ESPHome  2022.11.3
Public Member Functions | Protected Member Functions | Protected Attributes
esphome::mqtt::MQTTComponent Class Referenceabstract

MQTTComponent is the base class for all components that interact with MQTT to expose certain functionality or data from actuators or sensors to clients. More...

#include <mqtt_component.h>

Inheritance diagram for esphome::mqtt::MQTTComponent:
esphome::Component esphome::mqtt::MQTTBinarySensorComponent esphome::mqtt::MQTTButtonComponent esphome::mqtt::MQTTClimateComponent esphome::mqtt::MQTTCoverComponent esphome::mqtt::MQTTFanComponent esphome::mqtt::MQTTJSONLightComponent esphome::mqtt::MQTTLockComponent esphome::mqtt::MQTTNumberComponent esphome::mqtt::MQTTSelectComponent esphome::mqtt::MQTTSensorComponent esphome::mqtt::MQTTSwitchComponent esphome::mqtt::MQTTTextSensor

Public Member Functions

 MQTTComponent ()
 Constructs a MQTTComponent. More...
 
void call_setup () override
 Override setup_ so that we can call send_discovery() when needed. More...
 
void call_loop () override
 
void call_dump_config () override
 
virtual void send_discovery (JsonObject root, SendDiscoveryConfig &config)=0
 Send discovery info the Home Assistant, override this. More...
 
virtual bool send_initial_state ()=0
 
virtual bool is_internal ()
 
void set_retain (bool retain)
 Set whether state message should be retained. More...
 
bool get_retain () const
 
void disable_discovery ()
 Disable discovery. Sets friendly name to "". More...
 
bool is_discovery_enabled () const
 
virtual std::string component_type () const =0
 Override this method to return the component type (e.g. "light", "sensor", ...) More...
 
void set_custom_state_topic (const std::string &custom_state_topic)
 Set a custom state topic. Set to "" for default behavior. More...
 
void set_custom_command_topic (const std::string &custom_command_topic)
 Set a custom command topic. Set to "" for default behavior. More...
 
void set_command_retain (bool command_retain)
 Set whether command message should be retained. More...
 
float get_setup_priority () const override
 MQTT_COMPONENT setup priority. More...
 
void set_availability (std::string topic, std::string payload_available, std::string payload_not_available)
 Set the Home Assistant availability data. More...
 
void disable_availability ()
 
void schedule_resend_state ()
 Internal method for the MQTT client base to schedule a resend of the state on reconnect. More...
 
bool publish (const std::string &topic, const std::string &payload)
 Send a MQTT message. More...
 
bool publish_json (const std::string &topic, const json::json_build_t &f)
 Construct and send a JSON MQTT message. More...
 
void subscribe (const std::string &topic, mqtt_callback_t callback, uint8_t qos=0)
 Subscribe to a MQTT topic. More...
 
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. More...
 
- Public Member Functions inherited from esphome::Component
virtual void setup ()
 Where the component's initialization should happen. More...
 
virtual void loop ()
 This method will be called repeatedly. More...
 
virtual void dump_config ()
 
float get_actual_setup_priority () const
 
void set_setup_priority (float priority)
 
virtual float get_loop_priority () const
 priority of loop(). More...
 
void call ()
 
virtual void on_shutdown ()
 
virtual void on_safe_shutdown ()
 
uint32_t get_component_state () const
 
virtual void mark_failed ()
 Mark this component as failed. More...
 
bool is_failed ()
 
virtual bool can_proceed ()
 
bool status_has_warning ()
 
bool status_has_error ()
 
void status_set_warning ()
 
void status_set_error ()
 
void status_clear_warning ()
 
void status_clear_error ()
 
void status_momentary_warning (const std::string &name, uint32_t length=5000)
 
void status_momentary_error (const std::string &name, uint32_t length=5000)
 
bool has_overridden_loop () const
 
void set_component_source (const char *source)
 Set where this component was loaded from for some debug messages. More...
 
const char * get_component_source () const
 Get the integration where this component was declared as a string. More...
 

Protected Member Functions

std::string get_discovery_topic_ (const MQTTDiscoveryInfo &discovery_info) const
 Helper method to get the discovery topic for this component. More...
 
std::string get_default_topic_for_ (const std::string &suffix) const
 Get this components state/command/... More...
 
virtual const EntityBaseget_entity () const =0
 Gets the Entity served by this MQTT component. More...
 
virtual std::string unique_id ()
 A unique ID for this MQTT component, empty for no unique id. More...
 
virtual std::string friendly_name () const
 Get the friendly name of this MQTT component. More...
 
virtual std::string get_icon () const
 Get the icon field of this component. More...
 
virtual bool is_disabled_by_default () const
 Get whether the underlying Entity is disabled by default. More...
 
std::string get_state_topic_ () const
 Get the MQTT topic that new states will be shared to. More...
 
std::string get_command_topic_ () const
 Get the MQTT topic for listening to commands. More...
 
bool is_connected_ () const
 
bool send_discovery_ ()
 Internal method to start sending discovery info, this will call send_discovery(). More...
 
std::string get_default_object_id_ () const
 Generate the Home Assistant MQTT discovery object id by automatically transforming the friendly name. More...
 
- Protected Member Functions inherited from esphome::Component
void set_interval (const std::string &name, uint32_t interval, std::function< void()> &&f)
 Set an interval function with a unique name. More...
 
void set_interval (uint32_t interval, std::function< void()> &&f)
 
bool cancel_interval (const std::string &name)
 Cancel an interval function. More...
 
void set_retry (const std::string &name, uint32_t initial_wait_time, uint8_t max_attempts, std::function< RetryResult()> &&f, float backoff_increase_factor=1.0f)
 Set an retry function with a unique name. More...
 
void set_retry (uint32_t initial_wait_time, uint8_t max_attempts, std::function< RetryResult()> &&f, float backoff_increase_factor=1.0f)
 
bool cancel_retry (const std::string &name)
 Cancel a retry function. More...
 
void set_timeout (const std::string &name, uint32_t timeout, std::function< void()> &&f)
 Set a timeout function with a unique name. More...
 
void set_timeout (uint32_t timeout, std::function< void()> &&f)
 
bool cancel_timeout (const std::string &name)
 Cancel a timeout function. More...
 
void defer (const std::string &name, std::function< void()> &&f)
 Defer a callback to the next loop() call. More...
 
void defer (std::function< void()> &&f)
 Defer a callback to the next loop() call. More...
 
bool cancel_defer (const std::string &name)
 Cancel a defer callback using the specified name, name must not be empty. More...
 

Protected Attributes

std::string custom_state_topic_ {}
 
std::string custom_command_topic_ {}
 
bool command_retain_ {false}
 
bool retain_ {true}
 
bool discovery_enabled_ {true}
 
std::unique_ptr< Availabilityavailability_
 
bool resend_state_ {false}
 
- Protected Attributes inherited from esphome::Component
uint32_t component_state_ {0x0000}
 State of this component. More...
 
float setup_priority_override_ {NAN}
 
const char * component_source_ {nullptr}
 

Detailed Description

MQTTComponent is the base class for all components that interact with MQTT to expose certain functionality or data from actuators or sensors to clients.

Although this class should work with all MQTT solutions, it has been specifically designed for use with Home Assistant. For example, this class supports Home Assistant MQTT discovery out of the box.

In order to implement automatic Home Assistant discovery, all sub-classes should:

  1. Implement send_discovery that creates a Home Assistant discovery payload.
  2. Override component_type() to return the appropriate component type such as "light" or "sensor".
  3. Subscribe to command topics using subscribe() or subscribe_json() during setup().

In order to best separate the front- and back-end of ESPHome, all sub-classes should only parse/send MQTT messages and interact with back-end components via callbacks to ensure a clean separation.

Definition at line 60 of file mqtt_component.h.

Constructor & Destructor Documentation

◆ MQTTComponent()

esphome::mqtt::MQTTComponent::MQTTComponent ( )
explicitdefault

Constructs a MQTTComponent.

Member Function Documentation

◆ call_dump_config()

void esphome::mqtt::MQTTComponent::call_dump_config ( )
overridevirtual

Reimplemented from esphome::Component.

Definition at line 224 of file mqtt_component.cpp.

◆ call_loop()

void esphome::mqtt::MQTTComponent::call_loop ( )
overridevirtual

Reimplemented from esphome::Component.

Definition at line 204 of file mqtt_component.cpp.

◆ call_setup()

void esphome::mqtt::MQTTComponent::call_setup ( )
overridevirtual

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

Reimplemented from esphome::Component.

Definition at line 183 of file mqtt_component.cpp.

◆ component_type()

virtual std::string esphome::mqtt::MQTTComponent::component_type ( ) const
pure virtual

◆ disable_availability()

void esphome::mqtt::MQTTComponent::disable_availability ( )

Definition at line 182 of file mqtt_component.cpp.

◆ disable_discovery()

void esphome::mqtt::MQTTComponent::disable_discovery ( )

Disable discovery. Sets friendly name to "".

Definition at line 166 of file mqtt_component.cpp.

◆ friendly_name()

std::string esphome::mqtt::MQTTComponent::friendly_name ( ) const
protectedvirtual

Get the friendly name of this MQTT component.

Definition at line 235 of file mqtt_component.cpp.

◆ get_command_topic_()

std::string esphome::mqtt::MQTTComponent::get_command_topic_ ( ) const
protected

Get the MQTT topic for listening to commands.

Definition at line 36 of file mqtt_component.cpp.

◆ get_default_object_id_()

std::string esphome::mqtt::MQTTComponent::get_default_object_id_ ( ) const
protected

Generate the Home Assistant MQTT discovery object id by automatically transforming the friendly name.

Definition at line 151 of file mqtt_component.cpp.

◆ get_default_topic_for_()

std::string esphome::mqtt::MQTTComponent::get_default_topic_for_ ( const std::string &  suffix) const
protected

Get this components state/command/...

topic.

Parameters
suffixThe suffix/key such as "state" or "command".
Returns
The full topic.

Definition at line 25 of file mqtt_component.cpp.

◆ get_discovery_topic_()

std::string esphome::mqtt::MQTTComponent::get_discovery_topic_ ( const MQTTDiscoveryInfo discovery_info) const
protected

Helper method to get the discovery topic for this component.

Definition at line 19 of file mqtt_component.cpp.

◆ get_entity()

virtual const EntityBase* esphome::mqtt::MQTTComponent::get_entity ( ) const
protectedpure virtual

◆ get_icon()

std::string esphome::mqtt::MQTTComponent::get_icon ( ) const
protectedvirtual

Get the icon field of this component.

Definition at line 236 of file mqtt_component.cpp.

◆ get_retain()

bool esphome::mqtt::MQTTComponent::get_retain ( ) const

Definition at line 145 of file mqtt_component.cpp.

◆ get_setup_priority()

float esphome::mqtt::MQTTComponent::get_setup_priority ( ) const
overridevirtual

MQTT_COMPONENT setup priority.

Reimplemented from esphome::Component.

Definition at line 165 of file mqtt_component.cpp.

◆ get_state_topic_()

std::string esphome::mqtt::MQTTComponent::get_state_topic_ ( ) const
protected

Get the MQTT topic that new states will be shared to.

Definition at line 30 of file mqtt_component.cpp.

◆ is_connected_()

bool esphome::mqtt::MQTTComponent::is_connected_ ( ) const
protected

Definition at line 232 of file mqtt_component.cpp.

◆ is_disabled_by_default()

bool esphome::mqtt::MQTTComponent::is_disabled_by_default ( ) const
protectedvirtual

Get whether the underlying Entity is disabled by default.

Definition at line 237 of file mqtt_component.cpp.

◆ is_discovery_enabled()

bool esphome::mqtt::MQTTComponent::is_discovery_enabled ( ) const

Definition at line 147 of file mqtt_component.cpp.

◆ is_internal()

bool esphome::mqtt::MQTTComponent::is_internal ( )
virtual

Definition at line 238 of file mqtt_component.cpp.

◆ publish()

bool esphome::mqtt::MQTTComponent::publish ( const std::string &  topic,
const std::string &  payload 
)

Send a MQTT message.

Parameters
topicThe topic.
payloadThe payload.

Definition at line 42 of file mqtt_component.cpp.

◆ publish_json()

bool esphome::mqtt::MQTTComponent::publish_json ( const std::string &  topic,
const json::json_build_t f 
)

Construct and send a JSON MQTT message.

Parameters
topicThe topic.
fThe Json Message builder.

Definition at line 48 of file mqtt_component.cpp.

◆ schedule_resend_state()

void esphome::mqtt::MQTTComponent::schedule_resend_state ( )

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

Definition at line 230 of file mqtt_component.cpp.

◆ send_discovery()

virtual void esphome::mqtt::MQTTComponent::send_discovery ( JsonObject  root,
SendDiscoveryConfig config 
)
pure virtual

◆ send_discovery_()

bool esphome::mqtt::MQTTComponent::send_discovery_ ( )
protected

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

Definition at line 54 of file mqtt_component.cpp.

◆ send_initial_state()

virtual bool esphome::mqtt::MQTTComponent::send_initial_state ( )
pure virtual

◆ set_availability()

void esphome::mqtt::MQTTComponent::set_availability ( std::string  topic,
std::string  payload_available,
std::string  payload_not_available 
)

Set the Home Assistant availability data.

See See Home Assistant for more info.

Definition at line 175 of file mqtt_component.cpp.

◆ set_command_retain()

void esphome::mqtt::MQTTComponent::set_command_retain ( bool  command_retain)

Set whether command message should be retained.

Definition at line 173 of file mqtt_component.cpp.

◆ set_custom_command_topic()

void esphome::mqtt::MQTTComponent::set_custom_command_topic ( const std::string &  custom_command_topic)

Set a custom command topic. Set to "" for default behavior.

Definition at line 170 of file mqtt_component.cpp.

◆ set_custom_state_topic()

void esphome::mqtt::MQTTComponent::set_custom_state_topic ( const std::string &  custom_state_topic)

Set a custom state topic. Set to "" for default behavior.

Definition at line 167 of file mqtt_component.cpp.

◆ set_retain()

void esphome::mqtt::MQTTComponent::set_retain ( bool  retain)

Set whether state message should be retained.

Definition at line 17 of file mqtt_component.cpp.

◆ subscribe()

void esphome::mqtt::MQTTComponent::subscribe ( const std::string &  topic,
mqtt_callback_t  callback,
uint8_t  qos = 0 
)

Subscribe to a MQTT topic.

Parameters
topicThe topic. Wildcards are currently not supported.
callbackThe callback that will be called when a message with matching topic is received.
qosThe MQTT quality of service. Defaults to 0.

Definition at line 155 of file mqtt_component.cpp.

◆ subscribe_json()

void esphome::mqtt::MQTTComponent::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.

If an invalid JSON payload is received, the callback will not be called.

Parameters
topicThe topic. Wildcards are currently not supported.
callbackThe callback with a parsed JsonObject that will be called when a message with matching topic is received.
qosThe MQTT quality of service. Defaults to 0.

Definition at line 159 of file mqtt_component.cpp.

◆ unique_id()

std::string esphome::mqtt::MQTTComponent::unique_id ( )
protectedvirtual

A unique ID for this MQTT component, empty for no unique id.

See unique ID requirements: https://developers.home-assistant.io/docs/en/entity_registry_index.html#unique-id-requirements

Returns
The unique id as a string.

Reimplemented in esphome::mqtt::MQTTSensorComponent, and esphome::mqtt::MQTTTextSensor.

Definition at line 231 of file mqtt_component.cpp.

Field Documentation

◆ availability_

std::unique_ptr<Availability> esphome::mqtt::MQTTComponent::availability_
protected

Definition at line 196 of file mqtt_component.h.

◆ command_retain_

bool esphome::mqtt::MQTTComponent::command_retain_ {false}
protected

Definition at line 193 of file mqtt_component.h.

◆ custom_command_topic_

std::string esphome::mqtt::MQTTComponent::custom_command_topic_ {}
protected

Definition at line 192 of file mqtt_component.h.

◆ custom_state_topic_

std::string esphome::mqtt::MQTTComponent::custom_state_topic_ {}
protected

Definition at line 191 of file mqtt_component.h.

◆ discovery_enabled_

bool esphome::mqtt::MQTTComponent::discovery_enabled_ {true}
protected

Definition at line 195 of file mqtt_component.h.

◆ resend_state_

bool esphome::mqtt::MQTTComponent::resend_state_ {false}
protected

Definition at line 197 of file mqtt_component.h.

◆ retain_

bool esphome::mqtt::MQTTComponent::retain_ {true}
protected

Definition at line 194 of file mqtt_component.h.


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