#include <mqtt_sensor.h>

Inheritance diagram for esphome::mqtt::MQTTSensorComponent:

Public Member Functions
	MQTTSensorComponent (sensor::Sensor *sensor)
	Construct this MQTTSensorComponent instance with the provided friendly_name and sensor.

void	set_expire_after (uint32_t expire_after)
	Setup an expiry, 0 disables it.

void	disable_expire_after ()
	Disable Home Assistant value expiry.

void	send_discovery (JsonObject root, mqtt::SendDiscoveryConfig &config) override

void	setup () override
	Override setup.

void	dump_config () override

uint32_t	get_expire_after () const
	Get the expire_after in milliseconds used for Home Assistant discovery, first checks override.

bool	publish_state (float value)

bool	send_initial_state () override

Public Member Functions inherited from esphome::mqtt::MQTTComponent
	MQTTComponent ()
	Constructs a MQTTComponent.

void	call_setup () override
	Override setup_ so that we can call send_discovery() when needed.

bool	is_internal () const
	Returns cached is_internal result (computed once during setup).

void	set_qos (uint8_t qos)
	Set QOS for state messages.

uint8_t	get_qos () const

void	set_retain (bool retain)
	Set whether state message should be retained.

bool	get_retain () const

void	disable_discovery ()
	Disable discovery. Sets friendly name to "".

bool	is_discovery_enabled () const

void	set_subscribe_qos (uint8_t qos)
	Set the QOS for subscribe messages (used in discovery).

template<typename T >
void	set_custom_state_topic (T &&custom_state_topic)
	Set a custom state topic. Do not set for default behavior.

template<typename T >
void	set_custom_command_topic (T &&custom_command_topic)

void	set_command_retain (bool command_retain)
	Set whether command message should be retained.

float	get_setup_priority () const override
	MQTT_COMPONENT setup priority.

void	set_availability (std::string topic, std::string payload_available, std::string payload_not_available)
	Set the Home Assistant availability data.

void	disable_availability ()

void	schedule_resend_state ()
	Internal method for the MQTT client base to schedule a resend of the state on reconnect.

void	process_resend ()
	Process pending resend if needed (called by MQTTClientComponent)

bool	publish (const std::string &topic, const std::string &payload)
	Send a MQTT message.

bool	publish (const std::string &topic, const char *payload, size_t payload_length)
	Send a MQTT message.

bool	publish (const std::string &topic, const char *payload)
	Send a MQTT message.

bool	publish (const char topic, const char payload, size_t payload_length)
	Send a MQTT message (no heap allocation for topic).

bool	publish (StringRef topic, const char *payload, size_t payload_length)
	Send a MQTT message (no heap allocation for topic).

bool	publish (const char topic, const char payload)
	Send a MQTT message (no heap allocation for topic).

bool	publish (StringRef topic, const char *payload)
	Send a MQTT message (no heap allocation for topic).

bool	publish (const std::string &topic, ProgmemStr payload)
	Send a MQTT message with a PROGMEM string payload.

bool	publish (const char *topic, ProgmemStr payload)
	Send a MQTT message with a PROGMEM string payload (no heap allocation for topic).

bool	publish (StringRef topic, ProgmemStr payload)
	Send a MQTT message with a PROGMEM string payload (no heap allocation for topic).

bool	publish_json (const std::string &topic, const json::json_build_t &f)
	Construct and send a JSON MQTT message.

bool	publish_json (const char *topic, const json::json_build_t &f)
	Construct and send a JSON MQTT message (no heap allocation for topic).

bool	publish_json (StringRef topic, const json::json_build_t &f)
	Construct and send a JSON MQTT message (no heap allocation for topic).

void	subscribe (const std::string &topic, mqtt_callback_t callback, uint8_t qos=0)
	Subscribe to a MQTT topic.

void	subscribe_json (const std::string &topic, const mqtt_json_callback_t &callback, uint8_t qos=0)
	Subscribe to a MQTT topic and automatically parse JSON payload.

Public Member Functions inherited from esphome::Component
virtual void	loop ()
	This method will be called repeatedly.

float	get_actual_setup_priority () const

void	set_setup_priority (float priority)

virtual float	get_loop_priority () const
	priority of loop().

void	call ()

virtual void	on_shutdown ()

virtual void	on_safe_shutdown ()

virtual bool	teardown ()
	Called during teardown to allow component to gracefully finish operations.

virtual void	on_powerdown ()
	Called after teardown is complete to power down hardware.

uint8_t	get_component_state () const

void	reset_to_construction_state ()
	Reset this component back to the construction state to allow setup to run again.

bool	is_in_loop_state () const
	Check if this component has completed setup and is in the loop state.

bool	is_idle () const
	Check if this component is idle.

void	mark_failed ()
	Mark this component as failed.

	ESPDEPRECATED ("Use mark_failed(LOG_STR(\"static string literal\")) instead. Do NOT use .c_str() from temporary " "strings. Will stop working in 2026.6.0", "2025.12.0") void mark_failed(const char *message)

void	mark_failed (const LogString *message)

void	disable_loop ()
	Disable this component's loop.

void	enable_loop ()
	Enable this component's loop.

void	enable_loop_soon_any_context ()
	Thread and ISR-safe version of enable_loop() that can be called from any context.

bool	is_failed () const

bool	is_ready () const

virtual bool	can_proceed ()

bool	status_has_warning () const

bool	status_has_error () const

void	status_set_warning (const char *message=nullptr)

void	status_set_warning (const LogString *message)

void	status_set_error ()

	ESPDEPRECATED ("Use status_set_error(LOG_STR(\"static string literal\")) instead. Do NOT use .c_str() from temporary " "strings. Will stop working in 2026.6.0", "2025.12.0") void status_set_error(const char *message)

void	status_set_error (const LogString *message)

void	status_clear_warning ()

void	status_clear_error ()

void	status_momentary_warning (const char *name, uint32_t length=5000)
	Set warning status flag and automatically clear it after a timeout.

void	status_momentary_error (const char *name, uint32_t length=5000)
	Set error status flag and automatically clear it after a timeout.

bool	has_overridden_loop () const

void	set_component_source (const LogString *source)
	Set where this component was loaded from for some debug messages.

const LogString *	get_component_log_str () const
	Get the integration where this component was declared as a LogString for logging.

bool	should_warn_of_blocking (uint32_t blocking_time)

Protected Member Functions
const char *	component_type () const override
	Override for MQTTComponent, returns "sensor".

const EntityBase *	get_entity () const override

Protected Member Functions inherited from esphome::mqtt::MQTTComponent
StringRef	get_discovery_topic_to_ (std::span< char, MQTT_DISCOVERY_TOPIC_MAX_LEN > buf, const MQTTDiscoveryInfo &discovery_info) const
	Helper method to get the discovery topic for this component into a buffer.

StringRef	get_default_topic_for_to_ (std::span< char, MQTT_DEFAULT_TOPIC_MAX_LEN > buf, const char *suffix, size_t suffix_len) const
	Get this components state/command/... topic into a buffer.

std::string	get_default_topic_for_ (const std::string &suffix) const
	Get this components state/command/... topic (allocates std::string).

const StringRef &	friendly_name_ () const
	Get the friendly name of this MQTT component.

StringRef	get_icon_ref_ () const
	Get the icon field of this component as StringRef.

bool	is_disabled_by_default_ () const
	Get whether the underlying Entity is disabled by default.

StringRef	get_state_topic_to_ (std::span< char, MQTT_DEFAULT_TOPIC_MAX_LEN > buf) const
	Get the MQTT state topic into a buffer (no heap allocation for non-lambda custom topics).

StringRef	get_command_topic_to_ (std::span< char, MQTT_DEFAULT_TOPIC_MAX_LEN > buf) const
	Get the MQTT command topic into a buffer (no heap allocation for non-lambda custom topics).

std::string	get_state_topic_ () const
	Get the MQTT topic that new states will be shared to (allocates std::string).

std::string	get_command_topic_ () const
	Get the MQTT topic for listening to commands (allocates std::string).

bool	is_connected_ () const

bool	send_discovery_ ()
	Internal method to start sending discovery info, this will call send_discovery().

StringRef	get_default_object_id_to_ (std::span< char, OBJECT_ID_MAX_LEN > buf) const
	Get the object ID for this MQTT component, writing to the provided buffer.

bool	compute_is_internal_ ()
	Compute is_internal status based on topics and entity state.

Protected Member Functions inherited from esphome::Component
void	call_loop_ ()

void	call_dump_config_ ()

void	set_component_state_ (uint8_t state)
	Helper to set component state (clears state bits and sets new state)

bool	set_status_flag_ (uint8_t flag)
	Helper to set a status LED flag on both this component and the app.

void	set_interval (uint32_t id, uint32_t interval, std::function< void()> &&f)
	Set an interval function with a numeric ID (zero heap allocation).

void	set_interval (InternalSchedulerID id, uint32_t interval, std::function< void()> &&f)

void	set_interval (uint32_t interval, std::function< void()> &&f)

bool	cancel_interval (uint32_t id)

bool	cancel_interval (InternalSchedulerID id)

ESPDEPRECATED("set_retry is deprecated and will be removed in 2026.8.0. Use set_timeout or set_interval instead.", "2026.2.0") void set_retry(const std	ESPDEPRECATED ("set_retry is deprecated and will be removed in 2026.8.0. Use set_timeout or set_interval instead.", "2026.2.0") void set_retry(const char *name

	ESPDEPRECATED ("set_retry is deprecated and will be removed in 2026.8.0. Use set_timeout or set_interval instead.", "2026.2.0") void set_retry(uint32_t id

	ESPDEPRECATED ("set_retry is deprecated and will be removed in 2026.8.0. Use set_timeout or set_interval instead.", "2026.2.0") void set_retry(uint32_t initial_wait_time

ESPDEPRECATED("cancel_retry is deprecated and will be removed in 2026.8.0.", "2026.2.0") bool cancel_retry(const std	ESPDEPRECATED ("cancel_retry is deprecated and will be removed in 2026.8.0.", "2026.2.0") bool cancel_retry(const char *name)

	ESPDEPRECATED ("cancel_retry is deprecated and will be removed in 2026.8.0.", "2026.2.0") bool cancel_retry(uint32_t id)

void	set_timeout (uint32_t id, uint32_t timeout, std::function< void()> &&f)
	Set a timeout function with a numeric ID (zero heap allocation).

void	set_timeout (InternalSchedulerID id, uint32_t timeout, std::function< void()> &&f)

void	set_timeout (uint32_t timeout, std::function< void()> &&f)

bool	cancel_timeout (uint32_t id)

bool	cancel_timeout (InternalSchedulerID id)

void	defer (std::function< void()> &&f)
	Defer a callback to the next loop() call.

void	defer (uint32_t id, std::function< void()> &&f)
	Defer a callback with a numeric ID (zero heap allocation)

bool	cancel_defer (uint32_t id)

Protected Attributes
sensor::Sensor *	sensor_

optional< uint32_t >	expire_after_

Protected Attributes inherited from esphome::mqtt::MQTTComponent
TemplatableValue< std::string >	custom_state_topic_ {}

TemplatableValue< std::string >	custom_command_topic_ {}

std::unique_ptr< Availability >	availability_

uint8_t	qos_: 2 {0}

uint8_t	subscribe_qos_: 2 {0}

bool	command_retain_: 1 {false}

bool	retain_: 1 {true}

bool	discovery_enabled_: 1 {true}

bool	resend_state_: 1 {false}

bool	is_internal_: 1 {false}
	Cached result of compute_is_internal_(), set during setup.

Protected Attributes inherited from esphome::Component
ESPDEPRECATED("Use const char* or uint32_t overload instead. Removed in 2026.7.0", "2026.1.0") void set_interval(const std voi	set_interval )(const char *name, uint32_t interval, std::function< void()> &&f)
	Set an interval function with a unique name.

ESPDEPRECATED("Use const char* or uint32_t overload instead. Removed in 2026.7.0", "2026.1.0") bool cancel_interval(const std boo	cancel_interval )(const char *name)
	Cancel an interval function.

ESPDEPRECATED("set_retry is deprecated and will be removed in 2026.8.0. Use set_timeout or set_interval instead.", "2026.2.0") void set_retry(const std uint32_t	initial_wait_time

ESPDEPRECATED("set_retry is deprecated and will be removed in 2026.8.0. Use set_timeout or set_interval instead.", "2026.2.0") void set_retry(const std uint32_t uint8_t	max_attempts

ESPDEPRECATED("set_retry is deprecated and will be removed in 2026.8.0. Use set_timeout or set_interval instead.", "2026.2.0") void set_retry(const std uint32_t uint8_t std::function< RetryResult(uint8_t)> &&	f

ESPDEPRECATED("set_retry is deprecated and will be removed in 2026.8.0. Use set_timeout or set_interval instead.", "2026.2.0") void set_retry(const std uint32_t uint8_t std::function< RetryResult(uint8_t)> float	backoff_increase_factor = 1.0f)

uint32_t	initial_wait_time

uint32_t uint8_t	max_attempts

uint32_t uint8_t std::function< RetryResult(uint8_t)> &&	f

uint32_t uint8_t std::function< RetryResult(uint8_t)> float	backoff_increase_factor = 1.0f)

uint8_t	max_attempts

uint8_t std::function< RetryResult(uint8_t)> &&	f

uint8_t std::function< RetryResult(uint8_t)> float	backoff_increase_factor = 1.0f)

ESPDEPRECATED("Use const char* or uint32_t overload instead. Removed in 2026.7.0", "2026.1.0") void set_timeout(const std voi	set_timeout )(const char *name, uint32_t timeout, std::function< void()> &&f)
	Set a timeout function with a unique name.

ESPDEPRECATED("Use const char* or uint32_t overload instead. Removed in 2026.7.0", "2026.1.0") bool cancel_timeout(const std boo	cancel_timeout )(const char *name)
	Cancel a timeout function.

ESPDEPRECATED("Use const char* overload instead. Removed in 2026.7.0", "2026.1.0") void defer(const std voi	defer )(const char *name, std::function< void()> &&f)
	Defer a callback to the next loop() call.

ESPDEPRECATED("Use const char* overload instead. Removed in 2026.7.0", "2026.1.0") bool cancel_defer(const std boo	cancel_defer )(const char *name)
	Cancel a defer callback using the specified name, name must not be empty.

const LogString *	component_source_ {nullptr}

uint16_t	warn_if_blocking_over_ {WARN_IF_BLOCKING_OVER_MS}
	Warn if blocked for this many ms (max 65.5s)

uint8_t	component_state_ {0x00}
	State of this component - each bit has a purpose: Bits 0-2: Component state (0x00=CONSTRUCTION, 0x01=SETUP, 0x02=LOOP, 0x03=FAILED, 0x04=LOOP_DONE) Bit 3: STATUS_LED_WARNING Bit 4: STATUS_LED_ERROR Bit 5: Has overridden loop() (set at registration time) Bits 6-7: Unused - reserved for future expansion.

volatile bool	pending_enable_loop_ {false}
	ISR-safe flag for enable_loop_soon_any_context.

Detailed Description

Definition at line 13 of file mqtt_sensor.h.

Constructor & Destructor Documentation

◆ MQTTSensorComponent()

esphome::mqtt::MQTTSensorComponent::MQTTSensorComponent ( sensor::Sensor * sensor )

explicit

Construct this MQTTSensorComponent instance with the provided friendly_name and sensor.

Note the sensor is never stored and is only used for initializing some values of this class. If sensor is nullptr, then automatic initialization of these fields is disabled.

Parameters

sensor The sensor, this can be null to disable automatic setup.

Definition at line 20 of file mqtt_sensor.cpp.

Member Function Documentation

◆ component_type()

const char * esphome::mqtt::MQTTSensorComponent::component_type ( ) const

overrideprotectedvirtual

Override for MQTTComponent, returns "sensor".

Implements esphome::mqtt::MQTTComponent.

◆ disable_expire_after()

void esphome::mqtt::MQTTSensorComponent::disable_expire_after ( )

Disable Home Assistant value expiry.

Definition at line 43 of file mqtt_sensor.cpp.

◆ dump_config()

void esphome::mqtt::MQTTSensorComponent::dump_config ( )

overridevirtual

Reimplemented from esphome::Component.

Definition at line 26 of file mqtt_sensor.cpp.

◆ get_entity()

const EntityBase * esphome::mqtt::MQTTSensorComponent::get_entity ( ) const

overrideprotectedvirtual

Implements esphome::mqtt::MQTTComponent.

◆ get_expire_after()

uint32_t esphome::mqtt::MQTTSensorComponent::get_expire_after ( ) const

Get the expire_after in milliseconds used for Home Assistant discovery, first checks override.

◆ publish_state()

bool esphome::mqtt::MQTTSensorComponent::publish_state ( float value )

Definition at line 85 of file mqtt_sensor.cpp.

◆ send_discovery()

void esphome::mqtt::MQTTSensorComponent::send_discovery	(	JsonObject	root,
		mqtt::SendDiscoveryConfig &	config )

overridevirtual

Implements esphome::mqtt::MQTTComponent.

Definition at line 45 of file mqtt_sensor.cpp.

◆ send_initial_state()

bool esphome::mqtt::MQTTSensorComponent::send_initial_state ( )

overridevirtual

Implements esphome::mqtt::MQTTComponent.

Definition at line 78 of file mqtt_sensor.cpp.

◆ set_expire_after()

void esphome::mqtt::MQTTSensorComponent::set_expire_after ( uint32_t expire_after )

Setup an expiry, 0 disables it.

◆ setup()

void esphome::mqtt::MQTTSensorComponent::setup ( )

overridevirtual

Override setup.

Reimplemented from esphome::Component.

Definition at line 22 of file mqtt_sensor.cpp.

Field Documentation

◆ expire_after_

optional<uint32_t> esphome::mqtt::MQTTSensorComponent::expire_after_

protected

Definition at line 50 of file mqtt_sensor.h.

◆ sensor_

sensor::Sensor* esphome::mqtt::MQTTSensorComponent::sensor_

protected

Definition at line 49 of file mqtt_sensor.h.

The documentation for this class was generated from the following files:

esphome/components/mqtt/mqtt_sensor.h
esphome/components/mqtt/mqtt_sensor.cpp

Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ MQTTSensorComponent()

Member Function Documentation

◆ component_type()

◆ disable_expire_after()

◆ dump_config()

◆ get_entity()

◆ get_expire_after()

◆ publish_state()

◆ send_discovery()

◆ send_initial_state()

◆ set_expire_after()

◆ setup()

Field Documentation

◆ expire_after_

◆ sensor_