Ticket #5741: get_default.diff

django/db/models/query.py

@@ -254 +254 @@
 
     def get(self, *args, **kwargs):
         "Performs the SELECT and returns a single object matching the given keyword arguments."
+        has_default = False
+        if 'default' in kwargs:
+            default_value = kwargs.pop('default')
+            has_default = True
         clone = self.filter(*args, **kwargs)
         # clean up SQL by removing unneeded ORDER BY
         if not clone._order_by:
             clone._order_by = ()
         obj_list = list(clone)
         if len(obj_list) < 1:
+            if has_default:
+                return default_value
             raise self.model.DoesNotExist, "%s matching query does not exist." % self.model._meta.object_name
         assert len(obj_list) == 1, "get() returned more than one %s -- it returned %s! Lookup parameters were %s" % (self.model._meta.object_name, len(obj_list), kwargs)
         return obj_list[0]

docs/db-api.txt

@@ -839 +839 @@
     except ObjectDoesNotExist:
         print "Either the entry or blog doesn't exist."
 
+**New in Django development version**
+
+``get()`` may take a kwarg named ``default``, similar to the ``get()`` method
+on dicts. When ``default`` is specified, and no object is found, the value of
+``default`` is returned. If ``default`` is not specified, the ``DoesNotExist``
+exception is raised as usual.
+
+For existing models with a field named ``default``, the more verbose
+``default__exact`` lookup syntax must be used.
+
 ``create(**kwargs)``
 ~~~~~~~~~~~~~~~~~~~~