Arduino MKR 1010 Wifi

The following code by blank-tree basically works with the Arduino MKR 1010 Wifi, but might stop working after a few hours (as the author reports).

#include <WiFiNINA.h>
#include <MQTT.h>

const char WIFI_SSID[] = "ssid"; // WiFI ssid
const char WIFI_PASS[] = "pass"; //WiFI password
const char mqttServer[] = "broker"; // broker, with shiftr.io it's "broker.shiftr.io"
const int mqttServerPort = 1883; // broker mqtt port
const char key[] = "key"; // broker key
const char secret[] = "secret"; // broker secret
const char device[] = "arduino"; // broker device identifier


int status = WL_IDLE_STATUS;
WiFiClient net;
MQTTClient client;

unsigned long lastMillis = 0;

void connect() {
  Serial.print("checking wifi...");
  while ( status != WL_CONNECTED) {
    status = WiFi.begin(WIFI_SSID, WIFI_PASS);
    Serial.print(".");
    delay(1000);
  }
  Serial.println("\nconnected to WiFi!\n");

  client.begin(mqttServer, mqttServerPort, net);

  Serial.println("connecting to broker...");
  while (!client.connect(device, key, secret)) {
    Serial.print(".");
    delay(1000);
  }

  Serial.println("Connected to MQTT");

  client.onMessage(messageReceived);

  client.subscribe("/hello");
  // client.unsubscribe("/hello");
}

void messageReceived(String &topic, String &payload) {
  Serial.println("incoming: " + topic + " - " + payload);
}

void setup() {
  Serial.begin(115200);
  connect();
}

void loop() {
  client.loop();
  // delay(1000); // helps eventually

  if (!net.connected()) {
    connect();
  }

  if (millis() - lastMillis > 1000) {
    lastMillis = millis();
    client.publish("/hello", "world");
    lastMillis = millis();
  }
}

Feel free to add your findings about using the MQTT library with the MKR 1010 Wifi in this issue: compatibility: ARDUINO MKR WIFI 1010 and WiFiNINA library.