Initialise the node manager correctly

populate_startup_nodes is meant to put all the known nodes in the startup nodes list,
but when it was called, the nodes list it was using (self.nodes) is not populated yet.
So populate startup nodes after initialising self.nodes,
otherwise when we choose a random connection (which is chosen from startup nodes),
the options are too limited. Often a user will specify a single startup node at the beginning.

Author: JonathanWylie

rediscluster/nodemanager.py

@@ -306,6 +306,7 @@ def initialize(self):
         # Set the tmp variables to the real variables
         self.slots = tmp_slots
         self.nodes = nodes_cache
+        self.populate_startup_nodes()
         self.reinitialize_counter = 0
 
         log.debug("NodeManager initialize done : Nodes")
@@ -413,7 +414,8 @@ def set_node(self, host, port, server_type=None):
 
     def populate_startup_nodes(self):
         """
-        Do something with all startup nodes and filters out any duplicates
+        Use nodes to populate startup_nodes, so that we have more chances
+        if a subset of the cluster fails.
         """
         for item in self.startup_nodes:
             self.set_node_name(item)

tests/test_cluster_node_manager.py

@@ -169,7 +169,7 @@ def test_empty_startup_nodes():
 
 def test_wrong_startup_nodes_type():
     """
-    If something other then a list type itteratable is provided it should fail
+    If something other then a list type iterable is provided it should fail
     """
     with pytest.raises(RedisClusterException):
         NodeManager({})
@@ -263,9 +263,19 @@ def test_all_nodes():
         assert node in nodes
 
 
+def test_startup_nodes_are_populated():
+    """
+    Set a list of nodes and it should be possible to iterate over all
+    """
+    n = NodeManager(startup_nodes=[{"host": "127.0.0.1", "port": 7000}])
+    n.initialize()
+
+    assert sorted([node['port'] for node in n.startup_nodes]) == [7000, 7000, 7001, 7002, 7003, 7004, 7005]
+
+
 def test_all_nodes_masters():
     """
-    Set a list of nodes with random masters/slaves config and it shold be possible
+    Set a list of nodes with random masters/slaves config and it should be possible
     to iterate over all of them.
     """
     n = NodeManager(

tests/test_multiprocessing_cluster.py

@@ -117,7 +117,6 @@ def target(pool):
 
         # Check that connection is still alive after fork process has exited
         # and disconnected the connections in its pool
-        conn = pool.get_random_connection()
         with exit_callback(pool.release, conn):
             assert conn.send_command('ping') is None
             assert conn.read_response() == b'PONG'