MQTT initialization

firmware/esp32/main/mqtt.cpp

@@ -8,22 +8,45 @@
 
 static const char* TAG = "MQTT";
 
-static void mqtt_init(void) {}
+
+static void mqtt_init(void) {
+    // TODO; implement Trust only or Mutual TLS in the future (and secure boot + flash encryption)
+    const esp_mqtt_client_config_t mqtt_cfg = {
+        .broker = {
+            //TODO: make this a definition in config.hpp
+            .address.uri = "mqtt://yourmqttserver",
+            .address.port = 1883
+        },
+
+        esp_mqtt_client_handle_t client = esp_mqtt_client_init(&mqtt_cfg);
+        mqttClient = client;
+        /* The last argument may be used to pass data to the event handler, in this example mqtt_event_handler */
+        esp_mqtt_client_register_event(client, ESP_EVENT_ANY_ID, mqtt_event_handler, NULL);
+        esp_mqtt_client_start(client);
+}
+
+static void mqtt_subscribe(void) {
+    msg_id = esp_mqtt_client_subscribe(client, "/topic/qos0", 0);
+}
 
 static void mqtt_publish(void) {}
 
+static void mqtt_fetch(void) {}
+
 void mqttTask(void *pvParameters) {
     ESP_LOGI(TAG, "Task started");
 
     mqtt_init();
     ESP_ERROR_CHECK(esp_task_wdt_add(NULL));
 
-
     for(;;) {
         ESP_LOGI(TAG, "Checking Wi-Fi connection...");
         xEventGroupWaitBits(wifi_event_group, WIFI_CONNECTED_BIT, pdFALSE, pdTRUE, portMAX_DELAY);
 
-        if (bits & WIFI_CONNECTED_BIT) mqtt_publish();
+        if (bits & WIFI_CONNECTED_BIT) {
+            mqtt_publish();
+            mqtt_fetch();
+        }
 
         ESP_ERROR_CHECK(esp_task_wdt_reset());
         ESP_LOGI(TAG, "Task reset");