1 files changed, 9 insertions, 0 deletions

diff --git a/main/cvm_server.c b/main/cvm_server.c
index 10af956..f3a5ab8 100644
--- a/main/cvm_server.c
+++ b/main/cvm_server.c
@@ -31,6 +31,7 @@ static void publish_announcements_via_ws(esp_tls_t *tls);
 #define CVM_WS_BUF_SIZE 8192
 #define CVM_MAX_RESPONSE_SIZE 4096
 #define CVM_RECONNECT_DELAY_MS 5000
+#define CVM_WS_PING_INTERVAL_S 30
 
 static char *parse_ws_text_frame(const uint8_t *buf, int len)
 {
@@ -554,6 +555,7 @@ static void cvm_relay_task(void *arg)
             return;
         }
 
+        int64_t last_ping_time = (int64_t)(xTaskGetTickCount() * portTICK_PERIOD_MS) / 1000;
         int consecutive_timeouts = 0;
         while (g_running) {
             int rlen = esp_tls_conn_read(tls, buf, CVM_WS_BUF_SIZE - 1);
@@ -583,6 +585,13 @@ static void cvm_relay_task(void *arg)
                 }
             }
 
+            int64_t now = (int64_t)(xTaskGetTickCount() * portTICK_PERIOD_MS) / 1000;
+            if (now - last_ping_time >= CVM_WS_PING_INTERVAL_S) {
+                uint8_t ping[2] = {0x89, 0x00};
+                esp_tls_conn_write(tls, ping, 2);
+                last_ping_time = now;
+                ESP_LOGD(TAG, "Sent WS keepalive ping");
+            }
         }
 
         free(buf);