twitterb.py

# -*- coding: utf-8 -*-º
#!/usr/bin/python

# This is a Python port of Adafruit's "Gutenbird" sketch for Arduino.
# Polls one or more Twitter accounts for changes, displaying updates
# on attached thermal printer.
# Written by Adafruit Industries.  MIT license.
#
# Required hardware includes an Internet-connected system with Python
# (such as Raspberry Pi) and an Adafruit Mini Thermal Receipt printer
# and all related power supplies and cabling.
# Required software includes Adafruit_Thermal and PySerial libraries.
#
# Resources:
# http://www.adafruit.com/products/597 Mini Thermal Receipt Printer
# http://www.adafruit.com/products/600 Printer starter pack
#
# Uses Twitter 1.1 API application-only authentication.  This
# REQUIRES a Twitter account and some account configuration.  Start
# at dev.twitter.com, sign in with your Twitter credentials, select
# "My Applications" from the avatar drop-down menu at the top right,
# then "Create a new application."  Provide a name, description,
# placeholder URL and complete the captcha, after which you'll be
# provided a "consumer key" and "consumer secret" for your app.
# Copy these strings to the globals below, and configure the search
# string to your liking.  DO NOT SHARE your consumer key or secret!
# If you put code on Github or other public repository, replace them
# with dummy strings.

from __future__ import print_function
import base64, HTMLParser, httplib, json, sys, urllib, zlib
from unidecode import unidecode
from Adafruit_Thermal import *

import RPi.GPIO as IO
import time
import os

# Configurable globals.  Edit to your needs. -------------------------------

# Twitter application credentials -- see notes above -- DO NOT SHARE.
consumer_key    = os.environ['CONSUMER_KEY']
consumer_secret = os.environ['CONSUMER_SECRET']

# queryString can be any valid Twitter API search string, including
# boolean operators.  See http://dev.twitter.com/docs/using-search
# for options and syntax.  Funny characters do NOT need to be URL
# encoded here -- urllib takes care of that.
queryString = 'amor'


# Other globals.  You probably won't need to change these. -----------------

printer   = Adafruit_Thermal("/dev/serial0", 19200, timeout=5)
host      = 'api.twitter.com'
authUrl   = '/oauth2/token'
searchUrl = '/1.1/search/tweets.json?'
agent     = 'Gutenbird v1.0'
# lastID is command line value (if passed), else 1

if len(sys.argv) > 1: lastId = sys.argv[1]
else:                 lastId = '1'

# Initiate an HTTPS connection/request, uncompress and JSON-decode results
def issueRequestAndDecodeResponse(method, url, body, headers):
  connection = httplib.HTTPSConnection(host)
  connection.request(method, url, body, headers)
  response = connection.getresponse()
  if response.status != 200:
    # This is OK for command-line testing, otherwise
    # keep it commented out when using main.py
    # print('HTTP error: %d' % response.status)
    exit(-1)
  compressed = response.read()
  connection.close()
  return json.loads(zlib.decompress(compressed, 16+zlib.MAX_WBITS))


# Mainline code. -----------------------------------------------------------


def start_printing():
    # LED configuration
    IO.setmode(IO.BOARD)

    IO.setup(33, IO.OUT)
    IO.setup(31, IO.OUT)
    IO.setup(29, IO.OUT)


    # Get access token. --------------------------------------------------------
    token = issueRequestAndDecodeResponse(
      'POST', authUrl, 'grant_type=client_credentials',
       {'Host'            : host,
        'User-Agent'      : agent,
        'Accept-Encoding' : 'gzip',
        'Content-Type'    : 'application/x-www-form-urlencoded;charset=UTF-8',
        'Authorization'   : 'Basic ' + base64.b64encode(
         urllib.quote(consumer_key) + ':' + urllib.quote(consumer_secret))}
      )['access_token']


    # Perform search. ----------------------------------------------------------
    IO.output(33, True)
    time.sleep(1)
    data = issueRequestAndDecodeResponse(
      'GET',
      (searchUrl + 'count=3&since_id=%s&q=%s' %
       (lastId, urllib.quote(queryString))),
      None,
      {'Host'            : host,
       'User-Agent'      : agent,
       'Accept-Encoding' : 'gzip',
       'Authorization'   : 'Bearer ' + token})

    IO.output(33, False)

    # Display results. ---------------------------------------------------------

    maxId = data['search_metadata']['max_id_str']

    # Printer LED on
    IO.output(31, True)
    time.sleep(1)
    for tweet in data['statuses']:

      printer.inverseOn()
      printer.print(' ' + '{:<31}'.format(tweet['user']['screen_name']))
      printer.inverseOff()

      printer.underlineOn()
      printer.print('{:<32}'.format(tweet['created_at']))
      printer.underlineOff()

      # max_id_str is not always present, so check tweet IDs as fallback
      id = tweet['id_str']
      if(id > maxId): maxId = id # String compare is OK for this

      # Remove HTML escape sequences
      # and remap Unicode values to nearest ASCII equivalents
      printer.print(unidecode(
        HTMLParser.HTMLParser().unescape(tweet['text'])))

      printer.feed(3)

    # Printer LED off
    IO.output(31, False)
    

    time.sleep(5)
    IO.output(29, True)
    time.sleep(3)
    IO.output(29, False)

    IO.cleanup()

    print(maxId) # Piped back to calling process
    time.sleep(10)


while True:
    start_printing()