bug fix

import os

import datetime

config = None

def printWithTimeStamp(s):

def log(s):

    ms = int(datetime.datetime.now().microsecond / 1000)

    ms = '%03d' % ms

    print('[' + time.strftime('%Y-%m-%d %H:%M:%S', time.localtime(time.time())) + '.' + ms + '] ' + s)

    #May cause errors when string s contains unicode characters

def newConfig():

#Set up new config using default settings

    username=input('Username: ')

    passwd=input('Password: ')

    f=open('config.json','w')

    config={"username": str(username), "password": str(passwd), "testUrl": "http://www.v2ex.com/generate_204", "interval_retry_connection": "30", "interval_retry_login": "30", "interval_check_status": "60", "max_times_retry_login": "5"}

    f.write(json.dumps(config))

    f.close()

    printWithTimeStamp('Configurations successfully saved.')    

def readConfig():

    try:

        f=open('config.json')

        try:

            initconfig=json.loads(f.readline())

            config={"username": initconfig['username'], "password": initconfig['password'], "testUrl": initconfig['testUrl'], "interval_retry_connection": int(initconfig['interval_retry_connection']), "interval_retry_login": int(initconfig['interval_retry_login']), "interval_check_status": int(initconfig['interval_check_status']), "max_times_retry_login": int(initconfig['max_times_retry_login'])}

            #Check if the parameters all exist and transform format

        except KeyError as kerr:

            printWithTimeStamp('Parameter '+str(kerr)+' not found.')

            printWithTimeStamp('Configuration file is broken. Create a new one.')

            f.close()

            os.remove('config.json')

            newConfig()

        except ValueError as verr:

            printWithTimeStamp('Parameter '+str(verr)+' is invalid.')

            printWithTimeStamp('Configuration file is broken. Create a new one.')

            f.close()

            os.remove('config.json')

            newConfig()

    except PermissionError as err:

        sys.exit(err)

    return config

def loadConfig():

    if os.path.isfile('config.json'):

        return readConfig()

    else:

        printWithTimeStamp('No configuration file found.')

        newConfig()

        return readConfig()

def load_config():

    global config

    with open('config.json') as f:

        config = json.load(f)

    return config

def main():

    printWithTimeStamp("Program started.")

    log("Program started.")

    os.chdir(os.path.dirname(sys.argv[0]))  # To read config in the same directory

    printWithTimeStamp('Reading configurations...')

    config=loadConfig()

    log('Reading configurations...')

    config = load_config()

    times_retry_login = config['max_times_retry_login']

    printWithTimeStamp('Configurations successfully imported.')

    log('Configurations successfully imported.')

    while True:

        printWithTimeStamp('Checking network status...')

        log('Checking network status...')

        try:

            login = requests.Session()

            test = login.get(config['testUrl'])

        except:

            printWithTimeStamp('Connection FAILED. Try again in '+str(config['interval_retry_connection'])+' sec.')

            log('Connection FAILED. Try again in ' + str(config['interval_retry_connection']) + ' sec.')

            sleep(config['interval_retry_connection'])

            continue

        while test.status_code != 204:

            printWithTimeStamp('You are offline. Starting login...')

            printWithTimeStamp('Start to get login information')

            log('You are offline. Starting login...')

            log('Start to get login information')

            start = test.text.find(r'action') + 8

            end = test.text.find(r'" method="post"')

            action = test.text[start:end]

            log('action= ' + action + ';')

            start = test.text.find(r'name="lt"') + 17

            end=start+50

            lt=test.text[start:end]

            lt = test.text[start:]

            end = lt.find(r'" />')

            lt = lt[0:end]

            # Get parameter "lt"

            log('lt= ' + lt + ';')

            start = test.text.find(r'name="execution"') + 24

            end=start+10

            execution=test.text[start:end]

            execution = test.text[start:]

            end = execution.find(r'" />')

            execution = execution[0:end]

            # Get parameter "execution"

            log('execution= ' + execution + ';')

            start = test.text.find(r'name="_eventId"') + 23

            end = start + 10

            end = _eventId.find(r'" />')

            _eventId = _eventId[0:end]

            # Get parameter "_eventld"

            printWithTimeStamp('Login information acquired.')

            print('_eventId= ' + _eventId + ';')

            log('Login information acquired.')

            url = 'http://weblogin.sustc.edu.cn' + action

            username = config['username']

            passwd=config['password']

            password = config['password']

            # SUSTC CAS username (StudentID) and password

            data='username='+username+'&password='+passwd+'&lt='+lt+'&execution='+execution+'&_eventId='+_eventId+'&submit=LOGIN'

            data = 'username=' + username + '&password=' + password + '&lt=' + lt + '&execution=' + execution + '&_eventId=submit&submit=LOGIN'

            h={'Host': 'weblogin.sustc.edu.cn', 'Connection': 'keep-alive', 'Cache-Control': 'max-age=0', 'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8', 'Origin': 'http://weblogin.sustc.edu.cn', 'Upgrade-Insecure-Requests': '1', 'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/49.0.2623.112 Safari/537.36', 'Content-Type': 'application/x-www-form-urlencoded', 'DNT': '1', 'Referer': url, 'Accept-Encoding': 'gzip, deflate', 'Accept-Language': 'en-US,en;q=0.8,zh-CN;q=0.6,zh;q=0.4'}

            h = {'Host': 'weblogin.sustc.edu.cn', 'Connection': 'keep-alive', 'Cache-Control': 'max-age=0',

                 'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8',

                 'Origin': 'http://weblogin.sustc.edu.cn', 'Upgrade-Insecure-Requests': '1',

                 'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/49.0.2623.112 Safari/537.36',

                 'Content-Type': 'application/x-www-form-urlencoded', 'DNT': '1', 'Referer': url,

                 'Accept-Encoding': 'gzip, deflate', 'Accept-Language': 'en-US,en;q=0.8,zh-CN;q=0.6,zh;q=0.4'}

            printWithTimeStamp('Login as '+username)

            log('Login as ' + username)

            login.post(url, data=data, headers=h)

            printWithTimeStamp('Login information posted to the CAS server.')

            log('Login information posted to the CAS server.')

            test = requests.get(config['testUrl'])

            if test.status_code != 204:

                times_retry_login -= 1

                if times_retry_login > 0:  # If keep trying to login too many times, it may trigger security alarm on the CAS server

                    printWithTimeStamp('Login FAILED. Try again in '+str(config['interval_retry_login'])+' sec. '+str(times_retry_login)+r' attempt(s) remaining.')

                    log(

                        'Login FAILED. Try again in ' + str(config['interval_retry_login']) + ' sec. ' + str(

                            times_retry_login) + r' attempt(s) remaining.')

                else:

                    printWithTimeStamp('Login FAILED.' +r'Attempts used up. The program will quit.')

                    log('Login FAILED.' + r'Attempts used up. The program will quit.')

                    sys.exit('Login FAILED')

                sleep(config['interval_retry_login'])

            else:

                printWithTimeStamp('Login successful. Current user: '+username)

                log('Login successful. Current user: ' + username)

                times_retry_login = config['max_times_retry_login']

                printWithTimeStamp('Login attempts reseted to '+str(times_retry_login)+' .')

        printWithTimeStamp('Online. Re-check status in '+str(config['interval_check_status'])+' sec.')    

                log('Login attempts reset to ' + str(times_retry_login) + ' .')

        log('Online. Re-check status in ' + str(config['interval_check_status']) + ' sec.')

        sleep(config['interval_check_status'])

if __name__ == '__main__':

    main()