Refactor to make it more like the Android app

web/src/app/ConnectionManager.js

@@ -0,0 +1,36 @@
+import Connection from "./Connection";
+
+export class ConnectionManager {
+    constructor() {
+        this.connections = new Map();
+    }
+
+    refresh(subscriptions, onNotification) {
+        console.log(`[ConnectionManager] Refreshing connections`);
+        const subscriptionIds = subscriptions.ids();
+        const deletedIds = Array.from(this.connections.keys()).filter(id => !subscriptionIds.includes(id));
+
+        // Create and add new connections
+        subscriptions.forEach((id, subscription) => {
+            const added = !this.connections.get(id)
+            if (added) {
+                const wsUrl = subscription.wsUrl();
+                const connection = new Connection(wsUrl, id, onNotification);
+                this.connections.set(id, connection);
+                console.log(`[ConnectionManager] Starting new connection ${id} using URL ${wsUrl}`);
+                connection.start();
+            }
+        });
+
+        // Delete old connections
+        deletedIds.forEach(id => {
+            console.log(`[ConnectionManager] Closing connection ${id}`);
+            const connection = this.connections.get(id);
+            this.connections.delete(id);
+            connection.cancel();
+        });
+    }
+}
+
+const connectionManager = new ConnectionManager();
+export default connectionManager;