add button control

.gitignore

@@ -1,3 +1,5 @@
+service/config.json
+
 # Byte-compiled / optimized / DLL files
 __pycache__/
 *.py[cod]

README.md

@@ -1,3 +1,22 @@
 # iot-raspberry-pi-controller
 
-Control relay(s) with a Raspberry Pi.  Should run as a system service and update the relay state(s) based on messages via MQTT or physical momentary switch(es).
+Control relay(s) with a Raspberry Pi.  Should run as a system service and update the relay state(s) based on messages via MQTT/AMQP or physical momentary switch(es).
+
+## Setup
+
+### Configuration
+
+Place populated `config.json` next to `main.py` with configured values.  See `config.sample.json` for what this should look like.
+
+### System service
+
+Copy `iot-raspberry-pi-controller.service` to `/etc/systemd/system` and then run `sudo systemctl start iot-raspberry-pi-controller.service`.  If satisfied, enable it with `sudo systemctl enable iot-raspberry-pi-controller.service`.  The service can be stopped at any time by running `sudo systemctl stop iot-raspberry-pi-controller.service`.
+
+## Todo
+
+- set up messaging via RabbitMQ
+  - consume messages to toggle relay channels
+  - publish messages with latest status of relay channels
+- add output logging of switch state changes and around RabbitMQ messages
+- look into how to properly package this for easier installation/deployment (thinking about installing python dependencies)
+- tests??

config.sample.json

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+{
+    "relay": {
+        "channels": [
+            {
+                "name": "Outdoor Light",
+                "key": "outdoor-light",
+                "pin": 13
+            },
+            {
+                "name": "East Wall Switch",
+                "key": "east-wall-switch",
+                "pin": 26
+            },
+            {
+                "name": "West Wall Switch",
+                "key": "west-wall-switch",
+                "pin": 6
+            },
+            {
+                "name": "3D Printer",
+                "key": "3d-printer",
+                "pin": 5
+            }
+        ]
+    },
+    "buttons": [
+        {
+            "name": "Outdoor Light",
+            "key": "outdoor-light",
+            "pin": 0
+        },
+        {
+            "name": "3D Printer",
+            "key": "3d-printer",
+            "pin": 0
+        }
+    ],
+    "rabbitmq": {}
+}

raspberry-pi-relay-controller.service

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+[Unit]
+Description=Raspberry Pi Relay Controller
+After=network.target
+
+[Service]
+ExecStart=/usr/bin/python3 -u service/main.py
+WorkingDirectory=/home/pi/iot-raspberry-pi-controller
+StandardOutput=inherit
+StandardError=inherit
+Restart=always
+User=pi
+
+[Install]
+WantedBy=multi-user.target

service/button.py

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+from gpiozero import Button as GPIOButton
+import time
+
+class Button:
+  _gpio_button = None
+  _debounce_time = 500
+  _last_press = 0
+  _channel = None
+
+
+  def __init__(self, name, key, pin):
+    self.name = name
+    self.key = key
+    self._pin = pin
+
+    self._setup()
+
+  def set_relay_channel(self, channel):
+    self._channel = channel
+
+  def _pressed(self):
+    press_time = self._current_millis()
+
+    if(self._is_outside_of_debounce(press_time)):
+      if(self._channel is not None):
+        self._channel.toggle()
+        self._last_press = press_time
+
+  def _setup(self):
+    self._gpio_button = GPIOButton(self._pin)
+    self._gpio_button.when_released = self._pressed
+
+  def _is_outside_of_debounce(self, press_time):
+    return press_time - self._last_press > self._debounce_time
+
+  def _current_millis(self):
+    return round(time.time() * 1000)

service/main.py

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+import json
+import signal
+
+from relay import Relay
+from button import Button
+
+def load_config():
+  with open('config.json') as f:
+    return json.load(f)
+
+# parse config
+config = load_config()
+
+
+# set up relay
+relay = Relay()
+for val in config['relay']['channels']:
+  relay.add_channel(val['name'], val['key'], val['pin'])
+
+
+# set up buttons
+buttons = []
+for button_config in config['buttons']:
+  button = Button(button_config['name'], button_config['key'], button_config['pin'])
+  button.set_relay_channel(relay.get_channel(button_config['key']))
+
+  buttons.append(button)
+
+
+# todo(chrisjacob): set up RabbitMQ
+# set up RabbitMQ
+
+signal.pause()

service/rabbitmq.py

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+import pika
+
+class RabbitMQ:
+  def __init__(self, connection_string, relay):
+    # todo (chrisjacob): build this out

service/relay.py

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+from gpiozero import LED
+import time
+import logging
+
+class Channel:
+  _pin = None
+  _output = None
+
+  _debounce_time = 500
+  _last_press = 0
+
+  def __init__(self, name, pin):
+    self.name = name
+    self.pin = pin
+
+    self._output = LED(pin)
+
+  def get_state(self):
+    self._output.is_active
+
+  def turn_on(self):
+    if(not self.safety_enabled() and self._is_outside_of_debounce(self._current_millis())):
+      self._last_press = self._current_millis()
+      self._output.on()
+
+  def turn_off(self):
+    # no debounce here, we can always turn it off
+    self._output.off()
+
+  def toggle(self):
+    if(not self.safety_enabled() and self._is_outside_of_debounce(self._current_millis())):
+      self._last_press = self._current_millis()
+      self._output.toggle()
+
+  def _is_outside_of_debounce(self, press_time):
+    return press_time - self._last_press > self._debounce_time
+
+  def _current_millis(self):
+    return round(time.time() * 1000)
+
+    def _safety_enabled(self):
+      # todo(chrisjacob): return true if channel has changed state more than _x_ times in _n_ seconds
+
+class Relay:
+  _channels = {}
+
+  def add_channel(self, name, key, pin):
+    self._channels[key] = Channel(name, pin)
+
+  def get_channel(self, key):
+    return self._channels[key]
+
+  def turn_on(self, key):
+    if(self._channels.has_key(key)):
+      self._channels[key].turn_on()
+
+  def turn_off(self, key):
+    if(self._channels.has_key(key)):
+      self._channels[key].turn_off()
+
+  def toggle(self, key):
+    if(self._channels.has_key(key)):
+      self._channels[key].toggle()