diff --git a/airflow/models.py b/airflow/models.py
index 8fa711762b683..b07ab5975ff52 100644
--- a/airflow/models.py
+++ b/airflow/models.py
@@ -149,48 +149,52 @@ def get_dag(self, dag_id):
         """
         Gets the DAG out of the dictionary, and refreshes it if expired
         """
+        # If asking for a known subdag, we want to refresh the parent
         if dag_id in self.dags:
             dag = self.dags[dag_id]
             if dag.is_subdag:
-                orm_dag = DagModel.get_current(dag.parent_dag.dag_id)
-            else:
-                orm_dag = DagModel.get_current(dag_id)
-            if orm_dag and dag.last_loaded < (
-                    orm_dag.last_expired or datetime(2100, 1, 1)):
-                self.process_file(
-                    filepath=orm_dag.fileloc, only_if_updated=False)
-                dag = self.dags[dag_id]
-        else:
-            orm_dag = DagModel.get_current(dag_id)
-            if orm_dag:
-                self.process_file(filepath=orm_dag.fileloc,
-                                  only_if_updated=False)
-            if dag_id in self.dags:
-                dag = self.dags[dag_id]
-            else:
-                dag = None
-        return dag
+                dag_id = dag.parent_dag.dag_id
+
+        # If the dag is absent or expired
+        orm_dag = DagModel.get_current(dag_id)
+        found_dags = []
+        if orm_dag and (
+                dag_id not in self.dags or (
+                    dag.last_loaded < (
+                    orm_dag.last_expired or datetime(2100, 1, 1)
+                )
+        )):
+            # Reprocessing source file
+            found_dags = self.process_file(
+                filepath=orm_dag.fileloc, only_if_updated=False)
+
+        if dag_id in [dag.dag_id for dag in found_dags]:
+            return self.dags[dag_id]
+        elif dag_id in self.dags:
+            del self.dags[dag_id]
 
     def process_file(self, filepath, only_if_updated=True, safe_mode=True):
         """
         Given a path to a python module, this method imports the module and
         look for dag objects within it.
         """
+        found_dags = []
         try:
             # This failed before in what may have been a git sync
             # race condition
             dttm = datetime.fromtimestamp(os.path.getmtime(filepath))
             mod_name, file_ext = os.path.splitext(os.path.split(filepath)[-1])
             mod_name = 'unusual_prefix_' + mod_name
-        except:
-            return
+        except Exception as e:
+            logging.exception(e)
+            return found_dags
 
         if safe_mode and os.path.isfile(filepath):
             # Skip file if no obvious references to airflow or DAG are found.
             with open(filepath, 'r') as f:
                 content = f.read()
                 if not all([s in content for s in ('DAG', 'airflow')]):
-                    return
+                    return found_dags
 
         if (not only_if_updated or
                     filepath not in self.file_last_changed or
@@ -212,8 +216,10 @@ def process_file(self, filepath, only_if_updated=True, safe_mode=True):
                     dag.full_filepath = filepath
                     dag.is_subdag = False
                     self.bag_dag(dag, parent_dag=dag, root_dag=dag)
+                    found_dags.append(dag)
 
             self.file_last_changed[filepath] = dttm
+        return found_dags
 
     @provide_session
     def kill_zombies(self, session):
diff --git a/airflow/www/views.py b/airflow/www/views.py
index ffaaade5da2a5..d22137fdad74a 100644
--- a/airflow/www/views.py
+++ b/airflow/www/views.py
@@ -672,7 +672,8 @@ def pickle_info(self):
         dag_id = request.args.get('dag_id')
         dags = [dagbag.dags.get(dag_id)] if dag_id else dagbag.dags.values()
         for dag in dags:
-            d[dag.dag_id] = dag.pickle_info()
+            if not dag.is_subdag:
+                d[dag.dag_id] = dag.pickle_info()
         return wwwutils.json_response(d)
 
     @expose('/login', methods=['GET', 'POST'])
diff --git a/requirements.txt b/requirements.txt
index 66595e4885ea8..45127ac028f37 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -10,7 +10,7 @@ dill
 filechunkio
 flake8
 flask
-flask-admin==1.2.0
+flask-admin
 flask-cache
 flask-login
 flower