Merge pull request #1322 from SEL-Columbia/improve_export

Improve export

odk_viewer/models/export.py

@@ -157,23 +157,30 @@ def full_filepath(self):
 
     @classmethod
     def exports_outdated(cls, xform, export_type):
-        # get newest export for xform
+        """Return a boolean:
+           True if there has yet to be an export of this XForm in this type
+             or if the most recent export of this XForm in this type was prior to the latest submission
+           False otherwise
+        """
+
+        result = True # default to re-generating the export
+
         try:
-            latest_export = Export.objects.filter(
-                xform=xform, export_type=export_type,
-                internal_status__in=[Export.SUCCESSFUL, Export.PENDING])\
-                .latest('created_on')
-        except cls.DoesNotExist:
-            return True
-        else:
-            if latest_export.time_of_last_submission is not None \
-                    and xform.time_of_last_submission_update() is not None:
-                return latest_export.time_of_last_submission <\
-                    xform.time_of_last_submission_update()
-            else:
-                # return true if we can't determine the status, to force
-                # auto-generation
-                return True
+            latest_export = Export.objects.filter(models.Q(internal_status=Export.SUCCESSFUL) |
+                                                  models.Q(internal_status=Export.PENDING),
+                                                  xform=xform,
+                                                  export_type=export_type).latest('created_on')
+
+            # there exists an export of this XForm for this data type
+            # but has there been an XForm submission since?
+            # (if either of these are None, it triggers a TypeError, caught below)
+
+            result = ( latest_export.time_of_last_submission < xform.time_of_last_submission_update() )
+
+        except (cls.DoesNotExist, TypeError):
+            pass
+
+        return result
 
     @classmethod
     def is_filename_unique(cls, xform, filename):

utils/export_tools.py

@@ -628,12 +628,16 @@ def query_mongo(username, id_string, query=None, hide_deleted=True):
 
 
 def should_create_new_export(xform, export_type):
-    from odk_viewer.models import Export
-    if Export.objects.filter(xform=xform, export_type=export_type).count() == 0\
-            or Export.exports_outdated(xform, export_type=export_type):
-        return True
-    return False
+    """Determine whether or not a new export file for this
+    xform and data type should be generated.
+
+    This legacy logic is really ugly: the exports_outdated() really
+    should *not* be a classmethod of Export, but doing it incrementally
+    like this for now, until can do a more thorough overhaul later.
+    """
 
+    from odk_viewer.models import Export # ugly!
+    return Export.exports_outdated(xform, export_type=export_type)
 
 def newset_export_for(xform, export_type):
     """