esphome-docs/components/text_sensor/index.rst
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Text Sensor Component
=====================
.. seo::
:description: Instructions for setting up text sensors that represent their state as a string of text.
:image: folder-open.svg
Text sensors are a lot like normal :doc:`sensors </components/sensor/index>`.
But where the "normal" sensors only represent sensors that output **numbers**, this
component can represent any *text*.
.. _config-text_sensor:
Base Text Sensor Configuration
------------------------------
.. code-block:: yaml
# Example sensor configuration
name: Livingroom Temperature
# Optional variables:
icon: "mdi:water-percent"
Configuration variables:
- **id** (*Optional*, string): Manually specify the ID for code generation. At least one of **id** and **name** must be specified.
- **name** (*Optional*, string): The name for the sensor. At least one of **id** and **name** must be specified.
.. note::
If you have a :ref:`friendly_name <esphome-configuration_variables>` set for your device and
you want the text sensor to use that name, you can set ``name: None``.
- **icon** (*Optional*, icon): Manually set the icon to use for the sensor in the frontend.
- **device_class** (*Optional*, string): The device class for the
sensor. Only the ``timestamp`` and ``date`` device classes are supported.
Set to ``""`` to remove the default device class of a sensor.
Requires Home Assistant 2024.3 or newer.
- **internal** (*Optional*, boolean): Mark this component as internal. Internal components will
not be exposed to the frontend (like Home Assistant). Only specifying an ``id`` without
a ``name`` will implicitly set this to true.
- **disabled_by_default** (*Optional*, boolean): If true, then this entity should not be added to any client's frontend,
(usually Home Assistant) without the user manually enabling it (via the Home Assistant UI).
Defaults to ``false``.
- **entity_category** (*Optional*, string): The category of the entity.
See https://developers.home-assistant.io/docs/core/entity/#generic-properties
for a list of available options.
Set to ``""`` to remove the default entity category.
- If MQTT enabled, All other options from :ref:`MQTT Component <config-mqtt-component>`.
- If Webserver enabled, ``web_server_sorting_weight`` can be set. See :ref:`Webserver Entity Sorting <config-webserver-sorting>`.
Automations:
- **on_value** (*Optional*, :ref:`Automation <automation>`): An automation to perform
when a new value is published. See :ref:`text_sensor-on_value`.
- **on_raw_value** (*Optional*, :ref:`Automation <automation>`): An automation to perform
when a new value is received that hasn't passed through any filters. See :ref:`text_sensor-on_raw_value`.
.. _text_sensor-filters:
Text Sensor Filters
-------------------
ESPHome allows you to do some basic pre-processing of
text_sensor values before theyre sent to Home Assistant. This is for example
useful if you want to manipulate the text_sensor string in some fashion.
There are a lot of filters that sensors support. You define them by adding a ``filters``
block in the text_sensor configuration (at the same level as ``platform``; or inside each text_sensor block
for platforms with multiple sensors).
Filters are processed in the order they are defined in your configuration.
.. code-block:: yaml
# Example filters:
filters:
- to_upper:
- to_lower:
- append: "_suffix"
- prepend: "prefix_"
- substitute:
- "suf -> foo"
- "pre -> bar"
- lambda: return {"Hello World"};
``to_upper``
************
Converts all characters within a string to uppercase (only the English alphabet is supported at this time).
.. code-block:: yaml
# Example configuration entry
- platform: template
# ...
filters:
- to_upper:
``to_lower``
************
Converts all characters within a string to lowercase (only the English alphabet is supported at this time).
.. code-block:: yaml
# Example configuration entry
- platform: template
# ...
filters:
- to_lower:
``append``
**********
Adds a string to the end of the current string.
.. code-block:: yaml
# Example configuration entry
- platform: template
# ...
filters:
- append: "_suffix"
``prepend``
***********
Adds a string to the start of the current string.
.. code-block:: yaml
# Example configuration entry
- platform: template
# ...
filters:
- prepend: "prefix_"
``substitute``
**************
Search the current value of the text sensor for a string, and replace it with another string.
.. code-block:: yaml
# Example configuration entry
- platform: template
# ...
filters:
- substitute:
- "suf -> foo"
- "pre -> bar"
The arguments are a list of substitutions, each in the form ``TO_FIND -> REPLACEMENT``.
``map``
*******
Lookup the current value of the text sensor in a list, and return the matching item if found.
Does not change the value of the text sensor if the current value wasn't found.
.. code-block:: yaml
# Example configuration entry
- platform: template
# ...
filters:
- map:
- high -> On
- low -> Off
The arguments are a list of substitutions, each in the form ``LOOKUP -> REPLACEMENT``.
``lambda``
**********
Perform a advanced operations on the text sensor value. The input string is ``x`` and
the result of the lambda is used as the output (use ``return``).
.. code-block:: yaml
filters:
- lambda: |-
if (x == "Hello") {
return x + "bar";
} else {
return x + "foo";
}
Text Sensor Automation
----------------------
You can access the most recent state of the sensor in :ref:`lambdas <config-lambda>` using
``id(sensor_id).state``.
.. _text_sensor-on_value:
``on_value``
************
This automation will be triggered when a new value is published.
In :ref:`Lambdas <config-lambda>` you can get the value from the trigger with ``x``.
.. code-block:: yaml
text_sensor:
- platform: version
# ...
on_value:
then:
- lambda: |-
ESP_LOGD("main", "The current version is %s", x.c_str());
Configuration variables: See :ref:`Automation <automation>`.
.. _text_sensor-on_raw_value:
``on_raw_value``
****************
This automation will be triggered when a new value is received that hasn't passed
through any filters. In :ref:`Lambdas <config-lambda>` you can get the value from the trigger with ``x``.
.. code-block:: yaml
text_sensor:
- platform: version
# ...
on_raw_value:
then:
- lambda: |-
ESP_LOGD("main", "The current version is %s", x.c_str());
Configuration variables: See :ref:`Automation <automation>`.
.. _text_sensor-state_condition:
``text_sensor.state`` Condition
-------------------------------
This :ref:`Condition <config-condition>` allows you to check if a given text sensor
has a specific state.
.. code-block:: yaml
on_...:
- if:
condition:
# Checks if "my_text_sensor" has state "Hello World"
text_sensor.state:
id: my_text_sensor
state: 'Hello World'
Configuration variables:
- **id** (**Required**, :ref:`config-id`): The text sensor ID.
- **state** (**Required**, :ref:`templatable <config-templatable>`, string): The state to compare
to.
.. note::
This condition can also be expressed in :ref:`lambdas <config-lambda>`:
.. code-block:: cpp
if (id(my_text_sensor).state == "Hello World") {
// do something
}
.. _text_sensor-lambda_calls:
lambda calls
************
From :ref:`lambdas <config-lambda>`, you can call several methods on all text sensors to do some
advanced stuff (see the full API Reference for more info).
- ``publish_state()``: Manually cause the sensor to push out a value.
.. code-block:: cpp
// Within lambda, push a value of "Hello World"
id(my_sensor).publish_state("Hello World");
- ``.state``: Retrieve the current value of the sensor as an ``std::string`` object.
.. code-block:: cpp
// For example, create a custom log message when a value is received:
std::string val = id(my_sensor).state;
ESP_LOGI("main", "Value of my sensor: %s", val.c_str());
See Also
--------
- :apiref:`text_sensor/text_sensor.h`
- :ghedit:`Edit`
.. toctree::
:maxdepth: 1
:glob:
*