basic working mdns configuration

src/main.cpp

@@ -7,6 +7,7 @@
 #include "bme280.h"
 #include "config.h"
 #include "time.h"
+#include "mdns.h"
 
 #ifndef SERIAL_BAUD
 #define SERIAL_BAUD 74880
@@ -62,6 +63,9 @@ void setup()
     // Start Filesystem
     SPIFFS.begin();
 
+    // Start mDNS
+    uweather_mdns_init();
+
     // Setup Web Server
     uweather_web_init();
     // if disabled and connected, shutdown web server
@@ -82,5 +86,6 @@ void loop()
     uweather_web_handle();
     uweather_update_handle();
     uweather_time_handle();
+    uweather_mdns_handle();
     delay(10);
 }

src/mdns.cpp

@@ -0,0 +1,41 @@
+#include <mdns.h>
+#include <ESP8266WiFi.h>
+#include <DNSServer.h>
+#include <ESP8266mDNS.h>
+#include <Arduino.h>
+#include "config.h"
+
+#define DNS_PORT 53
+
+DNSServer DNS;
+bool is_active = false;
+
+void uweather_mdns_init()
+{
+    // TODO: this should also handle re-inits after hostname has changed?
+    const char* configured_host = (const char*) Config._data.mdns_hostname;
+
+    // If a host is configured, start mDNS
+    is_active = false;
+    if (WiFi.isConnected() && configured_host != nullptr && configured_host[0] != '\0') {
+        if (MDNS.begin("weather", WiFi.localIP())) {
+            MDNS.addService("http", "tcp", 80);
+            is_active = true;
+            Serial.printf("Started mDNS responder for hostname %s.local\n", configured_host);
+        } else {
+            Serial.println("Error starting mDNS responder");
+        }
+    }
+
+    // TODO: only use this when using softAP
+    DNS.start(DNS_PORT, "*", WiFi.softAPIP());
+    
+}
+
+void uweather_mdns_handle()
+{
+    DNS.processNextRequest();  // TODO only when using softap
+    if (is_active) {
+        MDNS.update();
+    }
+}

src/mdns.h

@@ -0,0 +1,7 @@
+#ifndef _UWEATHER_MDNS_H_
+#define _UWEATHER_MDNS_H_
+
+void uweather_mdns_init();
+void uweather_mdns_handle();
+
+#endif /* End _UWEATHER_MDNS_H include guard */