110 lines
3.4 KiB
C++
110 lines
3.4 KiB
C++
/*
|
|
* KiteLib ESP8266 MQTT Subscribe Example
|
|
*
|
|
* This example subscribes to MQTT topic using ESP8266 WiFi module.
|
|
*
|
|
* The messages are pulled from https://shiftr.io/try. You can use this namespace
|
|
* for testing purposes, but remember that it is publicly accessible!
|
|
*
|
|
* IMPORTANT: Before uploading this example, make sure that the ESP8266 module is running
|
|
* AT firmware (can be found in the /extras folder of the library)!
|
|
*/
|
|
|
|
// include the library
|
|
#include <KiteLib.h>
|
|
|
|
// ESP8266 module is in slot A on the shield
|
|
ESP8266 wifi = Kite.ModuleA;
|
|
|
|
// create MQTT client instance using the wifi module
|
|
MQTTClient mqtt(&wifi);
|
|
|
|
void setup() {
|
|
Serial.begin(9600);
|
|
|
|
// initialize ESP8266 with baudrate 9600
|
|
Serial.print(F("[ESP8266] Initializing ... "));
|
|
byte state = wifi.begin(9600);
|
|
if(state == ERR_NONE) {
|
|
Serial.println(F("success!"));
|
|
} else {
|
|
Serial.print(F("failed, code 0x"));
|
|
Serial.println(state, HEX);
|
|
while(true);
|
|
}
|
|
|
|
// join AP named "SSID" using the password "password"
|
|
Serial.print(F("[ESP8266] Joining AP ... "));
|
|
state = wifi.join("SSID", "password");
|
|
if(state == ERR_NONE) {
|
|
Serial.println(F("success!"));
|
|
} else {
|
|
Serial.print(F("failed, code 0x"));
|
|
Serial.println(state, HEX);
|
|
while(true);
|
|
}
|
|
|
|
// connect to MQTT broker using client ID "arduino", username "try" and password "try"
|
|
Serial.print(F("[ESP8266] Connecting to MQTT broker ... "));
|
|
state = mqtt.connect("broker.shiftr.io", "arduino", "try", "try");
|
|
if(state == ERR_NONE) {
|
|
Serial.println(F("success!"));
|
|
} else {
|
|
Serial.print(F("failed, code 0x"));
|
|
Serial.println(state, HEX);
|
|
while(true);
|
|
}
|
|
|
|
// subscribe to the topic "hello"
|
|
// after calling this method, server will send PUBLISH packets
|
|
// to this client each time a new message was published at the topic
|
|
Serial.print(F("[ESP8266] Subscribing to MQTT topic ... "));
|
|
state = wifi.subscribe("hello");
|
|
if(state == ERR_NONE) {
|
|
Serial.println(F("success!"));
|
|
} else {
|
|
Serial.print(F("failed, code 0x"));
|
|
Serial.println(state, HEX);
|
|
}
|
|
|
|
// unsubscribe from topic "hello"
|
|
// after calling this method, server will stop sending PUBLISH packets
|
|
Serial.print(F("[ESP8266] Unsubscribing from MQTT topic ... "));
|
|
state = wifi.unsubscribe("hello");
|
|
if(state == ERR_NONE) {
|
|
Serial.println(F("success!"));
|
|
} else {
|
|
Serial.print(F("failed, code 0x"));
|
|
Serial.println(state, HEX);
|
|
}
|
|
}
|
|
|
|
// create a function that will be called when a new PUBLISH packet
|
|
// arrives from the server
|
|
//
|
|
// IMPORTANT: This function MUST have two C-strings as arguments!
|
|
void onPublish(const char* topic, const char* message) {
|
|
Serial.println("[ESP8266] Received packet from MQTT server: ");
|
|
Serial.print("[ESP8266] Topic:\t");
|
|
Serial.println(topic);
|
|
Serial.print("[ESP8266] Message:\t");
|
|
Serial.println(message);
|
|
}
|
|
|
|
void loop() {
|
|
// check for new MQTT packets from server each time the loop() runs
|
|
// this will also send a PING packet, restarting the keep alive timer
|
|
byte state = wifi.check(onPublish);
|
|
Serial.print("[ESP8266] MQTT check ");
|
|
if(state == ERR_NONE) {
|
|
Serial.println(F("success!"));
|
|
} else {
|
|
Serial.print(F("failed, code 0x"));
|
|
Serial.println(state, HEX);
|
|
}
|
|
|
|
// the rest of your loop() code goes here
|
|
// make sure that the maximum time the loop() runs is less than 1.5x keep alive,
|
|
// otherwise the server will close the network connection
|
|
}
|
|
|