add support for 'dd' image sources

I think only a core dd image source will work for now. Probably.

examples/sources/core.yaml

@@ -4,7 +4,7 @@
   locale_support: none
   name:
     en: Ubuntu Server
-  path: ubuntu-core.squashfs
+  path: pc.img
   size: 530485248
-  type: fsimage
+  type: 'dd-raw:file'
   variant: core

subiquity/common/types.py

@@ -351,6 +351,8 @@ class GuidedCapability(enum.Enum):
     CORE_BOOT_PREFER_ENCRYPTED = enum.auto()
     CORE_BOOT_PREFER_UNENCRYPTED = enum.auto()
 
+    DD = enum.auto()
+
     def is_lvm(self) -> bool:
         return self in [GuidedCapability.LVM, GuidedCapability.LVM_LUKS]
 

subiquity/models/filesystem.py

@@ -1259,6 +1259,7 @@ class FilesystemModel(object):
         self.bootloader = bootloader
         self.storage_version = 1
         self._probe_data = None
+        self.dd_target: Optional[Disk] = None
         self.reset()
 
     def reset(self):
@@ -1718,6 +1719,18 @@ class FilesystemModel(object):
         return r
 
     def render(self, mode: ActionRenderMode = ActionRenderMode.DEFAULT):
+        if self.dd_target is not None:
+            return {
+                "partitioning_commands": {
+                    "builtin": [
+                        "curtin",
+                        "block-meta",
+                        "simple",
+                        "--devices",
+                        self.dd_target.path,
+                    ],
+                },
+            }
         config = {
             "storage": {
                 "version": self.storage_version,

subiquity/server/controllers/filesystem.py

@@ -186,6 +186,19 @@ class VariationInfo:
             ),
         )
 
+    @classmethod
+    def dd(cls, name: str, min_size: int):
+        return cls(
+            name=name,
+            label=None,
+            min_size=min_size,
+            capability_info=CapabilityInfo(
+                allowed=[
+                    GuidedCapability.DD,
+                ]
+            ),
+        )
+
 
 class FilesystemController(SubiquityController, FilesystemManipulator):
     endpoint = API.storage
@@ -363,6 +376,11 @@ class FilesystemController(SubiquityController, FilesystemManipulator):
                 info = self.info_for_system(name, label, system)
                 if info is not None:
                     self._variation_info[name] = info
+            elif catalog_entry.type.startswith("dd-"):
+                min_size = variation.size
+                self._variation_info[name] = VariationInfo.dd(
+                    name=name, min_size=min_size
+                )
             else:
                 self._variation_info[name] = VariationInfo.classic(
                     name=name, min_size=variation.size
@@ -418,6 +436,9 @@ class FilesystemController(SubiquityController, FilesystemManipulator):
         spec = dict(fstype="ext4", mount="/")
         self.create_partition(device=gap.device, gap=gap, spec=spec)
 
+    def guided_dd(self, disk: ModelDisk):
+        self.model.dd_target = disk
+
     def guided_lvm(self, gap, choice: GuidedChoiceV2):
         device = gap.device
         part_align = device.alignment_data().part_align
@@ -552,6 +573,7 @@ class FilesystemController(SubiquityController, FilesystemManipulator):
     async def guided(
         self, choice: GuidedChoiceV2, reset_partition_only: bool = False
     ) -> None:
+        self.model.dd_target = None
         if choice.capability == GuidedCapability.MANUAL:
             return
 
@@ -602,6 +624,8 @@ class FilesystemController(SubiquityController, FilesystemManipulator):
             self.guided_zfs(gap, choice)
         elif choice.capability == GuidedCapability.DIRECT:
             self.guided_direct(gap)
+        elif choice.capability == GuidedCapability.DD:
+            self.guided_dd(disk)
         else:
             raise ValueError("cannot process capability")
 
@@ -1218,6 +1242,9 @@ class FilesystemController(SubiquityController, FilesystemManipulator):
                     capability = GuidedCapability.LVM_LUKS
                 else:
                     capability = GuidedCapability.LVM
+            elif name == "dd":
+                capability = GuidedCapability.DD
+                assert mode == "reformat_disk"
             elif name == "zfs":
                 capability = GuidedCapability.ZFS
             else:
@@ -1274,6 +1301,8 @@ class FilesystemController(SubiquityController, FilesystemManipulator):
                 )
             await self.run_autoinstall_guided(self.ai_data["layout"])
         elif "config" in self.ai_data:
+            if self.app.base_model.source.current.type.startswith("dd-"):
+                raise Exception("must not use config: when installing a disk image")
             # XXX in principle should there be a way to influence the
             # variation chosen here? Not with current use cases for
             # variations anyway.
@@ -1342,10 +1371,20 @@ class FilesystemController(SubiquityController, FilesystemManipulator):
         self.ensure_probing()
 
     def make_autoinstall(self):
-        rendered = self.model.render()
-        r = {"config": rendered["storage"]["config"]}
-        if "swap" in rendered:
-            r["swap"] = rendered["swap"]
+        if self.model.dd_target is None:
+            rendered = self.model.render()
+            r = {"config": rendered["storage"]["config"]}
+            if "swap" in rendered:
+                r["swap"] = rendered["swap"]
+        else:
+            r = {
+                "layout": {
+                    "name": "dd",
+                    "match": {
+                        "path": self.model.dd_target.path,
+                    },
+                },
+            }
         return r
 
     async def _pre_shutdown(self):

subiquity/server/controllers/install.py

@@ -125,7 +125,7 @@ class InstallController(SubiquityController):
         """Return configuration to be used as part of a curtin 'block-meta'
         step."""
         cfg = self.model.filesystem.render(mode=mode)
-        if device_map_path is not None:
+        if "storage" in cfg and device_map_path is not None:
             cfg["storage"]["device_map_path"] = str(device_map_path)
         return cfg
 
@@ -318,6 +318,7 @@ class InstallController(SubiquityController):
                 step_config=self.filesystem_config(
                     device_map_path=logs_dir / "device-map.json",
                 ),
+                source=source,
             )
             await run_curtin_step(
                 name="extract",

subiquity/server/controllers/source.py

@@ -134,7 +134,7 @@ class SourceController(SubiquityController):
         handler = get_handler_for_source(
             sanitize_source(self.model.get_source(variation_name))
         )
-        if self.app.opts.dry_run:
+        if handler is not None and self.app.opts.dry_run:
             handler = TrivialSourceHandler("/")
         return handler
 

subiquity/server/controllers/tests/test_filesystem.py

@@ -361,6 +361,7 @@ class TestGuided(IsolatedAsyncioTestCase):
         self.controller.supports_resilient_boot = True
         self.controller._examine_systems_task.start_sync()
         self.app.dr_cfg = DRConfig()
+        self.app.base_model.source.current.type = "fsimage"
         self.app.base_model.source.current.variations = {
             "default": CatalogEntryVariation(path="", size=1),
         }
@@ -627,6 +628,7 @@ class TestGuidedV2(IsolatedAsyncioTestCase):
         self.fsc.model = self.model = make_model(bootloader)
         self.fsc._examine_systems_task.start_sync()
         self.app.dr_cfg = DRConfig()
+        self.app.base_model.source.current.type = "fsimage"
         self.app.base_model.source.current.variations = {
             "default": CatalogEntryVariation(path="", size=1),
         }
@@ -1245,6 +1247,7 @@ class TestCoreBootInstallMethods(IsolatedAsyncioTestCase):
         # runs much more quickly than the integration test!
         self.fsc.model = model = make_model(Bootloader.UEFI)
         disk = make_disk(model)
+        self.app.base_model.source.current.type = "fsimage"
         self.app.base_model.source.current.variations = {
             "default": CatalogEntryVariation(
                 path="", size=1, snapd_system_label="prefer-encrypted"
@@ -1338,6 +1341,7 @@ class TestCoreBootInstallMethods(IsolatedAsyncioTestCase):
     async def test_from_sample_data_defective(self):
         self.fsc.model = model = make_model(Bootloader.UEFI)
         make_disk(model)
+        self.app.base_model.source.current.type = "fsimage"
         self.app.base_model.source.current.variations = {
             "default": CatalogEntryVariation(
                 path="", size=1, snapd_system_label="defective"

subiquity/server/curtin.py

@@ -148,6 +148,7 @@ class _DryRunCurtinCommand(_CurtinCommand):
 
     def make_command(self, command, *args, config=None):
         if command == "install":
+            log.debug("creating substitute for curtin install %s", args)
             # Lookup the log file from the config if specified
             try:
                 with open(config, mode="r") as fh:

subiquity/ui/views/filesystem/guided.py

@@ -381,7 +381,10 @@ class GuidedDiskSelectionView(BaseView):
                 else:
                     capability = GuidedCapability.LVM
             else:
-                capability = GuidedCapability.DIRECT
+                if GuidedCapability.DD in target.allowed:
+                    capability = GuidedCapability.DD
+                else:
+                    capability = GuidedCapability.DIRECT
             choice = GuidedChoiceV2(
                 target=target,
                 capability=capability,

subiquitycore/ui/table.py

@@ -242,7 +242,7 @@ def _compute_widths_for_size(maxcol, table_rows, colspecs, default_spacing):
             widths[underlying_i] = max(w, widths.get(underlying_i, 0))
 
     # count the columns...
-    colcount = max(widths.keys()) // 2 + 1
+    colcount = max(widths.keys(), default=1) // 2 + 1
     if unpacked_user_indices:
         colcount = max(colcount, max(unpacked_user_indices) + 1)