add channel communication

websocket-handler.ts

@@ -0,0 +1,42 @@
+// TYPES
+// requests
+interface IncomingMessage {
+  //sent on new connections
+  connectionType?: ConnectionType;
+
+  // subscribing to channel
+  channelSubscription?: string;
+
+  //sending message
+  messageChannel?: string;
+  messageBody?: string;
+}
+
+// connections
+enum ConnectionType {
+  Server = "server",
+  Client = "client",
+}
+
+// TRACKING
+const serversOnEntireNetwork = new Set<WebSocket>();
+
+const socketsPerChannel = new Map<string, Set<WebSocket>>();
+const channelsPerSocket = new Map<WebSocket, Set<string>>();
+
+export function trackServer(ws: WebSocket): void {
+  serversOnEntireNetwork.add(ws);
+}
+
+export function trackSubscription(channel: string, ws: WebSocket): void {
+  if (!socketsPerChannel.has(channel)) socketsPerChannel.set(channel, new Set());
+  if (!channelsPerSocket.has(ws)) channelsPerSocket.set(ws, new Set());
+
+  socketsPerChannel.get(channel)!.add(ws);
+  channelsPerSocket.get(ws)!.add(channel);
+}
+
+export function forgetConnection(ws: WebSocket): void {
+  serversOnEntireNetwork.delete(ws);
+  serversOnEntireNetwork.delete(ws);
+}