FitbitIntraday.py

''' Module FitbitIntraday contains a class used to retrieve only the fitbit
intraday step, calorie, floor and time_active data. This data is collected as
xml files and returned or stored to disk'''

import cookielib
from datetime import datetime, timedelta
import os
from urllib import urlencode
import urllib2


class FitbitIntraday:
    '''
    FitbitIntraday is a class for retrieving the 5 minute intraday data from
    the fitbit.com website. For all other data requests you should use the
    official fitbit API: http://dev.fitbit.com/

    This utility will login as the user using the supplied credentials then it
    can be used to scrape and store the raw xml responses containing the user
    data. Supported data types are: steps, calories, floors, and time_active.
    '''

    def __init__(self):
        self.cookiej = cookielib.CookieJar()
        cookie_processor = urllib2.HTTPCookieProcessor(self.cookiej)
        self.opener = urllib2.build_opener(cookie_processor)

        self.chart_types = {
            'steps': ('intradaySteps', 'column2d'),
            'calories': ('intradayCaloriesBurned', 'column2d'),
            'floors': ('intradayAltitude', 'column2d'),
            'time_active': ('activitiesBreakdown', 'pie')
        }

    def login(self, email, password):
        '''Process a login to the fitbit website so we can collect appropriate
         cookies to retrieve data. Assumes both email and password are properly
         escaped strings'''

        auth_url = 'https://www.fitbit.com/login'
        payload = {
            'login': 'Log In',
            'includeWorkflow': '',
            'loginRedirect': 'redirect',
            'email': email,
            'password': password
        }
        encoded_data = urlencode(payload)
        request_object = urllib2.Request(auth_url, encoded_data)

        #Request the url with our posted login. We now have session cookies
        response = self.opener.open(request_object)
        return response

    def fetch_chart_data(self, data_type, chart_date):
        '''fetch chart data for a specified data. Allows types defined in the
        chart_types dictionary: steps, calories, floors, time_active.'''

        delta = timedelta(days=1)
        from_date = datetime.strftime(chart_date, "%Y-%m-%d")
        to_date = datetime.strftime(chart_date + delta, "%Y-%m-%d")

        request_string_parts = [
            'http://www.fitbit.com/graph/getGraphData?type=',
            self.chart_types[data_type][0],
            '&version=amchart&dateFrom=',
            from_date,
            '&dateTo=',
            to_date,
            '&chart_type=',
            self.chart_types[data_type][1]
        ]

        request_string = ''.join(request_string_parts)
        request = urllib2.Request(request_string)
        response = self.opener.open(request)

        return response

    def fetch_range_to_folder(self, data_type, path, from_date, to_date):
        '''utility function that repetatively calls fetch_chart_data over a
        range of dates for one of the 4 valid data types.'''

        delta = timedelta(days=1)
        current_day = from_date
        typed_path = os.path.join(path,data_type)

        if not os.path.exists(typed_path):
            os.makedirs(typed_path)

        while(current_day <= to_date):
            day_string = datetime.strftime(current_day, "%Y_%m_%d.xml")
            file_handle = open(os.path.join(typed_path,day_string), 'w')
            chart_data = self.fetch_chart_data(data_type, current_day)
            file_handle.write(chart_data.read())
            file_handle.close()
            current_day += delta