families synchronizing updated to prevend cascade data deletion

synchro_orleans/data/models.py

@@ -93,34 +93,54 @@ class FamilleManager(models.Manager):
             csv_reader = reader(source, delimiter = ';')
             caption = csv_reader.next()
             attrs = map(lambda e: self.attribute_mappings[e], caption)
+            fields = [field.name for field in self.model._meta.fields]
             families = ()
             families_links = ()
+            existing_families = dict((fam.id, fam) for fam in self.all())
+            links = ()
 
             for row in csv_reader:
                 params = dict(zip(attrs, row))
-                obj_id = params['id']
+                obj_id = int(params['id'])
                 pers1 = params.pop('pers1')
                 pers2 = params.pop('pers2')
+                families_links += ((obj_id, pers1, pers2),)
+                changed = False
 
                 # transform all inputs to unicode
                 for key, value in params.iteritems():
                     params[key] = unicode(value, 'utf-8')
 
-                families += (Famille(**params),)
+                if obj_id not in existing_families:
+                    families += (Famille(**params),)
+                else:
+                    obj = existing_families.pop(obj_id)
+                    for field in fields:
+                        if getattr(obj, field) != params[field]:
+                            changed = True
+                            setattr(obj, field, params[field])
+                    if changed:
+                        obj.save()
 
+            if existing_families:
+                self.filter(id__in=existing_families).delete()
+
+            if families:
+                self.bulk_create(families)
+
+            for link in families_links:
+                family, pers1, pers2 = link
                 for person in (pers1, pers2):
                     try:
                         member = Personne.objects.get(pk=person)
-                        famille = self.get(pk=obj_id)
-                        families_links += (LiaisonParentFamille(famille = famille,
-                                                                personne = member),)
-                    except:
+                        famille = self.get(pk=family)
+                        links += (LiaisonParentFamille(famille = famille,
+                                                       personne = member),)
+                    except ValueError:
                         pass
 
-            self.all().delete()
-            self.bulk_create(families)
             LiaisonParentFamille.objects.all().delete()
-            LiaisonParentFamille.objects.bulk_create(families_links)
+            LiaisonParentFamille.objects.bulk_create(links)
 
 class FactureManager(models.Manager):