Add validate_email to utils

gettor/parse/email.py

@@ -15,7 +15,6 @@ from __future__ import absolute_import
 import re
 import dkim
 import hashlib
-import validate_email
 
 from datetime import datetime
 import configparser
@@ -29,6 +28,7 @@ from twisted.enterprise import adbapi
 
 from ..utils.db import SQLite3
 from ..utils import strings
+from ..utils import validate_email
 
 class AddressError(Exception):
     """

gettor/utils/validate_email.py

+# RFC 2822 - style email validation for Python
+# (c) 2012 Syrus Akbary <me@syrusakbary.com>
+# Extended from (c) 2011 Noel Bush <noel@aitools.org>
+# for support of mx and user check
+# This code is made available to you under the GNU LGPL v3.
+#
+# This module provides a single method, valid_email_address(),
+# which returns True or False to indicate whether a given address
+# is valid according to the 'addr-spec' part of the specification
+# given in RFC 2822.  Ideally, we would like to find this
+# in some other library, already thoroughly tested and well-
+# maintained.  The standard Python library email.utils
+# contains a parse_addr() function, but it is not sufficient
+# to detect many malformed addresses.
+#
+# This implementation aims to be faithful to the RFC, with the
+# exception of a circular definition (see comments below), and
+# with the omission of the pattern components marked as "obsolete".
+
+import re
+import smtplib
+import logging
+import socket
+
+try:
+    raw_input
+except NameError:
+    def raw_input(prompt=''):
+        return input(prompt)
+
+try:
+    import DNS
+    ServerError = DNS.ServerError
+    DNS.DiscoverNameServers()
+except (ImportError, AttributeError):
+    DNS = None
+
+    class ServerError(Exception):
+        pass
+
+# All we are really doing is comparing the input string to one
+# gigantic regular expression.  But building that regexp, and
+# ensuring its correctness, is made much easier by assembling it
+# from the "tokens" defined by the RFC.  Each of these tokens is
+# tested in the accompanying unit test file.
+#
+# The section of RFC 2822 from which each pattern component is
+# derived is given in an accompanying comment.
+#
+# (To make things simple, every string below is given as 'raw',
+# even when it's not strictly necessary.  This way we don't forget
+# when it is necessary.)
+#
+WSP = r'[\s]'                                        # see 2.2.2. Structured Header Field Bodies
+CRLF = r'(?:\r\n)'                                   # see 2.2.3. Long Header Fields
+NO_WS_CTL = r'\x01-\x08\x0b\x0c\x0f-\x1f\x7f'        # see 3.2.1. Primitive Tokens
+QUOTED_PAIR = r'(?:\\.)'                             # see 3.2.2. Quoted characters
+FWS = r'(?:(?:' + WSP + r'*' + CRLF + r')?' + \
+      WSP + r'+)'                                    # see 3.2.3. Folding white space and comments
+CTEXT = r'[' + NO_WS_CTL + \
+        r'\x21-\x27\x2a-\x5b\x5d-\x7e]'              # see 3.2.3
+CCONTENT = r'(?:' + CTEXT + r'|' + \
+           QUOTED_PAIR + r')'                        # see 3.2.3 (NB: The RFC includes COMMENT here
+# as well, but that would be circular.)
+COMMENT = r'\((?:' + FWS + r'?' + CCONTENT + \
+          r')*' + FWS + r'?\)'                       # see 3.2.3
+CFWS = r'(?:' + FWS + r'?' + COMMENT + ')*(?:' + \
+       FWS + '?' + COMMENT + '|' + FWS + ')'         # see 3.2.3
+ATEXT = r'[\w!#$%&\'\*\+\-/=\?\^`\{\|\}~]'           # see 3.2.4. Atom
+ATOM = CFWS + r'?' + ATEXT + r'+' + CFWS + r'?'      # see 3.2.4
+DOT_ATOM_TEXT = ATEXT + r'+(?:\.' + ATEXT + r'+)*'   # see 3.2.4
+DOT_ATOM = CFWS + r'?' + DOT_ATOM_TEXT + CFWS + r'?' # see 3.2.4
+QTEXT = r'[' + NO_WS_CTL + \
+        r'\x21\x23-\x5b\x5d-\x7e]'                   # see 3.2.5. Quoted strings
+QCONTENT = r'(?:' + QTEXT + r'|' + \
+           QUOTED_PAIR + r')'                        # see 3.2.5
+QUOTED_STRING = CFWS + r'?' + r'"(?:' + FWS + \
+                r'?' + QCONTENT + r')*' + FWS + \
+                r'?' + r'"' + CFWS + r'?'
+LOCAL_PART = r'(?:' + DOT_ATOM + r'|' + \
+             QUOTED_STRING + r')'                    # see 3.4.1. Addr-spec specification
+DTEXT = r'[' + NO_WS_CTL + r'\x21-\x5a\x5e-\x7e]'    # see 3.4.1
+DCONTENT = r'(?:' + DTEXT + r'|' + \
+           QUOTED_PAIR + r')'                        # see 3.4.1
+DOMAIN_LITERAL = CFWS + r'?' + r'\[' + \
+                 r'(?:' + FWS + r'?' + DCONTENT + \
+                 r')*' + FWS + r'?\]' + CFWS + r'?'  # see 3.4.1
+DOMAIN = r'(?:' + DOT_ATOM + r'|' + \
+         DOMAIN_LITERAL + r')'                       # see 3.4.1
+ADDR_SPEC = LOCAL_PART + r'@' + DOMAIN               # see 3.4.1
+
+# A valid address will match exactly the 3.4.1 addr-spec.
+VALID_ADDRESS_REGEXP = '^' + ADDR_SPEC + '$'
+
+MX_DNS_CACHE = {}
+MX_CHECK_CACHE = {}
+
+
+def get_mx_ip(hostname):
+    if hostname not in MX_DNS_CACHE:
+        try:
+            MX_DNS_CACHE[hostname] = DNS.mxlookup(hostname)
+        except ServerError as e:
+            if e.rcode == 3 or e.rcode == 2:  # NXDOMAIN (Non-Existent Domain) or SERVFAIL
+                MX_DNS_CACHE[hostname] = None
+            else:
+                raise
+
+    return MX_DNS_CACHE[hostname]
+
+
+def validate_email(email, check_mx=False, verify=False, debug=False, smtp_timeout=10):
+    """Indicate whether the given string is a valid email address
+    according to the 'addr-spec' portion of RFC 2822 (see section
+    3.4.1).  Parts of the spec that are marked obsolete are *not*
+    included in this test, and certain arcane constructions that
+    depend on circular definitions in the spec may not pass, but in
+    general this should correctly identify any email address likely
+    to be in use as of 2011."""
+    if debug:
+        logger = logging.getLogger('validate_email')
+        logger.setLevel(logging.DEBUG)
+    else:
+        logger = None
+
+    try:
+        assert re.match(VALID_ADDRESS_REGEXP, email) is not None
+        check_mx |= verify
+        if check_mx:
+            if not DNS:
+                raise Exception('For check the mx records or check if the email exists you must '
+                                'have installed pyDNS python package')
+            hostname = email[email.find('@') + 1:]
+            mx_hosts = get_mx_ip(hostname)
+            if mx_hosts is None:
+                return False
+            for mx in mx_hosts:
+                try:
+                    if not verify and mx[1] in MX_CHECK_CACHE:
+                        return MX_CHECK_CACHE[mx[1]]
+                    smtp = smtplib.SMTP(timeout=smtp_timeout)
+                    smtp.connect(mx[1])
+                    MX_CHECK_CACHE[mx[1]] = True
+                    if not verify:
+                        try:
+                            smtp.quit()
+                        except smtplib.SMTPServerDisconnected:
+                            pass
+                        return True
+                    status, _ = smtp.helo()
+                    if status != 250:
+                        smtp.quit()
+                        if debug:
+                            logger.debug(u'%s answer: %s - %s', mx[1], status, _)
+                        continue
+                    smtp.mail('')
+                    status, _ = smtp.rcpt(email)
+                    if status == 250:
+                        smtp.quit()
+                        return True
+                    if debug:
+                        logger.debug(u'%s answer: %s - %s', mx[1], status, _)
+                    smtp.quit()
+                except smtplib.SMTPServerDisconnected:  # Server not permits verify user
+                    if debug:
+                        logger.debug(u'%s disconected.', mx[1])
+                except smtplib.SMTPConnectError:
+                    if debug:
+                        logger.debug(u'Unable to connect to %s.', mx[1])
+            return None
+    except AssertionError:
+        return False
+    except (ServerError, socket.error) as e:
+        if debug:
+            logger.debug('ServerError or socket.error exception raised (%s).', e)
+        return None
+    return True
+
+if __name__ == "__main__":
+    import time
+    while True:
+        email = raw_input('Enter email for validation: ')
+
+        mx = raw_input('Validate MX record? [yN] ')
+        if mx.strip().lower() == 'y':
+            mx = True
+        else:
+            mx = False
+
+        validate = raw_input('Try to contact server for address validation? [yN] ')
+        if validate.strip().lower() == 'y':
+            validate = True
+        else:
+            validate = False
+
+        logging.basicConfig()
+
+        result = validate_email(email, mx, validate, debug=True, smtp_timeout=1)
+        if result:
+            print("Valid!")
+        elif result is None:
+            print("I'm not sure.")
+        else:
+            print("Invalid!")
+
+        time.sleep(1)
+
+
+# import sys
+
+# sys.modules[__name__],sys.modules['validate_email_module'] = validate_email,sys.modules[__name__]
+# from validate_email_module import *