MQTT sensors handling of publishing NaN values (#7768)

Co-authored-by: Jesse Hills <3060199+jesserockz@users.noreply.github.com>

esphome/components/mqtt/__init__.py

@@ -49,6 +49,7 @@ from esphome.const import (
     CONF_USE_ABBREVIATIONS,
     CONF_USERNAME,
     CONF_WILL_MESSAGE,
+    CONF_PUBLISH_NAN_AS_NONE,
     PLATFORM_BK72XX,
     PLATFORM_ESP32,
     PLATFORM_ESP8266,
@@ -296,6 +297,7 @@ CONFIG_SCHEMA = cv.All(
                     cv.Optional(CONF_QOS, default=0): cv.mqtt_qos,
                 }
             ),
+            cv.Optional(CONF_PUBLISH_NAN_AS_NONE, default=False): cv.boolean,
         }
     ),
     validate_config,
@@ -449,6 +451,8 @@ async def to_code(config):
         trigger = cg.new_Pvariable(conf[CONF_TRIGGER_ID], var)
         await automation.build_automation(trigger, [], conf)
 
+    cg.add(var.set_publish_nan_as_none(config[CONF_PUBLISH_NAN_AS_NONE]))
+
 
 MQTT_PUBLISH_ACTION_SCHEMA = cv.Schema(
     {

esphome/components/mqtt/mqtt_client.cpp

@@ -608,6 +608,10 @@ void MQTTClientComponent::set_log_message_template(MQTTMessage &&message) { this
 const MQTTDiscoveryInfo &MQTTClientComponent::get_discovery_info() const { return this->discovery_info_; }
 void MQTTClientComponent::set_topic_prefix(const std::string &topic_prefix) { this->topic_prefix_ = topic_prefix; }
 const std::string &MQTTClientComponent::get_topic_prefix() const { return this->topic_prefix_; }
+void MQTTClientComponent::set_publish_nan_as_none(bool publish_nan_as_none) {
+  this->publish_nan_as_none_ = publish_nan_as_none;
+}
+bool MQTTClientComponent::is_publish_nan_as_none() const { return this->publish_nan_as_none_; }
 void MQTTClientComponent::disable_birth_message() {
   this->birth_message_.topic = "";
   this->recalculate_availability_();

esphome/components/mqtt/mqtt_client.h

@@ -263,6 +263,10 @@ class MQTTClientComponent : public Component {
   void set_on_connect(mqtt_on_connect_callback_t &&callback);
   void set_on_disconnect(mqtt_on_disconnect_callback_t &&callback);
 
+  // Publish None state instead of NaN for Home Assistant
+  void set_publish_nan_as_none(bool publish_nan_as_none);
+  bool is_publish_nan_as_none() const;
+
  protected:
   void send_device_info_();
 
@@ -328,6 +332,8 @@ class MQTTClientComponent : public Component {
   uint32_t connect_begin_;
   uint32_t last_connected_{0};
   optional<MQTTClientDisconnectReason> disconnect_reason_{};
+
+  bool publish_nan_as_none_{false};
 };
 
 extern MQTTClientComponent *global_mqtt_client;  // NOLINT(cppcoreguidelines-avoid-non-const-global-variables)

esphome/components/mqtt/mqtt_sensor.cpp

@@ -69,6 +69,8 @@ bool MQTTSensorComponent::send_initial_state() {
   }
 }
 bool MQTTSensorComponent::publish_state(float value) {
+  if (mqtt::global_mqtt_client->is_publish_nan_as_none() && std::isnan(value))
+    return this->publish(this->get_state_topic_(), "None");
   int8_t accuracy = this->sensor_->get_accuracy_decimals();
   return this->publish(this->get_state_topic_(), value_accuracy_to_string(value, accuracy));
 }

esphome/const.py

@@ -692,6 +692,7 @@ CONF_PRIORITY = "priority"
 CONF_PROJECT = "project"
 CONF_PROTOCOL = "protocol"
 CONF_PUBLISH_INITIAL_STATE = "publish_initial_state"
+CONF_PUBLISH_NAN_AS_NONE = "publish_nan_as_none"
 CONF_PULL_MODE = "pull_mode"
 CONF_PULLDOWN = "pulldown"
 CONF_PULLUP = "pullup"

tests/components/mqtt/common.yaml

@@ -60,6 +60,7 @@ mqtt:
     - mqtt.publish:
         topic: some/topic
         payload: Good-bye
+  publish_nan_as_none: false
 
 binary_sensor:
   - platform: template