From a5f9238183bdbbd4b57c8346b1d76d1351f37320 Mon Sep 17 00:00:00 2001
From: James Rich <2199651+jamesarich@users.noreply.github.com>
Date: Fri, 19 Jun 2026 13:23:37 -0500
Subject: [PATCH] fix(network): retry transient connection/IO failures to
 api.meshtastic.org (#5870)

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>
---
 .../org/meshtastic/app/di/NetworkModule.kt    |  6 ++----
 .../core/network/HttpClientDefaults.kt        | 19 +++++++++++++++++--
 .../desktop/di/DesktopKoinModule.kt           |  6 ++----
 3 files changed, 21 insertions(+), 10 deletions(-)

diff --git a/androidApp/src/main/kotlin/org/meshtastic/app/di/NetworkModule.kt b/androidApp/src/main/kotlin/org/meshtastic/app/di/NetworkModule.kt
index f4d90ec13..bd88dafb8 100644
--- a/androidApp/src/main/kotlin/org/meshtastic/app/di/NetworkModule.kt
+++ b/androidApp/src/main/kotlin/org/meshtastic/app/di/NetworkModule.kt
@@ -48,6 +48,7 @@ import org.koin.core.annotation.Single
 import org.meshtastic.core.common.BuildConfigProvider
 import org.meshtastic.core.network.HttpClientDefaults
 import org.meshtastic.core.network.KermitHttpLogger
+import org.meshtastic.core.network.configureDefaultRetry
 
 private const val DISK_CACHE_PERCENT = 0.02
 private const val MEMORY_CACHE_PERCENT = 0.25
@@ -104,10 +105,7 @@ class NetworkModule {
                 connectTimeoutMillis = HttpClientDefaults.TIMEOUT_MS
                 socketTimeoutMillis = HttpClientDefaults.TIMEOUT_MS
             }
-            install(plugin = HttpRequestRetry) {
-                retryOnServerErrors(maxRetries = HttpClientDefaults.MAX_RETRIES)
-                exponentialDelay()
-            }
+            install(plugin = HttpRequestRetry) { configureDefaultRetry() }
             if (buildConfigProvider.isDebug) {
                 install(plugin = Logging) {
                     logger = KermitHttpLogger
diff --git a/core/network/src/commonMain/kotlin/org/meshtastic/core/network/HttpClientDefaults.kt b/core/network/src/commonMain/kotlin/org/meshtastic/core/network/HttpClientDefaults.kt
index 87c317024..35694f87f 100644
--- a/core/network/src/commonMain/kotlin/org/meshtastic/core/network/HttpClientDefaults.kt
+++ b/core/network/src/commonMain/kotlin/org/meshtastic/core/network/HttpClientDefaults.kt
@@ -16,8 +16,10 @@
  */
 package org.meshtastic.core.network
 
+import io.ktor.client.plugins.HttpRequestRetryConfig
+
 /**
- * Shared HTTP client configuration constants used by both Android and Desktop Ktor `HttpClient` setups.
+ * Shared HTTP client configuration used by both Android and Desktop Ktor `HttpClient` setups.
  *
  * These values are consumed by the platform-specific Koin modules (`NetworkModule` on Android, `DesktopKoinModule` on
  * Desktop) when installing [io.ktor.client.plugins.HttpTimeout] and [io.ktor.client.plugins.HttpRequestRetry].
@@ -26,9 +28,22 @@ object HttpClientDefaults {
     /** Timeout in milliseconds for connect, request, and socket operations. */
     const val TIMEOUT_MS = 30_000L
 
-    /** Maximum number of automatic retries on server errors (5xx). */
+    /** Maximum number of automatic retries on server errors (5xx) and transient connection/IO failures. */
     const val MAX_RETRIES = 3
 
     /** Base URL for the Meshtastic public API. Installed via the `DefaultRequest` plugin. */
     const val API_BASE_URL = "https://api.meshtastic.org/"
 }
+
+/**
+ * Shared [io.ktor.client.plugins.HttpRequestRetry] policy for both engines.
+ *
+ * Retries on 5xx server errors and on transient connection/IO failures (dropped sockets, DNS blips, read timeouts) —
+ * the common failure mode on flaky cellular — with exponential backoff. [HttpClientDefaults.MAX_RETRIES] applies to
+ * both rules.
+ */
+fun HttpRequestRetryConfig.configureDefaultRetry() {
+    retryOnServerErrors(maxRetries = HttpClientDefaults.MAX_RETRIES)
+    retryOnException(maxRetries = HttpClientDefaults.MAX_RETRIES, retryOnTimeout = true)
+    exponentialDelay()
+}
diff --git a/desktopApp/src/main/kotlin/org/meshtastic/desktop/di/DesktopKoinModule.kt b/desktopApp/src/main/kotlin/org/meshtastic/desktop/di/DesktopKoinModule.kt
index 3e7826074..06f70f534 100644
--- a/desktopApp/src/main/kotlin/org/meshtastic/desktop/di/DesktopKoinModule.kt
+++ b/desktopApp/src/main/kotlin/org/meshtastic/desktop/di/DesktopKoinModule.kt
@@ -44,6 +44,7 @@ import org.meshtastic.core.model.NetworkDeviceLink
 import org.meshtastic.core.model.NetworkFirmwareReleases
 import org.meshtastic.core.network.HttpClientDefaults
 import org.meshtastic.core.network.KermitHttpLogger
+import org.meshtastic.core.network.configureDefaultRetry
 import org.meshtastic.core.network.repository.MQTTRepository
 import org.meshtastic.core.network.service.ApiService
 import org.meshtastic.core.network.service.ApiServiceImpl
@@ -245,10 +246,7 @@ private fun desktopPlatformStubsModule() = module {
                 connectTimeoutMillis = HttpClientDefaults.TIMEOUT_MS
                 socketTimeoutMillis = HttpClientDefaults.TIMEOUT_MS
             }
-            install(HttpRequestRetry) {
-                retryOnServerErrors(maxRetries = HttpClientDefaults.MAX_RETRIES)
-                exponentialDelay()
-            }
+            install(HttpRequestRetry) { configureDefaultRetry() }
             if (DesktopBuildConfig.IS_DEBUG) {
                 install(Logging) {
                     logger = KermitHttpLogger