openhab-pythonrule-engine 1.0

Openhab python rule engine

OpenHab python rule engine

A python 3.x rule engine for OpenHAB. This rule engine allows defining rule by using python 3.x.

Please consider that the OpenHAB username/password auhentication (basic authentication) needs to be enabled in the org.openhab.restauth settings

To run this software you may use Docker or PIP package manager such as shown below

Docker approach

sudo docker run -e openhab_uri=http://192.168.1.17:8080 -e user=me -e pwd=secret -v /etc/openhab2/automation/rules/python:/rules grro/pythonrule_engine 

PIP approach

sudo pip install openhab-pythonrule-engine

After this installation you may start the rule engine inside your python code or via command line using

sudo pyrule --command listen --openhab_uri http://localhost:8080 --python_rule_directory /etc/openhab2/automation/rules/python --user me --pwd secret

Here, the rule engine will connect the openhab instance running on the local machine on port 8080. Furthermore, the directory /etc/openhab2/automation/rules/python will be used to scan for python-based rules

By running a systemd-based Linux distribution you may use the register command to register and start the rule engine as systemd unit. By doing this the rule engine will be started automatically on boot. Starting the server manually using the listen command is no longer necessary.

sudo pyrule --command register --openhab_uri http://localhost:8080 --python_rule_directory /etc/openhab2/automation/rules/python --user me --pwd secret

Rules

To trigger a rule methode the @when decorator will be used. Currently

• Cron expressions are supported as well as
• Item change trigger as shown below

If the method defines a (single!) argument, the item_registry object will be injected automatically. The item_registry cann be used to get item state as well as to update item state. By setting the state the data value will be auto converted into the item specific data type

Example: my_rule.py (located within /etc/openhab2/automation/rules/python)

from openhab_pythonrule_engine.condition import when
from openhab_pythonrule_engine.item_registry import ItemRegistry


@when('Time cron */1 * * * *')  # every 1 minute
@when('Item PhoneLisaLastSeen changed')
@when('Item PhoneJoeLastSeen changed')
def update_persence_based_on_phone_seen(item_registry: ItemRegistry):
    last_time_present = item_registry.get_state_as_datetime('LastDateTimePresence')
    for phone_name in item_registry.get_group_membernames('Phones'):
        last_seen = item_registry.get_state_as_datetime(phone_name)
        if last_seen > last_time_present:
            last_time_present = last_seen
    item_registry.set_state('LastDateTimePresence', last_time_present)