import json
from typing import Any, Dict, Optional, cast, Union
from typing_extensions import override
from masterpiece.mqtt import Mqtt, MqttMsg
from masterpiece import MasterPiece, URL
from .timeutils import timestamp
[docs]
class Juham(MasterPiece):
"""Base class for automation objects with MQTT networking.
To configure the class to use a specific MQTT set
the `mqtt_class_id` class attribute to desired
MQTT implementation. When instantiated the object will instantiate
the given MQTT object with it.
"""
mqtt_class_id: str = ""
write_attempts: int = 3
mqtt_root_topic: str = ""
mqtt_host: str = "localhost"
mqtt_port: int = 1883
def __init__(self, name: str = "") -> None:
"""Constructs new automation object with the given name, configured
MQTT network features.
Args:
name (str): name of the object
"""
super().__init__(name)
self.mqtt_client: Optional[Union[Mqtt, None]] = None
self.mqtt_topic_base: str = ""
self.mqtt_topic_control: str = ""
self.mqtt_topic_log: str = ""
[docs]
@override
def to_dict(self) -> Dict[str, Any]:
data: Dict[str, Any] = super().to_dict()
data["_base"] = {}
attributes = ["mqtt_host", "mqtt_port", "mqtt_root_topic"]
for attr in attributes:
if getattr(self, attr) != getattr(type(self), attr):
data["_base"][attr] = getattr(self, attr)
return data
[docs]
@override
def from_dict(self, data: Dict[str, Any]) -> None:
super().from_dict(data)
for key, value in data["_base"].items():
setattr(self, key, value)
[docs]
def initialize(self) -> None:
"""Initialize mqtt networking for use. This method must be called
after the object name has been set.
"""
self.init_mqtt(self.name)
[docs]
def init_topic_base(self) -> None:
url: URL = self.make_url()
self.mqtt_root_topic = self.root().make_url().get()[1:]
self.mqtt_topic_base = url.get()[1:]
self.mqtt_topic_control = self.mqtt_root_topic + "/control"
self.mqtt_topic_log = self.mqtt_root_topic + "/log"
[docs]
def make_topic_name(self, topic: str) -> str:
"""Make topic name for the object. The topic name
consists of the base name plus the given 'topic'.
Args:
topic (str): topic name
Returns:
str: mqtt topic name
"""
return f"{self.mqtt_root_topic}/{topic}"
[docs]
def init_mqtt(self, name: str) -> None:
"""Instantiates the configured MQTT object for networking. Calls `init_topic()`
to construct topic base name for the object, and instantiates the mqtt
client.
This method is called internally and typically there is no need to call it
from the application code.
Issues a warning if the :attr:`mqtt_class_id` has not
been configured, even though objects without a capability to communicate
are rather crippled.
"""
self.init_topic_base()
if Juham.mqtt_class_id == "":
self.warning(
f"Suscpicious configuration: no mqtt_class_id set for {self.name}:{self.get_class_id()}"
)
elif not Juham.find_class(Juham.mqtt_class_id):
self.error(
f"Couldn't create mqtt broker {Juham.mqtt_class_id}, class not imported"
)
else:
self.mqtt_client = cast(
Optional[Mqtt], MasterPiece.instantiate(Juham.mqtt_class_id, name)
)
if self.mqtt_client is not None:
self.mqtt_client.on_message = self.on_message
self.mqtt_client.on_connect = self.on_connect
self.mqtt_client.on_disconnect = self.on_disconnect
if (
self.mqtt_client.connect_to_server(self.mqtt_host, self.mqtt_port)
!= 0
):
self.error(
f"Couldn't connect to the mqtt broker at {self.mqtt_client.host}"
)
else:
self.debug(
f"{self.name} with mqtt broker {self.mqtt_client.name} connected to {self.mqtt_client.host}"
)
else:
self.error(f"Couldn't create mqtt broker {Juham.mqtt_class_id}")
[docs]
def subscribe(self, topic: str) -> None:
"""Subscribe to the given MQTT topic.
This method sets up the subscription to the specified MQTT topic and registers
the :meth:`on_message` method as the callback for incoming messages.
Args:
topic (str): The MQTT topic to subscribe to.
Example:
::
# configure
obj.subscribe('foo/bar')
"""
if self.mqtt_client:
self.mqtt_client.connected_flag = True
self.mqtt_client.subscribe(topic)
self.info(f"{self.name} subscribed to { topic}")
[docs]
def on_message(self, client: object, userdata: Any, msg: MqttMsg) -> None:
"""MQTT message notification on arrived message.
Called whenever a new message is posted on one of the
topics the object has subscribed to via subscribe() method.
This method is the heart of automation: here, derived subclasses should
automate whatever they were designed to automate. For example, they could switch a
relay when a boiler temperature sensor signals that the temperature is too low for
a comforting shower for say one's lovely wife.
For more information on this method consult MQTT documentation available
in many public sources.
Args:
client (obj): MQTT client
userdata (Any): application specific data
msg (object): The MQTT message
"""
if msg.topic == self.mqtt_topic_control:
m = json.loads(msg.payload)
if m["command"] == "shutdown" and self.mqtt_client:
self.mqtt_client.disconnect()
self.mqtt_client.loop_stop()
[docs]
def on_connect(self, client: object, userdata: Any, flags: int, rc: int) -> None:
"""Notification on connect.
This method is called whenever the MQTT broker is connected.
For more information on this method consult MQTT documentation available
in many public sources.
Args:
client (obj): MQTT client
userdata (Any): application specific data
flags (int): Consult MQTT
rc (int): See MQTT docs
"""
if self.mqtt_client:
self.mqtt_client.subscribe(self.mqtt_topic_control)
self.debug(self.name + " connected to the mqtt broker ")
[docs]
def on_disconnect(self, client: object, userdata: Any, rc: int = 0) -> None:
"""Notification on disconnect.
This method is called whenever the MQTT broker is disconnected.
For more information on this method consult MQTT documentation available
in many public sources.
Args:
client (obj): MQTT client
userdata (Any): application specific data
rc (int): See MQTT docs
"""
self.info(f"{self.name} disconnected from the mqtt broker, {rc} ")
[docs]
@override
def debug(self, msg: str, details: str = "") -> None:
"""Logs the given debug message to the database after logging it using
the BaseClass's info() method.
Args:
msg (str): The information message to be logged.
details (str): Additional detailed information for the message to be logged
"""
super().debug(msg, details)
self.log_message("Debug", msg, details="")
[docs]
@override
def info(self, msg: str, details: str = "") -> None:
"""Logs the given information message to the database after logging it
using the BaseClass's info() method.
Args:
msg : The information message to be logged.
details : Additional detailed information for the message to be logged
Example:
::
obj = new Base('test')
obj.info('Message arrived', str(msg))
"""
super().info(msg, details)
self.log_message("Info", msg, details="")
[docs]
@override
def warning(self, msg: str, details: str = "") -> None:
"""Logs the given warning message to the database after logging it
using the BaseClass's info() method.
Args:
msg (str): The information message to be logged.
details (str): Additional detailed information for the message to be logged
"""
super().warning(msg, details)
self.log_message("Warn", msg, details)
[docs]
@override
def error(self, msg: str, details: str = "") -> None:
"""Logs the given error message to the database after logging it using
the BaseClass's info() method.
Args:
msg (str): The information message to be logged.
details (str): Additional detailed information for the message to be logged
"""
super().error(msg, details)
self.log_message("Error", msg, details)
[docs]
def log_message(self, type: str, msg: str, details: str = "") -> None:
"""Publish the given log message to the MQTT 'log' topic.
This method constructs a log message with a timestamp, class type, source name,
message, and optional details. It then publishes this message to the 'log' topic
using the MQTT protocol.
Parameters:
type : str
The classification or type of the log message (e.g., 'Error', 'Info').
msg : str
The main log message to be published.
details : str, optional
Additional details about the log message (default is an empty string).
Returns:
None
Raises:
Exception
If there is an issue with the MQTT client while publishing the message.
Example:
::
# publish info message to the Juham's 'log' topic
self.log_message("Info", f"Some cool message {some_stuff}", str(dict))
"""
try:
lmsg: dict[str, Any] = {
"Timestamp": timestamp(),
"Class": type,
"Source": self.name,
"Msg": msg,
"Details": str(details),
}
self.publish(self.mqtt_topic_log, json.dumps(lmsg), 1)
except Exception as e:
if self._log is not None:
self._log.error(f"Publishing log event failed {str(e)}")
[docs]
def publish(self, topic: str, msg: str, qos: int = 1, retain: bool = True) -> None:
"""Publish the given message to the given MQTT topic.
For more information consult MQTT.
Args:
topic (str): topic
msg (str): message to be published
qos (int, optional): quality of service. Defaults to 1.
retain (bool, optional): retain. Defaults to True.
"""
if self.mqtt_client:
self.mqtt_client.publish(topic, msg, qos, retain)
[docs]
def shutdown(self) -> None:
"""Shut down all services, free resources, stop threads, disconnect
from mqtt, in general, prepare for shutdown."""
if self.mqtt_client:
self.mqtt_client.disconnect()
self.mqtt_client.loop_stop()
[docs]
@override
def run(self) -> None:
"""Start a new thread to runs the network loop in the background.
Allows the main program to continue executing while the MQTT
client handles incoming and outgoing messages in the background.
"""
self.initialize()
if self.mqtt_client:
self.mqtt_client.loop_start()
super().run()
[docs]
@override
def run_forever(self) -> None:
"""Starts the network loop and blocks the main thread, continuously
running the loop to process MQTT messages.
The loop will run indefinitely unless the connection is lost or
the program is terminated.
"""
self.initialize()
if self.mqtt_client:
self.info(f"{self.name} has mqtt client, calling forever...")
self.mqtt_client.loop_forever()
self.info(f"{self.name} mqtt client run_forever returned")
else:
self.error(
f"{self.name} does NOT have mqtt client, cannot run_forever, giving up"
)