Make SplitArtifacts= take a list of values

This allows more precision on which artifacts are actually split out of
the image and placed into the output directory. Defaults to splitting
the UKI, vmlinuz and the initrd out.

mkosi/__init__.py

@@ -50,6 +50,7 @@
 from mkosi.config import (
     PACKAGE_GLOBS,
     Args,
+    ArtifactOutput,
     Bootloader,
     Cacheonly,
     Compression,
@@ -2100,8 +2101,11 @@ def make_uki(
         output,
     )
 
-    extract_pe_section(context, output, ".linux", context.staging / context.config.output_split_kernel)
-    extract_pe_section(context, output, ".initrd", context.staging / context.config.output_split_initrd)
+    if ArtifactOutput.kernel in context.config.split_artifacts:
+        extract_pe_section(context, output, ".linux", context.staging / context.config.output_split_kernel)
+
+    if ArtifactOutput.initrd in context.config.split_artifacts:
+        extract_pe_section(context, output, ".initrd", context.staging / context.config.output_split_initrd)
 
 
 def compressor_command(context: Context, compression: Compression) -> list[PathString]:
@@ -2178,6 +2182,9 @@ def get_uki(context: Context) -> Optional[Path]:
 
 
 def copy_uki(context: Context) -> None:
+    if ArtifactOutput.uki not in context.config.split_artifacts:
+        return
+
     if (context.staging / context.config.output_split_uki).exists():
         return
 
@@ -2186,6 +2193,9 @@ def copy_uki(context: Context) -> None:
 
 
 def copy_vmlinuz(context: Context) -> None:
+    if ArtifactOutput.kernel not in context.config.split_artifacts:
+        return
+
     if (context.staging / context.config.output_split_kernel).exists():
         return
 
@@ -2201,6 +2211,9 @@ def copy_vmlinuz(context: Context) -> None:
 
 
 def copy_initrd(context: Context) -> None:
+    if ArtifactOutput.initrd not in context.config.split_artifacts:
+        return
+
     if not want_initrd(context):
         return
 
@@ -3378,7 +3391,7 @@ def make_extension_image(context: Context, output: Path) -> None:
         ]  # fmt: skip
     if context.config.sector_size:
         cmdline += ["--sector-size", str(context.config.sector_size)]
-    if context.config.split_artifacts:
+    if ArtifactOutput.partitions in context.config.split_artifacts:
         cmdline += ["--split=yes"]
 
     with complete_step(f"Building {context.config.output_format} extension image"):
@@ -3400,7 +3413,7 @@ def make_extension_image(context: Context, output: Path) -> None:
 
     logging.debug(json.dumps(j, indent=4))
 
-    if context.config.split_artifacts:
+    if ArtifactOutput.partitions in context.config.split_artifacts:
         for p in (Partition.from_dict(d) for d in j):
             if p.split_path:
                 maybe_compress(context, context.config.compress_output, p.split_path)
@@ -3645,7 +3658,7 @@ def build_image(context: Context) -> None:
     partitions = make_disk(context, msg="Formatting ESP/XBOOTLDR partitions")
     grub_bios_setup(context, partitions)
 
-    if context.config.split_artifacts:
+    if ArtifactOutput.partitions in context.config.split_artifacts:
         make_disk(context, split=True, msg="Extracting partitions")
 
     copy_nspawn_settings(context)

mkosi/config.py

@@ -499,7 +499,18 @@ def native(cls) -> "Architecture":
         return cls.from_uname(platform.machine())
 
 
-def parse_boolean(s: str) -> bool:
+class ArtifactOutput(enum.IntFlag):
+    uki = 1
+    kernel = 2
+    initrd = 4
+    partitions = 8
+
+    # Set a high bit to prevent these from showing up when only the previous values are set
+    no = 0b10000000000000000000000000000000 | uki | kernel | initrd
+    yes = 0b10000000000000000000000000000000 | uki | kernel | initrd | partitions
+
+
+def try_parse_boolean(s: str) -> Optional[bool]:
     "Parse 1/true/yes/y/t/on as true and 0/false/no/n/f/off/None as false"
 
     s_l = s.lower()
@@ -509,7 +520,16 @@ def parse_boolean(s: str) -> bool:
     if s_l in {"0", "false", "no", "n", "f", "off", "never"}:
         return False
 
-    die(f"Invalid boolean literal: {s!r}")
+    return None
+
+
+def parse_boolean(s: str) -> bool:
+    value = try_parse_boolean(s)
+
+    if value is None:
+        die(f"Invalid boolean literal: {s!r}")
+
+    return value
 
 
 def parse_path(
@@ -1291,6 +1311,25 @@ def config_parse_key_source(value: Optional[str], old: Optional[KeySource]) -> O
     return KeySource(type=type, source=source)
 
 
+def config_parse_artifact_output(
+    value: Optional[str], old: Optional[ArtifactOutput]
+) -> Optional[ArtifactOutput]:
+    if not value:
+        return None
+
+    # Keep for backwards compatibility
+    boolean_value = try_parse_boolean(value)
+    if boolean_value is not None:
+        return ArtifactOutput.yes if boolean_value else ArtifactOutput.no
+
+    try:
+        new = ArtifactOutput(ArtifactOutput[value])
+    except KeyError:
+        die(f"'{value}' is not a valid {ArtifactOutput.__name__}")
+
+    return old | new if old else new
+
+
 class SettingScope(StrEnum):
     # Not passed down to subimages
     local = enum.auto()
@@ -1596,7 +1635,7 @@ class Config:
     output_mode: Optional[int]
     image_id: Optional[str]
     image_version: Optional[str]
-    split_artifacts: bool
+    split_artifacts: ArtifactOutput
     repart_dirs: list[Path]
     sysupdate_dir: Optional[Path]
     sector_size: Optional[int]
@@ -2292,11 +2331,11 @@ def parse_ini(path: Path, only_sections: Collection[str] = ()) -> Iterator[tuple
     ),
     ConfigSetting(
         dest="split_artifacts",
-        metavar="BOOL",
         nargs="?",
         section="Output",
-        parse=config_parse_boolean,
-        help="Generate split partitions",
+        parse=config_parse_artifact_output,
+        default=ArtifactOutput.no,
+        help="Split artifacts out of the final image",
     ),
     ConfigSetting(
         dest="repart_dirs",
@@ -4429,6 +4468,10 @@ def line_join_list(array: Iterable[object]) -> str:
     return "\n                                     ".join(str(item) for item in array) if array else "none"
 
 
+def int_flag_names(flag: enum.IntFlag) -> str:
+    return none_to_none(flag.name).replace("|", "\n                                     ")
+
+
 def format_bytes(num_bytes: int) -> str:
     if num_bytes >= 1024**3:
         return f"{num_bytes/1024**3 :0.1f}G"
@@ -4508,7 +4551,7 @@ def summary(config: Config) -> str:
                         Output Mode: {format_octal_or_default(config.output_mode)}
                            Image ID: {config.image_id}
                       Image Version: {config.image_version}
-                    Split Artifacts: {yes_no(config.split_artifacts)}
+                    Split Artifacts: {int_flag_names(config.split_artifacts)}
                  Repart Directories: {line_join_list(config.repart_dirs)}
                         Sector Size: {none_to_default(config.sector_size)}
                             Overlay: {yes_no(config.overlay)}

mkosi/resources/man/mkosi.1.md

@@ -596,13 +596,20 @@ boolean argument: either `1`, `yes`, or `true` to enable, or `0`, `no`,
     invoked. The image ID is automatically added to `/usr/lib/os-release`.
 
 `SplitArtifacts=`, `--split-artifacts`
-:   If specified and building a disk image, pass `--split=yes` to systemd-repart
-    to have it write out split partition files for each configured partition.
-    Read the [man](https://www.freedesktop.org/software/systemd/man/systemd-repart.html#--split=BOOL)
+:   The artifact types to split out of the final image. A comma-delimited
+    list consisting of `uki`, `kernel`, `initrd` and `partitions`. When
+    building a bootable image `kernel` and `initrd` correspond to their
+    artifact found in the image (or in the UKI), while `uki` copies out the
+    entire UKI.
+
+    When building a disk image and `partitions` is specified,
+    pass `--split=yes` to systemd-repart to have it write out split partition
+    files for each configured partition. Read the
+    [man](https://www.freedesktop.org/software/systemd/man/systemd-repart.html#--split=BOOL)
     page for more information. This is useful in A/B update scenarios where
     an existing disk image shall be augmented with a new version of a
     root or `/usr` partition along with its Verity partition and unified
-    kernel.
+    kernel. By default `uki`, `kernel` and `initrd` are split out.
 
 `RepartDirectories=`, `--repart-dir=`
 :   Paths to directories containing systemd-repart partition definition
@@ -2229,7 +2236,7 @@ current working directory. The following scripts are supported:
 * If **`mkosi.clean`** (`CleanScripts=`) exists, it is executed right
   after the outputs of a previous build have been cleaned up. A clean
   script can clean up any outputs that mkosi does not know about (e.g.
-  artifacts from `SplitArtifacts=yes` or RPMs built in a build script).
+  artifacts from `SplitArtifacts=partitions` or RPMs built in a build script).
   Note that this script does not use the tools tree even if one is configured.
 
 * If **`mkosi.version`** exists and is executable, it is run during

mkosi/sysupdate.py

@@ -4,15 +4,15 @@
 import sys
 from pathlib import Path
 
-from mkosi.config import Args, Config
+from mkosi.config import Args, ArtifactOutput, Config
 from mkosi.log import die
 from mkosi.run import run
 from mkosi.types import PathString
 
 
 def run_sysupdate(args: Args, config: Config) -> None:
-    if not config.split_artifacts:
-        die("SplitArtifacts= must be enabled to be able to use mkosi sysupdate")
+    if ArtifactOutput.partitions not in config.split_artifacts:
+        die("SplitArtifacts=partitions must be set to be able to use mkosi sysupdate")
 
     if not config.sysupdate_dir:
         die(

tests/test_config.py

@@ -12,6 +12,7 @@
 from mkosi import expand_kernel_specifiers
 from mkosi.config import (
     Architecture,
+    ArtifactOutput,
     Compression,
     Config,
     ConfigFeature,
@@ -235,19 +236,19 @@ def test_parse_config(tmp_path: Path) -> None:
     with chdir(d):
         _, [config] = parse_config()
         assert config.bootable == ConfigFeature.auto
-        assert config.split_artifacts is False
+        assert config.split_artifacts == ArtifactOutput.no
 
         # Passing the directory should include both the main config file and the dropin.
         _, [config] = parse_config(["--include", os.fspath(d / "abc")] * 2)
         assert config.bootable == ConfigFeature.enabled
-        assert config.split_artifacts is True
+        assert config.split_artifacts == ArtifactOutput.yes
         # The same extra config should not be parsed more than once.
         assert config.build_packages == ["abc"]
 
         # Passing the main config file should not include the dropin.
         _, [config] = parse_config(["--include", os.fspath(d / "abc/mkosi.conf")])
         assert config.bootable == ConfigFeature.enabled
-        assert config.split_artifacts is False
+        assert config.split_artifacts == ArtifactOutput.no
 
     (d / "mkosi.images").mkdir()
 
@@ -1277,3 +1278,51 @@ def test_mkosi_version_executable(tmp_path: Path) -> None:
     with chdir(d):
         _, [config] = parse_config()
         assert config.image_version == "1.2.3"
+
+
+def test_split_artifacts(tmp_path: Path) -> None:
+    d = tmp_path
+
+    (d / "mkosi.conf").write_text(
+        """
+        [Output]
+        SplitArtifacts=uki
+        """
+    )
+
+    with chdir(d):
+        _, [config] = parse_config()
+        assert config.split_artifacts == ArtifactOutput.uki
+
+    (d / "mkosi.conf").write_text(
+        """
+        [Output]
+        SplitArtifacts=uki
+        SplitArtifacts=kernel
+        SplitArtifacts=initrd
+        """
+    )
+
+    with chdir(d):
+        _, [config] = parse_config()
+        assert config.split_artifacts == ArtifactOutput.uki | ArtifactOutput.kernel | ArtifactOutput.initrd
+
+
+def test_split_artifacts_compat(tmp_path: Path) -> None:
+    d = tmp_path
+
+    with chdir(d):
+        _, [config] = parse_config()
+        assert config.split_artifacts == ArtifactOutput.no
+
+    (d / "mkosi.conf").write_text(
+        """
+        [Output]
+        SplitArtifacts=yes
+        """
+    )
+
+    with chdir(d):
+        "mkosi.conf"
+        _, [config] = parse_config()
+        assert config.split_artifacts == ArtifactOutput.yes

tests/test_json.py

@@ -11,6 +11,7 @@
 from mkosi.config import (
     Architecture,
     Args,
+    ArtifactOutput,
     BiosBootloader,
     Bootloader,
     Cacheonly,
@@ -333,7 +334,7 @@ def test_config() -> None:
                 }
             ],
             "SourceDateEpoch": 12345,
-            "SplitArtifacts": true,
+            "SplitArtifacts": 3,
             "Ssh": false,
             "SshCertificate": "/path/to/cert",
             "SshKey": null,
@@ -533,7 +534,7 @@ def test_config() -> None:
         sign_expected_pcr_certificate=Path("/my/cert"),
         skeleton_trees=[ConfigTree(Path("/foo/bar"), Path("/")), ConfigTree(Path("/bar/baz"), Path("/qux"))],
         source_date_epoch=12345,
-        split_artifacts=True,
+        split_artifacts=ArtifactOutput.uki | ArtifactOutput.kernel,
         ssh=False,
         ssh_certificate=Path("/path/to/cert"),
         ssh_key=None,