[WIP] Input Validators

recon/utils/validators.py

@@ -0,0 +1,76 @@
+import re
+
+
+# Gingerly lifted from Django 1.3.x:
+# https://github.com/django/django/blob/stable/1.3.x/django/core/validators.py#L45
+# <3 y'all!
+#
+# Restolen from colander
+# https://github.com/Pylons/colander/blob/master/colander/__init__.py
+URL_REGEX = (
+    # {http,ftp}s:// (not required)
+    r"^((?:http|ftp)s?://)?"
+    # Domain
+    r"(?:(?:[A-Z0-9](?:[A-Z0-9-]{0,61}[A-Z0-9])?\.)+"
+    r"(?:[A-Z]{2,6}\.?|[A-Z0-9-]{2,}\.?)|"
+    # Localhost
+    r"localhost|"
+    # IPv6 address
+    r"\[[a-f0-9:]+\]|"
+    # IPv4 address
+    r"\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})"
+    # Optional port
+    r"(?::\d+)?"
+    # Path
+    r"(?:/?|[/?]\S+)$"
+)
+
+
+# Regex for email addresses.
+#
+# Stolen from the WhatWG HTML spec:
+# https://html.spec.whatwg.org/multipage/input.html#e-mail-state-(type=email)
+#
+# If it is good enough for browsers, it is good enough for us!
+#
+# Restolen from colander
+# https://github.com/Pylons/colander/blob/master/colander/__init__.py
+EMAIL_RE = (
+    r"^[a-zA-Z0-9.!#$%&'*+\/=?^_`{|}~-]+@[a-zA-Z0-9]"
+    r"(?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?(?:\.[a-zA-Z0-9]"
+    r"(?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?)*$"
+)
+
+
+class ValidationException(Exception):
+    def __init__(self, input, validator):
+        Exception.__init__(self, f"{input} does not look like a valid {validator}")
+
+
+class Validator(object):
+    """ Regular expression validator
+    """
+
+    def __init__(self, regex, validator=None, flags=0):
+        if isinstance(regex, str):
+            self.match_object = re.compile(regex, flags)
+        else:
+            self.match_object = regex
+        self.validator = validator
+
+    def __call__(self, value):
+        if self.match_object.match(value) is None:
+            raise ValidationException(value, self.validator)
+
+
+class EmailValidator(Validator):
+    """Email address validator
+    """
+
+    def __init__(self):
+        email_regex = EMAIL_RE
+        super(EmailValidator, self).__init__(email_regex, "email")
+
+
+test_email_val = EmailValidator()
+test_email_val("[email protected]")