feat(fcm): Support proxy field in FCM AndroidNotification (#2874)

* feat(fcm): Support `proxy` field on `AndroidNotification`

* update doc string

* fix: Update `proxy` and `visibility` doc string with TW suggestion

Author: jonathanedey

Diff for: etc/firebase-admin.messaging.api.md

@@ -43,6 +43,7 @@ export interface AndroidNotification {
     localOnly?: boolean;
     notificationCount?: number;
     priority?: ('min' | 'low' | 'default' | 'high' | 'max');
+    proxy?: ('allow' | 'deny' | 'if_priority_lowered');
     sound?: string;
     sticky?: boolean;
     tag?: string;

Diff for: src/messaging/messaging-api.ts

@@ -593,7 +593,8 @@ export interface AndroidNotification {
 
   /**
    * Sets the visibility of the notification. Must be either `private`, `public`,
-   * or `secret`. If unspecified, defaults to `private`.
+   * or `secret`. If unspecified, it remains undefined in the Admin SDK, and
+   * defers to the FCM backend's default mapping.
    */
   visibility?: ('private' | 'public' | 'secret');
 
@@ -608,6 +609,13 @@ export interface AndroidNotification {
    * displayed on the long-press menu each time a new notification arrives.
    */
   notificationCount?: number;
+
+  /**
+   * Sets if this notification should attempt to be proxied. Must be either
+   * `allow`, `deny` or `if_priority_lowered`. If unspecified, it remains
+   * undefined in the Admin SDK, and defers to the FCM backend's default mapping.
+   */
+  proxy?: ('allow' | 'deny' | 'if_priority_lowered');
 }
 
 /**

Diff for: src/messaging/messaging-internal.ts

@@ -475,6 +475,11 @@ function validateAndroidNotification(notification: AndroidNotification | undefin
     (notification as any).priority = priority;
   }
 
+  if (typeof notification.proxy !== 'undefined') {
+    const proxy = notification.proxy.toUpperCase();
+    (notification as any).proxy = proxy;
+  }
+
   if (typeof notification.visibility !== 'undefined') {
     const visibility = notification.visibility.toUpperCase();
     (notification as any).visibility = visibility;

Diff for: test/integration/messaging.spec.ts

@@ -64,6 +64,7 @@ const message: Message = {
       },
       defaultLightSettings: false,
       notificationCount: 1,
+      proxy: 'if_priority_lowered',
     },
   },
   apns: {

Diff for: test/unit/messaging/messaging.spec.ts

@@ -1855,6 +1855,7 @@ describe('Messaging', () => {
               ticker: 'test.ticker',
               sticky: true,
               visibility: 'private',
+              proxy: 'deny',
             },
           },
         },
@@ -1871,6 +1872,7 @@ describe('Messaging', () => {
               ticker: 'test.ticker',
               sticky: true,
               visibility: 'PRIVATE',
+              proxy: 'DENY'
             },
           },
         },
@@ -2001,6 +2003,7 @@ describe('Messaging', () => {
               },
               defaultLightSettings: false,
               notificationCount: 1,
+              proxy: 'if_priority_lowered',
             },
             fcmOptions: {
               analyticsLabel: 'test.analytics',
@@ -2053,6 +2056,7 @@ describe('Messaging', () => {
               },
               default_light_settings: false,
               notification_count: 1,
+              proxy: 'IF_PRIORITY_LOWERED',
             },
             fcmOptions: {
               analyticsLabel: 'test.analytics',