From e58929dfc0310866481a2dcc9e37e4f70247c1e4 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Xose=20P=C3=A9rez?= <xose.perez@gmail.com>
Date: Tue, 5 Dec 2017 15:47:27 +0100
Subject: [PATCH] Limit size of the MQTT queue to 10 messages when useJson is
 enabled

---
 code/espurna/config/general.h | 2 ++
 code/espurna/mqtt.ino         | 4 ++++
 2 files changed, 6 insertions(+)

diff --git a/code/espurna/config/general.h b/code/espurna/config/general.h
index 48644f5b..912a7ff0 100644
--- a/code/espurna/config/general.h
+++ b/code/espurna/config/general.h
@@ -419,6 +419,8 @@ PROGMEM const char* const custom_reset_string[] = {
 
 #define MQTT_USE_JSON           0           // Group messages in a JSON body
 #define MQTT_USE_JSON_DELAY     100         // Wait this many ms before grouping messages
+#define MQTT_QUEUE_MAX_SIZE     10          // Size of the MQTT queue when MQTT_USE_JSON is enabled
+
 
 // These particles will be concatenated to the MQTT_TOPIC base to form the actual topic
 #define MQTT_TOPIC_JSON         "data"
diff --git a/code/espurna/mqtt.ino b/code/espurna/mqtt.ino
index bec70f2b..d6e69b5f 100644
--- a/code/espurna/mqtt.ino
+++ b/code/espurna/mqtt.ino
@@ -140,11 +140,15 @@ void _mqttFlush() {
 void mqttSend(const char * topic, const char * message, bool force) {
     bool useJson = force ? false : _mqtt_use_json;
     if (useJson) {
+
+        if (_mqtt_queue.size() >= MQTT_QUEUE_MAX_SIZE) _mqttFlush();
+
         mqtt_message_t element;
         element.topic = strdup(topic);
         element.message = strdup(message);
         _mqtt_queue.push_back(element);
         _mqtt_flush_ticker.once_ms(MQTT_USE_JSON_DELAY, _mqttFlush);
+        
     } else {
         String path = _mqtt_topic + String(topic) + _mqtt_getter;
         mqttSendRaw(path.c_str(), message);