text: # Copyright 2012 Nebula, Inc.
  #
  #    Licensed under the Apache License, Version 2.0 (the "License"); you may
  #    not use this file except in compliance with the License. You may obtain
  #    a copy of the License at
  #
  #         http://www.apache.org/licenses/LICENSE-2.0
  #
  #    Unless required by applicable law or agreed to in writing, software
  #    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
  #    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
  #    License for the specific language governing permissions and limitations
  #    under the License.
  
  import re
  
  from django.core.exceptions import ValidationError  # noqa
  from django.core import validators  # noqa
  from django.utils.translation import ugettext_lazy as _
  
  from horizon import conf
  
  
  def validate_port_range(port):
      if port not in range(-1, 65536):
          raise ValidationError(_("Not a valid port number"))
  
  
  def validate_ip_protocol(ip_proto):
      if ip_proto not in range(-1, 256):
          raise ValidationError(_("Not a valid IP protocol number"))
  
  
  def password_validator():
      return conf.HORIZON_CONFIG["password_validator"]["regex"]
  
  
  def password_validator_msg():
      return conf.HORIZON_CONFIG["password_validator"]["help_text"]
  
  
  def validate_port_or_colon_separated_port_range(port_range):
      """Accepts a port number or a single-colon separated range."""
      if port_range.count(':') > 1:
          raise ValidationError(_("One colon allowed in port range"))
      ports = port_range.split(':')
      for port in ports:
          try:
              if int(port) not in range(-1, 65536):
                  raise ValidationError(_("Not a valid port number"))
          except ValueError:
              raise ValidationError(_("Port number must be integer"))
  
  
  def validate_metadata(value):
      error_msg = _('Invalid metadata entry. Use comma-separated'
                    ' key=value pairs')
  
      if value:
          specs = value.split(",")
          for spec in specs:
              keyval = spec.split("=")
              # ensure both sides of "=" exist, but allow blank value
              if not len(keyval) == 2 or not keyval[0]:
                  raise ValidationError(error_msg)
  
  # Same as POSIX [:print:]. Accordingly, diacritics are disallowed.
  PRINT_REGEX = re.compile(r'^[\x20-\x7E]*$')
  
  validate_printable_ascii = validators.RegexValidator(
      PRINT_REGEX,
      _("The string may only contain ASCII printable characters."),
      "invalid_characters")
  