lukas/websocket improvements

sdk/src/accounts/README_WebSocketAccountSubscriberV2.md

@@ -31,6 +31,46 @@ await subscriber.subscribe((data) => {
 await subscriber.unsubscribe();
 ```
 
+### Polling Instead of Resubscribing
+
+For accounts that rarely update (like long-tail markets), you can use polling instead of resubscribing to reduce resource usage:
+
+```typescript
+const resubOpts = {
+	resubTimeoutMs: 30000, // 30 seconds
+	logResubMessages: true,
+	usePollingInsteadOfResub: true, // Enable polling mode
+	pollingIntervalMs: 30000, // Poll every 30 seconds (optional, defaults to 30000)
+};
+
+const subscriber = new WebSocketAccountSubscriberV2(
+	'perpMarket', // account name
+	program,
+	marketPublicKey,
+	undefined, // decodeBuffer
+	resubOpts
+);
+```
+
+**How it works:**
+1. Initially subscribes to WebSocket updates
+2. If no WebSocket data is received for `resubTimeoutMs` (30s), switches to polling mode if `usePollingInsteadOfResub` is specified true, else just resubscribes(unsub, sub).
+3. Polls every `pollingIntervalMs` (30s) to check for updates by:
+   - Storing current account buffer state
+   - Fetching latest account data
+   - Comparing buffers to detect any missed updates
+4. If polling detects new data (indicating missed WebSocket events):
+   - Immediately stops polling
+   - Resubscribes to WebSocket to restore real-time updates
+   - This helps recover from degraded WebSocket connections
+5. If a WebSocket event is received while polling:
+   - Polling is automatically stopped
+   - System continues with normal WebSocket updates
+6. This approach provides:
+   - Efficient handling of rarely-updated accounts
+   - Automatic recovery from WebSocket connection issues
+   - Seamless fallback between polling and WebSocket modes
+
 ## Implementation Details
 
 ### Gill Integration
@@ -52,3 +92,4 @@ const { rpc, rpcSubscriptions } = createSolanaClient({
 3. **Address Handling**: Converts `PublicKey` to gill's `Address` type for compatibility
 4. **Response Formatting**: Converts gill responses to match the expected `AccountInfo<Buffer>` format
 5. **Abort Signal**: Utilizes AbortSignal nodejs/web class to shutdown websocket connection synchronously
+6. **Polling Mode**: Optional polling mechanism for accounts that rarely update

sdk/src/accounts/types.ts

@@ -202,6 +202,9 @@ export type DataAndSlot<T> = {
 export type ResubOpts = {
 	resubTimeoutMs?: number;
 	logResubMessages?: boolean;
+	// New options for polling-based resubscription
+	usePollingInsteadOfResub?: boolean;
+	pollingIntervalMs?: number;
 };
 
 export interface UserStatsAccountEvents {