85 lines
1.8 KiB
Python
85 lines
1.8 KiB
Python
#!/usr/bin/python
|
|
|
|
import sys
|
|
from datetime import datetime
|
|
import time
|
|
import RPi.GPIO as IO
|
|
import zmq
|
|
|
|
# Magic numbers for PWM activation
|
|
MOTOR_PIN = 19
|
|
FREQUENCY = 100
|
|
DUTYCYCLE = 100
|
|
DURATION = 1.0
|
|
# Address of the scanning service
|
|
SCANSERVADDRESS = "tcp://localhost:5000"
|
|
|
|
|
|
def timestamped(s):
|
|
"""
|
|
Prepends a timestamp to a string.
|
|
"""
|
|
return "[{:%Y-%m-%d %H:%M:%S}] {}".format(datetime.now(), s)
|
|
|
|
def setup_pwm():
|
|
"""
|
|
Performs initialization for pulse width modulation.
|
|
Returns the PWM object for the motor pin.
|
|
"""
|
|
IO.setwarnings(False)
|
|
IO.setmode(IO.BCM)
|
|
IO.setup(MOTOR_PIN, IO.OUT)
|
|
p = IO.PWM(MOTOR_PIN, FREQUENCY)
|
|
return p
|
|
|
|
def unlock_door(p):
|
|
"""
|
|
Uses PWM to turn the motor connected to the door handle.
|
|
"""
|
|
try:
|
|
p.start(DUTYCYCLE)
|
|
xtime.sleep(DURATION)
|
|
finally:
|
|
p.stop()
|
|
|
|
def read_loop():
|
|
"""
|
|
Simple REPL skeleton for validating scanned IDs.
|
|
"""
|
|
# Initialize zmq socket for reading in scanned barcodes
|
|
context = zmq.Context()
|
|
socket = context.socket(zmq.SUB)
|
|
socket.setsockopt(zmq.SUBSCRIBE, "")
|
|
socket.connect(SCANSERVADDRESS)
|
|
# TODO: Open the access database
|
|
|
|
# Initialize the PWM pin for opening the door
|
|
pwm_pin = setup_pwm()
|
|
# Open the log file in append mode
|
|
log_file = open("./access.log", "a")
|
|
log_file.write(timestamped("=== Door security initiated ===\n"))
|
|
|
|
# Begin the loop
|
|
while True:
|
|
# Read in the ID
|
|
scanned_id = socket.recv()
|
|
# TODO: Check if the ID is authorized
|
|
authorized = True
|
|
|
|
|
|
# If the user is not authorized, deny access
|
|
if not authorized:
|
|
s = timestamped("##### denied\n")
|
|
log_file.write(s)
|
|
# If the user is authorized, perform the unlock procedure
|
|
else:
|
|
s = timestamped("##### <Username> validated\n")
|
|
log_file.write(s)
|
|
print s,
|
|
# TODO: Play open tone
|
|
# TODO: Run unlock procedure
|
|
unlock_door(pwm_pin)
|
|
|
|
if __name__ == "__main__":
|
|
read_loop()
|