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| 1 | +"""Support for Apache Kafka.""" |
| 2 | +from datetime import datetime |
| 3 | +import json |
| 4 | +import logging |
| 5 | + |
| 6 | +from aiokafka import AIOKafkaProducer |
| 7 | +import voluptuous as vol |
| 8 | + |
| 9 | +from homeassistant.const import ( |
| 10 | + CONF_IP_ADDRESS, CONF_PORT, EVENT_HOMEASSISTANT_STOP, EVENT_STATE_CHANGED, |
| 11 | + STATE_UNAVAILABLE, STATE_UNKNOWN) |
| 12 | +import homeassistant.helpers.config_validation as cv |
| 13 | +from homeassistant.helpers.entityfilter import FILTER_SCHEMA |
| 14 | + |
| 15 | +_LOGGER = logging.getLogger(__name__) |
| 16 | + |
| 17 | +DOMAIN = 'apache_kafka' |
| 18 | + |
| 19 | +CONF_FILTER = 'filter' |
| 20 | +CONF_TOPIC = 'topic' |
| 21 | + |
| 22 | +CONFIG_SCHEMA = vol.Schema({ |
| 23 | + DOMAIN: vol.Schema({ |
| 24 | + vol.Required(CONF_IP_ADDRESS): cv.string, |
| 25 | + vol.Required(CONF_PORT): cv.port, |
| 26 | + vol.Required(CONF_TOPIC): cv.string, |
| 27 | + vol.Optional(CONF_FILTER, default={}): FILTER_SCHEMA, |
| 28 | + }), |
| 29 | +}, extra=vol.ALLOW_EXTRA) |
| 30 | + |
| 31 | + |
| 32 | +async def async_setup(hass, config): |
| 33 | + """Activate the Apache Kafka integration.""" |
| 34 | + conf = config[DOMAIN] |
| 35 | + |
| 36 | + kafka = hass.data[DOMAIN] = KafkaManager( |
| 37 | + hass, |
| 38 | + conf[CONF_IP_ADDRESS], |
| 39 | + conf[CONF_PORT], |
| 40 | + conf[CONF_TOPIC], |
| 41 | + conf[CONF_FILTER]) |
| 42 | + |
| 43 | + hass.bus.async_listen(EVENT_HOMEASSISTANT_STOP, kafka.shutdown()) |
| 44 | + |
| 45 | + await kafka.start() |
| 46 | + |
| 47 | + return True |
| 48 | + |
| 49 | + |
| 50 | +class DateTimeJSONEncoder(json.JSONEncoder): |
| 51 | + """Encode python objects. |
| 52 | +
|
| 53 | + Additionally add encoding for datetime objects as isoformat. |
| 54 | + """ |
| 55 | + |
| 56 | + def default(self, o): # pylint: disable=E0202 |
| 57 | + """Implement encoding logic.""" |
| 58 | + if isinstance(o, datetime): |
| 59 | + return o.isoformat() |
| 60 | + return super().default(o) |
| 61 | + |
| 62 | + |
| 63 | +class KafkaManager: |
| 64 | + """Define a manager to buffer events to Kafka.""" |
| 65 | + |
| 66 | + def __init__( |
| 67 | + self, |
| 68 | + hass, |
| 69 | + ip_address, |
| 70 | + port, |
| 71 | + topic, |
| 72 | + entities_filter): |
| 73 | + """Initialize.""" |
| 74 | + self._encoder = DateTimeJSONEncoder() |
| 75 | + self._entities_filter = entities_filter |
| 76 | + self._hass = hass |
| 77 | + self._producer = AIOKafkaProducer( |
| 78 | + loop=hass.loop, |
| 79 | + bootstrap_servers="{0}:{1}".format(ip_address, port), |
| 80 | + compression_type="gzip", |
| 81 | + ) |
| 82 | + self._topic = topic |
| 83 | + |
| 84 | + def _encode_event(self, event): |
| 85 | + """Translate events into a binary JSON payload.""" |
| 86 | + state = event.data.get('new_state') |
| 87 | + if (state is None |
| 88 | + or state.state in (STATE_UNKNOWN, '', STATE_UNAVAILABLE) |
| 89 | + or not self._entities_filter(state.entity_id)): |
| 90 | + return |
| 91 | + |
| 92 | + return json.dumps( |
| 93 | + obj=state.as_dict(), |
| 94 | + default=self._encoder.encode |
| 95 | + ).encode('utf-8') |
| 96 | + |
| 97 | + async def start(self): |
| 98 | + """Start the Kafka manager.""" |
| 99 | + self._hass.bus.async_listen(EVENT_STATE_CHANGED, self.write) |
| 100 | + await self._producer.start() |
| 101 | + |
| 102 | + async def shutdown(self): |
| 103 | + """Shut the manager down.""" |
| 104 | + await self._producer.stop() |
| 105 | + |
| 106 | + async def write(self, event): |
| 107 | + """Write a binary payload to Kafka.""" |
| 108 | + payload = self._encode_event(event) |
| 109 | + |
| 110 | + if payload: |
| 111 | + await self._producer.send_and_wait(self._topic, payload) |
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