Toggle host-key-checking for openstack provider.labels

This adds the ability for a pool.label to override the
pool.host-key-checking value, while having a label exist in the same
pool.  This is helpful because it is possible for 1 pool to mix network
configuration, and some nodes maybe missing a default gateway (making
them unroutable by default).

Change-Id: I934d42b8e48aedb0ebc03137b7305eb2af390fc7
Signed-off-by: Paul Belanger <pabelanger@redhat.com>

doc/source/configuration.rst

@@ -926,6 +926,18 @@ Selecting the OpenStack driver adds the following options to the
             If given, the label for use in this pool will create a
             volume from the image and boot the node from it.
 
+        .. attr:: host-key-checking
+           :type: bool
+           :default: True
+
+           Specify custom behavior of validation of SSH host keys.  When set to
+           False, nodepool-launcher will not ssh-keyscan nodes after they are
+           booted. This might be needed if nodepool-launcher and the nodes it
+           launches are on different networks.  The default value is True.
+
+           .. note:: This value will override the value for
+                     :attr:`providers.[openstack].pools.host-key-checking`.
+
         .. attr:: networks
            :type: list
 

nodepool/driver/openstack/config.py

@@ -91,6 +91,7 @@ class ProviderLabel(ConfigValue):
         self.instance_properties = None
         self.userdata = None
         self.networks = []
+        self.host_key_checking = True
         # The ProviderPool object that owns this label.
         self.pool = None
 
@@ -109,7 +110,8 @@ class ProviderLabel(ConfigValue):
                     other.volume_size == self.volume_size and
                     other.instance_properties == self.instance_properties and
                     other.userdata == self.userdata and
-                    other.networks == self.networks)
+                    other.networks == self.networks and
+                    other.host_key_checking == self.host_key_checking)
         return False
 
     def __repr__(self):
@@ -211,6 +213,8 @@ class ProviderPool(ConfigPool):
                                                None)
             pl.userdata = label.get('userdata', None)
             pl.networks = label.get('networks', self.networks)
+            pl.host_key_checking = label.get(
+                'host-key-checking', self.host_key_checking)
 
             top_label = full_config.labels[pl.name]
             top_label.pools.append(self)
@@ -367,6 +371,7 @@ class OpenStackProviderConfig(ProviderConfig):
             'instance-properties': dict,
             'userdata': str,
             'networks': [str],
+            'host-key-checking': bool,
         }
 
         label_min_ram = v.Schema({v.Required('min-ram'): int}, extra=True)

nodepool/driver/openstack/handler.py

@@ -217,7 +217,7 @@ class OpenStackNodeLauncher(NodeLauncher):
 
         # wait and scan the new node and record in ZooKeeper
         host_keys = []
-        if self.pool.host_key_checking:
+        if self.label.host_key_checking:
             try:
                 self.log.debug(
                     "Gathering host keys for node %s", self.node.id)

nodepool/tests/fixtures/node-host-key-checking.yaml

@@ -11,6 +11,8 @@ zookeeper-servers:
 labels:
   - name: fake-label
     min-ready: 1
+  - name: fake-label2
+    min-ready: 1
 
 providers:
   - name: fake-provider
@@ -37,6 +39,22 @@ providers:
             min-ram: 8192
             flavor-name: 'Fake'
 
+  - name: fake-provider2
+    cloud: fake
+    driver: fake
+    region-name: fake-region
+    rate: 0.0001
+    diskimages:
+      - name: fake-image
+    pools:
+      - name: main
+        max-servers: 96
+        labels:
+          - name: fake-label2
+            diskimage: fake-image
+            host-key-checking: False
+            min-ram: 8192
+
 diskimages:
   - name: fake-image
     elements:

nodepool/tests/unit/test_launcher.py

@@ -514,21 +514,29 @@ class TestLauncher(tests.DBTestCase):
                          {'key1': 'value1', 'key2': 'value2'})
 
     def test_node_host_key_checking_false(self):
-        """Test that an image and node are created"""
+        """Test that images and nodes are created"""
         configfile = self.setup_config('node-host-key-checking.yaml')
         pool = self.useNodepool(configfile, watermark_sleep=1)
         self.useBuilder(configfile)
         pool.start()
         image = self.waitForImage('fake-provider', 'fake-image')
         self.assertEqual(image.username, 'zuul')
-        nodes = self.waitForNodes('fake-label')
+        label1_nodes = self.waitForNodes('fake-label')
+        label2_nodes = self.waitForNodes('fake-label2')
 
-        self.assertEqual(len(nodes), 1)
-        self.assertEqual(nodes[0].provider, 'fake-provider')
-        self.assertEqual(nodes[0].type, ['fake-label'])
-        self.assertEqual(nodes[0].username, 'zuul')
-        # We have no host_keys because host-key-checking is False.
-        self.assertEqual(nodes[0].host_keys, [])
+        self.assertEqual(len(label1_nodes), 1)
+        self.assertEqual(label1_nodes[0].provider, 'fake-provider')
+        self.assertEqual(label1_nodes[0].type, ['fake-label'])
+        self.assertEqual(label1_nodes[0].username, 'zuul')
+        # We have no host_keys because pool.host-key-checking is False.
+        self.assertEqual(label1_nodes[0].host_keys, [])
+
+        self.assertEqual(len(label2_nodes), 1)
+        self.assertEqual(label2_nodes[0].provider, 'fake-provider2')
+        self.assertEqual(label2_nodes[0].type, ['fake-label2'])
+        self.assertEqual(label2_nodes[0].username, 'zuul')
+        # We have no host_keys because label.host-key-checking is False.
+        self.assertEqual(label2_nodes[0].host_keys, [])
 
     def test_multiple_launcher(self):
         """Test that an image and node are created with 2 launchers"""

releasenotes/notes/openstack-driver-labels-host-key-checking-f102c013040f5f15.yaml

@@ -0,0 +1,7 @@
+---
+features:
+  - |
+    Provider labels for the OpenStack driver are now able to toggle
+    :attr:`providers.[openstack].pools.labels.host-key-checking`. This
+    overrides the host-key-checking value defined by
+    :attr:`providers.[openstack].pools.host-key-checking`.