[mdns] Support templatable config options for MDNS extra services (#8606)

esphome/components/mdns/__init__.py

@@ -35,8 +35,8 @@ SERVICE_SCHEMA = cv.Schema(
     {
         cv.Required(CONF_SERVICE): cv.string,
         cv.Required(CONF_PROTOCOL): cv.string,
-        cv.Optional(CONF_PORT, default=0): cv.Any(0, cv.port),
+        cv.Optional(CONF_PORT, default=0): cv.templatable(cv.Any(0, cv.port)),
-        cv.Optional(CONF_TXT, default={}): {cv.string: cv.string},
+        cv.Optional(CONF_TXT, default={}): {cv.string: cv.templatable(cv.string)},
     }
 )
 
@@ -102,12 +102,18 @@ async def to_code(config):
 
     for service in config[CONF_SERVICES]:
         txt = [
-            mdns_txt_record(txt_key, txt_value)
+            cg.StructInitializer(
+                MDNSTXTRecord,
+                ("key", txt_key),
+                ("value", await cg.templatable(txt_value, [], cg.std_string)),
+            )
             for txt_key, txt_value in service[CONF_TXT].items()
         ]
-
         exp = mdns_service(
-            service[CONF_SERVICE], service[CONF_PROTOCOL], service[CONF_PORT], txt
+            service[CONF_SERVICE],
+            service[CONF_PROTOCOL],
+            await cg.templatable(service[CONF_PORT], [], cg.uint16),
+            txt,
         )
 
         cg.add(var.add_extra_service(exp))

esphome/components/mdns/mdns_component.cpp

@@ -121,9 +121,11 @@ void MDNSComponent::dump_config() {
   ESP_LOGCONFIG(TAG, "  Hostname: %s", this->hostname_.c_str());
   ESP_LOGV(TAG, "  Services:");
   for (const auto &service : this->services_) {
-    ESP_LOGV(TAG, "  - %s, %s, %d", service.service_type.c_str(), service.proto.c_str(), service.port);
+    ESP_LOGV(TAG, "  - %s, %s, %d", service.service_type.c_str(), service.proto.c_str(),
+             const_cast<TemplatableValue<uint16_t> &>(service.port).value());
     for (const auto &record : service.txt_records) {
-      ESP_LOGV(TAG, "    TXT: %s = %s", record.key.c_str(), record.value.c_str());
+      ESP_LOGV(TAG, "    TXT: %s = %s", record.key.c_str(),
+               const_cast<TemplatableValue<std::string> &>(record.value).value().c_str());
     }
   }
 }

esphome/components/mdns/mdns_component.h

@@ -3,6 +3,7 @@
 #ifdef USE_MDNS
 #include <string>
 #include <vector>
+#include "esphome/core/automation.h"
 #include "esphome/core/component.h"
 
 namespace esphome {
@@ -10,7 +11,7 @@ namespace mdns {
 
 struct MDNSTXTRecord {
   std::string key;
-  std::string value;
+  TemplatableValue<std::string> value;
 };
 
 struct MDNSService {
@@ -20,7 +21,7 @@ struct MDNSService {
   // second label indicating protocol _including_ underscore character prefix
   // as defined in RFC6763 Section 7, like "_tcp" or "_udp"
   std::string proto;
-  uint16_t port;
+  TemplatableValue<uint16_t> port;
   std::vector<MDNSTXTRecord> txt_records;
 };
 

esphome/components/mdns/mdns_esp32.cpp

@@ -31,11 +31,12 @@ void MDNSComponent::setup() {
       mdns_txt_item_t it{};
       // dup strings to ensure the pointer is valid even after the record loop
       it.key = strdup(record.key.c_str());
-      it.value = strdup(record.value.c_str());
+      it.value = strdup(const_cast<TemplatableValue<std::string> &>(record.value).value().c_str());
       txt_records.push_back(it);
     }
-    err = mdns_service_add(nullptr, service.service_type.c_str(), service.proto.c_str(), service.port,
+    uint16_t port = const_cast<TemplatableValue<uint16_t> &>(service.port).value();
-                           txt_records.data(), txt_records.size());
+    err = mdns_service_add(nullptr, service.service_type.c_str(), service.proto.c_str(), port, txt_records.data(),
+                           txt_records.size());
 
     // free records
     for (const auto &it : txt_records) {

esphome/components/mdns/mdns_esp8266.cpp

@@ -29,9 +29,11 @@ void MDNSComponent::setup() {
     while (*service_type == '_') {
       service_type++;
     }
-    MDNS.addService(service_type, proto, service.port);
+    uint16_t port = const_cast<TemplatableValue<uint16_t> &>(service.port).value();
+    MDNS.addService(service_type, proto, port);
     for (const auto &record : service.txt_records) {
-      MDNS.addServiceTxt(service_type, proto, record.key.c_str(), record.value.c_str());
+      MDNS.addServiceTxt(service_type, proto, record.key.c_str(),
+                         const_cast<TemplatableValue<std::string> &>(record.value).value().c_str());
     }
   }
 }

esphome/components/mdns/mdns_libretiny.cpp

@@ -29,9 +29,11 @@ void MDNSComponent::setup() {
     while (*service_type == '_') {
       service_type++;
     }
-    MDNS.addService(service_type, proto, service.port);
+    uint16_t port_ = const_cast<TemplatableValue<uint16_t> &>(service.port).value();
+    MDNS.addService(service_type, proto, port_);
     for (const auto &record : service.txt_records) {
-      MDNS.addServiceTxt(service_type, proto, record.key.c_str(), record.value.c_str());
+      MDNS.addServiceTxt(service_type, proto, record.key.c_str(),
+                         const_cast<TemplatableValue<std::string> &>(record.value).value().c_str());
     }
   }
 }

esphome/components/mdns/mdns_rp2040.cpp

@@ -29,9 +29,11 @@ void MDNSComponent::setup() {
     while (*service_type == '_') {
       service_type++;
     }
-    MDNS.addService(service_type, proto, service.port);
+    uint16_t port = const_cast<TemplatableValue<uint16_t> &>(service.port).value();
+    MDNS.addService(service_type, proto, port);
     for (const auto &record : service.txt_records) {
-      MDNS.addServiceTxt(service_type, proto, record.key.c_str(), record.value.c_str());
+      MDNS.addServiceTxt(service_type, proto, record.key.c_str(),
+                         const_cast<TemplatableValue<std::string> &>(record.value).value().c_str());
     }
   }
 }

esphome/core/automation.h

@@ -1,10 +1,11 @@
 #pragma once
 
-#include <vector>
 #include "esphome/core/component.h"
-#include "esphome/core/helpers.h"
 #include "esphome/core/defines.h"
+#include "esphome/core/helpers.h"
 #include "esphome/core/preferences.h"
+#include <utility>
+#include <vector>
 
 namespace esphome {
 
@@ -27,7 +28,7 @@ template<typename T, typename... X> class TemplatableValue {
   TemplatableValue() : type_(NONE) {}
 
   template<typename F, enable_if_t<!is_invocable<F, X...>::value, int> = 0>
-  TemplatableValue(F value) : type_(VALUE), value_(value) {}
+  TemplatableValue(F value) : type_(VALUE), value_(std::move(value)) {}
 
   template<typename F, enable_if_t<is_invocable<F, X...>::value, int> = 0>
   TemplatableValue(F f) : type_(LAMBDA), f_(f) {}

tests/components/mdns/common-enabled.yaml

@@ -4,3 +4,10 @@ wifi:
 
 mdns:
   disabled: false
+  services:
+    - service: _test_service
+      protocol: _tcp
+      port: 8888
+      txt:
+        static_string: Anything
+        templated_string: !lambda return "Something else";