Initial commit, getting all the stuff from PlatformIO

.pio/libdeps/esp32dev/PicoMQTT/examples/server_local_pubsub/server_local_pubsub.ino

@@ -0,0 +1,52 @@
+#include <PicoMQTT.h>
+
+#if __has_include("config.h")
+#include "config.h"
+#endif
+
+#ifndef WIFI_SSID
+#define WIFI_SSID "WiFi SSID"
+#endif
+
+#ifndef WIFI_PASSWORD
+#define WIFI_PASSWORD "password"
+#endif
+
+PicoMQTT::Server mqtt;
+
+unsigned long last_publish_time = 0;
+int greeting_number = 1;
+
+void setup() {
+    // Setup serial
+    Serial.begin(115200);
+
+    // Connect to WiFi
+    Serial.printf("Connecting to WiFi %s\n", WIFI_SSID);
+    WiFi.mode(WIFI_STA);
+    WiFi.begin(WIFI_SSID, WIFI_PASSWORD);
+    while (WiFi.status() != WL_CONNECTED) { delay(1000); }
+    Serial.printf("WiFi connected, IP: %s\n", WiFi.localIP().toString().c_str());
+
+    // Subscribe to a topic and attach a callback
+    mqtt.subscribe("#", [](const char * topic, const char * payload) {
+        // payload might be binary, but PicoMQTT guarantees that it's zero-terminated
+        Serial.printf("Received message in topic '%s': %s\n", topic, payload);
+    });
+
+    mqtt.begin();
+}
+
+void loop() {
+    mqtt.loop();
+
+    // Publish a greeting message every 3 seconds.
+    if (millis() - last_publish_time >= 3000) {
+        // We're publishing to a topic, which we're subscribed too, but these message will *not* be delivered locally.
+        String topic = "picomqtt/esp-" + WiFi.macAddress();
+        String message = "Hello #" + String(greeting_number++);
+        Serial.printf("Publishing message in topic '%s': %s\n", topic.c_str(), message.c_str());
+        mqtt.publish(topic, message);
+        last_publish_time = millis();
+    }
+}