separation of concerns

src/index.ts

@@ -1,43 +1,19 @@
+import { WebSocketHandler } from './utils/websocket.js';
 export class TetherClient {
-    private ws: WebSocket | null = null;
+    private websocketHandler: WebSocketHandler = new WebSocketHandler();
     private subscribedQueries = new Map<string, (data: any) => void>();
 
     connect = (url: string) => {
-        this.ws = new WebSocket(url);
-        this.ws.onopen = () => {
-            console.log('Connected to Tether');
-        };
-        this.ws.onmessage = (event) => {
-            const data = JSON.parse(event.data);
-            if (data.type === 'query') {
-                this.subscribedQueries.forEach((callback, query) => {
-                    if (data.query === query) {
-                        callback(data.data);
-                    }
-                });
-            } else if (data.type === 'error') {
-                console.error(data.error);
-            }
-        };
-        this.ws.onclose = () => {
-            console.log('Disconnected from Tether');
-        };
+        this.websocketHandler.startConnection(url);
     };
     
     disconnect = () => {
-        if (!this.ws || this.ws.readyState !== WebSocket.OPEN) {
-            throw new Error('Not connected to Tether');
-        }
-        this.ws.close();
-        this.ws = null;
+        this.websocketHandler.close();
     };
     
     subscribe = (query: string, callback: (data: any) => void) => {
         this.subscribedQueries.set(query, callback);
-        if (!this.ws || this.ws.readyState !== WebSocket.OPEN) {
-            throw new Error('Not connected to Tether');
-        }
-        this.ws.send(JSON.stringify({
+        this.websocketHandler.send(JSON.stringify({
             type: 'subscribe',
             query: query
         }));
@@ -45,20 +21,14 @@ export class TetherClient {
     
     unsubscribe = (query: string) => {
         this.subscribedQueries.delete(query);
-        if (!this.ws || this.ws.readyState !== WebSocket.OPEN) {
-            throw new Error('Not connected to Tether');
-        }
-        this.ws.send(JSON.stringify({
+        this.websocketHandler.send(JSON.stringify({
             type: 'unsubscribe',
             query: query
         }));
     };
     
     sendMutation = (mutationName: string, params: any) => {
-        if (!this.ws || this.ws.readyState !== WebSocket.OPEN) {
-            throw new Error('Not connected to Tether');
-        }
-        this.ws.send(JSON.stringify({
+        this.websocketHandler.send(JSON.stringify({
             type: 'mutation',
             name: mutationName,
             payload: params,

src/utils/websocket.ts

@@ -0,0 +1,75 @@
+export class WebSocketHandler {
+    private ws: WebSocket | null = null;
+    private url: string = '';
+    private subscribedQueries = new Map<string, (data: any) => void>();
+    private onOpen: () => void = () => {};
+    private onClose: () => void = () => {};
+    private reconnectAttempts: number = 0;
+    private maxReconnectAttempts: number = 5;
+    private reconnectInterval: number = 1000;
+    private sendQueue: string[] = [];
+
+    startConnection = (url: string) => {
+        this.url = url;
+        this.ws = new WebSocket(url);
+        const ws = this.ws;
+
+        ws.onopen = () => {
+            console.log('Connected to Tether');
+            this.onOpen();
+            if (this.sendQueue.length > 0) {
+                this.sendQueue.forEach(message => this.ws?.send(message));
+                this.sendQueue = [];
+            }
+            this.reconnectAttempts = 0;
+        };
+
+        ws.onmessage = (event: MessageEvent) => {
+            const data = JSON.parse(String(event.data)) as {
+                type: string;
+                query?: string;
+                data?: unknown;
+                error?: string;
+            };
+            if (data.type === 'query') {
+                this.subscribedQueries.forEach((callback, query) => {
+                    if (data.query === query) {
+                        callback(data.data);
+                    }
+                });
+            } else if (data.type === 'error') {
+                console.error(data.error);
+            }
+        };
+
+        ws.onclose = () => {
+            console.log('Disconnected from Tether');
+            this.attemptReconnect();
+        };
+    };
+
+    attemptReconnect = () => {
+        this.ws?.close();
+        this.reconnectAttempts++;
+        if (this.reconnectAttempts > this.maxReconnectAttempts) {
+            console.error('Max reconnect attempts reached');
+            return;
+        }
+        setTimeout(() => {
+            this.startConnection(this.url);
+        }, this.reconnectInterval);
+    };
+
+    close = () => {
+        this.ws?.close();
+        this.ws = null;
+    };
+
+    send = (message: string) => {
+        if (this.ws?.readyState !== WebSocket.OPEN) {
+            this.sendQueue.push(message);
+            return;
+        }
+        this.ws?.send(message);
+    };
+}