feat: get registration state from the gateway (#366)

packages/js/README.md

@@ -190,6 +190,15 @@ client.newCall({
 });
 ```
 
+### Getting the Registration State
+
+To retrieve the registration state from the server gateway you can
+use `client.getIsRegistered` method
+
+```js
+client.getIsRegistered().then(isRegistered => {...})
+```
+
 ---
 
 ## Examples

packages/js/src/Modules/Verto/BaseSession.ts

@@ -8,6 +8,7 @@ import {
   register,
   trigger,
 } from './services/Handler';
+import { RegisterAgent } from './services/RegisterAgent';
 import { SwEvent } from './util/constants';
 import { isFunction, isValidOptions, randomInt } from './util/helpers';
 import { BroadcastParams, IVertoOptions } from './util/interfaces';
@@ -36,6 +37,7 @@ export default abstract class BaseSession {
 
   private _executeQueue: { resolve?: Function; msg: any }[] = [];
   private _pong: boolean;
+  private registerAgent: RegisterAgent;
 
   constructor(public options: IVertoOptions) {
     if (!this.validateOptions()) {
@@ -48,6 +50,7 @@ export default abstract class BaseSession {
 
     this._attachListeners();
     this.connection = new Connection(this);
+    this.registerAgent = new RegisterAgent(this);
   }
 
   get __logger(): log.Logger {
@@ -412,4 +415,12 @@ export default abstract class BaseSession {
   public hasAutoReconnect() {
     return this._autoReconnect;
   }
+
+  /**
+   * Get the registration state of the client
+   * @return Promise<boolean>
+   */
+  public getIsRegistered() {
+    return this.registerAgent.getIsRegistered();
+  }
 }

packages/js/src/Modules/Verto/services/RegisterAgent.ts

@@ -0,0 +1,39 @@
+import BaseSession from '../BaseSession';
+import { Gateway } from '../messages/verto/Gateway';
+import {
+  deferredPromise,
+  DeferredPromise,
+  getGatewayState,
+} from '../util/helpers';
+import { GatewayStateType } from '../webrtc/constants';
+
+export class RegisterAgent {
+  private session: BaseSession;
+  private gatewayStateTask: DeferredPromise<GatewayStateType | ''>;
+  private pendingRequestId: string | null = null;
+
+  constructor(session: BaseSession) {
+    this.session = session;
+    this.gatewayStateTask = deferredPromise<GatewayStateType>({});
+    this.session.on('telnyx.socket.message', this.onSocketMessage);
+  }
+
+  public onSocketMessage = async (response) => {
+    if (response.id === this.pendingRequestId) {
+      this.gatewayStateTask.resolve(getGatewayState(response));
+    }
+  };
+
+  public getIsRegistered = async () => {
+    const message = new Gateway();
+    this.pendingRequestId = message.request.id;
+    this.gatewayStateTask = deferredPromise<GatewayStateType>({});
+
+    this.session.execute(message);
+    const state = await this.gatewayStateTask.promise;
+    if (!state) {
+      return false;
+    }
+    return [GatewayStateType.REGISTER, GatewayStateType.REGED].includes(state);
+  };
+}