old_contents: from __future__ import unicode_literals
  
  import base32_crockford
  import logging
  
  from django.db.models import F
  from django.http import Http404
  from django.http import HttpResponsePermanentRedirect
  from django.shortcuts import get_object_or_404
  from django.utils.timezone import now
  
  from .models import ShortURL
  from .models import VanityURL
  from .utils import add_query_params
  
  
  logger = logging.getLogger(__name__)
  
  
  def redirect(request, key):
      """
      Given the short URL key, update the statistics and redirect the
      user to the destination URL, including available Google Analytics
      parameters.
      """
      try:
          alias = VanityURL.objects.select_related().get(alias=key.upper())
          key_id = alias.redirect.id
      except VanityURL.DoesNotExist:
          try:
              key_id = base32_crockford.decode(key)
          except ValueError as e:
              logger.warning("Error decoding redirect '%s': %s" % (key, e))
              raise Http404
  
      redirect = get_object_or_404(ShortURL, pk=key_id)
      ShortURL.objects.filter(pk=key_id).update(hits=F('hits') + 1,
                                                last_used=now())
  
      # Inject Google campaign parameters
      utm_params = {'utm_source': redirect.key,
                    'utm_campaign': redirect.campaign,
                    'utm_content': redirect.content,
                    'utm_medium': redirect.medium}
      url = add_query_params(redirect.long_url, utm_params)
  
      return HttpResponsePermanentRedirect(url)
  
new_contents: from __future__ import unicode_literals
  
  import base32_crockford
  import logging
  
  from django.db.models import F
  from django.http import Http404
  from django.http import HttpResponsePermanentRedirect
  from django.shortcuts import get_object_or_404
  from django.utils.timezone import now
  
  from .models import ShortURL
  from .models import VanityURL
  from .utils import add_query_params
  
  
  logger = logging.getLogger(__name__)
  
  
  def redirect(request, key):
      """
      Given the short URL key, update the statistics and redirect the
      user to the destination URL, including available Google Analytics
      parameters.
      """
      try:
          alias = VanityURL.objects.select_related().get(alias=key.upper())
          key_id = alias.redirect.id
      except VanityURL.DoesNotExist:
          try:
              key_id = base32_crockford.decode(key)
          except ValueError as e:
              logger.warning("Error decoding redirect: %s" % e)
              raise Http404
  
      redirect = get_object_or_404(ShortURL, pk=key_id)
      ShortURL.objects.filter(pk=key_id).update(hits=F('hits') + 1,
                                                last_used=now())
  
      # Inject Google campaign parameters
      utm_params = {'utm_source': redirect.key,
                    'utm_campaign': redirect.campaign,
                    'utm_content': redirect.content,
                    'utm_medium': redirect.medium}
      url = add_query_params(redirect.long_url, utm_params)
  
      return HttpResponsePermanentRedirect(url)
  
subject: Simplify invalid decode warning text