Get persistence backend via kwargs instead of conf

The persistence backend that the zookeeper backend uses to
load logbooks when they appear should come in via a kwarg
instead of coming in via conf (since it's not configuration).

Change-Id: I300d7681e5884a989549c8b84d29f04e9ea3d060

taskflow/jobs/backends/impl_zookeeper.py

@@ -143,7 +143,7 @@ class ZookeeperJob(base_job.Job):
 
 
 class ZookeeperJobBoard(jobboard.JobBoard):
-    def __init__(self, name, conf, client=None):
+    def __init__(self, name, conf, client=None, persistence=None):
         super(ZookeeperJobBoard, self).__init__(name, conf)
         if client is not None:
             self._client = client
@@ -162,7 +162,7 @@ class ZookeeperJobBoard(jobboard.JobBoard):
         # not currently the full logbook (later when a zookeeper backend
         # appears we can likely optimize for that backend usage by directly
         # reading from the path where the data is stored, if we want).
-        self._persistence = self._conf.get("persistence")
+        self._persistence = persistence
         # Misc. internal details
         self._known_jobs = {}
         self._job_mutate = self._client.handler.rlock_object()

taskflow/tests/unit/jobs/test_zk_job.py

@@ -44,11 +44,12 @@ def connect_close(*args):
             a.close()
 
 
-def create_board(**kwargs):
-    client = fake_client.FakeClient()
-    board = impl_zookeeper.ZookeeperJobBoard('test-board',
-                                             conf=dict(kwargs),
-                                             client=client)
+def create_board(client=None, persistence=None):
+    if not client:
+        client = fake_client.FakeClient()
+    board = impl_zookeeper.ZookeeperJobBoard('test-board', {},
+                                             client=client,
+                                             persistence=persistence)
     return (client, board)