From 4ebd05d660ebece06ccb7872310127c46b24cb5d Mon Sep 17 00:00:00 2001
From: Matt Riedemann <mriedem.os@gmail.com>
Date: Mon, 1 May 2017 11:25:13 -0400
Subject: [PATCH] db api: add service_get_by_uuid

This is going to be used by the Service.get_by_uuid method
which will later be used by the HostAPI to uniquely lookup
a service within a cell.

Part of blueprint service-hyper-uuid-in-api

Change-Id: Iff58296d5b05670116d4e0dc7846a260c48d84ed
---
 nova/db/api.py                    |  7 +++++++
 nova/db/sqlalchemy/api.py         | 11 +++++++++++
 nova/tests/unit/db/test_db_api.py | 16 ++++++++++++++++
 3 files changed, 34 insertions(+)

diff --git a/nova/db/api.py b/nova/db/api.py
index 83d7b10b1846..e0e01321f7a3 100644
--- a/nova/db/api.py
+++ b/nova/db/api.py
@@ -112,6 +112,13 @@ def service_get(context, service_id):
     return IMPL.service_get(context, service_id)
 
 
+def service_get_by_uuid(context, service_uuid):
+    """Get a service by it's uuid or raise ServiceNotFound if it does not
+    exist.
+    """
+    return IMPL.service_get_by_uuid(context, service_uuid)
+
+
 def service_get_minimum_version(context, binary):
     """Get the minimum service version in the database."""
     return IMPL.service_get_minimum_version(context, binary)
diff --git a/nova/db/sqlalchemy/api.py b/nova/db/sqlalchemy/api.py
index a5c0720d1769..f3bb21cd02de 100644
--- a/nova/db/sqlalchemy/api.py
+++ b/nova/db/sqlalchemy/api.py
@@ -475,6 +475,17 @@ def service_get(context, service_id):
     return result
 
 
+@pick_context_manager_reader
+def service_get_by_uuid(context, service_uuid):
+    query = model_query(context, models.Service).filter_by(uuid=service_uuid)
+
+    result = query.first()
+    if not result:
+        raise exception.ServiceNotFound(service_id=service_uuid)
+
+    return result
+
+
 @pick_context_manager_reader_allow_async
 def service_get_minimum_version(context, binaries):
     min_versions = context.session.query(
diff --git a/nova/tests/unit/db/test_db_api.py b/nova/tests/unit/db/test_db_api.py
index 33af2d768472..cd13d1a684b9 100644
--- a/nova/tests/unit/db/test_db_api.py
+++ b/nova/tests/unit/db/test_db_api.py
@@ -3572,6 +3572,22 @@ class ServiceTestCase(test.TestCase, ModelsObjectComparatorMixin):
         self._assertEqualObjects(service1, real_service1,
                                  ignored_keys=['compute_node'])
 
+    def test_service_get_by_uuid(self):
+        service1 = self._create_service({'uuid': uuidsentinel.service1_uuid})
+        self._create_service({'host': 'some_other_fake_host',
+                              'uuid': uuidsentinel.other_uuid})
+        real_service1 = db.service_get_by_uuid(
+            self.ctxt, uuidsentinel.service1_uuid)
+        self._assertEqualObjects(service1, real_service1,
+                                 ignored_keys=['compute_node'])
+
+    def test_service_get_by_uuid_not_found(self):
+        """Asserts that ServiceNotFound is raised if a service is not found by
+        a given uuid.
+        """
+        self.assertRaises(exception.ServiceNotFound, db.service_get_by_uuid,
+                          self.ctxt, uuidsentinel.service_not_found)
+
     def test_service_get_minimum_version(self):
         self._create_service({'version': 1,
                               'host': 'host3',