This repository provides examples and basic empty components that can be used as templates to quickly develop your own custom components for the splendid ESPHome ESP8266/ESP32 home automation system.
All sample components can be found in the custom_components
directory. The test_empty_components.yaml
file provides configuration examples for the various custom components. To use a particular component for your project, do the following:
-
Create a
custom_components
directory in your esphome configuration directory (the directory where your.yaml
files are) -
Copy the directory of an empty component to
custom_components
in its entirety, so you end up with e.g.custom_components/empty_sensor/
-
Find the configuration entry for the empty component in
test_empty_components.yaml
and copy it into your own.yaml
file. -
Compile with
esphome your_config.yaml compile
(changeyour_config.yaml
to your own.yaml
file) or compile with the dashboard. -
No errors? Great! You can now start modifying the empty component into your own custom component.
Let's start with the simplest custom component:
custom_components
├── empty_component
│ ├── __init.py__
│ ├── empty_component.cpp
│ ├── empty_component.h
│ ...
The __init.py__
file contains 2 main things:
- configuration validation or cv
- code generation or cg
cv handles validation of user input in the .yaml
configuration file for this particular component: defining the available configuration options, whether they are required or optional, any constraints on the types and values of an option, etc.
cg takes these validated configuration options and generates the code necessary to streamline them into your c++ code, as well as registering your component properly within the ESPHome runtime.
The .cpp
and .h
files are the main source code files for your component. You're free to add to or modify the structure of the source code within the constraints of c++
, but your code needs at least one class
derived from Component
that will be registered in the __init__.py
.
If your component yields a specific type of component, e.g. a sensor
or a switch
, ESPHome will instead look for a sensor.py
or switch.py
.
The structure of these is identical to that of __init__.py
.
See for example:
custom_components
├── empty_binary_sensor
│ ├── binary_sensor.py
│ ├── empty_binary_sensor.cpp
│ ├── empty_binary_sensor.h
│ ...
There is no __init__.py
here, instead we have a binary_sensor.py
.