An Introduction to IoT (Internet of Toilets)

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const { RaspiIO } = require('raspi-io');
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const five = require('johnny-five');
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// Initialize a new Raspberry Pi Board
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const board = new five.Board({
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   io: new RaspiIO(),
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});
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// Wait for the board to initialize then start reading in input from sensors
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board.on('ready', () => {
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   // Initialize a new switch on the 16th GPIO Input pin
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   const spdt = new five.Switch('GPIO16');
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   // Wait for the open event to get triggered by the sensor
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   spdt.on('open', () => {
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      enterMaintenceMode();
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   });
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   // Recalibrate the box once the sensor has closed
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   // Once the box has been cleaned, the box prepares for a new event
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   spdt.on('close', () => {
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      console.log('close');
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      // When the box has been closed again
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      // wait 1 min for the box to settle
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      // and recalibrate a new base weight
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      setTimeout(() => {
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            scale.calibrate();
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      }, 60000);
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   });
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});
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board.on('fail', error => {
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   handleError(error);
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});

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#! /usr/bin/python2
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import time
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import sys
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import RPi.GPIO as GPIO
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from hx711 import HX711
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# Infintely run a loop that checks the weight every 1/10 of a second
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while True:
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   try:
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      # Prints the weight - and send it to the parent Node process
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      val = hx.get_weight()
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      print(val)
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      # Read the weight every 1/10 of a second
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      time.sleep(0.1)
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   except (KeyboardInterrupt, SystemExit):
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      cleanAndExit()

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const spawn = require('child_process').spawn;
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class Scale {
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   constructor(client) {
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      // Spin up the child process when the Scale is initialized
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      this.process = spawn('python', ['./hx711py/scale.py'], {
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            detached: true,
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      });
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   }
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   getWeight() {
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      // Takes stdout data from Python child script which executed
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      // with arguments and send this data to res object
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      this.process.stdout.on('data', data => {
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            // The data is returned from the Python process as a string
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            // We need to parse it to a float
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            this.currWeight = parseFloat(data);
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            // If a cat is present - do something
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            if (this.isCatPresent() {
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               this.handleCatInBoxEvent();
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            }
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      });
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      this.process.stderr.on('data', err => {
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            handleError(String(err));
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      });
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      this.process.on('close', (code, signal) => {
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            console.log(
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               `child process exited with code ${code} and signal ${signal}`
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            );
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      });
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   }
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   [...]
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}
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module.exports = Scale;

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const MongoClient = require('mongodb').MongoClient;
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const uri = 'YOUR MONGODB URI HERE'
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const client = new MongoClient(uri, { useNewUrlParser: true });
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client.connect(err => {
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   const collection = client.db('IoT').collection('toilets');
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   // perform actions on the collection object
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   client.close();
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});

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{
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   "_id": { "$oid": "dskfjlk2j92121293901233" },
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   "timestamp_day": { "$date": { "$numberLong": "1573854434214" } },
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   "type": "cat_in_box",
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   "cat": { "name": "BMO", "weight": "200" },
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   "owner": "Joe Karlsson",
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   "events": [
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         {
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            "timestamp_event": { "$date": { "$numberLong": "1573854435016" } },
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            "weight": { "$numberDouble": "15.593333333" }
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      },
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      {
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            "timestamp_event": { "$date": { "$numberLong": "1573854435824" } },
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            "weight": { "$numberDouble": "15.132222222" }
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      },
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      {
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            "timestamp_event": { "$date": { "$numberLong": "1573854436632"} },
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            "type": "maintenance"
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      }
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   ]
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}