MQTTClient_Basic.ino

/****************************************************************************************************************************
  MQTTClient_Basic.ino - Dead simple MQTT Client for Ethernet shields

  For Ethernet shields using ESP32_W5500 (ESP32 + W5500)

  WebServer_ESP32_W5500 is a library for the ESP32 with Ethernet W5500 to run WebServer

  Based on and modified from ESP32-IDF https://github.com/espressif/esp-idf
  Built by Khoi Hoang https://github.com/khoih-prog/WebServer_ESP32_W5500
  Licensed under GPLv3 license
 *****************************************************************************************************************************/

/*
  Basic MQTT example (without SSL!) with Authentication
  This sketch demonstrates the basic capabilities of the library.
  It connects to an MQTT server then:
  - providing username and password
  - publishes "hello world" to the topic "outTopic"
  - subscribes to the topic "inTopic", printing out any messages
    it receives. NB - it assumes the received payloads are strings not binary

  It will reconnect to the server if the connection is lost using a blocking
  reconnect function. See the 'mqtt_reconnect_nonblocking' example for how to
  achieve the same result without blocking the main loop.
*/

#if !( defined(ESP32) )
  #error This code is designed for (ESP32 + W5500) to run on ESP32 platform! Please check your Tools->Board setting.
#endif

#define DEBUG_ETHERNET_WEBSERVER_PORT       Serial

// Debug Level from 0 to 4
#define _ETHERNET_WEBSERVER_LOGLEVEL_       3

//////////////////////////////////////////////////////////

// Optional values to override default settings
// Don't change unless you know what you're doing
//#define ETH_SPI_HOST        SPI3_HOST
//#define SPI_CLOCK_MHZ       25

// Must connect INT to GPIOxx or not working
//#define INT_GPIO            4

//#define MISO_GPIO           19
//#define MOSI_GPIO           23
//#define SCK_GPIO            18
//#define CS_GPIO             5

//////////////////////////////////////////////////////////

#include <WebServer_ESP32_W5500.h>

WebServer server(80);

// Enter a MAC address and IP address for your controller below.
#define NUMBER_OF_MAC      20

byte mac[][NUMBER_OF_MAC] =
{
  { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0x01 },
  { 0xDE, 0xAD, 0xBE, 0xEF, 0xBE, 0x02 },
  { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0x03 },
  { 0xDE, 0xAD, 0xBE, 0xEF, 0xBE, 0x04 },
  { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0x05 },
  { 0xDE, 0xAD, 0xBE, 0xEF, 0xBE, 0x06 },
  { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0x07 },
  { 0xDE, 0xAD, 0xBE, 0xEF, 0xBE, 0x08 },
  { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0x09 },
  { 0xDE, 0xAD, 0xBE, 0xEF, 0xBE, 0x0A },
  { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0x0B },
  { 0xDE, 0xAD, 0xBE, 0xEF, 0xBE, 0x0C },
  { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0x0D },
  { 0xDE, 0xAD, 0xBE, 0xEF, 0xBE, 0x0E },
  { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0x0F },
  { 0xDE, 0xAD, 0xBE, 0xEF, 0xBE, 0x10 },
  { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0x11 },
  { 0xDE, 0xAD, 0xBE, 0xEF, 0xBE, 0x12 },
  { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0x13 },
  { 0xDE, 0xAD, 0xBE, 0xEF, 0xBE, 0x14 },
};

// Select the IP address according to your local network
IPAddress myIP(192, 168, 2, 232);
IPAddress myGW(192, 168, 2, 1);
IPAddress mySN(255, 255, 255, 0);

// Google DNS Server IP
IPAddress myDNS(8, 8, 8, 8);

#include <PubSubClient.h>

// Update these with values suitable for your network.
//const char* mqttServer = "broker.example";        // Broker address
const char* mqttServer = "broker.emqx.io";        // Broker address
//const char* mqttServer = "broker.shiftr.io";        // Broker address

const char *ID        = "MQTTClient_SSL-Client";  // Name of our device, must be unique
const char *TOPIC     = "MQTT_Pub";               // Topic to subscribe to
const char *subTopic  = "MQTT_Sub";               // Topic to subscribe to

//IPAddress mqttServer(172, 16, 0, 2);

void 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();
}

WiFiClient    ethClient;
PubSubClient    client(mqttServer, 1883, callback, ethClient);

void reconnect()
{
  // Loop until we're reconnected
  while (!client.connected())
  {
    //Serial.print("Attempting MQTT connection to ");
    //Serial.print(mqttServer);

    // Attempt to connect
    if (client.connect(ID, "try", "try"))
    {
      //Serial.println("...connected");

      // Once connected, publish an announcement...
      String data = "Hello from MQTTClient_SSL on " + String(BOARD_NAME);

      client.publish(TOPIC, data.c_str());

      //Serial.println("Published connection message successfully!");
      //Serial.print("Subscribed to: ");
      //Serial.println(subTopic);

      // This is a workaround to address https://github.com/OPEnSLab-OSU/SSLClient/issues/9
      //ethClientSSL.flush();
      // ... and resubscribe
      client.subscribe(subTopic);
      // for loopback testing
      client.subscribe(TOPIC);
      // This is a workaround to address https://github.com/OPEnSLab-OSU/SSLClient/issues/9
      //ethClientSSL.flush();
    }
    else
    {
      Serial.print("...failed, rc=");
      Serial.print(client.state());
      Serial.println(" try again in 5 seconds");

      // Wait 5 seconds before retrying
      delay(5000);
    }
  }
}

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

  while (!Serial && (millis() < 5000));

  Serial.print(F("\nStart MQTTClient_Basic on "));
  Serial.print(ARDUINO_BOARD);
  Serial.print(F(" with "));
  Serial.println(SHIELD_TYPE);
  Serial.println(WEBSERVER_ESP32_W5500_VERSION);

  ET_LOGWARN(F("Default SPI pinout:"));
  ET_LOGWARN1(F("SPI_HOST:"), ETH_SPI_HOST);
  ET_LOGWARN1(F("MOSI:"), MOSI_GPIO);
  ET_LOGWARN1(F("MISO:"), MISO_GPIO);
  ET_LOGWARN1(F("SCK:"),  SCK_GPIO);
  ET_LOGWARN1(F("CS:"),   CS_GPIO);
  ET_LOGWARN1(F("INT:"),  INT_GPIO);
  ET_LOGWARN1(F("SPI Clock (MHz):"), SPI_CLOCK_MHZ);
  ET_LOGWARN(F("========================="));

  ///////////////////////////////////

  // To be called before ETH.begin()
  ESP32_W5500_onEvent();

  // start the ethernet connection and the server:
  // Use DHCP dynamic IP and random mac
  //bool begin(int MISO_GPIO, int MOSI_GPIO, int SCLK_GPIO, int CS_GPIO, int INT_GPIO, int SPI_CLOCK_MHZ,
  //           int SPI_HOST, uint8_t *W6100_Mac = W6100_Default_Mac);
  ETH.begin( MISO_GPIO, MOSI_GPIO, SCK_GPIO, CS_GPIO, INT_GPIO, SPI_CLOCK_MHZ, ETH_SPI_HOST );
  //ETH.begin( MISO_GPIO, MOSI_GPIO, SCK_GPIO, CS_GPIO, INT_GPIO, SPI_CLOCK_MHZ, ETH_SPI_HOST, mac[millis() % NUMBER_OF_MAC] );

  // Static IP, leave without this line to get IP via DHCP
  //bool config(IPAddress local_ip, IPAddress gateway, IPAddress subnet, IPAddress dns1 = 0, IPAddress dns2 = 0);
  //ETH.config(myIP, myGW, mySN, myDNS);

  ESP32_W5500_waitForConnect();

  ///////////////////////////////////

  client.setServer(mqttServer, 1883);
  client.setCallback(callback);

  // Allow the hardware to sort itself out
  delay(1500);
}

#define MQTT_PUBLISH_INTERVAL_MS       5000L

String data         = "Hello from MQTTClient_Basic on " + String(ARDUINO_BOARD) + " with " + String(SHIELD_TYPE);
const char *pubData = data.c_str();

unsigned long lastMsg = 0;

void loop()
{
  static unsigned long now;

  if (!client.connected())
  {
    reconnect();
  }

  // Sending Data
  now = millis();

  if (now - lastMsg > MQTT_PUBLISH_INTERVAL_MS)
  {
    lastMsg = now;

    if (!client.publish(TOPIC, pubData))
    {
      Serial.println("Message failed to send.");
    }

    Serial.print("Message Send : " + String(TOPIC) + " => ");
    Serial.println(data);
  }

  client.loop();
}