Source Code for Module django.contrib.admin.filterspecs

  1  """ 
  2  FilterSpec encapsulates the logic for displaying filters in the Django admin. 
  3  Filters are specified in models with the "list_filter" option. 
  4   
  5  Each filter subclass knows how to display a filter for a field that passes a 
  6  certain test -- e.g. being a DateField or ForeignKey. 
  7  """ 
  8   
  9  from django.db import models 
 10  from django.utils.encoding import smart_unicode, iri_to_uri 
 11  from django.utils.translation import ugettext as _ 
 12  from django.utils.html import escape 
 13  from django.utils.safestring import mark_safe 
 14  import datetime 
 15   
 16 -class FilterSpec(object): 
 17      filter_specs = [] 
 18 -    def __init__(self, f, request, params, model): 
 19          self.field = f 
 20          self.params = params 
 21   
 22 -    def register(cls, test, factory): 
 23          cls.filter_specs.append((test, factory)) 
 24      register = classmethod(register) 
 25   
 26 -    def create(cls, f, request, params, model): 
 27          for test, factory in cls.filter_specs: 
 28              if test(f): 
 29                  return factory(f, request, params, model) 
 30      create = classmethod(create) 
 31   
 32 -    def has_output(self): 
 33          return True 
 34   
 35 -    def choices(self, cl): 
 36          raise NotImplementedError() 
 37   
 38 -    def title(self): 
 39          return self.field.verbose_name 
 40   
 41 -    def output(self, cl): 
 42          t = [] 
 43          if self.has_output(): 
 44              t.append(_(u'<h3>By %s:</h3>\n<ul>\n') % escape(self.title())) 
 45   
 46              for choice in self.choices(cl): 
 47                  t.append(u'<li%s><a href="%s">%s</a></li>\n' % \ 
 48                      ((choice['selected'] and ' class="selected"' or ''), 
 49                       iri_to_uri(choice['query_string']), 
 50                       choice['display'])) 
 51              t.append('</ul>\n\n') 
 52          return mark_safe("".join(t)) 
 53   
 54 -class RelatedFilterSpec(FilterSpec): 
 55 -    def __init__(self, f, request, params, model): 
 56          super(RelatedFilterSpec, self).__init__(f, request, params, model) 
 57          if isinstance(f, models.ManyToManyField): 
 58              self.lookup_title = f.rel.to._meta.verbose_name 
 59          else: 
 60              self.lookup_title = f.verbose_name 
 61          self.lookup_kwarg = '%s__%s__exact' % (f.name, f.rel.to._meta.pk.name) 
 62          self.lookup_val = request.GET.get(self.lookup_kwarg, None) 
 63          self.lookup_choices = f.rel.to._default_manager.all() 
 64   
 65 -    def has_output(self): 
 66          return len(self.lookup_choices) > 1 
 67   
 68 -    def title(self): 
 69          return self.lookup_title 
 70   
 71 -    def choices(self, cl): 
 72          yield {'selected': self.lookup_val is None, 
 73                 'query_string': cl.get_query_string({}, [self