Source Code - Pi-Lock

A Look into the Source Code behind Pi-Lock

Reading the RFID tags

This method opens the Raspberry Pi’s serial port, and loops continuously to read a RFID card/tag. It is the primary method of the Pi-Lock, and starts when the RPi boots up. If a card is found, it calls the findTag() function, which in turn searches in the local SQLite database (table: seguridad_permisos) for the card, and then determines if the scanned card if valid for entry.

Note

Check the configuration.py file for configuring the serial port variables. The .conf signifies a variable inside this file.

conf.ser.open()                                           # Open serial port

def readCard():
    try:
        LED("blue")                                       # Turn on Blue LED
        while True:                                       # Loop until card is scanned   
            conf.ser.flushInput()                         # Clean out the serial port
            LED("blue")
            rfidData = conf.ser.readline().strip()        # Read input and format
            print "Line: "
            if len(rfidData) > 0:                            
                rfidData = rfidData[1:13]                 # Get digits 1 to 13 of input
                print "Card Scanned: ", rfidData
                print findTag(rfidData)                   # Call findTag method, check database

    except:
        errorLog.classErrorLog(sys.exc_info())            # Log the error in the ErrorLog class

    finally:
        conf.ser.close()                                  # Close serial port
        conf.db.close()                                   # Close SQLite database
        RPIO.cleanup()                                    # Cleanup GPIO pins

conf.ser.open() # Open serial port

def readCard():

try:

LED("blue") # Turn on Blue LED

while True: # Loop until card is scanned

conf.ser.flushInput() # Clean out the serial port

LED("blue")

rfidData = conf.ser.readline().strip() # Read input and format

print "Line: "

if len(rfidData) > 0:

rfidData = rfidData[1:13] # Get digits 1 to 13 of input

print "Card Scanned: ", rfidData

print findTag(rfidData) # Call findTag method, check database

except:

errorLog.classErrorLog(sys.exc_info()) # Log the error in the ErrorLog class

finally:

conf.ser.close() # Close serial port

conf.db.close() # Close SQLite database

RPIO.cleanup() # Cleanup GPIO pins

Turning on a LED

A simple method to switch the LEDs’ color state. The parameter colorOn directs which light to turn on, thereby switching off the remaining two colors. The conf.GREEN, conf.RED, conf.BLUE variables are set in the configuration.py file, where each value represents a GPIO pin, set as an integer. In this instance, GREEN = 4, RED = 17 and BLUE = 22.

def LED(colorON):
        if colorON == "green":                         # if parameter is 'green'
            RPIO.output(conf.GREEN, True)              # Set green GPIO pin = True  / On
            RPIO.output(conf.RED, False)               # Set red GPIO pin   = False / Off
            RPIO.output(conf.BLUE, False)              # Set blue GPIO pin  = False / Off
            time.sleep(1)

        elif colorON == "red":
            RPIO.output(conf.GREEN, False)
            RPIO.output(conf.RED, True)
            RPIO.output(conf.BLUE, False)
            time.sleep(1)

        elif colorON == "blue":
            RPIO.output(conf.GREEN, False)
            RPIO.output(conf.RED, False)
            RPIO.output(conf.BLUE, True)

        else:
            return "Error"                               # Error if parameter is wrong

def LED(colorON):

if colorON == "green": # if parameter is 'green'

RPIO.output(conf.GREEN, True) # Set green GPIO pin = True / On

RPIO.output(conf.RED, False) # Set red GPIO pin = False / Off

RPIO.output(conf.BLUE, False) # Set blue GPIO pin = False / Off

time.sleep(1)

elif colorON == "red":

RPIO.output(conf.GREEN, False)

RPIO.output(conf.RED, True)

RPIO.output(conf.BLUE, False)

time.sleep(1)

elif colorON == "blue":

RPIO.output(conf.GREEN, False)

RPIO.output(conf.RED, False)

RPIO.output(conf.BLUE, True)

else:

return "Error" # Error if parameter is wrong

Check if card is permitted to enter

def findTag(inputTag):
    permiso = classPermiso(inputTag)

    entry = classEntradaLog(permiso)
    entry.postSQLite(), entry.postJSON()

    if currentDay is 7: dateIsSunday = True
    else: dateIsSunday = False

    if permiso.permission == conf.PERMISSION_YES:
        if (permiso.endHour > currentTime > permiso.startHour) or (permiso.startHour is None and permiso.endHour is None):
            if currentDate < permiso.endDate:
                if ((dateIsSunday is True) and permiso.sundayPermission == 1) or (dateIsSunday is False):
                    entry = classEntradaLog(permiso)
                    entry.postSQLite(), entry.postJSON()
                    LED("green")
                    time.sleep(1)
                    return "Access Granted"
                else:
                    LED("red")
                    entry = classEntradaLog(permiso)
                    entry.postSQLite(), entry.postJSON()
                    time.sleep(1)
                    return "Cannot enter on a Sunday"
            else:
                LED("red")
                entry = classEntradaLog(permiso)
                entry.postSQLite(), entry.postJSON()
                time.sleep(1)
                return "Date is too old"
        else:
            LED("red")
            entry = classEntradaLog(permiso)
            entry.postSQLite(), entry.postJSON()
            time.sleep(1)
            return "You are not permitted to enter at this Time"

    elif permiso.permission == conf.PERMISSION_NO:
        entry = classEntradaLog(permiso)
        entry.postSQLite(), entry.postJSON()
        LED("red")
        time.sleep(1)
        return "Access Denied"

    elif permiso.permission == conf.PERMISSION_BLACKLIST:
        entry = classEntradaLog(permiso)
        entry.postSQLite(), entry.postJSON()
        LED("red")
        time.sleep(1)
        return "!!! Alert !!!"

    elif permiso.permission == conf.PERMISSION_PIN:
        if (permiso.endHour > currentTime > permiso.startHour) or (permiso.startHour is None and permiso.endHour is None):
            if currentDate < permiso.endDate:
                if ((dateIsSunday is True) and permiso.sundayPermission == 1) or (dateIsSunday is False):
                    entry = classEntradaLog(permiso)
                    entry.postSQLite(), entry.postJSON()
                    #pinInput(permiso.personPIN)
                else:
                    entry = classEntradaLog(permiso)
                    entry.postSQLite(), entry.postJSON()
                    return "Cannot enter on a Sunday"
            else:
                entry = classEntradaLog(permiso)
                entry.postSQLite(), entry.postJSON()
                return "Date is too old"
        else:
            entry = classEntradaLog(permiso)
            entry.postSQLite(), entry.postJSON()
            return "You are not permitted to enter at this Time"
    else:
        entry = classEntradaLog(permiso)
        entry.postSQLite(), entry.postJSON()
        return "Unkown Permission"

def findTag(inputTag):

permiso = classPermiso(inputTag)

entry = classEntradaLog(permiso)

entry.postSQLite(), entry.postJSON()

if currentDay is 7: dateIsSunday = True

else: dateIsSunday = False

if permiso.permission == conf.PERMISSION_YES:

if (permiso.endHour > currentTime > permiso.startHour) or (permiso.startHour is None and permiso.endHour is None):

if currentDate < permiso.endDate:

if ((dateIsSunday is True) and permiso.sundayPermission == 1) or (dateIsSunday is False):

entry = classEntradaLog(permiso)

entry.postSQLite(), entry.postJSON()

LED("green")

time.sleep(1)

return "Access Granted"

else:

LED("red")

entry = classEntradaLog(permiso)

entry.postSQLite(), entry.postJSON()

time.sleep(1)

return "Cannot enter on a Sunday"

else:

LED("red")

entry = classEntradaLog(permiso)

entry.postSQLite(), entry.postJSON()

time.sleep(1)

return "Date is too old"

else:

LED("red")

entry = classEntradaLog(permiso)

entry.postSQLite(), entry.postJSON()

time.sleep(1)

return "You are not permitted to enter at this Time"

elif permiso.permission == conf.PERMISSION_NO:

entry = classEntradaLog(permiso)

entry.postSQLite(), entry.postJSON()

LED("red")

time.sleep(1)

return "Access Denied"

elif permiso.permission == conf.PERMISSION_BLACKLIST:

entry = classEntradaLog(permiso)

entry.postSQLite(), entry.postJSON()

LED("red")

time.sleep(1)

return "!!! Alert !!!"

elif permiso.permission == conf.PERMISSION_PIN:

if (permiso.endHour > currentTime > permiso.startHour) or (permiso.startHour is None and permiso.endHour is None):

if currentDate < permiso.endDate:

if ((dateIsSunday is True) and permiso.sundayPermission == 1) or (dateIsSunday is False):

entry = classEntradaLog(permiso)

entry.postSQLite(), entry.postJSON()

#pinInput(permiso.personPIN)

else:

entry = classEntradaLog(permiso)

entry.postSQLite(), entry.postJSON()

return "Cannot enter on a Sunday"

else:

entry = classEntradaLog(permiso)

entry.postSQLite(), entry.postJSON()

return "Date is too old"

else:

entry = classEntradaLog(permiso)

entry.postSQLite(), entry.postJSON()

return "You are not permitted to enter at this Time"

else:

entry = classEntradaLog(permiso)

entry.postSQLite(), entry.postJSON()

return "Unkown Permission"

Classes

Pi-Lock employs the use of a few object-oriented classes to make the source code more efficient, legible, and comprehensible. The classes are broken up into the following files:

EntryLog: Logs an entry in local SQLite db, and post data in JSON format to server
ErrorLog: Logs an error in local SQLite db
Permission: With the scanned RFID tag #, looks into local SQLite db for the matching information, and sets object’s instance variables to the record found, else to None
SystemStats
: Records and saves the RPi’s CPU temperature, and RAM, CPU and SD-card usage in JSON format

Class – Log an Entry

On initialization, the instance variables of the parameter permiso are passed on to the EntryLog class, and used for two actions: insert into the local SQLite db and post the JSON to a sever via HTTP protocol.

import json, datetime, sys
import piLock.configuration as conf
import classErrorLog as errorLog

class classEntradaLog:
    def __init__(self, permiso):                        # permiso is a class previously initialized in readRFID and passed on to this class 
        self.doorNumber = permiso.doorNumber
        self.rfidData = permiso.rfidTag
        self.personID = permiso.personID
        self.personName = permiso.personName
        self.curDT = str(datetime.datetime.now())
        self.permission = permiso.permission

    def postSQLite(self):
        try:
            with conf.db:
                if len(self.rfidData) == 12:
                    cur = conf.db.cursor()
                    queryString = "INSERT INTO seguridad_entrada(puerta_num, tarjeta_RFID, persona_SEQ, persona, fecha_hora, permiso) VALUES (?,?,?,?,?,?)"
                    cur.execute(queryString, (self.doorNumber, self.rfidData, self.personID, self.personName, self.curDT, self.permission))
                    
        except:
            errorLog.classErrorLog(sys.exc_info())

    def postJSON(self):
        jsonLog = [{'SEQ': self.doorNumber, 'puerta_num': self.doorNumber, 'tarjeta_RFID': self.rfidData, 'persona_SEQ': self.personID, 'persona': self.personName, 'fecha_hora': self.curDT, 'permiso': self.permission}]
        data_string = json.dumps(jsonLog)
        print 'JSON:', data_string

import json, datetime, sys

import piLock.configuration as conf

import classErrorLog as errorLog

class classEntradaLog:

def __init__(self, permiso): # permiso is a class previously initialized in readRFID and passed on to this class

self.doorNumber = permiso.doorNumber

self.rfidData = permiso.rfidTag

self.personID = permiso.personID

self.personName = permiso.personName

self.curDT = str(datetime.datetime.now())

self.permission = permiso.permission

def postSQLite(self):

try:

with conf.db:

if len(self.rfidData) == 12:

cur = conf.db.cursor()

queryString = "INSERT INTO seguridad_entrada(puerta_num, tarjeta_RFID, persona_SEQ, persona, fecha_hora, permiso) VALUES (?,?,?,?,?,?)"

cur.execute(queryString, (self.doorNumber, self.rfidData, self.personID, self.personName, self.curDT, self.permission))

except:

errorLog.classErrorLog(sys.exc_info())

def postJSON(self):

jsonLog = [{'SEQ': self.doorNumber, 'puerta_num': self.doorNumber, 'tarjeta_RFID': self.rfidData, 'persona_SEQ': self.personID, 'persona': self.personName, 'fecha_hora': self.curDT, 'permiso': self.permission}]

data_string = json.dumps(jsonLog)

print 'JSON:', data_string

Class – Search in DB for Scanned RFID #

When a card is scanned, the Permission Class is initialized, and the RFID tag # is passed through as a parameter. The RFID tag # is then used to search the local SQLite DB in the table seguridad_permisos using a "SELECT * FROM ..." query. If the query returns null, the permission variables are set to None, otherwise the information matching the tag # is saved to the class’ instance methods.

class classPermiso:
    def __init__(self, tag):
        self.rfidTag = tag
        try:
            with conf.db:
                c = conf.db.cursor()
                c.execute("SELECT * FROM %s WHERE (tarjeta_RFID=:x)" % conf.permisoTable, {"x": self.rfidTag})
                row = c.fetchone()

                if row is None:
                    self.tagRecognized = conf.NO
                    self.doorNumber = None
                    self.permission = conf.PERMISSION_NO
                    self.personID = self.personName = self.personPIN = self.personPhoto = None
                    self.startHour = "00:00:00"
                    self.endHour = "24:00:00"
                    self.sundayPermission = "0"
                    self.endDate = "2100-01-01"

                else:
                    self.tagRecognized = conf.YES
                    self.doorNumber = row[1]
                    self.personID = row[3]
                    self.personName = row[4]
                    self.personPIN = int(row[5])
                    self.permission = row[6]
                    self.sundayPermission = row[7]
                    self.startHour = row[8]
                    self.endHour = row[9]
                    self.endDate = row[10]

        except:
            errorLog.classErrorLog(sys.exc_info())

class classPermiso:

def __init__(self, tag):

self.rfidTag = tag

try:

with conf.db:

c = conf.db.cursor()

c.execute("SELECT * FROM %s WHERE (tarjeta_RFID=:x)" % conf.permisoTable, {"x": self.rfidTag})

row = c.fetchone()

if row is None:

self.tagRecognized = conf.NO

self.doorNumber = None

self.permission = conf.PERMISSION_NO

self.personID = self.personName = self.personPIN = self.personPhoto = None

self.startHour = "00:00:00"

self.endHour = "24:00:00"

self.sundayPermission = "0"

self.endDate = "2100-01-01"

else:

self.tagRecognized = conf.YES

self.doorNumber = row[1]

self.personID = row[3]

self.personName = row[4]

self.personPIN = int(row[5])

self.permission = row[6]

self.sundayPermission = row[7]

self.startHour = row[8]

self.endHour = row[9]

self.endDate = row[10]

except:

errorLog.classErrorLog(sys.exc_info())

Class – Log an Error

When an error occurs, it is important to log it. Rather than simply make a .log file, Pi-Lock opts to write each error in the SQLite db. The error log is detailed and records the error type, message, line number, file name and string of the line on which the error occurred.

import linecache, datetime, os, sys
import piLock.configuration as conf

class classErrorLog:
    def __init__(self, sysError):
        self.eType, self.eObj, self.eTB = sysError
        f = self.eTB.tb_frame
        self.lineNumber = self.eTB.tb_lineno
        self.fileName = os.path.split(f.f_code.co_filename)[1]
        linecache.checkcache(self.fileName)
        self.errorType = self.eType.__name__
        self.errorMsg = self.eObj
        self.lineStr = linecache.getline(self.fileName, self.lineNumber, f.f_globals).strip()

    def insertDbError(self):
        try:
            db = conf.sqlite3.connect(conf.dbPath)
            with db:
                cur = db.cursor()
                query = "INSERT INTO %s VALUES(:SEQ, :fecha, :error, :msj, :archivo, :linea, :cont)"
                insert = {'SEQ':conf.SEQ, 'fecha':datetime.datetime.now(), 'error': self.errorType, 'msj':self.errorMsg, 'archivo':self.fileName, 'linea':self.lineNumber, 'cont':self.lineStr}
                cur.execute(query % conf.errorTable, insert)
        except:
            classErrorLog(sys.exc_info())

import linecache, datetime, os, sys

import piLock.configuration as conf

class classErrorLog:

def __init__(self, sysError):

self.eType, self.eObj, self.eTB = sysError

f = self.eTB.tb_frame

self.lineNumber = self.eTB.tb_lineno

self.fileName = os.path.split(f.f_code.co_filename)[1]

linecache.checkcache(self.fileName)

self.errorType = self.eType.__name__

self.errorMsg = self.eObj

self.lineStr = linecache.getline(self.fileName, self.lineNumber, f.f_globals).strip()

def insertDbError(self):

try:

db = conf.sqlite3.connect(conf.dbPath)

with db:

cur = db.cursor()

query = "INSERT INTO %s VALUES(:SEQ, :fecha, :error, :msj, :archivo, :linea, :cont)"

insert = {'SEQ':conf.SEQ, 'fecha':datetime.datetime.now(), 'error': self.errorType, 'msj':self.errorMsg, 'archivo':self.fileName, 'linea':self.lineNumber, 'cont':self.lineStr}

cur.execute(query % conf.errorTable, insert)

except:

classErrorLog(sys.exc_info())