testserverone.py

import socket
from zlib import crc32
from ReliableUDP import *
from http10 import *

SRC_ADDR, SRC_PORT = "localhost", 9999
server = "apache 2.0"
# SOCK_DGRAM is the socket type to use for UDP sockets
sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
sock.bind((SRC_ADDR, SRC_PORT))
client_connection = ClientConnectionInfo()

while True:
    client_connection.receive_data_buffer = []
    sock.settimeout(None)
    print("Server start...")
    packet, (DEST_ADDR, DEST_PORT) = sock.recvfrom(MAX_PACKET_SIZE)
    header = unpack(PACK_FORMAT, packet[:HEADER_LENGTH])
    checksum = header[0]
    num = header[1]
    ack = header[2]
    fin = header[3]
    more = header[4]
    packet = (
        pack(
            PACK_FORMAT,
            0,
            header[1],
            header[2],
            header[3],
            header[4],
        )
        + packet[HEADER_LENGTH:]
    )
    if (
        crc32(packet) == checksum
        and num == client_connection.num
        and not ack
        and not fin
    ):
        
        client_connection.receive_data_buffer.append(
            packet[HEADER_LENGTH:].decode())
        sock.settimeout(PACKET_LOSS_TIMEOUT)
        more = 1
        while more:
            try:
                response_packet = get_ack_packet(client_connection.num)
                sock.sendto(response_packet, (DEST_ADDR, DEST_PORT))
                packet, (DEST_ADDR, DEST_PORT) = sock.recvfrom(MAX_PACKET_SIZE)
                header = unpack(PACK_FORMAT, packet[:HEADER_LENGTH])
                checksum = header[0]
                num = header[1]
                ack = header[2]
                fin = header[3]
                more = header[4]

                packet = (
                    pack(
                        PACK_FORMAT,
                        0,
                        header[1],
                        header[2],
                        header[3],
                        header[4],
                    )
                    + packet[HEADER_LENGTH:]
                )
                if (
                    crc32(packet) != checksum
                    or num != client_connection.num
                    or fin
                ):
                    raise socket.timeout
                elif ack:
                    client_connection.num = not client_connection.num
                else:
                    client_connection.receive_data_buffer.append(
                        packet[HEADER_LENGTH:].decode()
                    )
                    client_connection.num = not client_connection.num

            except socket.timeout:
                sock.sendto(response_packet, (DEST_ADDR, DEST_PORT))
        complete_request = "".join(client_connection.receive_data_buffer)

        if complete_request[:3] == "GET":
            file_name = complete_request.split(" ")[1].replace("/", "")
            try:
                f = open(file_name, "r")
                status_code = 200
                status = "OK"
                file_content = f.read()
            except FileNotFoundError:
                print("File not found! Check the path variable and filename")
                status_code = 404
                status = "NOT FOUND"
                file_content = ""
            http_response = get_http_response(
                "GET", status_code, status, file_content, server
            )
        elif complete_request[:4] == "POST":
            http_response = get_http_response("POST", 200, "OK", "", server)

        client_connection.send_packets_buffer = get_packets(
            http_response, client_connection.num
        )

        while len(client_connection.send_packets_buffer):
            next_packet = client_connection.send_packets_buffer.pop(0)
            sock.sendto(next_packet, (DEST_ADDR, DEST_PORT))
            while True:

                try:
                    packet, (addr, port) = sock.recvfrom(MAX_PACKET_SIZE)
                    # check not corrupted
                    header = unpack(PACK_FORMAT, packet[:HEADER_LENGTH])
                    checksum = header[0]
                    num = header[1]
                    ack = header[2]
                    fin = header[3]

                    packet = (
                        pack(
                            PACK_FORMAT,
                            0,
                            header[1],
                            header[2],
                            header[3],
                            header[4],
                        )
                        + packet[HEADER_LENGTH:]
                    )

                    if crc32(packet) == checksum:
                        if num != client_connection.num or not ack or fin:
                            raise socket.timeout
                        client_connection.num = not client_connection.num
                        break
                    else:
                        raise socket.timeout  # resend last packet
                except socket.timeout:
                    sock.sendto(next_packet, (DEST_ADDR, DEST_PORT))
        print(complete_request)
    else:
        print("Invalid request!")