From 481fe19efb7b943728a2de65ebfa320d1312deb1 Mon Sep 17 00:00:00 2001
From: Andrew <andrew@signal.org>
Date: Thu, 16 Oct 2025 22:43:26 -0400
Subject: [PATCH] Add support for new bandwidthConstrainedOk flag used to
 deliver notifications to sat networks

---
 .../firebase/messaging/AndroidConfig.java     | 14 +++++++++++
 .../firebase/messaging/MessageTest.java       | 23 +++++++++++++++++++
 2 files changed, 37 insertions(+)

diff --git a/src/main/java/com/google/firebase/messaging/AndroidConfig.java b/src/main/java/com/google/firebase/messaging/AndroidConfig.java
index e38e561d0..775978788 100644
--- a/src/main/java/com/google/firebase/messaging/AndroidConfig.java
+++ b/src/main/java/com/google/firebase/messaging/AndroidConfig.java
@@ -55,6 +55,9 @@ public class AndroidConfig {
   @Key("direct_boot_ok")
   private final Boolean directBootOk;
 
+  @Key("bandwidth_constrained_ok")
+  private final Boolean bandwidthConstrainedOk;
+
   private AndroidConfig(Builder builder) {
     this.collapseKey = builder.collapseKey;
     if (builder.priority != null) {
@@ -79,6 +82,7 @@ private AndroidConfig(Builder builder) {
     this.notification = builder.notification;
     this.fcmOptions = builder.fcmOptions;
     this.directBootOk = builder.directBootOk;
+    this.bandwidthConstrainedOk = builder.bandwidthConstrainedOk;
   }
 
   /**
@@ -108,6 +112,7 @@ public static class Builder {
     private AndroidNotification notification;
     private AndroidFcmOptions fcmOptions;
     private Boolean directBootOk;
+    private Boolean bandwidthConstrainedOk;
 
     private Builder() {}
 
@@ -218,6 +223,15 @@ public Builder setDirectBootOk(boolean directBootOk) {
       return this;
     }
 
+    /**
+     * Sets the {@code bandwidth_constrained_ok} flag. If set to true, messages can be delivered
+     * even when the device is connected through a bandwidth-constrained network.
+     */
+    public Builder setBandwidthConstrainedOk(boolean bandwidthConstrainedOk) {
+      this.bandwidthConstrainedOk = bandwidthConstrainedOk;
+      return this;
+    }
+
     /**
      * Creates a new {@link AndroidConfig} instance from the parameters set on this builder.
      *
diff --git a/src/test/java/com/google/firebase/messaging/MessageTest.java b/src/test/java/com/google/firebase/messaging/MessageTest.java
index 4ac1782ba..14b53bd2a 100644
--- a/src/test/java/com/google/firebase/messaging/MessageTest.java
+++ b/src/test/java/com/google/firebase/messaging/MessageTest.java
@@ -224,6 +224,29 @@ public void testAndroidMessageWithDirectBootOk() throws IOException {
     assertJsonEquals(ImmutableMap.of("topic", "test-topic", "android", data), message);
   }
 
+  @Test
+  public void testAndroidMessageWithBandwidthConstrainedOk() throws IOException {
+    Message message = Message.builder()
+        .setAndroidConfig(AndroidConfig.builder()
+            .setBandwidthConstrainedOk(true)
+            .setNotification(AndroidNotification.builder()
+                .setTitle("android-title")
+                .setBody("android-body")
+                .build())
+            .build())
+        .setTopic("test-topic")
+        .build();
+    Map<String, Object> notification = ImmutableMap.<String, Object>builder()
+        .put("title", "android-title")
+        .put("body", "android-body")
+        .build();
+    Map<String, Object> data = ImmutableMap.of(
+        "bandwidth_constrained_ok", true,
+        "notification", notification
+    );
+    assertJsonEquals(ImmutableMap.of("topic", "test-topic", "android", data), message);
+  }
+
   @Test(expected = IllegalArgumentException.class)
   public void testAndroidNotificationWithNegativeCount() throws IllegalArgumentException {
     AndroidNotification.builder().setNotificationCount(-1).build();