Global Variables in Home Assistant

1.Great for triggers, conditions, and actions

2.When the automation ends, the variable disappears (not persisted).

1.use a Trigger-based Template Sensor detail1

2.config/custom_templates.detail

json file

1.use templating json

use custom integration

https://github.com/rogro82/hass-variables

action:
  - service: variable.set_variable
    data:
      variable: last_motion
      value: "livingroom"
      attributes_template: >
        {
          "history_1": "{{ variable.state }}",
          "history_2": "{{ variable.attributes.history_1 }}",
          "history_3": "{{ variable.attributes.history_2 }}"
        }

- sensor:
      - name: "storen_data"
        state: "active"
        attributes:
          data: |
            {{ {"gaestebad": {
              "entity_id": "cover.storen_1_cec9_storen_1_gaestebad",
              "azimuth_min": 135,
              "azimuth_max": 225,
              "position_default": 100,
              "tilt_default": 100,
              "position_vor_abends": 0,
              "tilt_vor_abends": 30,
              "position_abends": 0,
              "tilt_abends": 0,
              "position_nacht": 0,  
              "tilt_nacht": 0,
              "position_sonnenschutz": 0,
              "tilt_sonnenschutz": 40,
              "window_sensor": "sensor.custom_fenster_status_gaestebad",
              "automation_active_sensor": "input_boolean.storen_automatic_gaestebad_fenster"} } }}

{{state_attr('sensor.storen_data', 'data').gaestebad.azimuth_min}}

1.detail

detail

Handle custom events

# this configuration can be placed in configuration.yaml
- trigger:
    - platform: event
      event_type: set_variable
    - platform: event
      event_type: remove_variable
    - platform: event
      event_type: clear_variables
  condition:
    - condition: template
      value_template: >
        {{
            (
              trigger.event.event_type == 'set_variable'
              and trigger.event.data is defined
              and trigger.event.data.key is defined
              and trigger.event.data.value is defined
            )
            or
            (
              trigger.event.event_type == 'remove_variable'
              and trigger.event.data is defined
              and trigger.event.data.key is defined
            )
            or 
            trigger.event.event_type == 'clear_variables'
        }}
  action:
    - if: "{{ trigger.event.data.get('log', state_attr('sensor.variables', 'log_events')) }}"
      then:
        - service: logbook.log
          data:
            name: "{{ trigger.event.event_type }}:"
            message: >
              {{ trigger.event.data.key | default('All variables removed') }}
              {%- if trigger.event.event_type == 'set_variable' -%}
                : {{ trigger.event.data.value }}.
              {%- endif -%}
  sensor:
    - unique_id: 4a4c8e53-9e68-4198-9cc5-b336e228ea4d
      name: Variables
      state: Variables
      attributes:
        default_timestamp: false
        log_events: false
        variables: >
          {% set others = dict(this.attributes.get('variables', {}).items() | rejectattr('0', 'eq', trigger.event.data.key)) %}
          {% if trigger.event.event_type == 'set_variable'
              and trigger.event.data.get('set_timestamp', this.attributes.get('default_timestamp', false))
          %}
            {% set value  = trigger.event.data.value %}
            {% set value = value.isoformat() if value is datetime else value %}
            {% set new = {trigger.event.data.key: {'value': value, 'timestamp': now().isoformat()}} %}
            {{ dict(others, **new) }}
          {% elif trigger.event.event_type == 'set_variable' %}
            {% set new = {trigger.event.data.key: trigger.event.data.value} %}
            {{ dict(others, **new) }}
          {% elif trigger.event.event_type == 'remove_variable' %}
            {{ others }}
          {% elif trigger.event.event_type == 'clear_variables' %}
            {}
          {% endif %}

post

http://homeassistant.local:8123/api/states/:entity_id

{
    "state": "below_horizon",
    "attributes": {
        "next_rising":"2016-05-31T03:39:14+00:00",
        "next_setting":"2016-05-31T19:16:42+00:00"
    }
}

/data/homeassistant202405/custom_template/stations.jinja

{% macro stations_data() %}
[
    {
      "name": "Station One",
      "url": "https://one.example.com",
      "inital_volume": 120
    },
    {
      "name": "Radio two",
      "url": "https://two.example.com",
      "inital_volume": 100
    },
    {
      "name": "LiveTalk",
      "url": "https://three.example.com",
      "inital_volume": 110
    }
  ]
{% endmacro %}

json file

1.use templating json

import json

# Read from file and parse JSON
with open("sample.json", "r") as f:
    data = json.load(f)

print(data)
print(type(data))

import json
data = {
    "name": "sathiyajith",
    "rollno": 56,
    "cgpa": 8.6,
    "phone": "9976770500"
}

with open("sample.json", "w") as f:
    json.dump(data, f)

This integration can expose regular REST commands as actions. Actions can be called from a script or in automation

detail

2.detail

1.detail

2.detail

template:
  - binary_sensor:
      - name: "Chinese Holiday Today"
        state: >
          {% set file = '/config/data/holiday-cn-2025.json' %}
          {% set data = read_file(file) | from_json %}
          {% set today = now().strftime('%Y-%m-%d') %}
          {% set holiday = data | selectattr('date', 'equalto', today) | list %}
          {{ holiday | count > 0 }}
        attributes:
          friendly_name: "Is today a Chinese holiday?"

json file +restful api template sensor in configuration.yaml

https://www.home-assistant.io/integrations/sensor.rest/

post

http://homeassistant.local:8123/api/states/:entity_id

{
    "state": "below_horizon",
    "attributes": {
        "next_rising":"2016-05-31T03:39:14+00:00",
        "next_setting":"2016-05-31T19:16:42+00:00"
    }
}

http json+rest_command

rest_command:
  secured_command:
    url: "http://example.com/api/secure-endpoint"
    method: post
    authentication: digest
    username: "your_username"
    password: "your_password"
    payload: '{"data": "example"}'
    content_type: "application/json"

1.detail

2.detail

command_line:
  - sensor:
      name: JSON user
      command: python3 -c "import requests; print(requests.get('https://jsonplaceholder.typicode.com/users').text)"
      json_attributes_path: "$.[0].address"
      json_attributes:
        - street
        - suite
        - city
        - zipcode
      value_template: "{{ value_json[0].name }}"