FreeDATA/tnc.py

#!/usr/bin/env python3
# -*- coding: utf-8 -*-


import socketserver
import threading
import logging


import modem
import static
#from other import *
import other

modem = modem.RF()



class TCPRequestHandler(socketserver.BaseRequestHandler):

    def handle(self):
        
        # self.request is the TCP socket connected to the client
        self.data = self.request.recv(1024).strip()
        
     
        # interrupt listening loop "while true" by setting MODEM_RECEIVE to False
        #if len(self.data) > 0:
       #     static.MODEM_RECEIVE = False
        
        
        ####print("{} wrote:".format(self.client_address[0]))
        ####print(self.data)
        
        # just send back the same data, but upper-cased
        #####self.request.sendall(self.data.upper())
        
        #if self.data == b'TEST':
            #logging.info("DER TEST KLAPPT! HIER KOMMT DER COMMAND PARSER HIN!")

# BROADCAST PARSER  -----------------------------------------------------------

        if self.data.startswith(b'BC:'):
            static.MODEM_RECEIVE = True ####### FALSE....
            #print(static.MODEM_RECEIVE)
            
            data = self.data.split(b'BC:')
            daten = modem.Transmit(data[1])
            
            static.MODEM_RECEIVE = True
            #print(static.MODEM_RECEIVE)
            
            
            
# ACKNOWLEDGE PARSER  -----------------------------------------------------------

        if self.data.startswith(b'ACK:'):
            static.MODEM_RECEIVE = True ############## FALSE
            #print(static.MODEM_RECEIVE)
            
            data = self.data.split(b'ACK:')
            data_out = data[1]
            
            
            static.TX_BUFFER = [data_out[i:i+24] for i in range(0, len(data_out), 24)] # split incomming bytes to size of 30bytes, create a list and loop through it  
            static.TX_BUFFER_SIZE = len(static.TX_BUFFER)
            logging.info("TX | TOTAL PAYLOAD BYTES/FRAMES TO SEND: " + str(len(data_out)) + " / " + str(static.TX_BUFFER_SIZE))
            for frame in range(static.TX_BUFFER_SIZE): # LOOP THROUGH DATA LIST
                
                #--------------------------------------------- BUILD DATA PACKET
                ack = b'REQACK'
                data_to_transmit = ack + static.TX_BUFFER[frame]
               
                logging.info("TX | SENDING FRAME " + str(frame+1) + " / " + str(static.TX_BUFFER_SIZE))
                #---------------------------------------------------------------    
        
            
                #--------------------------------------------- ATTEMPTS TO SEND A MESSAGE IF ACK FAILS
                for static.TX_N_RETRIES in range(static.TX_N_MAX_RETRIES):
                    
                    # --------------------------- SEND FRAME
                    static.ACK_RECEIVED = 0
                    daten = modem.Transmit(data_to_transmit)
                    
                    # --------------------------- START TIMER ---> IF TIMEOUT REACHED, ACK_TIMEOUT = 1
                    static.ACK_TIMEOUT = 0
                    timer = threading.Timer(static.ACK_TIMEOUT_SECONDS, other.timeout)
                    timer.start() 

                    # --------------------------- WHILE TIMEOUT NOT REACHED AND NO ACK RECEIVED --> LISTEN
                    logging.info("TX | WAITING FOR ACK")

                    while static.ACK_TIMEOUT == 0 and static.ACK_RECEIVED == 0:
                        static.MODEM_RECEIVE = True   
                    
                    #--------------- BREAK LOOP IF ACK HAS BEEN RECEIVED
                    if static.ACK_RECEIVED == 1:
                        static.TX_N_RETRIES = 3
                        break
                    

                #-------------------------BREAK TX BUFFER LOOP IF ALL PACKETS HAVE BEEN SENT
                if frame == static.TX_BUFFER_SIZE:
                    break
                        
            logging.info("TX | BUFFER EMPTY")