add notification sending logic

src/notifications/senders/AppleNotificationSender.ts

@@ -1,4 +1,5 @@
 import jwt from "jsonwebtoken";
+import http2 from "http2";
 
 interface APNsUrl {
   fullUrl: string;
@@ -6,6 +7,11 @@ interface APNsUrl {
   host: string;
 }
 
+interface NotificationAlertArguments {
+  title: string;
+  body: string;
+}
+
 class AppleNotificationSender {
   private apnsToken: string | undefined = undefined;
   private _lastRefreshedTimeMs: number | undefined = undefined;
@@ -45,8 +51,56 @@ class AppleNotificationSender {
     this._lastRefreshedTimeMs = nowMs;
   }
 
-  public sendNotificationImmediately(notification: any) {
-    // TODO Send the notification
+  /**
+   * Send a notification immediately.
+   * @param deviceId
+   * @param notificationAlertArguments
+   *
+   * @return Boolean promise indicating whether the
+   * notification was sent successfully.
+   */
+  public async sendNotificationImmediately(deviceId: string, notificationAlertArguments: NotificationAlertArguments) {
+    const bundleId = process.env.APNS_BUNDLE_ID;
+    if (typeof bundleId !== "string") {
+      throw new Error("APNS_BUNDLE_ID environment variable is not set correctly");
+    }
+
+    const { path, host } = AppleNotificationSender.getAPNsFullUrlToUse(deviceId);
+
+    const headers = {
+      ':method': 'POST',
+      ':path': path,
+      'authorization': `bearer ${this.apnsToken}`,
+      "apns-push-type": "alert",
+      "apns-expiration": "0",
+      "apns-priority": "10",
+      "apns-topic": bundleId,
+    };
+    try {
+      const client = http2.connect(host);
+      const req = client.request(headers);
+      req.setEncoding('utf8');
+
+      await new Promise<void>((resolve, reject) => {
+        req.on('response', (headers, flags) => {
+          if (headers[":status"] !== 200) {
+            reject(`APNs request failed with status ${headers[":status"]}`);
+          }
+          resolve();
+        });
+
+        req.write(JSON.stringify({
+          aps: {
+            alert: notificationAlertArguments,
+          }
+        }));
+        req.end();
+      });
+      return true;
+    } catch(e) {
+      console.error(e);
+      return false;
+    }
   }
 
   public static getAPNsFullUrlToUse(deviceId: string): APNsUrl {