9 @@ export class FlottformChannelHost extends EventEmitter<FlottformEventMap> {
 		if (this.openPeerConnection) {
 			this.close();
 		}
-		const baseApi = (
-			this.flottformApi instanceof URL ? this.flottformApi : new URL(this.flottformApi)
-		)
-			.toString()
-			.replace(/\/$/, '');
 
 		try {
-			this.rtcConfiguration.iceServers = await this.fetchIceServers(baseApi);
+			this.rtcConfiguration.iceServers = await this.fetchIceServers(this.baseApi);
 		} catch (error) {
 			// Use the default configuration as a fallback
 			this.logger.error(error);
@@ -74,11 +77,13 @@ export class FlottformChannelHost extends EventEmitter<FlottformEventMap> {
 		const session = await this.openPeerConnection.createOffer();
 		await this.openPeerConnection.setLocalDescription(session);
 
-		const { endpointId, hostKey } = await this.createEndpoint(baseApi, session);
+		const { endpointId, hostKey } = await this.createEndpoint(this.baseApi, session);
+		this.hostKey = hostKey;
+		this.endpointId = endpointId;
 		this.logger.log('Created endpoint', { endpointId, hostKey });
 
-		const getEndpointInfoUrl = `${baseApi}/${endpointId}`;
-		const putHostInfoUrl = `${baseApi}/${endpointId}/host`;
+		const getEndpointInfoUrl = `${this.baseApi}/${endpointId}`;
+		const putHostInfoUrl = `${this.baseApi}/${endpointId}/host`;
 
 		const hostIceCandidates = new Set<RTCIceCandidateInit>();
 		await this.putHostInfo(putHostInfoUrl, hostKey, hostIceCandidates, session);
@@ -103,6 +108,8 @@ export class FlottformChannelHost extends EventEmitter<FlottformEventMap> {
 			this.openPeerConnection = null;
 		}
 		this.changeState('disconnected');
+		// Cleanup old entries.
+		this.deleteEndpoint(this.baseApi, this.endpointId, this.hostKey);
 	};
 
 	private setupDataChannelListener = () => {
@@ -223,6 +230,19 @@ export class FlottformChannelHost extends EventEmitter<FlottformEventMap> {
 		return response.json();
 	};
 
+	private deleteEndpoint = async (baseApi: string, endpointId: string, hostKey: string) => {
+		const response = await fetch(`${baseApi}/${endpointId}`, {
+			method: 'DELETE',
+			headers: {
+				Accept: 'application/json',
+				'Content-Type': 'application/json'
+			},
+			body: JSON.stringify({ hostKey })
+		});
+
+		return response.json();
+	};
+
 	private fetchIceServers = async (baseApi: string) => {
 		const response = await fetch(`${baseApi}/ice-server-credentials`, {
 			method: 'GET',

flottform/forms/src/flottform-text-input-host.ts

@@ -67,6 +67,7 @@ export class FlottformTextInputHost extends BaseInputHost<Listeners> {
 		this.emit('receive');
 		// We suppose that the data received is small enough to be all included in 1 message
 		this.emit('done', e.data);
+		this.close();
 	};
 
 	private registerListeners = () => {

flottform/server/src/database.ts

@@ -13,6 +13,7 @@ type EndpointInfo = {
 		session: RTCSessionDescriptionInit;
 		iceCandidates: RTCIceCandidateInit[];
 	};
+	lastUpdate: number;
 };
 type SafeEndpointInfo = Omit<EndpointInfo, 'hostKey' | 'clientKey'>;
 
@@ -25,8 +26,40 @@ function createRandomEndpointId(): string {
 
 class FlottformDatabase {
 	private map = new Map<EndpointId, EndpointInfo>();
+	private cleanupIntervalId: NodeJS.Timeout | null = null;
+	private cleanupPeriod = 30 * 60 * 1000; // (30 minutes)
+	private entryTTL = 25 * 60 * 1000; // Time-to-Live for each entry (25 minutes)
 
-	constructor() {}
+	constructor() {
+		this.startCleanup();
+	}
+
+	private startCleanup() {
+		this.cleanupIntervalId = setInterval(() => {
+			// Loop over all entries and delete the stale ones.
+			const now = Date.now();
+			for (const [endpointId, endpointInfo] of this.map) {
+				const lastUpdated = endpointInfo.lastUpdate;
+				if (now - lastUpdated > this.entryTTL) {
+					this.map.delete(endpointId);
+					console.log(`Cleaned up stale entry: ${endpointId}`);
+				}
+			}
+		}, this.cleanupPeriod);
+	}
+
+	private stopCleanup() {
+		// Clear the interval to stop cleanup
+		if (this.cleanupIntervalId) {
+			clearInterval(this.cleanupIntervalId);
+			this.cleanupIntervalId = null;
+		}
+	}
+
+	// Stop the cleanup when the database is no longer needed
+	destroy() {
+		this.stopCleanup();
+	}
 
 	async createEndpoint({ session }: { session: RTCSessionDescriptionInit }): Promise<EndpointInfo> {
 		const entry = {
@@ -35,7 +68,8 @@ class FlottformDatabase {
 			hostInfo: {
 				session,
 				iceCandidates: []
-			}
+			},
+			lastUpdate: Date.now()
 		};
 		this.map.set(entry.endpointId, entry);
 		return entry;
@@ -46,6 +80,7 @@ class FlottformDatabase {
 		if (!entry) {
 			throw Error('Endpoint not found');
 		}
+		entry.lastUpdate = Date.now();
 		const { hostKey: _ignore1, clientKey: _ignore2, ...endpoint } = entry;
 
 		return endpoint;
@@ -72,7 +107,8 @@ class FlottformDatabase {
 
 		const newInfo = {
 			...existingSession,
-			hostInfo: { ...existingSession.hostInfo, session, iceCandidates }
+			hostInfo: { ...existingSession.hostInfo, session, iceCandidates },
+			lastUpdate: Date.now()
 		};
 		this.map.set(endpointId, newInfo);
 
@@ -105,7 +141,8 @@ class FlottformDatabase {
 		const newInfo = {
 			...existingSession,
 			clientKey,
-			clientInfo: { session, iceCandidates }
+			clientInfo: { session, iceCandidates },
+			lastUpdate: Date.now()
 		};
 		this.map.set(endpointId, newInfo);