serverSide.py

import socket
import random
import threading
import json
import os
"""
Serverska strana jednostavne aplikacije za razmenu fajlova

"""
"""
Primer izgleda koriscenog recnika
"""
# korisnici = {
#     "korisnik1":{
#         "password":"fon123",
#         "files":[
#         "Gq37zTq432",
#         "mX6A1njGxZ",
#         ]
#     },
#     "korisnik2":{
#         "password":"fon321",
#         "files":[
#         "Gq37zTq432",
#         "mX6A1njGxZ",
#         ]
#     },
# }
"""
Obavezno ucitavanje json datoteke radi koriscenja
recnika korisnici
"""
def json_in(path):
    if os.path.isfile(path):
        with open(path, 'r') as q:
            data = q.read()
        return json.loads(data)
    else:
        return {}

korisnici = json_in('db/korisnici.json')
aktivni_korisnici = []
"""
Registracija novih korisnika
"""
def add_new_user(sock):
    username = sock.recv(1024)

    while username.decode('ascii') in korisnici.keys():
        sock.send("ERR".encode('ascii'))
        username = sock.recv(1024)
    sock.send("OK".encode('ascii'))

    p = sock.recv(1024)

    while p.decode('ascii') == "":
        sock.send("ERR".encode('ascii'))
        p = sock.recv(1024)

    sock.send("OK".encode('ascii'))
    username = username.decode('ascii')
    password = p.decode('ascii')
    new_dic = {'password': password, 'files': []}
    korisnici[username] = new_dic
    #Automatski se vrsi log in
    aktivni_korisnici.append(username)
    extract(korisnici)




"""
Generator jedinstvenog koda od deset karaktera(A-Z,a-z,0-9)
"""
def code_generator():
    letters = "abcdefghijklmnopqrstuvwxyz"
    upper_letters = letters.upper()
    numbers = "0123456789"
    sequence = letters + upper_letters + numbers
    code = ''
    for i in range(10):
        code += random.choice(sequence)
    return code

"""
Ekstrakcija recnika u JSON file.
"""
def extract(recnik):
    with open("db/korisnici.json",'w') as f:
        f.write(json.dumps(recnik,indent=2))

"""
Preuzimanje fajlova
"""
def download(sock):
    code = sock.recv(1024).decode('ascii')

"""
Funkcija za upload novog fajla
"""
def upload(sock):
    text = sock.recv(1024).decode('ascii')
    while not text:
        sock.send("ERR".encode('ascii'))
        text = sock.recv(1024).decode('ascii')
    sock.send("OK".encode('ascii'))
    code = code_generator()
    sock.send(code.encode('ascii'))
    with open('db/files/' + code,'wb') as f:
        f.write(text.encode('ascii'))
    username = sock.recv(1024).decode('ascii')
    korisnici[username]['files'].append(code)
    extract(korisnici)

"""
Forma za logovanje
"""
def log_in(sock):
    username = sock.recv(1024).decode('ascii')

    while not username in korisnici.keys():
        sock.send("ERR".encode('ascii'))
        username = sock.recv(1024).decode('ascii')
    sock.send("OK".encode('ascii'))

    password = sock.recv(1024).decode('ascii')
    while password != korisnici[username]['password']:
        sock.send("ERR".encode('ascii'))
        password = sock.recv(1024).decode('ascii')
    sock.send("OK".encode('ascii'))
    aktivni_korisnici.append(username)


"""
Funkcija koja vrsi navigaciju kroz aplikaciju{interface}
"""
def interfejs(sock):
    #Da li zelite download ili upload? Unesite d ili u
    userInput = sock.recv(1024)
    if userInput.decode('ascii') in ['d','D']:
        download(sock)
    elif userInput.decode('ascii') in ['u','U']:
        response = sock.recv(1024)
        if response.decode('ascii') in ['l','L']:
            log_in(sock)
        elif response.decode('ascii') in ['n','N']:
            add_new_user(sock)
        else:
            sock.send("ERR".encode('ascii'))
        upload(sock)
    else:
        sock.send("ERR".encode('ascii'))

def main():
    host = socket.gethostname()
    port = 10000

    s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
    s.bind((host,port))

    s.listen(5)

    print("Server osluskuje")
    while True:
        c, addr = s.accept()
        print("Konektovao se korisnik sa adresom: >>>{}".format(addr))
        t = threading.Thread(target=upload, args=(c,))
        t.start()

    s.close()

if __name__ == '__main__':
    main()