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Merged
blazoncek merged 4 commits into from
Aug 2, 2025
Merged

Add mDNS support for MQTT server #4769

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79b3bc2
Add mDNS support for MQTT server
blazoncek Jul 12, 2025
24f2306
Strip .local from mDNS resolution
blazoncek Jul 15, 2025
07e303b
Remove anything behind .local and ignore case
blazoncek Jul 15, 2025
ecc3eae
Revert status message change
blazoncek Jul 16, 2025
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56 changes: 34 additions & 22 deletions wled00/mqtt.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -11,6 +11,11 @@
#warning "MQTT topics length > 32 is not recommended for compatibility with usermods!"
#endif

static const char* sTopicFormat PROGMEM = "%.*s/%s";

// parse payload for brightness, ON/OFF or toggle
// briLast is used to remember last brightness value in case of ON/OFF or toggle
// bri is set to 0 if payload is "0" or "OFF" or "false"
static void parseMQTTBriPayload(char* payload)
{
if (strstr(payload, "ON") || strstr(payload, "on") || strstr(payload, "true")) {bri = briLast; stateUpdated(CALL_MODE_DIRECT_CHANGE);}
Expand All @@ -30,22 +35,18 @@ static void onMqttConnect(bool sessionPresent)
char subuf[MQTT_MAX_TOPIC_LEN + 9];

if (mqttDeviceTopic[0] != 0) {
strlcpy(subuf, mqttDeviceTopic, MQTT_MAX_TOPIC_LEN + 1);
mqtt->subscribe(subuf, 0);
strcat_P(subuf, PSTR("/col"));
mqtt->subscribe(mqttDeviceTopic, 0);
snprintf_P(subuf, sizeof(subuf)-1, sTopicFormat, MQTT_MAX_TOPIC_LEN, mqttDeviceTopic, "col");
mqtt->subscribe(subuf, 0);
strlcpy(subuf, mqttDeviceTopic, MQTT_MAX_TOPIC_LEN + 1);
strcat_P(subuf, PSTR("/api"));
snprintf_P(subuf, sizeof(subuf)-1, sTopicFormat, MQTT_MAX_TOPIC_LEN, mqttDeviceTopic, "api");
mqtt->subscribe(subuf, 0);
}

if (mqttGroupTopic[0] != 0) {
strlcpy(subuf, mqttGroupTopic, MQTT_MAX_TOPIC_LEN + 1);
mqtt->subscribe(mqttGroupTopic, 0);
snprintf_P(subuf, sizeof(subuf)-1, sTopicFormat, MQTT_MAX_TOPIC_LEN, mqttGroupTopic, "col");
mqtt->subscribe(subuf, 0);
strcat_P(subuf, PSTR("/col"));
mqtt->subscribe(subuf, 0);
strlcpy(subuf, mqttGroupTopic, MQTT_MAX_TOPIC_LEN + 1);
strcat_P(subuf, PSTR("/api"));
snprintf_P(subuf, sizeof(subuf)-1, sTopicFormat, MQTT_MAX_TOPIC_LEN, mqttGroupTopic, "api");
mqtt->subscribe(subuf, 0);
}

Expand All @@ -54,8 +55,7 @@ static void onMqttConnect(bool sessionPresent)
DEBUG_PRINTLN(F("MQTT ready"));

#ifndef USERMOD_SMARTNEST
strlcpy(subuf, mqttDeviceTopic, MQTT_MAX_TOPIC_LEN + 1);
strcat_P(subuf, PSTR("/status"));
snprintf_P(subuf, sizeof(subuf)-1, sTopicFormat, MQTT_MAX_TOPIC_LEN, mqttDeviceTopic, "status");
mqtt->publish(subuf, 0, true, "online"); // retain message for a LWT
#endif

Expand Down Expand Up @@ -136,7 +136,7 @@ static void onMqttMessage(char* topic, char* payload, AsyncMqttClientMessageProp
}

// Print adapter for flat buffers
namespace {
namespace {
class bufferPrint : public Print {
char* _buf;
size_t _size, _offset;
Expand Down Expand Up @@ -172,21 +172,21 @@ void publishMqtt()
char subuf[MQTT_MAX_TOPIC_LEN + 16];

sprintf_P(s, PSTR("%u"), bri);
strlcpy(subuf, mqttDeviceTopic, MQTT_MAX_TOPIC_LEN + 1);
strcat_P(subuf, PSTR("/g"));
snprintf_P(subuf, sizeof(subuf)-1, sTopicFormat, MQTT_MAX_TOPIC_LEN, mqttDeviceTopic, "g");
mqtt->publish(subuf, 0, retainMqttMsg, s); // optionally retain message (#2263)

sprintf_P(s, PSTR("#%06X"), (colPri[3] << 24) | (colPri[0] << 16) | (colPri[1] << 8) | (colPri[2]));
strlcpy(subuf, mqttDeviceTopic, MQTT_MAX_TOPIC_LEN + 1);
strcat_P(subuf, PSTR("/c"));
snprintf_P(subuf, sizeof(subuf)-1, sTopicFormat, MQTT_MAX_TOPIC_LEN, mqttDeviceTopic, "c");
mqtt->publish(subuf, 0, retainMqttMsg, s); // optionally retain message (#2263)

snprintf_P(subuf, sizeof(subuf)-1, sTopicFormat, MQTT_MAX_TOPIC_LEN, mqttDeviceTopic, "status");
mqtt->publish(subuf, 0, true, "online"); // retain message for a LWT

// TODO: use a DynamicBufferList. Requires a list-read-capable MQTT client API.
DynamicBuffer buf(1024);
bufferPrint pbuf(buf.data(), buf.size());
XML_response(pbuf);
strlcpy(subuf, mqttDeviceTopic, MQTT_MAX_TOPIC_LEN + 1);
strcat_P(subuf, PSTR("/v"));
snprintf_P(subuf, sizeof(subuf)-1, sTopicFormat, MQTT_MAX_TOPIC_LEN, mqttDeviceTopic, "v");
mqtt->publish(subuf, 0, retainMqttMsg, buf.data(), pbuf.size()); // optionally retain message (#2263)
#endif
}
Expand All @@ -213,14 +213,26 @@ bool initMqtt()
{
mqtt->setServer(mqttIP, mqttPort);
} else {
mqtt->setServer(mqttServer, mqttPort);
#ifdef ARDUINO_ARCH_ESP32
String mqttMDNS = mqttServer;
mqttMDNS.toLowerCase(); // make sure we have a lowercase hostname
int pos = mqttMDNS.indexOf(F(".local"));
if (pos > 0) mqttMDNS.remove(pos); // remove .local domain if present (and anything following it)
if (strlen(cmDNS) > 0 && mqttMDNS.length() > 0 && mqttMDNS.indexOf('.') < 0) { // if mDNS is enabled and server does not have domain
mqttIP = MDNS.queryHost(mqttMDNS.c_str());
if (mqttIP != IPAddress()) // if MDNS resolved the hostname
mqtt->setServer(mqttIP, mqttPort);
else
mqtt->setServer(mqttServer, mqttPort);
} else
#endif
mqtt->setServer(mqttServer, mqttPort);
}
mqtt->setClientId(mqttClientID);
if (mqttUser[0] && mqttPass[0]) mqtt->setCredentials(mqttUser, mqttPass);

#ifndef USERMOD_SMARTNEST
strlcpy(mqttStatusTopic, mqttDeviceTopic, MQTT_MAX_TOPIC_LEN + 1);
strcat_P(mqttStatusTopic, PSTR("/status"));
snprintf_P(mqttStatusTopic, sizeof(mqttStatusTopic)-1, sTopicFormat, MQTT_MAX_TOPIC_LEN, mqttDeviceTopic, "status");
mqtt->setWill(mqttStatusTopic, 0, true, "offline"); // LWT message
#endif
mqtt->setKeepAlive(MQTT_KEEP_ALIVE_TIME);
Expand Down