move kernel package selection to its own controller/model

autoinstall-schema.json

@@ -72,6 +72,31 @@
             },
             "additionalProperties": false
         },
+        "kernel": {
+            "type": "object",
+            "properties": {
+                "package": {
+                    "type": "string"
+                },
+                "flavor": {
+                    "type": "string"
+                }
+            },
+            "oneOf": [
+                {
+                    "type": "object",
+                    "required": [
+                        "package"
+                    ]
+                },
+                {
+                    "type": "object",
+                    "required": [
+                        "flavor"
+                    ]
+                }
+            ]
+        },
         "keyboard": {
             "type": "object",
             "properties": {

subiquity/models/kernel.py

@@ -0,0 +1,26 @@
+# Copyright 2021 Canonical, Ltd.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as
+# published by the Free Software Foundation, either version 3 of the
+# License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+
+class KernelModel:
+
+    metapkg_name = None
+
+    def render(self):
+        return {
+            'kernel': {
+                'package': self.metapkg_name,
+                },
+            }

subiquity/models/subiquity.py

@@ -30,6 +30,7 @@ from subiquitycore.utils import run_command
 
 from .filesystem import FilesystemModel
 from .identity import IdentityModel
+from .kernel import KernelModel
 from .keyboard import KeyboardModel
 from .locale import LocaleModel
 from .mirror import MirrorModel
@@ -69,6 +70,7 @@ ff02::2 ip6-allrouters
 INSTALL_MODEL_NAMES = [
     "debconf_selections",
     "filesystem",
+    "kernel",
     "keyboard",
     "mirror",
     "network",
@@ -110,6 +112,7 @@ class SubiquityModel:
         self.debconf_selections = DebconfSelectionsModel()
         self.filesystem = FilesystemModel()
         self.identity = IdentityModel()
+        self.kernel = KernelModel()
         self.keyboard = KeyboardModel(self.root)
         self.locale = LocaleModel()
         self.mirror = MirrorModel()
@@ -351,12 +354,4 @@ class SubiquityModel:
             log.debug("merging config from %s", model)
             merge_config(config, model.render())
 
-        mp_file = os.path.join(self.root, "run/kernel-meta-package")
-        if os.path.exists(mp_file):
-            with open(mp_file) as fp:
-                kernel_package = fp.read().strip()
-            config['kernel'] = {
-                'package': kernel_package,
-                }
-
         return config

subiquity/server/controllers/__init__.py

@@ -19,6 +19,7 @@ from .filesystem import FilesystemController
 from .identity import IdentityController
 from .install import InstallController
 from .keyboard import KeyboardController
+from .kernel import KernelController
 from .locale import LocaleController
 from .mirror import MirrorController
 from .network import NetworkController
@@ -40,6 +41,7 @@ __all__ = [
     'FilesystemController',
     'IdentityController',
     'InstallController',
+    'KernelController',
     'KeyboardController',
     'LateController',
     'LocaleController',

subiquity/server/controllers/kernel.py

@@ -0,0 +1,82 @@
+# Copyright 2021 Canonical, Ltd.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as
+# published by the Free Software Foundation, either version 3 of the
+# License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import os
+
+from subiquitycore.lsb_release import lsb_release
+
+from subiquity.server.controller import NonInteractiveController
+
+
+class KernelController(NonInteractiveController):
+
+    model_name = autoinstall_key = "kernel"
+    autoinstall_default = None
+    autoinstall_schema = {
+        "type": "object",
+        "properties": {
+            "package": {"type": "string"},
+            "flavor": {"type": "string"},
+        },
+        "oneOf": [
+            {
+                "type": "object",
+                "required": ["package"],
+            },
+            {
+                "type": "object",
+                "required": ["flavor"],
+            }
+        ],
+    }
+
+    def start(self):
+        mp_file = os.path.join(
+            self.app.base_model.root,
+            "run/kernel-meta-package")
+        if os.path.exists(mp_file):
+            with open(mp_file) as fp:
+                kernel_package = fp.read().strip()
+            self.model.metapkg_name = kernel_package
+        elif self.model.metapkg_name is None:
+            self.model.metapkg_name = 'linux-generic'
+
+    def load_autoinstall_data(self, data):
+        if data is None:
+            return
+        package = data.get('package')
+        flavor = data.get('flavor')
+        if package is None:
+            if flavor is None or flavor == 'generic':
+                package = 'linux-generic'
+            else:
+                if flavor is None:
+                    package = 'generic'
+                else:
+                    if flavor == 'hwe':
+                        flavor = 'generic-hwe'
+                    # Should check this package exists really but
+                    # that's a bit tricky until we get cleverer about
+                    # the apt config in general.
+                    package = 'linux-{flavor}-{release}'.format(
+                        flavor=flavor, release=lsb_release()['release'])
+        self.model.metapkg_name = package
+
+    def make_autoinstall(self):
+        return {
+            'kernel': {
+                'package': self.model.metapkg_name,
+                },
+            }

subiquity/server/server.py

@@ -178,6 +178,7 @@ class SubiquityServer(Application):
         "Debconf",
         "Locale",
         "Refresh",
+        "Kernel",
         "Keyboard",
         "Zdev",
         "Network",