Improve cached_label managemnent

* more genericity
* adapt it to archaeological files

4 files changed, 300 insertions, 9 deletions

diff --git a/archaeological_files/migrations/0007_auto__add_field_file_cached_label__add_field_historicalfile_cached_lab.py b/archaeological_files/migrations/0007_auto__add_field_file_cached_label__add_field_historicalfile_cached_lab.py
new file mode 100644
index 000000000..92e979bd4
--- /dev/null
+++ b/archaeological_files/migrations/0007_auto__add_field_file_cached_label__add_field_historicalfile_cached_lab.py
@@ -0,0 +1,251 @@
+# -*- coding: utf-8 -*-
+import datetime
+from south.db import db
+from south.v2 import SchemaMigration
+from django.db import models
+
+
+class Migration(SchemaMigration):
+
+    def forwards(self, orm):
+        # Adding field 'File.cached_label'
+        db.add_column('archaeological_files_file', 'cached_label',
+                      self.gf('django.db.models.fields.CharField')(max_length=100, null=True, blank=True),
+                      keep_default=False)
+
+        # Adding field 'HistoricalFile.cached_label'
+        db.add_column('archaeological_files_historicalfile', 'cached_label',
+                      self.gf('django.db.models.fields.CharField')(max_length=100, null=True, blank=True),
+                      keep_default=False)
+
+
+    def backwards(self, orm):
+        # Deleting field 'File.cached_label'
+        db.delete_column('archaeological_files_file', 'cached_label')
+
+        # Deleting field 'HistoricalFile.cached_label'
+        db.delete_column('archaeological_files_historicalfile', 'cached_label')
+
+
+    models = {
+        'archaeological_files.file': {
+            'Meta': {'ordering': "['-year', '-numeric_reference']", 'object_name': 'File'},
+            'address': ('django.db.models.fields.TextField', [], {'null': 'True', 'blank': 'True'}),
+            'address_complement': ('django.db.models.fields.TextField', [], {'null': 'True', 'blank': 'True'}),
+            'cached_label': ('django.db.models.fields.CharField', [], {'max_length': '100', 'null': 'True', 'blank': 'True'}),
+            'comment': ('django.db.models.fields.TextField', [], {'null': 'True', 'blank': 'True'}),
+            'creation_date': ('django.db.models.fields.DateField', [], {'default': 'datetime.date.today'}),
+            'end_date': ('django.db.models.fields.DateField', [], {'null': 'True', 'blank': 'True'}),
+            'file_type': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['archaeological_files.FileType']"}),
+            'general_contractor': ('django.db.models.fields.related.ForeignKey', [], {'blank': 'True', 'related_name': "'+'", 'null': 'True', 'to': "orm['ishtar_common.Person']"}),
+            'history_modifier': ('django.db.models.fields.related.ForeignKey', [], {'related_name': "'+'", 'to': "orm['auth.User']"}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'in_charge': ('django.db.models.fields.related.ForeignKey', [], {'blank': 'True', 'related_name': "'+'", 'null': 'True', 'to': "orm['ishtar_common.Person']"}),
+            'internal_reference': ('django.db.models.fields.CharField', [], {'max_length': '60', 'unique': 'True', 'null': 'True', 'blank': 'True'}),
+            'name': ('django.db.models.fields.CharField', [], {'max_length': '100', 'null': 'True', 'blank': 'True'}),
+            'numeric_reference': ('django.db.models.fields.IntegerField', [], {'null': 'True', 'blank': 'True'}),
+            'permit_reference': ('django.db.models.fields.CharField', [], {'max_length': '60', 'null': 'True', 'blank': 'True'}),
+            'permit_type': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['archaeological_files.PermitType']", 'null': 'True', 'blank': 'True'}),
+            'postal_code': ('django.db.models.fields.CharField', [], {'max_length': '10', 'null': 'True', 'blank': 'True'}),
+            'reception_date': ('django.db.models.fields.DateField', [], {'null': 'True', 'blank': 'True'}),
+            'reference_number': ('django.db.models.fields.IntegerField', [], {'null': 'True', 'blank': 'True'}),
+            'related_file': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['archaeological_files.File']", 'null': 'True', 'blank': 'True'}),
+            'saisine_type': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['archaeological_files.SaisineType']", 'null': 'True', 'blank': 'True'}),
+            'total_developed_surface': ('django.db.models.fields.IntegerField', [], {'null': 'True', 'blank': 'True'}),
+            'total_surface': ('django.db.models.fields.IntegerField', [], {'null': 'True', 'blank': 'True'}),
+            'town_planning_service': ('django.db.models.fields.related.ForeignKey', [], {'blank': 'True', 'related_name': "'+'", 'null': 'True', 'to': "orm['ishtar_common.Organization']"}),
+            'towns': ('django.db.models.fields.related.ManyToManyField', [], {'related_name': "'file'", 'symmetrical': 'False', 'to': "orm['ishtar_common.Town']"}),
+            'year': ('django.db.models.fields.IntegerField', [], {'default': '2013'})
+        },
+        'archaeological_files.filebydepartment': {
+            'Meta': {'object_name': 'FileByDepartment', 'db_table': "'file_department'", 'managed': 'False'},
+            'department': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['ishtar_common.Department']", 'null': 'True', 'blank': 'True'}),
+            'file': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['archaeological_files.File']"}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'})
+        },
+        'archaeological_files.filetype': {
+            'Meta': {'object_name': 'FileType'},
+            'available': ('django.db.models.fields.BooleanField', [], {'default': 'False'}),
+            'comment': ('django.db.models.fields.TextField', [], {'null': 'True', 'blank': 'True'}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'label': ('django.db.models.fields.CharField', [], {'max_length': '100'}),
+            'txt_idx': ('django.db.models.fields.CharField', [], {'unique': 'True', 'max_length': '30'})
+        },
+        'archaeological_files.historicalfile': {
+            'Meta': {'ordering': "('-history_date', '-history_id')", 'object_name': 'HistoricalFile'},
+            'address': ('django.db.models.fields.TextField', [], {'null': 'True', 'blank': 'True'}),
+            'address_complement': ('django.db.models.fields.TextField', [], {'null': 'True', 'blank': 'True'}),
+            'cached_label': ('django.db.models.fields.CharField', [], {'max_length': '100', 'null': 'True', 'blank': 'True'}),
+            'comment': ('django.db.models.fields.TextField', [], {'null': 'True', 'blank': 'True'}),
+            'creation_date': ('django.db.models.fields.DateField', [], {'default': 'datetime.date.today'}),
+            'end_date': ('django.db.models.fields.DateField', [], {'null': 'True', 'blank': 'True'}),
+            'file_type_id': ('django.db.models.fields.IntegerField', [], {'db_index': 'True', 'null': 'True', 'blank': 'True'}),
+            'general_contractor_id': ('django.db.models.fields.IntegerField', [], {'db_index': 'True', 'null': 'True', 'blank': 'True'}),
+            'history_date': ('django.db.models.fields.DateTimeField', [], {'auto_now_add': 'True', 'blank': 'True'}),
+            'history_id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'history_modifier_id': ('django.db.models.fields.IntegerField', [], {'db_index': 'True', 'null': 'True', 'blank': 'True'}),
+            'history_type': ('django.db.models.fields.CharField', [], {'max_length': '1'}),
+            'history_user': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['auth.User']", 'null': 'True'}),
+            'id': ('django.db.models.fields.IntegerField', [], {'db_index': 'True', 'blank': 'True'}),
+            'in_charge_id': ('django.db.models.fields.IntegerField', [], {'db_index': 'True', 'null': 'True', 'blank': 'True'}),
+            'internal_reference': ('django.db.models.fields.CharField', [], {'db_index': 'True', 'max_length': '60', 'null': 'True', 'blank': 'True'}),
+            'name': ('django.db.models.fields.CharField', [], {'max_length': '100', 'null': 'True', 'blank': 'True'}),
+            'numeric_reference': ('django.db.models.fields.IntegerField', [], {'null': 'True', 'blank': 'True'}),
+            'permit_reference': ('django.db.models.fields.CharField', [], {'max_length': '60', 'null': 'True', 'blank': 'True'}),
+            'permit_type_id': ('django.db.models.fields.IntegerField', [], {'db_index': 'True', 'null': 'True', 'blank': 'True'}),
+            'postal_code': ('django.db.models.fields.CharField', [], {'max_length': '10', 'null': 'True', 'blank': 'True'}),
+            'reception_date': ('django.db.models.fields.DateField', [], {'null': 'True', 'blank': 'True'}),
+            'reference_number': ('django.db.models.fields.IntegerField', [], {'null': 'True', 'blank': 'True'}),
+            'related_file_id': ('django.db.models.fields.IntegerField', [], {'db_index': 'True', 'null': 'True', 'blank': 'True'}),
+            'saisine_type_id': ('django.db.models.fields.IntegerField', [], {'db_index': 'True', 'null': 'True', 'blank': 'True'}),
+            'total_developed_surface': ('django.db.models.fields.IntegerField', [], {'null': 'True', 'blank': 'True'}),
+            'total_surface': ('django.db.models.fields.IntegerField', [], {'null': 'True', 'blank': 'True'}),
+            'town_planning_service_id': ('django.db.models.fields.IntegerField', [], {'db_index': 'True', 'null': 'True', 'blank': 'True'}),
+            'year': ('django.db.models.fields.IntegerField', [], {'default': '2013'})
+        },
+        'archaeological_files.permittype': {
+            'Meta': {'object_name': 'PermitType'},
+            'available': ('django.db.models.fields.BooleanField', [], {'default': 'False'}),
+            'comment': ('django.db.models.fields.TextField', [], {'null': 'True', 'blank': 'True'}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'label': ('django.db.models.fields.CharField', [], {'max_length': '100'}),
+            'txt_idx': ('django.db.models.fields.CharField', [], {'unique': 'True', 'max_length': '30'})
+        },
+        'archaeological_files.saisinetype': {
+            'Meta': {'object_name': 'SaisineType'},
+            'available': ('django.db.models.fields.BooleanField', [], {'default': 'False'}),
+            'comment': ('django.db.models.fields.TextField', [], {'null': 'True', 'blank': 'True'}),
+            'delay': ('django.db.models.fields.IntegerField', [], {}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'label': ('django.db.models.fields.CharField', [], {'max_length': '100'}),
+            'txt_idx': ('django.db.models.fields.CharField', [], {'unique': 'True', 'max_length': '30'})
+        },
+        'auth.group': {
+            'Meta': {'object_name': 'Group'},
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'name': ('django.db.models.fields.CharField', [], {'unique': 'True', 'max_length': '80'}),
+            'permissions': ('django.db.models.fields.related.ManyToManyField', [], {'to': "orm['auth.Permission']", 'symmetrical': 'False', 'blank': 'True'})
+        },
+        'auth.permission': {
+            'Meta': {'ordering': "('content_type__app_label', 'content_type__model', 'codename')", 'unique_together': "(('content_type', 'codename'),)", 'object_name': 'Permission'},
+            'codename': ('django.db.models.fields.CharField', [], {'max_length': '100'}),
+            'content_type': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['contenttypes.ContentType']"}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'name': ('django.db.models.fields.CharField', [], {'max_length': '50'})
+        },
+        'auth.user': {
+            'Meta': {'object_name': 'User'},
+            'date_joined': ('django.db.models.fields.DateTimeField', [], {'default': 'datetime.datetime.now'}),
+            'email': ('django.db.models.fields.EmailField', [], {'max_length': '75', 'blank': 'True'}),
+            'first_name': ('django.db.models.fields.CharField', [], {'max_length': '30', 'blank': 'True'}),
+            'groups': ('django.db.models.fields.related.ManyToManyField', [], {'to': "orm['auth.Group']", 'symmetrical': 'False', 'blank': 'True'}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'is_active': ('django.db.models.fields.BooleanField', [], {'default': 'True'}),
+            'is_staff': ('django.db.models.fields.BooleanField', [], {'default': 'False'}),
+            'is_superuser': ('django.db.models.fields.BooleanField', [], {'default': 'False'}),
+            'last_login': ('django.db.models.fields.DateTimeField', [], {'default': 'datetime.datetime.now'}),
+            'last_name': ('django.db.models.fields.CharField', [], {'max_length': '30', 'blank': 'True'}),
+            'password': ('django.db.models.fields.CharField', [], {'max_length': '128'}),
+            'user_permissions': ('django.db.models.fields.related.ManyToManyField', [], {'to': "orm['auth.Permission']", 'symmetrical': 'False', 'blank': 'True'}),
+            'username': ('django.db.models.fields.CharField', [], {'unique': 'True', 'max_length': '30'})
+        },
+        'contenttypes.contenttype': {
+            'Meta': {'ordering': "('name',)", 'unique_together': "(('app_label', 'model'),)", 'object_name': 'ContentType', 'db_table': "'django_content_type'"},
+            'app_label': ('django.db.models.fields.CharField', [], {'max_length': '100'}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'model': ('django.db.models.fields.CharField', [], {'max_length': '100'}),
+            'name': ('django.db.models.fields.CharField', [], {'max_length': '100'})
+        },
+        'ishtar_common.arrondissement': {
+            'Meta': {'object_name': 'Arrondissement'},
+            'department': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['ishtar_common.Department']"}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'name': ('django.db.models.fields.CharField', [], {'max_length': '30'})
+        },
+        'ishtar_common.canton': {
+            'Meta': {'object_name': 'Canton'},
+            'arrondissement': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['ishtar_common.Arrondissement']"}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'name': ('django.db.models.fields.CharField', [], {'max_length': '30'})
+        },
+        'ishtar_common.department': {
+            'Meta': {'ordering': "['number']", 'object_name': 'Department'},
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'label': ('django.db.models.fields.CharField', [], {'max_length': '30'}),
+            'number': ('django.db.models.fields.CharField', [], {'unique': 'True', 'max_length': '3'})
+        },
+        'ishtar_common.organization': {
+            'Meta': {'object_name': 'Organization'},
+            'address': ('django.db.models.fields.TextField', [], {'null': 'True', 'blank': 'True'}),
+            'address_complement': ('django.db.models.fields.TextField', [], {'null': 'True', 'blank': 'True'}),
+            'country': ('django.db.models.fields.CharField', [], {'max_length': '30', 'null': 'True', 'blank': 'True'}),
+            'history_modifier': ('django.db.models.fields.related.ForeignKey', [], {'related_name': "'+'", 'to': "orm['auth.User']"}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'mobile_phone': ('django.db.models.fields.CharField', [], {'max_length': '18', 'null': 'True', 'blank': 'True'}),
+            'name': ('django.db.models.fields.CharField', [], {'max_length': '100'}),
+            'organization_type': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['ishtar_common.OrganizationType']"}),
+            'phone': ('django.db.models.fields.CharField', [], {'max_length': '18', 'null': 'True', 'blank': 'True'}),
+            'postal_code': ('django.db.models.fields.CharField', [], {'max_length': '10', 'null': 'True', 'blank': 'True'}),
+            'town': ('django.db.models.fields.CharField', [], {'max_length': '30', 'null': 'True', 'blank': 'True'})
+        },
+        'ishtar_common.organizationtype': {
+            'Meta': {'object_name': 'OrganizationType'},
+            'available': ('django.db.models.fields.BooleanField', [], {'default': 'False'}),
+            'comment': ('django.db.models.fields.TextField', [], {'null': 'True', 'blank': 'True'}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'label': ('django.db.models.fields.CharField', [], {'max_length': '100'}),
+            'txt_idx': ('django.db.models.fields.CharField', [], {'unique': 'True', 'max_length': '30'})
+        },
+        'ishtar_common.person': {
+            'Meta': {'object_name': 'Person'},
+            'address': ('django.db.models.fields.TextField', [], {'null': 'True', 'blank': 'True'}),
+            'address_complement': ('django.db.models.fields.TextField', [], {'null': 'True', 'blank': 'True'}),
+            'attached_to': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['ishtar_common.Organization']", 'null': 'True', 'blank': 'True'}),
+            'country': ('django.db.models.fields.CharField', [], {'max_length': '30', 'null': 'True', 'blank': 'True'}),
+            'email': ('django.db.models.fields.CharField', [], {'max_length': '40', 'null': 'True', 'blank': 'True'}),
+            'history_modifier': ('django.db.models.fields.related.ForeignKey', [], {'related_name': "'+'", 'to': "orm['auth.User']"}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'mobile_phone': ('django.db.models.fields.CharField', [], {'max_length': '18', 'null': 'True', 'blank': 'True'}),
+            'name': ('django.db.models.fields.CharField', [], {'max_length': '30'}),
+            'person_type': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['ishtar_common.PersonType']"}),
+            'phone': ('django.db.models.fields.CharField', [], {'max_length': '18', 'null': 'True', 'blank': 'True'}),
+            'postal_code': ('django.db.models.fields.CharField', [], {'max_length': '10', 'null': 'True', 'blank': 'True'}),
+            'surname': ('django.db.models.fields.CharField', [], {'max_length': '20', 'null': 'True', 'blank': 'True'}),
+            'title': ('django.db.models.fields.CharField', [], {'max_length': '2'}),
+            'town': ('django.db.models.fields.CharField', [], {'max_length': '30', 'null': 'True', 'blank': 'True'})
+        },
+        'ishtar_common.persontype': {
+            'Meta': {'object_name': 'PersonType'},
+            'available': ('django.db.models.fields.BooleanField', [], {'default': 'False'}),
+            'comment': ('django.db.models.fields.TextField', [], {'null': 'True', 'blank': 'True'}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'label': ('django.db.models.fields.CharField', [], {'max_length': '100'}),
+            'rights': ('django.db.models.fields.related.ManyToManyField', [], {'to': "orm['ishtar_common.WizardStep']", 'symmetrical': 'False'}),
+            'txt_idx': ('django.db.models.fields.CharField', [], {'unique': 'True', 'max_length': '30'})
+        },
+        'ishtar_common.town': {
+            'Meta': {'ordering': "['numero_insee']", 'object_name': 'Town'},
+            'canton': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['ishtar_common.Canton']", 'null': 'True', 'blank': 'True'}),
+            'center': ('django.contrib.gis.db.models.fields.PointField', [], {'srid': '27572', 'null': 'True', 'blank': 'True'}),
+            'departement': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['ishtar_common.Department']", 'null': 'True', 'blank': 'True'}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'name': ('django.db.models.fields.CharField', [], {'max_length': '100'}),
+            'numero_insee': ('django.db.models.fields.CharField', [], {'unique': 'True', 'max_length': '6'}),
+            'surface': ('django.db.models.fields.IntegerField', [], {'null': 'True', 'blank': 'True'})
+        },
+        'ishtar_common.wizard': {
+            'Meta': {'ordering': "['url_name']", 'object_name': 'Wizard'},
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'url_name': ('django.db.models.fields.CharField', [], {'unique': 'True', 'max_length': '128'})
+        },
+        'ishtar_common.wizardstep': {
+            'Meta': {'ordering': "['wizard', 'order']", 'object_name': 'WizardStep'},
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'name': ('django.db.models.fields.CharField', [], {'max_length': '128'}),
+            'order': ('django.db.models.fields.IntegerField', [], {}),
+            'url_name': ('django.db.models.fields.CharField', [], {'max_length': '128'}),
+            'wizard': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['ishtar_common.Wizard']"})
+        }
+    }
+
+    complete_apps = ['archaeological_files']
\ No newline at end of file
diff --git a/archaeological_files/models.py b/archaeological_files/models.py
index 8f2f513d2..ae6ad726e 100644
--- a/archaeological_files/models.py
+++ b/archaeological_files/models.py
@@ -22,8 +22,11 @@ import datetime
 from django.conf import settings
 from django.contrib.gis.db import models
 from django.db.models import Q, Count, Sum
+from django.db.models.signals import post_save, m2m_changed
 from django.utils.translation import ugettext_lazy as _, ugettext
 
+from ishtar_common.utils import cached_label_changed
+
 from ishtar_common.models import GeneralType, BaseHistorizedItem, \
     HistoricalRecords, OwnPerms, Person, Organization, Department, Town, \
     Dashboard, IshtarUser
@@ -100,6 +103,8 @@ class File(BaseHistorizedItem, OwnPerms):
     postal_code = models.CharField(_(u"Main address - postal code"),
                                    max_length=10, null=True, blank=True)
     comment = models.TextField(_(u"Comment"), null=True, blank=True)
+    cached_label = models.CharField(_(u"Cached name"), max_length=100,
+                                   null=True, blank=True)
     history = HistoricalRecords()
 
     class Meta:
@@ -128,6 +133,12 @@ class File(BaseHistorizedItem, OwnPerms):
         return cls.objects.count()
 
     def __unicode__(self):
+        if self.cached_label:
+            return self.cached_label
+        self.save()
+        return self.cached_label
+
+    def _generate_cached_label(self):
         items = [unicode(_('Intercommunal'))]
         if self.towns.count() == 1:
             items[0] = unicode(self.towns.all()[0])
@@ -175,6 +186,9 @@ class File(BaseHistorizedItem, OwnPerms):
     def is_preventive(self):
         return FileType.is_preventive(self.file_type.pk)
 
+m2m_changed.connect(cached_label_changed, sender=File.towns.through)
+post_save.connect(cached_label_changed, sender=File)
+
 class FileByDepartment(models.Model):
     '''
     Database view for dashboard
diff --git a/archaeological_operations/models.py b/archaeological_operations/models.py
index e985400be..7c57087c5 100644
--- a/archaeological_operations/models.py
+++ b/archaeological_operations/models.py
@@ -26,6 +26,8 @@ from django.db.models import Q, Count, Sum, Max, Avg
 from django.db.models.signals import post_save, m2m_changed
 from django.utils.translation import ugettext_lazy as _, ugettext
 
+from ishtar_common.utils import cached_label_changed
+
 from ishtar_common.models import GeneralType, BaseHistorizedItem, \
      HistoricalRecords, LightHistorizedItem, OwnPerms, Department, Source,\
      Person, Organization, Town, Dashboard, IshtarUser
@@ -143,7 +145,8 @@ class Operation(BaseHistorizedItem, OwnPerms):
     def __unicode__(self):
         if self.cached_label:
             return self.cached_label
-        return self._generate_cached_label()
+        self.save()
+        return self.cached_label
 
     def _generate_cached_label(self):
         items = [unicode(_('Intercommunal'))]
@@ -152,9 +155,8 @@ class Operation(BaseHistorizedItem, OwnPerms):
         if self.operation_code:
             items.append("-".join((unicode(self.year),
                                unicode(self.operation_code))))
-        self.cached_label = settings.JOINT.join(items)
-        self.save()
-        return self.cached_label
+        cached_label = settings.JOINT.join(items)
+        return cached_label
 
     def grouped_parcels(self):
         return Parcel.grouped_parcels(list(self.parcels.all()))
@@ -235,11 +237,7 @@ class Operation(BaseHistorizedItem, OwnPerms):
         return {'date':item.history_date,
                 'user':IshtarUser.objects.get(pk=item.history_modifier_id)}
 
-def associated_towns_changed(sender, **kwargs):
-    if not kwargs.get('instance'):
-        return
-    kwargs.get('instance')._generate_cached_label()
-m2m_changed.connect(associated_towns_changed, sender=Operation.towns.through)
+m2m_changed.connect(cached_label_changed, sender=Operation.towns.through)
 
 def operation_post_save(sender, **kwargs):
     if not kwargs['instance']:
@@ -254,6 +252,7 @@ def operation_post_save(sender, **kwargs):
         fnap_percent = float(operation.fnap_cost)*100/operation.cost
         operation.fnap_financing = fnap_percent
         operation.save()
+    cached_label_changed(sender, **kwargs)
 post_save.connect(operation_post_save, sender=Operation)
 
 class OperationByDepartment(models.Model):
diff --git a/ishtar_common/utils.py b/ishtar_common/utils.py
new file mode 100644
index 000000000..50f4a6b41
--- /dev/null
+++ b/ishtar_common/utils.py
@@ -0,0 +1,27 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+# Copyright (C) 2013 Étienne Loks  <etienne.loks_AT_peacefrogsDOTnet>
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as
+# published by the Free Software Foundation, either version 3 of the
+# License, or (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+# See the file COPYING for details.
+
+def cached_label_changed(sender, **kwargs):
+    if not kwargs.get('instance'):
+        return
+    instance = kwargs.get('instance')
+    lbl = instance._generate_cached_label()
+    if lbl != instance.cached_label:
+        instance.cached_label = lbl
+        instance.save()