home-assistant-javascript-templates

home-assistant-javascript-templates

A JavaScript utility to render Home Assistant JavaScript templates.

   

Install

npm

npm install home-assistant-javascript-templates

yarn

yarn add home-assistant-javascript-templates

PNPM

pnpm add home-assistant-javascript-templates

Basic Usage

Usage with commonJS

const HomeAssistantJavaScriptTemplates = require('home-assistant-javascript-templates');

const renderer = new HomeAssistantJavaScriptTemplates(
    document.querySelector('home-assistant').hass
);

renderer.renderTemplate('... template string ...');

Usage with ES6 modules

import HomeAssistantJavaScriptTemplates  from 'home-assistant-javascript-templates';

const renderer = new HomeAssistantJavaScriptTemplates(
    document.querySelector('home-assistant').hass
);

renderer.renderTemplate('... template string ...');

API

The package exposes a class that needs to be instantiated and is this isntance the one that you need to use in your code.

HomeAssistantJavaScriptTemplates class

Main class of the library, it is the default export in the package.

new HomeAssistantJavaScriptTemplates(hass, throwErrors = false);

Parameter	Optional	Description
hass	no	A valid hass object
throwErrors	yes	Indicates if the library should throw if the template contains any error. If not it will log the errors as a warning in the console.

renderTemplate method

This is the main method to render JavaScript templates, it needs a string as a parameter. Inside this string you can use several objects and methods.

Objects and methods available in the templates

hass

The same hass object that was sent to the class

states

States could be used in two ways, as a function or as an object.

// Using states as a function
states('device_tracker.paulus')

// Using states as an object
states['device_tracker.paulus'].state

is_state

Method to check if the state of an entity is equal to a certain value. It returns a boolean. If the entity id doesn‘t exist it returns false.

is_state('device_tracker.paulus', 'not_home')

state_attr

Method to return the value of the state attribute or None if it doesn’t exist.

state_attr('device_tracker.paulus', 'battery')

is_state_attr

Method to test if the given entity attribute is the specified state. It returns a boolean, if the entity doesn‘t exist it returns false.

is_state_attr('device_tracker.paulus', 'battery', 40)

has_value

Method to test if the given entity is not unknown or unavailable. It returns a boolean, if the entity doesn‘t exist it returns false.

has_value('sensor.my_sensor')

device_attr

Method that returns the value of an attribute for the given device id or None if it doesn’t exist.

device_attr('706ad0ebe27e105d7cd0b73386deefdd')

is_device_attr

Method to test if the value of a device attribute matches a value. It returns a boolean, if the device id doen‘t exist it returns false.

is_device_attr('706ad0ebe27e105d7cd0b73386deefdd', 'manufacturer', 'Synology')

device_id

Method to return the device id for a given entity id or None if the entity doesn‘t exist.

device_id('sensor.my_sensor')

areas

Method to return an array with all the areas ids.

areas()

area_id

Method to return the area id for a given device id, entity id, or area name. It returns None if the area doesn‘t exist.

area_id('b8c1c9dd23cb82bbfa09b5657f41d04f')
area_id('sensor.my_sensor')
area_id('Woonkamer')

area_name

Method to return the area name for a given device id, entity id, or area id. It returns None if the area doesn‘t exist.

area_name('b8c1c9dd23cb82bbfa09b5657f41d04f')
area_name('sensor.my_sensor')
area_name('woonkamer')

area_entities

Method to return an array of entity ids tied to a given area id or area name. If the area doesn‘t exist it returns an empty array.

area_entities('woonkamer')
area_entities('Woonkamer')

area_devices

Method to return an array of device ids tied to a given area id or area name. If the area doesn‘t exist it returns an empty array.

area_devices('woonkamer')
area_devices('Woonkamer')

Example

import HomeAssistantJavaScriptTemplates  from 'home-assistant-javascript-templates';

const renderer = new HomeAssistantJavaScriptTemplates(
    document.querySelector('home-assistant').hass
);

/**
 * Get the device id of an entity
 * With the device id get an attribute of the device
 * Return the value of the attribute prefixed with "sn: "
 * It will return something like "sn: 123456"
 */
renderer.renderTemplate(`
    const deviceId = device_id("binary_sensor.koffiezetapparaat_aan");
    const serialNumber = device_attr(deviceId, "serial_number");
    return "sn:" + serialNumber;
`);

Changelog

[1.0.1] - 2024-01-28

• Exports the Hass interface