Fix how the dir persistence backend was not listing logbooks

Due to the usage of the os.path.islink check this means that no
logbooks would be returned when get_logbooks was called, which is
not the behavior we want.

Closes-Bug: #1492403

Change-Id: Ife6a5bec777c9e2d820391914ce2c6fbbadf4f79

taskflow/persistence/backends/impl_dir.py

@@ -136,9 +136,13 @@ class Connection(path_based.PathBasedConnection):
             shutil.rmtree(path)
 
     def _get_children(self, path):
+        if path == self.book_path:
+            filter_func = os.path.isdir
+        else:
+            filter_func = os.path.islink
         with _storagefailure_wrapper():
-            return [link for link in os.listdir(path)
+            return [child for child in os.listdir(path)
-                    if os.path.islink(self._join_path(path, link))]
+                    if filter_func(self._join_path(path, child))]
 
     def _ensure_path(self, path):
         with _storagefailure_wrapper():

taskflow/tests/unit/persistence/base.py

@@ -69,6 +69,27 @@ class PersistenceTestMixin(object):
         self.assertIsNotNone(lb2.find(fd.uuid))
         self.assertIsNotNone(lb2.find(fd2.uuid))
 
+    def test_logbook_save_retrieve_many(self):
+        lb_ids = {}
+        for i in range(0, 10):
+            lb_id = uuidutils.generate_uuid()
+            lb_name = 'lb-%s-%s' % (i, lb_id)
+            lb = models.LogBook(name=lb_name, uuid=lb_id)
+            lb_ids[lb_id] = True
+
+            # Should not already exist
+            with contextlib.closing(self._get_connection()) as conn:
+                self.assertRaises(exc.NotFound, conn.get_logbook, lb_id)
+                conn.save_logbook(lb)
+
+        # Now fetch them all
+        with contextlib.closing(self._get_connection()) as conn:
+            lbs = conn.get_logbooks()
+            for lb in lbs:
+                self.assertIn(lb.uuid, lb_ids)
+                lb_ids.pop(lb.uuid)
+            self.assertEqual(0, len(lb_ids))
+
     def test_logbook_save_retrieve(self):
         lb_id = uuidutils.generate_uuid()
         lb_meta = {'1': 2}