Fix some types in the FS and VMware drivers

The _get_datadir_path_and_priority and _parse_datastore_info_and_weight methods
may return the priority (or weight) as an integer or a string. This causes a few
issues:

- the caller must cast the result to an integer
- the code is harder to read
- static checkers such as mypy have a hard time processing these methods

We make sure that both methods now return the priority as an integer.

Closes-Bug: #1813092
Change-Id: I9435c88560b01737f9310fe2cba1ca4c84e0f3fa

glance_store/_drivers/filesystem.py

@@ -436,7 +436,7 @@ class Store(glance_store.driver.Store):
                 (datadir_path,
                  priority) = self._get_datadir_path_and_priority(datadir)
                 priority_paths = self.priority_data_map.setdefault(
-                    int(priority), [])
+                    priority, [])
                 self._check_directory_paths(datadir_path, directory_paths,
                                             priority_paths)
                 directory_paths.add(datadir_path)
@@ -490,8 +490,9 @@ class Store(glance_store.driver.Store):
         parts = [part.strip() for part in datadir.rsplit(":", 1)]
         datadir_path = parts[0]
         if len(parts) == 2 and parts[1]:
-            priority = parts[1]
-            if not priority.isdigit():
+            try:
+                priority = int(parts[1])
+            except ValueError:
                 msg = (_("Invalid priority value %(priority)s in "
                          "filesystem configuration") % {'priority': priority})
                 LOG.exception(msg)

glance_store/_drivers/vmware_datastore.py

@@ -463,8 +463,9 @@ class Store(glance_store.Store):
             raise exceptions.BadStoreConfiguration(
                 store_name='vmware_datastore', reason=msg)
         if len(parts) == 3 and parts[2]:
-            weight = parts[2]
-            if not weight.isdigit():
+            try:
+                weight = int(parts[2])
+            except ValueError:
                 msg = (_('Invalid weight value %(weight)s in '
                          'vmware_datastores configuration') %
                        {'weight': weight})
@@ -501,7 +502,7 @@ class Store(glance_store.Store):
                 LOG.error(msg)
                 raise exceptions.BadStoreConfiguration(
                     store_name='vmware_datastore', reason=msg)
-            ds_map.setdefault(int(weight), []).append(ds_obj)
+            ds_map.setdefault(weight, []).append(ds_obj)
         return ds_map
 
     def configure_add(self):

glance_store/tests/unit/test_multistore_vmware.py

@@ -391,7 +391,7 @@ class TestMultiStore(base.MultiStoreBaseTest,
         parts = self.store._parse_datastore_info_and_weight(datastore)
         self.assertEqual('a', parts[0])
         self.assertEqual('b', parts[1])
-        self.assertEqual('100', parts[2])
+        self.assertEqual(100, parts[2])
 
     def test_parse_datastore_info_and_weight_default_weight(self):
         datastore = 'a:b'

glance_store/tests/unit/test_vmware_store.py

@@ -396,7 +396,7 @@ class TestStore(base.StoreBaseTest,
         parts = self.store._parse_datastore_info_and_weight(datastore)
         self.assertEqual('a', parts[0])
         self.assertEqual('b', parts[1])
-        self.assertEqual('100', parts[2])
+        self.assertEqual(100, parts[2])
 
     def test_parse_datastore_info_and_weight_default_weight(self):
         datastore = 'a:b'