core.py

#!/usr/bin/env python
"""
Heart of the Bier-Automat. Will connect to the LegiLeser and decide if you get a beer.
is also responsible for starting all the (future) fancy stuff
"""

import MySQLdb as mdb
import ConfigParser
import datetime as dt
import legireader
import amivid
import visid
import os.path
import urllib

debug = True

def amivAuth(rfid):
    """Checks if the user may get a beer sponsored by AMIV
    :param rfid: Legi-Code of user
    :returns: tuple (user,bool) where the first value says returns the user-login (or None) and the second if he may get a beer
    """
    #Connect to amivid and get user object
    aid = amivid.AmivID(apikey=config.get("amivid", "apikey"),secretkey=config.get("amivid", "secretkey"),baseurl=config.get("amivid", "baseurl"))
    user = aid.getUser(rfid)
    if not user:
        return(None,False)
    login = user['nethz']
    
    #Use login-name to check if he may get a beer 
    #Old: API-Query beer = aid.getBeer(login)
    #New: Take it from the user object
    beer = user['apps']
    
    #return result, first bool says if user was found, second if he may get a beer)
    if (debug): print "Debug: Beer-Count %s"%(beer['beer'])
    return (login,int(beer['beer']) > 0)
    
def visAuth(rfid):
    """Checks if the user may get a beer sponsored by AMIV
    :param rfid: Legi-Code of user
    :returns: tuple (user,bool) where the first value says returns the user-login (or None) and the second if he may get a beer
    """
    #Get secret key
    #config = ConfigParser.RawConfigParser()
    #config.readfp(open('core.conf'))
    
    #Connect to visid and get user object
    vid = visid.VisID(baseurl=config.get("visid", "baseurl"))
    user = vid.getUser(rfid)
    if not user:
        return(None,False)
    login = user['nethz']
    
    #Use login-name to check if he may get a beer 
    beer = vid.getBeer(login)
    
    #return result, first bool says if user was found, second if he may get a beer)
    return (login,int(beer['beer']) > 0)
    

def __getAuthorization(rfid):
    """Here later the real auth must be done, returning None, "AMIV", "VIS" or "MONEY" (or whatever)
    
    :param rfid: Integer holding the Legi-Card-Number
    :returns: Tuple of Username and auth. organization (can be 'noBeer') or (None,'notRegistered') if not registered
    """
    returnString = 'notRegistered'
    returnUser = None
    #Ask AMIV for auth
    aA = amivAuth(rfid)
    if aA[0]:
        if aA[1]:
            return (aA[0],'amiv')
        else:
            returnUser = aA[0]
            returnString = 'noBeer'
    #Ask VIS if not true from AMIV
    vA = visAuth(rfid)
    if vA[0]:
        if vA[1]:
            return (vA[0],'vis')
        else:
            returnUser = vA[0]
            returnString = 'noBeer'

    return (returnUser,returnString)
    

def sendToScreen(var, value):
    """Sends a value using POST to the local (flask) server, used to communicate with the GUI"""
    serverUrl = "http://localhost:5000/_checkLegi"
    request = {var: value}
    try:
        reply = urllib.urlopen(serverUrl+"?"+urllib.urlencode(request)).read()
    except IOError:
        print "Could not connect to local webserver"
        return
    if (debug): print "sendToScreen with %s: %s, reply was %s"%(var,value,reply)


def showCoreMessage(page, code=None, sponsor=None, user=None):
    """Displays a HTML-page on the Display in the core-part, showing the basic info if a legi was accepted"""
    if page == 'authorized':
        #Template for sending the info to the display
        #sendToScreen('beerState','authorized')        
        print "%s authorized by %s, press the button!"%(user,sponsor)
        
    if page == 'notAuthorized':
        print "Not authorized, user was: %s"%(user)
        
    if page == 'notRegistered':
        print "Not registered, legi was: %s"%(code)
        
    if page == 'freeBeer':
        print "%s got a free beer, sponsored by %s"%(user,sponsor)

def startApp(appname):
    """Starts a custom app"""
    pass
        

if __name__ == "__main__":
    debug = True
    
    #Load Config Parameters
    config = ConfigParser.RawConfigParser()
    config.readfp(open(os.path.dirname(__file__) + '/core.conf')) #changed this as well because not right directory otherwise (Fadri)
    
    dbuser = config.get("mysql", "user")
    dbpass = config.get("mysql", "pass")
    dbdatabase = config.get("mysql", "db")
    dbtable = config.get("mysql", "table")
    dbhost = config.get("mysql", "host")
    
    print "ConfigFile core.conf read"

    #Connect to Log-DB
    conn = mdb.connect(dbhost,dbuser,dbpass,dbdatabase)
    cursor = conn.cursor()
    
    #Initialize connection to LegiLeser
    lr = legireader.LegiReader() #Also accepts device, baud and waittime parameters
    
    print "Connection to LegiReader established"
    
    authorize = None
    lastUser = 0
    lastUserTime = dt.datetime.min
    
    #Start endless-loop
    try:
        while 1:
            #Wait for new Legi or Button, read it
            #print "Waiting for User Input (reading a Legi)"
            (legi,button) = lr.getLegiOrButton()
            
            #print "Detected User Input - Legi=%s, Button=%s"%(legi,button)
            
            #check if legi may get a beer
            if legi:
                #For debug: Time the auth-query
                #starttime = dt.datetime.now()
                authorize = __getAuthorization(legi)
                #print "Auth-Time: %s"%(dt.datetime.now()-starttime)
    
                if authorize[1] == 'amiv' or authorize[1] == 'vis':
                    showCoreMessage('authorized',sponsor=authorize[1],user=authorize[0])
                    lastUserTime = dt.datetime.now()
                    lastUser = authorize[0]
                    #Activate free beer
                    lr.setFreeBeer()
                elif authorize[1] == 'noBeer':
                    showCoreMessage('notAuthorized',user=authorize[0])
                elif authorize[1] == 'notRegistered':
                    showCoreMessage('notRegistered',code=legi)
                else:
                    print >>sys.stderr, "Authorization failed"

            elif button and authorize:
                #A Button was pressed, check if a legi was read in the last two seconds
                if (dt.datetime.now()-lastUserTime < dt.timedelta(seconds=5)):
                    #Show that a free beer was server
                    showCoreMessage('freeBeer',sponsor=authorize[1],user=authorize[0])
                    #Log it
                    queryString = "INSERT INTO %s(username, org, time, slot) VALUES (%%s,%%s,NOW(),%%s)"%(dbtable)
                    cursor.execute(queryString,
                                   (lastUser,authorize[1], button))
                    #Un-Authorize user
                    authorize = None
                    
            else:
                #Something else happened, send it to the Debug-Output and continue
                if (debug): print "Did not detect anything useful while reading"
                continue
    finally:
        #Process crashed or it was terminated, close open connections
        if (debug): print "Program stopped, cleaning up..."
        cursor.close()
        conn.close()