node_tag_exists(): raise exception if bad node

To make tags consistent with traits, change db.api.node_tag_exists()
to raise a NodeNotFound exception if the node doesn't exist.

This is a follow up to bbff319f0226af11af3c2864ad8f678abef6dcdb.

Change-Id: Id0ddf448d97b5ac22ef5dc27154a1b229514a968
Partial-Bug:#1526266

4 files changed, 10 insertions, 2 deletions

diff --git a/ironic/db/api.py b/ironic/db/api.py
index a9ab47a70..4d81207a5 100644
--- a/ironic/db/api.py
+++ b/ironic/db/api.py
@@ -662,6 +662,7 @@ class Connection(object):
         :param node_id: The id of a node.
         :param tag: A tag string.
         :returns: True if the tag exists otherwise False.
+        :raises: NodeNotFound if the node is not found.
         """
 
     @abc.abstractmethod
diff --git a/ironic/db/sqlalchemy/api.py b/ironic/db/sqlalchemy/api.py
index 3e5aaa117..020151520 100644
--- a/ironic/db/sqlalchemy/api.py
+++ b/ironic/db/sqlalchemy/api.py
@@ -968,6 +968,7 @@ class Connection(api.Connection):
                 raise exception.NodeTagNotFound(node_id=node_id, tag=tag)
 
     def node_tag_exists(self, node_id, tag):
+        self._check_node_exists(node_id)
         q = model_query(models.NodeTag).filter_by(node_id=node_id, tag=tag)
         return model_query(q.exists()).scalar()
 
diff --git a/ironic/tests/unit/db/test_node_tags.py b/ironic/tests/unit/db/test_node_tags.py
index 38c22e4a1..b2903b1d5 100644
--- a/ironic/tests/unit/db/test_node_tags.py
+++ b/ironic/tests/unit/db/test_node_tags.py
@@ -108,3 +108,7 @@ class DbNodeTagTestCase(base.DbTestCase):
     def test_node_tag_not_exists(self):
         ret = self.dbapi.node_tag_exists(self.node.id, 'tag1')
         self.assertFalse(ret)
+
+    def test_node_tag_node_not_exist(self):
+        self.assertRaises(exception.NodeNotFound,
+                          self.dbapi.node_tag_exists, '123', 'tag1')
diff --git a/ironic/tests/unit/db/test_nodes.py b/ironic/tests/unit/db/test_nodes.py
index ff09b62d9..473b61647 100644
--- a/ironic/tests/unit/db/test_nodes.py
+++ b/ironic/tests/unit/db/test_nodes.py
@@ -353,7 +353,8 @@ class DbNodeTestCase(base.DbTestCase):
 
         self.assertTrue(self.dbapi.node_tag_exists(node.id, tag.tag))
         self.dbapi.destroy_node(node.id)
-        self.assertFalse(self.dbapi.node_tag_exists(node.id, tag.tag))
+        self.assertRaises(exception.NodeNotFound,
+                          self.dbapi.node_tag_exists, node.id, tag.tag)
 
     def test_tags_get_destroyed_after_destroying_a_node_by_uuid(self):
         node = utils.create_test_node()
@@ -362,7 +363,8 @@ class DbNodeTestCase(base.DbTestCase):
 
         self.assertTrue(self.dbapi.node_tag_exists(node.id, tag.tag))
         self.dbapi.destroy_node(node.uuid)
-        self.assertFalse(self.dbapi.node_tag_exists(node.id, tag.tag))
+        self.assertRaises(exception.NodeNotFound,
+                          self.dbapi.node_tag_exists, node.id, tag.tag)
 
     def test_volume_connector_get_destroyed_after_destroying_a_node(self):
         node = utils.create_test_node()