config.json.sample

{
    "sparkAccessToken": "",
    "sparkDeviceID": "",
    "twilioAccountSID": "",
    "twilioAuthToken": "",
    "toPhoneNumber": "[NUMBER TO CALL]",
    "fromPhoneNumber": "[YOUR TWILIO NUMBER]",
    "paperTowelTwiml": "[URL TO TWIML FILE. DROPBOX WORKS GREAT]"
}

congo-mash.ino

// A knock-off of the Amazon Dash product using a Spark Core, button, and NodeJS

int button = D0;  // Our button
int led = D7; // Really only used for testing to ensure button presses are registering

// This routine runs only once upon reset
void setup() {
  Spark.publish("online");
  pinMode(button, INPUT_PULLUP);  // Enable the internal pullup so no external resistors are required
  pinMode(led, OUTPUT);
}

// This routine gets called repeatedly, like once every 5-15 milliseconds.
// Spark firmware interleaves background CPU activity associated with WiFi + Cloud activity with your code. 
// Make sure none of your code delays or blocks for too long (like more than 5 seconds), or weird things can happen.
void loop() {
  // Check for a button press
  if(digitalRead(button) == LOW){
      digitalWrite(led, HIGH);
      Spark.publish("papertowels"); // This event causes the magic to happen in the monitor app
      delay(400);
      digitalWrite(led, LOW);
  }
}

monitor.js

var spark = require('sparknode');
var fs = require('fs');
//
// Config
//
if (!fs.existsSync('./config.json')) {
    console.error('Please create a config.json -- check config.json.sample');
    process.exit();
}

var config = require('./config.json');
var client = require('twilio')(config.twilioAccountSID, config.twilioAuthToken);

var core = new spark.Core({
  accessToken: config.sparkAccessToken,
  id: config.sparkDeviceID
});

core.on('online', function(){
  console.log("Congo Mash Button Online!");
});

// These are different events that can be fired by the configured buttons
core.on('papertowels', function(){
  client.makeCall({

      to:config.toPhoneNumber,
      from: config.fromPhoneNumber, // A number you bought from Twilio and can use for outbound communication
      url: config.paperTowelTwiml // A URL that produces an XML document (TwiML) which contains instructions for the call

  }, function(err, responseData) {

      //executed when the call has been initiated.
      console.log(responseData.from); // outputs your fromPhoneNumber
      if(err)
        console.log(err);
  });
})

core.on('error', function(data) {
    console.error('Error: ' + JSON.stringify(data));
});