Validar un jid XMPP con python?

Question

¿Cuál es la forma correcta de validar un jid xmpp? La sintaxis se describe here:, pero realmente no lo entiendo. Además, parece bastante complicado, por lo que usar una biblioteca para hacerlo parece una buena idea.

Actualmente estoy usando xmpppy, pero parece que no encuentro cómo validar un jid con él. Cualquier ayuda apreciada!

Answer 1

En primer lugar, la mejor referencia actual para JID es RFC 6122.

que estaba a punto de darle la expresión regular aquí, pero dejé llevar un poco de distancia, y ejecutado la totalidad de la especificación:

import re 
import sys 
import socket 
import encodings.idna 
import stringprep 

# These characters aren't allowed in domain names that are used 
# in XMPP 
BAD_DOMAIN_ASCII = "".join([chr(c) for c in range(0,0x2d) + 
        [0x2e, 0x2f] + 
        range(0x3a,0x41) + 
        range(0x5b,0x61) + 
        range(0x7b, 0x80)]) 

# check bi-directional character validity 
def bidi(chars): 
    RandAL = map(stringprep.in_table_d1, chars) 
    for c in RandAL: 
     if c: 
      # There is a RandAL char in the string. Must perform further 
      # tests: 
      # 1) The characters in section 5.8 MUST be prohibited. 
      # This is table C.8, which was already checked 
      # 2) If a string contains any RandALCat character, the string 
      # MUST NOT contain any LCat character. 
      if filter(stringprep.in_table_d2, chars): 
       raise UnicodeError("Violation of BIDI requirement 2") 

      # 3) If a string contains any RandALCat character, a 
      # RandALCat character MUST be the first character of the 
      # string, and a RandALCat character MUST be the last 
      # character of the string. 
      if not RandAL[0] or not RandAL[-1]: 
       raise UnicodeError("Violation of BIDI requirement 3") 

def nodeprep(u): 
    chars = list(unicode(u)) 
    i = 0 
    while i < len(chars): 
     c = chars[i] 
     # map to nothing 
     if stringprep.in_table_b1(c): 
      del chars[i] 
     else: 
      # case fold 
      chars[i] = stringprep.map_table_b2(c) 
      i += 1 
    # NFKC 
    chars = stringprep.unicodedata.normalize("NFKC", "".join(chars)) 
    for c in chars: 
     if (stringprep.in_table_c11(c) or 
      stringprep.in_table_c12(c) or 
      stringprep.in_table_c21(c) or 
      stringprep.in_table_c22(c) or 
      stringprep.in_table_c3(c) or 
      stringprep.in_table_c4(c) or 
      stringprep.in_table_c5(c) or 
      stringprep.in_table_c6(c) or 
      stringprep.in_table_c7(c) or 
      stringprep.in_table_c8(c) or 
      stringprep.in_table_c9(c) or 
      c in "\"&'/:<>@"): 
      raise UnicodeError("Invalid node character") 

    bidi(chars) 

    return chars 

def resourceprep(res): 
    chars = list(unicode(res)) 
    i = 0 
    while i < len(chars): 
     c = chars[i] 
     # map to nothing 
     if stringprep.in_table_b1(c): 
      del chars[i] 
     else: 
      i += 1 
    # NFKC 
    chars = stringprep.unicodedata.normalize("NFKC", "".join(chars)) 
    for c in chars: 
     if (stringprep.in_table_c12(c) or 
      stringprep.in_table_c21(c) or 
      stringprep.in_table_c22(c) or 
      stringprep.in_table_c3(c) or 
      stringprep.in_table_c4(c) or 
      stringprep.in_table_c5(c) or 
      stringprep.in_table_c6(c) or 
      stringprep.in_table_c7(c) or 
      stringprep.in_table_c8(c) or 
      stringprep.in_table_c9(c)): 
      raise UnicodeError("Invalid node character") 

    bidi(chars) 

    return chars 

def parse_jid(jid): 
    # first pass 
    m = re.match("^(?:([^\"&'/:<>@]{1,1023})@)?([^/@]{1,1023})(?:/(.{1,1023}))?$", jid) 
    if not m: 
     return False 

    (node, domain, resource) = m.groups() 
    try: 
     # ipv4 address? 
     socket.inet_pton(socket.AF_INET, domain) 
    except socket.error: 
     # ipv6 address? 
     try: 
      socket.inet_pton(socket.AF_INET6, domain) 
     except socket.error: 
      # domain name 
      dom = [] 
      for label in domain.split("."): 
       try: 
        label = encodings.idna.nameprep(unicode(label)) 
        encodings.idna.ToASCII(label) 
       except UnicodeError: 
        return False 

       # UseSTD3ASCIIRules is set, but Python's nameprep doesn't enforce it. 
       # a) Verify the absence of non-LDH ASCII code points; that is, the 
       for c in label: 
        if c in BAD_DOMAIN_ASCII: 
         return False 
       # Verify the absence of leading and trailing hyphen-minus 
       if label[0] == '-' or label[-1] == "-": 
        return False 
       dom.append(label) 
      domain = ".".join(dom) 
    try: 
     if node is not None: 
      node = nodeprep(node) 
     if resource is not None: 
      resource = resourceprep(resource) 
    except UnicodeError: 
     return False 

    return node, domain, resource 

if __name__ == "__main__": 
    results = parse_jid(sys.argv[1]) 
    if not results: 
     print "FAIL" 
    else: 
     print results 

Sí, esto es un montón de trabajo. Hay buenas razones para todo esto, pero esperamos simplificarlo en el futuro si el grupo de trabajo précis da sus frutos.