jhomeassistant 0.3.3

Framework for building easy Home Assistant devices

jhomeassistant

A Python library for Home Assistant MQTT device discovery based on jmqtt connections.

Installation

pip install jhomeassistant

Requirements

• Python >=3.8
• jmqtt
• python-slugify

Quickstart

from jmqtt import MQTTBuilderV3
from jhomeassistant import HomeAssistantConnection, HomeAssistantDevice
from jhomeassistant.entities import HomeAssistantEntityBase
from jhomeassistant.types import Component

# 1) Build MQTT connection
connection = (
    MQTTBuilderV3(host="localhost", app_name="my-tool")
    .instance_id("main")
    .availability("my-tool/status")
    .fast_build()
)

# 2) Wrap it for Home Assistant discovery
ha = HomeAssistantConnection(connection)
ha.origin.name = "my-tool"

# 3) Define an entity by subclassing HomeAssistantEntityBase
class TemperatureEntity(HomeAssistantEntityBase):
    def __init__(self):
        super().__init__(Component.SENSOR, "Temperature")

entity = TemperatureEntity()
device = HomeAssistantDevice("Kitchen Sensor").add_entities(entity)

# 4) Register and run discovery + scheduler loop
ha.add_devices(device)

# Blocking mode (current default behavior)
ha.run()

# Non-blocking mode with runtime handle (alternative)
# runtime = ha.run(blocking=False)
# print(runtime.is_running)
# runtime.stop(timeout=5.0)
# runtime.join(timeout=5.0)

Core Concepts

HomeAssistantConnection

• Holds a jmqtt connection (MQTTConnectionV3 or MQTTConnectionV5)
• Builds and publishes Home Assistant device discovery payloads
• Subscribes to homeassistant/status and dispatches birth/death hooks to entities

Main configuration:

• discovery_prefix("homeassistant")
• origin.name, origin.sw_version, origin.url
• availability (connection-level availability inheritance)
• qos, encoding (connection-level defaults inherited by devices)

HomeAssistantDevice

• Represents one Home Assistant device block in discovery
• Auto-detects runtime device facts using jmqtt.client_identity.facts
• Derives stable identifiers for discovery and entity unique IDs
• Supports prevent_device_merge=True to avoid connection-based merge identifiers

Common fields:

• manufacturer, model, model_id
• hw_version, sw_version
• via_device, configuration_url
• qos, encoding
• availability

HomeAssistantEntityBase

• Base class for entities that belong to a HomeAssistantDevice
• Provides deterministic identifier and discovery payload base
• Supports scheduled publisher functions via add_schedule(interval, function)
• Lifecycle hooks:
  • home_assistant_birth(connection)
  • home_assistant_death(connection)

Discovery Output

HomeAssistantConnection.discovery_text() returns formatted discovery topics + payloads, useful for debugging and tests.

Runtime Control

HomeAssistantConnection.run(...) supports both runtime styles:

• ha.run() or ha.run(blocking=True): runs discovery + HA status subscription + scheduler in the caller thread.
• runtime = ha.run(blocking=False): starts the same runtime in a background thread and returns HomeAssistantRuntime.

Runtime handle API:

• runtime.is_running
• runtime.last_error
• runtime.stop(timeout=...)
• runtime.join(timeout=...) -> bool

Notes

• origin.name is required by device-based discovery payload validation.
• If not set explicitly, device name is used as fallback.
• Entity names should be unique within a device to avoid unique_id collisions.

License

MIT (see LICENSE).