Factored out MQTT stuff

2020-02-28 17:03:10 +01:00
parent 78863808d7
commit f19bc85a86
3 changed files with 282 additions and 76 deletions
--- a/include/MQTTHelper.h
+++ b/include/MQTTHelper.h
@@ -0,0 +1,113 @@
+#include <PubSubClient.h>
+#include <Arduino.h>
+#include <ESP8266WiFi.h>
+#include <ArduinoJson.h>
+
+class MQTTHelper {
+  private: 
+    String _group = "homedevice";
+    String _identifier = "garagesensor";
+    const char* _user = "homedevice";
+    const char* _password = "WNzAb4VazNFUPlpkn0ED";
+
+    WiFiClient _espClient;
+    PubSubClient _mqttClient;
+    String  _will_topic;
+    
+    void reconnect(int delayMillis = 5000);
+    bool connect();
+    void announce();
+    void callback(char* topic, byte* payload, unsigned int length);
+  public:
+    MQTTHelper() : _espClient(), _mqttClient(_espClient) {
+        auto deviceMac = WiFi.macAddress();
+        deviceMac.replace(":","");
+        _identifier = "etxean-"+deviceMac.substring(6);
+        _will_topic = getTopic("online");
+        _mqttClient.setCallback([this] (char* topic, byte* payload, unsigned int length) { this->callback(topic, payload, length); });
+    }
+
+    String getIdentifier() { return _identifier; }
+    
+    String getTopic(String sensor) {
+        return _group + "/" + _identifier + "/" + sensor;
+    }
+    
+    void Configure(IPAddress server, uint16 port) {
+        Serial.println("Configuring MQTT connection to: "+server.toString()+":"+String(port));
+        _mqttClient.setServer(server, port);
+        if (_mqttClient.connected()) {
+            connect();
+        }
+    }
+    
+    void loop() {
+        static unsigned long lastWill;
+        if (!_mqttClient.connected()) {
+            reconnect();
+        }
+        _mqttClient.loop();
+
+        auto now = millis();
+        if ((now - lastWill) > 1000)
+        {
+            lastWill = now;
+            _mqttClient.publish(_will_topic.c_str(), "true");
+        }
+    }
+
+    template<class T>
+    void publish(String sensor, T payload, bool retained = false) {
+        _mqttClient.publish(getTopic(sensor).c_str(), String(payload).c_str(), retained);
+    }
+};
+
+void MQTTHelper::callback(char* topic, byte* payload, unsigned int length) {
+    Serial.print("Message arrived:");
+    Serial.print(topic);
+    Serial.print(" = ");
+    for (unsigned int i=0;  i<length; i++) {
+        Serial.print((char)payload[i]);
+    }
+    Serial.println();
+}
+
+void MQTTHelper::reconnect(int delayMillis) {
+  // Loop until we're reconnected
+  while (!_mqttClient.connected()) {
+    Serial.print("Attempting MQTT connection...");
+    if (connect()) {
+        Serial.println("connected");
+    } else {
+        auto reconnectSeconds = (int)round(delayMillis/1000.0);
+        Serial.print("failed, rc=");
+        Serial.print(_mqttClient.state());
+        Serial.println(" try again in "+String(reconnectSeconds)+" seconds");
+        // Wait 5 seconds before retrying
+        delay(delayMillis);
+    }
+  }
+}
+
+void MQTTHelper::announce() {
+    DynamicJsonDocument doc(1024);
+    doc["id"] = _identifier;
+    doc["ip"] = WiFi.localIP().toString();
+    doc["mac"] = WiFi.macAddress();
+    String payload;
+    serializeJson(doc,payload);
+    publish("settings",payload);
+}
+
+bool MQTTHelper::connect() {
+    // If you do not want to use a username and password, change next line to
+    // if (_mqttClient.connect(_identifier.c_str()) {    
+    if (_mqttClient.connect(_identifier.c_str(), _user, _password, _will_topic.c_str(), 2, false, "false")) {
+        _mqttClient.subscribe((getTopic("settings")+"/get").c_str());
+        announce();
+        return true;
+    } else {
+        return false;
+    }
+}
+