Fix bug where we have not specified any properties

Author: stuartmcalpine

.gitignore

@@ -1,5 +1,5 @@
 # Directories created during CI
-tests/end_to_end_tests/DREGS_data/
+tests/end_to_end_tests/DataRegistry_data/
 tests/end_to_end_tests/dummy_dir/
 
 # Byte-compiled / optimized / DLL files

src/dataregistry/query.py

@@ -157,6 +157,8 @@ def _parse_selected_columns(self, column_names):
         format. If they are in <column_name> format the column name must be
         unique through all tables in the database.
 
+        If column_names is None, return all tables.
+
         Parameters
         ----------
         column_names : list
@@ -167,6 +169,13 @@ def _parse_selected_columns(self, column_names):
         column_list = []
         is_orderable_list = []
 
+        # In the case where column_names is None, we want all tables.
+        if column_names is None:
+            for t in self._table_list:
+                tables_required.add(t)
+
+            return tables_required, column_list, is_orderable_list
+
         # Determine the column name and table it comes from
         for p in column_names:
 

tests/end_to_end_tests/test_query.py

@@ -6,8 +6,15 @@
 datareg = DataRegistry(root_dir="DataRegistry_data")
 
 
+def test_query_all():
+    """Test a query where no properties are chosen, i.e., 'return *"""
+    results = datareg.Query.find_datasets()
+
+    assert results is not None
+
+
 def test_query_dataset_cli():
-    """ Test queries for the dataset table entered from the CLI script """
+    """Test queries for the dataset table entered from the CLI script"""
 
     # Query 1: Make sure we find all datasets entered using the CLI
     f = datareg.Query.gen_filter("dataset.name", "==", "my_cli_dataset")
@@ -18,7 +25,7 @@ def test_query_dataset_cli():
 
 
 def test_query_dataset():
-    """ Test queries for the dataset table """
+    """Test queries for the dataset table"""
 
     # Query 1: Query on dataset name
     f = datareg.Query.gen_filter("dataset.name", "==", "bumped_dataset")
@@ -96,7 +103,7 @@ def test_query_dataset():
 
 
 def test_query_dataset_alias():
-    """ Test queries of dataset alias table """
+    """Test queries of dataset alias table"""
 
     # Query 1: Query on dataset alias
     f = datareg.Query.gen_filter("dataset_alias.alias", "==", "nice_dataset_name")
@@ -111,7 +118,7 @@ def test_query_dataset_alias():
 
 
 def test_query_execution():
-    """ Test queries of execution table """
+    """Test queries of execution table"""
 
     # Query 1: Find the dependencies of an execution
     f = datareg.Query.gen_filter("execution.name", "==", "pipeline_stage_3")