add function to check if session is connected

Author: Mahad-10

lib/session.ts

@@ -78,6 +78,10 @@ export class Session {
         await this._baseSession.close();
     }
 
+    isConnected(): boolean {
+        return this._baseSession.isConnected();
+    }
+
     private async _processIncomingMessage(message: Message): Promise<void> {
         if (message instanceof ResultMsg) {
             const promiseHandler = this._callRequests.get(message.requestID);

lib/types.ts

@@ -44,6 +44,10 @@ export abstract class IBaseSession {
     async close(): Promise<void> {
         throw new Error("UnimplementedError");
     }
+
+    isConnected(): boolean {
+        throw new Error("UnimplementedError");
+    }
 }
 
 export class BaseSession extends IBaseSession {
@@ -126,6 +130,10 @@ export class BaseSession extends IBaseSession {
 
         this._ws.close();
     }
+
+    isConnected(): boolean {
+        return this._ws.readyState === WebSocket.OPEN;
+    }
 }
 
 export class Result {