From 0b1333404ccc0f9fba704ffd50548f63234ebe67 Mon Sep 17 00:00:00 2001
From: Tyler Payne <paynetyler@censystech.com>
Date: Wed, 10 Jun 2026 17:48:27 +0000
Subject: [PATCH 1/2] feat(core): add FeedHeartbeatWatchdog RPC

Allow a client to keep MAVSDK's periodic heartbeats alive by feeding a
deadman timer (configured in MAVSDK), so heartbeats stop when the
client hangs or dies.
---
 protos/core/core.proto | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/protos/core/core.proto b/protos/core/core.proto
index 3df5592be..a35994a10 100644
--- a/protos/core/core.proto
+++ b/protos/core/core.proto
@@ -20,6 +20,21 @@ service CoreService {
      * need to be increased to prevent timeouts.
      */
     rpc SetMavlinkTimeout(SetMavlinkTimeoutRequest) returns(SetMavlinkTimeoutResponse) {}
+    /*
+     * Feed the heartbeat watchdog.
+     *
+     * MAVSDK can be configured with a heartbeat watchdog (deadman timer).
+     * While configured, the periodic heartbeats sent by MAVSDK are only sent
+     * as long as this is called at least once per timeout period. If the
+     * watchdog times out, heartbeats stop until it is fed again.
+     *
+     * This allows MAVSDK's heartbeats to reflect the liveness of the client:
+     * if the client hangs or dies, heartbeats stop.
+     *
+     * Has no effect if no watchdog is configured (e.g. with the
+     * --heartbeat-watchdog-timeout option of mavsdk_server).
+     */
+    rpc FeedHeartbeatWatchdog(FeedHeartbeatWatchdogRequest) returns(FeedHeartbeatWatchdogResponse) {}
 }
 
 message SubscribeConnectionStateRequest {}
@@ -32,6 +47,9 @@ message SetMavlinkTimeoutRequest {
 }
 message SetMavlinkTimeoutResponse {}
 
+message FeedHeartbeatWatchdogRequest {}
+message FeedHeartbeatWatchdogResponse {}
+
 // Connection state type.
 message ConnectionState {
     bool is_connected = 2; // Whether the vehicle got connected or disconnected

From d019861782e03586efd24de81bebf5c8f4d19c9c Mon Sep 17 00:00:00 2001
From: Tyler Payne <paynetyler@censystech.com>
Date: Wed, 8 Jul 2026 15:17:14 +0000
Subject: [PATCH 2/2] feat(core): add SetHeartbeatWatchdogTimeout RPC

Add a gRPC path to enable or disable the heartbeat watchdog at runtime.
timeout_s is a double in seconds: 0 disables the watchdog, and values
greater than 0 must be at least 1 (timeouts between 0 and 1 are invalid).
---
 protos/core/core.proto | 25 ++++++++++++++++++++++++-
 1 file changed, 24 insertions(+), 1 deletion(-)

diff --git a/protos/core/core.proto b/protos/core/core.proto
index a35994a10..2042d1b0c 100644
--- a/protos/core/core.proto
+++ b/protos/core/core.proto
@@ -32,9 +32,27 @@ service CoreService {
      * if the client hangs or dies, heartbeats stop.
      *
      * Has no effect if no watchdog is configured (e.g. with the
-     * --heartbeat-watchdog-timeout option of mavsdk_server).
+     * --heartbeat-watchdog-timeout option of mavsdk_server, or
+     * SetHeartbeatWatchdogTimeout).
      */
     rpc FeedHeartbeatWatchdog(FeedHeartbeatWatchdogRequest) returns(FeedHeartbeatWatchdogResponse) {}
+    /*
+     * Set the heartbeat watchdog timeout.
+     *
+     * When timeout_s is greater than 0, the periodic heartbeats sent by MAVSDK
+     * are only sent as long as FeedHeartbeatWatchdog is called at least once
+     * per timeout period. If the watchdog times out, heartbeats stop until it
+     * is fed again.
+     *
+     * When timeout_s is 0, the watchdog is disabled and heartbeats follow the
+     * usual policy (always_send_heartbeats or a connected system).
+     *
+     * Values greater than 0 and less than 1 are rejected.
+     *
+     * This is an alternative to configuring the watchdog at mavsdk_server
+     * startup with the --heartbeat-watchdog-timeout option.
+     */
+    rpc SetHeartbeatWatchdogTimeout(SetHeartbeatWatchdogTimeoutRequest) returns(SetHeartbeatWatchdogTimeoutResponse) {}
 }
 
 message SubscribeConnectionStateRequest {}
@@ -50,6 +68,11 @@ message SetMavlinkTimeoutResponse {}
 message FeedHeartbeatWatchdogRequest {}
 message FeedHeartbeatWatchdogResponse {}
 
+message SetHeartbeatWatchdogTimeoutRequest {
+    double timeout_s = 1; // Timeout in seconds. 0 disables the watchdog. Minimum 1 when enabled.
+}
+message SetHeartbeatWatchdogTimeoutResponse {}
+
 // Connection state type.
 message ConnectionState {
     bool is_connected = 2; // Whether the vehicle got connected or disconnected