Watches bitcoin price at Bitstamp and sends alerts.

bitcoin-watch.py

import json
import time
import urllib2
from decimal import Decimal

import smtplib

# Amount of percentage highest bitcoin bid order can change in time_window
# If this is exceeded, alert is called
TOTAL_CHANGE_THRESHOLD = 10

# Amount of percentage highest bitcoin bid order can change between the last 2
# checkpoints. If this is exceeded, alert is called
RECENT_CHANGE_THRESHOLD = 4

# Time in seconds
TIME_WINDOW = 60 * 20
WATCH_INTERVAL = 30

SEND_TEST_MAIL_ON_START = True
MAIL_SERVER = 'posti.saunalahti.fi'
MAIL_RECEIVERS = receivers = ['[email protected]']

TICKER_URL = 'http://www.bitstamp.net/api/ticker/'


def alert(change, time_window):
    formatted_change = '%.2f %%' % change
    sender = '[email protected]'
    receivers = MAIL_RECEIVERS

    message = """From: Bitcoin alert <[email protected]>
To: All <[email protected]>
Subject: Bitcoin course has changed %s!

Total change was %s in %s seconds.
    """ % (formatted_change, formatted_change, time_window)

    try:
        smtpObj = smtplib.SMTP(MAIL_SERVER)
        smtpObj.sendmail(sender, receivers, message)
        print "Successfully sent email"
    except smtplib.SMTPException as e:
        print e
        print "Error: unable to send email"


def bitstamp_ticker():
    response = json.loads(urllib2.urlopen(TICKER_URL).read())
    for x, y in response.items():
        response[x] = Decimal(y)
    return response


def total_change_percentage(history):
    if len(history) < 2:
        return 0

    return (history[-1]['bid'] / history[0]['bid'] - 1) * 100


def total_time_window(history):
    if len(history) < 2:
        return 0

    return history[-1]['timestamp'] - history[0]['timestamp']


def recent_change_percentage(history):
    if len(history) < 2:
        return 0

    return (history[-1]['bid'] / history[-2]['bid'] - 1) * 100


def recent_time_window(history):
    if len(history) < 2:
        return 0

    return history[-1]['timestamp'] - history[-2]['timestamp']


def filter_old(history):
    return [x for x in history if x['timestamp'] >= time.time() - TIME_WINDOW]


def main():

    if SEND_TEST_MAIL_ON_START:
        alert(100, 100)

    history = []

    while True:
        ticker = bitstamp_ticker()
        history.append(ticker)
        history = filter_old(history)

        total_change = total_change_percentage(history)
        total_window = total_time_window(history)

        recent_change = recent_change_percentage(history)
        recent_window = recent_time_window(history)

        alert_sent = False
        if abs(total_change) > TOTAL_CHANGE_THRESHOLD:
            alert(total_change, time_window=total_window)
            alert_sent = True

        if abs(recent_change) > RECENT_CHANGE_THRESHOLD and not alert_sent:
            alert(recent_change, time_window=recent_window)

        print 'Currently highest bid price is %s USD' % ticker['bid']
        print 'Total change was %.2f %% in %s seconds' % (total_change,
            total_window)
        print 'Recent change was %.2f %% in %s seconds' % (recent_change,
            recent_window)

        time.sleep(WATCH_INTERVAL)



if __name__ == '__main__':
    main()