From 9608ed9fdfbfe6ff6b2cddad35e2d39bed27f7ea Mon Sep 17 00:00:00 2001
From: Francois BIOT <hsaturn@gmail.com>
Date: Wed, 28 Dec 2022 20:22:31 +0100
Subject: [PATCH] Added example for MqttClassBinder

---
 .../mqtt_class_binder/mqtt_class_binder.ino   | 134 ++++++++++++++++++
 1 file changed, 134 insertions(+)
 create mode 100644 examples/advanced/mqtt_class_binder/mqtt_class_binder.ino

diff --git a/examples/advanced/mqtt_class_binder/mqtt_class_binder.ino b/examples/advanced/mqtt_class_binder/mqtt_class_binder.ino
new file mode 100644
index 0000000..44f1ee3
--- /dev/null
+++ b/examples/advanced/mqtt_class_binder/mqtt_class_binder.ino
@@ -0,0 +1,134 @@
+#include <TinyMqtt.h>   // https://github.com/hsaturn/TinyMqtt
+#include <MqttClassBinder.h>
+
+/** 
+  * Example on how to bind a class:onPublish function
+  *
+  * Local broker that accept connections and two local clients
+  *
+  * 
+  *  +-----------------------------+
+  *  | ESP                         |
+  *  |                 +--------+  | 1883 <--- External client/s
+  *  |       +-------->| broker |  | 1883 <--- External client/s
+  *  |       |         +--------+  |
+  *  |       |             ^       |
+  *  |       |             |       |
+  *  |       |             |       |     -----
+  *  |       v             v       |      ---  
+  *  | +----------+  +----------+  |       -  
+  *  | | internal |  | internal |  +-------*  Wifi
+  *  | | client   |  | client   |  |          
+  *  | +----------+  +----------+  |          
+  *  |                             |
+  *  +-----------------------------+
+  * 
+  * pros - Reduces internal latency (when publish is received by the same ESP)
+  *      - Reduces wifi traffic
+  *      - No need to have an external broker
+  *      - can still report to a 'main' broker (TODO see documentation that have to be written)
+  *      - accepts external clients
+  *      - MqttClassBinder allows to mix together many mqtt sources
+  *
+  * cons - Takes more memory (48 more bytes for the one MqttClassBinder<Class>
+  *      - a bit hard to understand
+  *
+  */
+
+const char *ssid     = "Freebox-786A2F";
+const char *password = "usurpavi8dalum64lumine?";
+
+std::string topic_b="sensor/btemp";
+std::string topic_sender= "sensor/counter";
+
+MqttBroker broker(1883);
+
+MqttClient mqtt_a(&broker);
+MqttClient mqtt_b(&broker);
+MqttClient mqtt_sender(&broker);
+
+class MqttReceiver: public MqttClassBinder<MqttReceiver>
+{
+  public:
+  
+    void onPublish(const MqttClient* source, const Topic& topic, const char* payload, size_t /* length */)
+    {
+      Serial
+        << "   * MqttReceiver received topic (" << topic.c_str() << ")"
+        << " from (" << source->id() << "), "
+        << " payload: (" << payload << ')' << endl;
+    }
+};
+
+void setup()
+{
+  Serial.begin(115200);
+  delay(500);
+  Serial << "Clients with wifi " << endl;
+
+  WiFi.mode(WIFI_STA);
+  WiFi.begin(ssid, password);
+
+  while (WiFi.status() != WL_CONNECTED)
+  {
+    Serial << '-'; delay(500);
+  	if (strlen(ssid)==0)
+	  	Serial << "****** PLEASE EDIT THE EXAMPLE AND MODIFY ssid/password *************" << endl;
+  }
+
+  Serial << "Connected to " << ssid << "IP address: " << WiFi.localIP() << endl;
+
+  broker.begin();
+
+  MqttReceiver* receiver = new MqttReceiver;
+
+  // receiver will receive both publication from two MqttClient
+  // (that could be connected to two different brokers)
+  MqttClassBinder<MqttReceiver>::onPublish(&mqtt_a, receiver);
+  MqttClassBinder<MqttReceiver>::onPublish(&mqtt_b, receiver);
+
+  mqtt_a.id("mqtt_a");
+  mqtt_b.id("mqtt_b");
+  mqtt_sender.id("sender");
+
+  mqtt_a.subscribe(topic_b);
+  mqtt_b.subscribe(topic_sender);
+
+}
+
+void loop()
+{
+  broker.loop();  // Don't forget to add loop for every broker and clients
+
+  mqtt_a.loop();
+  mqtt_b.loop();
+  mqtt_sender.loop();
+
+  // ============= client A publish ================
+  {
+    static const int interval = 5000;  // publishes every 5s (please avoid usage of delay())
+    static uint32_t timer = millis() + interval;
+
+    if (millis() > timer)
+    {
+      static int counter = 0;
+      Serial << "Sender is publishing " << topic_sender.c_str() << endl;
+      timer += interval;
+      mqtt_sender.publish(topic_sender, "sent by Sender, message #"+std::string(String(counter++).c_str()));
+    }
+  }
+
+  // ============= client B publish ================
+  {
+    static const int interval = 7000;	// will send topic each 7s
+    static uint32_t timer = millis() + interval;
+    static int temperature;
+
+    if (millis() > timer)
+    {
+      Serial << "B is publishing " << topic_b.c_str() << endl;
+      timer += interval;
+      mqtt_b.publish(topic_b, "sent by B: temp="+std::string(String(16+temperature++%6).c_str()));
+    }
+  }
+}