home-assistant.io/source/_integrations/file.markdown

title	description	logo	ha_category	ha_release	ha_iot_class
File	Instructions on how to integrate sensors which read from files into Home Assistant.	file.png	Utility Notifications Sensor	pre 0.7	Local Polling

There is currently support for the following device types within Home Assistant:

• Notifications
• Sensor

Notifications

The file platform allows you to store notifications from Home Assistant as a file.

To enable file notifications in your installation, add the following to your configuration.yaml file:

# Example configuration.yaml entry
notify:
  - name: NOTIFIER_NAME
    platform: file
    filename: FILENAME

{% configuration %} name: description: Setting the optional parameter name allows multiple notifiers to be created. The notifier will bind to the service notify.NOTIFIER_NAME. required: false default: notify type: string filename: description: Name of the file to use. The file will be created if it doesn't exist and saved in your configuration folder. required: true type: string timestamp: description: Setting timestamp to true adds a timestamp to every entry. required: false default: false type: boolean {% endconfiguration %}

To use notifications, please see the getting started with automation page.

Sensor

The file sensor platform reads the entries from a plain-text file and shows the found value. Only the last line of the file is used. This is similar to do $ tail -n 1 sensor.txt on the command-line. Note that file paths must be added to whitelist_external_dirs.

To enable the file sensor, add the following lines to your configuration.yaml:

# Example configuration.yaml entry
sensor:
  - platform: file
    file_path: /home/user/.homeassistant/sensor-data.txt

{% configuration %} file_path: description: Path to file that stores the sensor data. required: true type: string name: description: Name of the sensor to use in the frontend. required: false default: file name type: string unit_of_measurement: description: Defines the units of measurement of the sensor, if any. required: false type: string value_template: description: Defines a template to extract a value from the payload. required: false type: template {% endconfiguration %}

Examples

In this section you find some real-life examples of how to use this sensor.

Entries as JSON

Assuming that the log file contains multiple values formatted as JSON like shown below:

[...]
{"temperature": 21, "humidity": 39}
{"temperature": 22, "humidity": 36}

This would require the following entry in the configuration.yaml file to extract the temperature:

# Example configuration.yaml entry
sensor:
  - platform: file
    name: Temperature
    file_path: /home/user/.homeassistant/sensor.json
    value_template: {% raw %}'{{ value_json.temperature }}'{% endraw %}
    unit_of_measurement: '°C'