conf: Remove deprecated 'null_kernel' opt

This flag was deprecated in a previous cycle. The flag and any uses of
it can now be removed.

Change-Id: Ie26f34b4f435eeb378b88f0c48f844b511696eb9

nova/compute/api.py

@@ -408,13 +408,14 @@ class API(base.Base):
                                    image):
         """Choose kernel and ramdisk appropriate for the instance.
 
-        The kernel and ramdisk can be chosen in one of three ways:
+        The kernel and ramdisk can be chosen in one of two ways:
 
             1. Passed in with create-instance request.
 
-            2. Inherited from image.
+            2. Inherited from image metadata.
 
-            3. Forced to None by using `null_kernel` FLAG.
+        If inherited from image metadata, and if that image metadata value is
+        set to 'nokernel', both kernel and ramdisk will default to None.
         """
         # Inherit from image if not specified
         image_properties = image.get('properties', {})
@@ -425,8 +426,8 @@ class API(base.Base):
         if ramdisk_id is None:
             ramdisk_id = image_properties.get('ramdisk_id')
 
-        # Force to None if using null_kernel
+        # Force to None if kernel_id indicates that a kernel is not to be used
-        if kernel_id == str(CONF.null_kernel):
+        if kernel_id == 'nokernel':
             kernel_id = None
             ramdisk_id = None
 

nova/conf/compute.py

@@ -68,23 +68,6 @@ Possible values:
   here, since the snapshots that are created from the base images
   doesn't need them.
 * Default list: ['cache_in_nova', 'bittorrent']
-"""),
-    cfg.StrOpt('null_kernel',
-        default='nokernel',
-        deprecated_for_removal=True,
-        deprecated_since='15.0.0',
-        deprecated_reason="""
-When an image is booted with the property 'kernel_id' with the value
-'nokernel', Nova assumes the image doesn't require an external kernel and
-ramdisk. This option allows user to change the API behaviour which should not
-be allowed and this value "nokernel" should be hard coded.
-""",
-        help="""
-This option is used to decide when an image should have no external
-ramdisk or kernel. By default this is set to 'nokernel', so when an
-image is booted with the property 'kernel_id' with the value
-'nokernel', Nova assumes the image doesn't require an external kernel
-and ramdisk.
 """),
     cfg.StrOpt('multi_instance_display_name_template',
         default='%(name)s-%(count)d',

nova/tests/functional/regressions/test_bug_1558866.py

@@ -53,8 +53,8 @@ class TestServerGet(test.TestCase):
                  'container_format': 'raw',
                  'disk_format': 'raw',
                  'size': '25165824',
-                 'properties': {'kernel_id': CONF.null_kernel,
+                 'properties': {'kernel_id': 'nokernel',
-                                'ramdisk_id': CONF.null_kernel,
+                                'ramdisk_id': 'nokernel',
                                 'architecture': 'x64'}}
         self.image_id = image_service.create(None, image)['id']
         self.flavor_id = self.api.get_flavors()[0]['id']

nova/tests/unit/image/fake.py

@@ -53,8 +53,8 @@ class _FakeImageService(object):
                  'disk_format': 'raw',
                  'size': '25165824',
                  'properties': {
-                    'kernel_id': CONF.null_kernel,
+                    'kernel_id': 'nokernel',
-                    'ramdisk_id': CONF.null_kernel,
+                    'ramdisk_id': 'nokernel',
                     'architecture': obj_fields.Architecture.X86_64}}
 
         image2 = {'id': 'a2459075-d96c-40d5-893e-577ff92e721c',
@@ -68,8 +68,8 @@ class _FakeImageService(object):
                  'container_format': 'ami',
                  'disk_format': 'ami',
                  'size': '58145823',
-                 'properties': {'kernel_id': CONF.null_kernel,
+                 'properties': {'kernel_id': 'nokernel',
-                                'ramdisk_id': CONF.null_kernel}}
+                                'ramdisk_id': 'nokernel'}}
 
         image3 = {'id': '76fa36fc-c930-4bf3-8c8a-ea2a2420deb6',
                  'name': 'fakeimage123456',
@@ -82,8 +82,8 @@ class _FakeImageService(object):
                  'container_format': 'bare',
                  'disk_format': 'raw',
                  'size': '83594576',
-                 'properties': {'kernel_id': CONF.null_kernel,
+                 'properties': {'kernel_id': 'nokernel',
-                                'ramdisk_id': CONF.null_kernel}}
+                                'ramdisk_id': 'nokernel'}}
 
         image4 = {'id': 'cedef40a-ed67-4d10-800e-17455edce175',
                  'name': 'fakeimage123456',
@@ -96,8 +96,8 @@ class _FakeImageService(object):
                  'container_format': 'ami',
                  'disk_format': 'ami',
                  'size': '84035174',
-                 'properties': {'kernel_id': CONF.null_kernel,
+                 'properties': {'kernel_id': 'nokernel',
-                                'ramdisk_id': CONF.null_kernel}}
+                                'ramdisk_id': 'nokernel'}}
 
         image5 = {'id': 'c905cedb-7281-47e4-8a62-f26bc5fc4c77',
                  'name': 'fakeimage123456',
@@ -126,8 +126,8 @@ class _FakeImageService(object):
                  'disk_format': 'vhd',
                  'size': '49163826',
                  'properties': {
-                    'kernel_id': CONF.null_kernel,
+                    'kernel_id': 'nokernel',
-                    'ramdisk_id': CONF.null_kernel,
+                    'ramdisk_id': 'nokernel',
                     'architecture': obj_fields.Architecture.X86_64,
                     'auto_disk_config': 'False'}}
 
@@ -143,8 +143,8 @@ class _FakeImageService(object):
                  'disk_format': 'vhd',
                  'size': '74185822',
                  'properties': {
-                    'kernel_id': CONF.null_kernel,
+                    'kernel_id': 'nokernel',
-                    'ramdisk_id': CONF.null_kernel,
+                    'ramdisk_id': 'nokernel',
                     'architecture': obj_fields.Architecture.X86_64,
                     'auto_disk_config': 'True'}}
 

releasenotes/notes/remove-deprecated-compute-opts-bc935162bc4723ac.yaml

@@ -0,0 +1,10 @@
+---
+upgrade:
+  - |
+    The following deprecated configuration options have been removed from the
+    ``compute`` section of ``nova.conf``:
+
+    - ``null_kernel``
+
+    These were deprecated in the 15.0.0 release as they allowed for
+    inconsistent API behavior across deployments.