This is an Ubuntu Unity Indicator to track your Dorm internet usage in NTUST. Added manual update quota, changed html parser. Written on Python 2.7

ntust-dormweb-indicator.py

#!/usr/bin/env python
# -*- coding: utf8 -*-

import appindicator
import bs4
import datetime
import glib
import gtk
import logging
import pynotify
import re
import requests
import socket
import sys

logging.basicConfig(level=logging.DEBUG)
capabilities = {'actions':             False,
                'body':                False,
                'body-hyperlinks':     False,
                'body-images':         False,
                'body-markup':         False,
                'icon-multi':          False,
                'icon-static':         False,
                'sound':               False,
                'image/svg+xml':       False,
                'private-synchronous': False,
                'append':              False,
                'private-icon-only':   False}


def initCaps():
    caps = pynotify.get_server_caps()
    if caps is None:
        print "Failed to receive server caps."
        sys.exit(1)

    for cap in caps:
        capabilities[cap] = True


def printCaps():
    info = pynotify.get_server_info()
    print "Name:          " + info["name"]
    print "Vendor:        " + info["vendor"]
    print "Version:       " + info["version"]
    print "Spec. Version: " + info["spec-version"]

    caps = pynotify.get_server_caps()
    if caps is None:
        print "Failed to receive server caps."
        sys.exit(1)

    print "Supported capabilities/hints:"
    if capabilities['actions']:
        print "\tactions"
    if capabilities['body']:
        print "\tbody"
    if capabilities['body-hyperlinks']:
        print "\tbody-hyperlinks"
    if capabilities['body-images']:
        print "\tbody-images"
    if capabilities['body-markup']:
        print "\tbody-markup"
    if capabilities['icon-multi']:
        print "\ticon-multi"
    if capabilities['icon-static']:
        print "\ticon-static"
    if capabilities['sound']:
        print "\tsound"
    if capabilities['image/svg+xml']:
        print "\timage/svg+xml"
    if capabilities['private-synchronous']:
        print "\tprivate-synchronous"
    if capabilities['append']:
        print "\tappend"
    if capabilities['private-icon-only']:
        print "\tprivate-icon-only"

    print "Notes:"
    if info["name"] == "notify-osd":
        print "\tx- and y-coordinates hints are ignored"
        print "\texpire-timeout is ignored"
        print "\tbody-markup is accepted but filtered"
    else:
        print "\tnone"


class ThreadClass():
    def __init__(self, menu_items):
        self.__menu_items = menu_items
        self.__set_menu_message_default()
        self.__menu_items[4].set_label("Update now")
        self.__menu_items[4].connect("activate", self.updateQuota)
        self.__usage_alert = pynotify.Notification("NTUST Dormweb Indicator", "Your quota has reached 2.5 GB", "dialog-warning")

    def run(self):
        try:
            self.updateQuota("")
        except Exception:
            # if anything happen, just set the default message
            logging.exception("Something happened! Set default message..")
            self.__set_menu_message_default()
            ind.set_status(appindicator.STATUS_ATTENTION)
        finally:
            # set interval
            logging.debug("UPDATED " + datetime.datetime.now().strftime("%Y/%m/%d %H:%M:%S"))
            glib.timeout_add(300000, self.run)

    def updateQuota(self, w):
        date = datetime.datetime.now()
        # query IP address
        logging.debug("Querying IP address..")
        s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
        s.connect(("netweb.ntust.edu.tw", 80))
        ip = s.getsockname()[0]
        s.close()
        logging.debug("IP " + ip)

        # query usage
        logging.debug("Querying Usage..")
        usage = self.requestUsage(ip, date.strftime("%Y/%m/%d"))
        logging.debug(usage)

        if usage[0] > 2500000000:
            self.__usage_alert.show()
            ind.set_status(appindicator.STATUS_ATTENTION)
        else:
            ind.set_status(appindicator.STATUS_ACTIVE)

        self.__set_menu_message([
            ip,
            "{0:.2f}".format(usage[0] / 1000000) + " MB",
            "{0:.2f}".format(usage[1] / 1000000) + " MB",
            "{0:.2f}".format(usage[2] / 1000000) + " MB"
        ])

    def requestUsage(self, ip, datestring):
        # define post variables then request to netweb page
        payload = {"__EVENTTARGET": "ipdata",
                   "__EVENTARGUMENT": "",
                   "__VIEWSTATE": "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",
                   "RB_1": "詳細流量查詢",
                   "un": "Bytes",
                   "do_date": datestring,
                   "ipdata": ip,
                   "hip": re.sub('[0-9]+\.[0-9]+$', '', ip),
                   "msg_sysadm": "，請撥分機6212洽管理者！",
                   "p_ip": ip,
                   "dorm": "",
                   "pdate": datestring,
                   "page_size": "32760",
                   "sel_str": "dodate='*****'",
                   "tablename": "ipflowtable",
                   "tot_columns": "4",
                   "tot_rows": "0",
                   "tinsert": "",
                   "hmaxlen": "10,14,14,14,13,10,13,6,6,13,20,15,15,15,15",
                   "od_str": "",
                   "un_v": "1"}
        r = requests.post('http://netweb.ntust.edu.tw/dormweb/flowquery.aspx', data=payload)

        # response text to DOM using BeautifulSoup
        soup = bs4.BeautifulSoup(r.text, "html.parser")
        total = float(soup.find(id="tablelist__ctl3_tid1")["value"].replace(",", ""))
        upload = float(soup.find(id="tablelist__ctl3_tid2")["value"].replace(",", ""))
        download = float(soup.find(id="tablelist__ctl3_tid3")["value"].replace(",", ""))
        return [total, upload, download]

    def __set_menu_message_default(self):
        self.__set_menu_message(["N/A", "N/A", "N/A", "N/A"])

    def __set_menu_message(self, msg):
        self.__menu_items[0].set_label("Local address: " + msg[0])
        self.__menu_items[1].set_label("Total: " + msg[1])
        self.__menu_items[2].set_label("Upload: " + msg[2])
        self.__menu_items[3].set_label("Download: " + msg[3])


if __name__ == "__main__":
    if not pynotify.init("summary-body"):
        sys.exit(1)

    # call this so we can savely use capabilities dictionary later
    initCaps()

    # show what's supported
    printCaps()

    ind = appindicator.Indicator("ntust-dormweb-indicator",
                                 "nm-adhoc",
                                 appindicator.CATEGORY_APPLICATION_STATUS)
    ind.set_status(appindicator.STATUS_ACTIVE)
    ind.set_attention_icon("new-messages-red")

    # create a menu
    menu = gtk.Menu()

    # create some menu items
    menu_items = []
    for x in xrange(1, 6):
        menu_item = gtk.MenuItem()
        menu_items.append(menu_item)
        menu.append(menu_item)
        menu_item.show()

    # set the menu
    ind.set_menu(menu)

    # fire up the thread!
    t = ThreadClass(menu_items)
    t.run()

    gtk.main()