rpm-ostree/docs/manual/treefile.md
Colin Walters 00bd491fe2 treefile: Support multiple includes
I'm working on having Silverblue inherit from Fedora CoreOS.  But
conceptually it also inherits from (parts of) Workstation.
It is just easier if we support multiple inheritance, then I don't
need to think too hard about how to make it a single inheritance chain.

Closes: #1870
Approved by: jlebon
2019-07-18 22:40:59 +00:00

14 KiB

Treefile

A "treefile" is a made up term for a JSON-formatted specification used as input to rpm-ostree compose tree to bind "set of RPMs with configuration" to "OSTree commit".

It's recommended to keep them in git, and set up a CI system like Jenkins to operate on them as it changes.

It supports the following parameters:

  • ref: string, mandatory: Holds a string which will be the name of the branch for the content.

  • gpg-key (or gpg_key): string, optional: Key ID for GPG signing; the secret key must be in the home directory of the building user. Defaults to none.

  • repos array of strings, mandatory: Names of yum repositories to use, from any files that end in .repo, in the same directory as the treefile. rpm-ostree compose tree does not use the system /etc/yum.repos.d, because it's common to want to compose a target system distinct from the one the host sytem is running.

  • selinux: boolean, optional: Defaults to true. If false, then no SELinux labeling will be performed on the server side.

  • boot-location (or boot_location): string, optional: There are 2 possible values:

    • "new": A misnomer, this value is no longer "new". Kernel data goes in /usr/lib/ostree-boot in addition to /usr/lib/modules. This is the default; use it if you have a need to care about upgrading from very old versions of libostree.
    • "modules": Kernel data goes just in /usr/lib/modules. Use this for new systems, and systems that don't need to be upgraded from very old libostree versions.
  • etc-group-members: Array of strings, optional: Unix groups in this list will be stored in /etc/group instead of /usr/lib/group. Use this option for groups for which humans should be a member.

  • install-langs: Array of strings, optional. This sets the RPM _install_langs macro. Set this to e.g. ["en_US", "fr_FR"].

  • mutate-os-release: String, optional. This causes rpm-ostree to change the VERSION and PRETTY_NAME fields to include the ostree version, and adds a specific OSTREE_VERSION key that can be easier for processes to query than looking via ostree. The actual value of this key represents the baked string that gets substituted out for the final OSTree version.

  • documentation: boolean, optional. If this is set to false it sets the RPM transaction flag "nodocs" which makes yum/rpm not install files marked as documentation. The default is true.

  • packages: Array of strings, mandatory: Set of installed packages. comps groups are currently not supported due to walters having issues with libcomp: 36d18b4905

  • packages-$basearch: Array of strings, optional: Set of installed packages, used only if $basearch matches the target architecture name.

  • ostree-layers: Array of strings, optional: After all packages are unpacked, check out these OSTree refs, which must already be in the destination repository. Any conflicts with packages will be an error.

  • ostree-override-layers: Array of strings, optional: Like above, but any files present in packages and prior layers will be silently overriden. This is useful for development builds to replace parts of the base tree.

  • bootstrap_packages: Array of strings, optional: Deprecated; you should now just include this set in the main packages array.

  • recommends: boolean, optional: Install Recommends, defaults to true.

  • units: Array of strings, optional: Systemd units to enable by default

  • default-target (or default_target): String, optional: Set the default systemd target.

  • initramfs-args: Array of strings, optional. Passed to the initramfs generation program (presently dracut). An example use case for this with Dracut is --filesystems xfs,ext4 to ensure specific filesystem drivers are included. If not specified, --no-hostonly will be used.

  • remove-files: Array of files to delete from the generated tree.

  • remove-from-packages: Array, optional: Delete from specified packages files which match the provided array of regular expressions. This is safer than remove-files as it allows finer grained control with less risk of too-wide regular expressions.

    Each array element is an array, whose first member is a package name, and subsequent members are regular expressions (compatible with JavaScript).

    Example: remove-from-packages: [["cpio", "/usr/share/.*"], ["dhclient", "/usr/lib/.*", "/usr/share/.*"]]

    Note this does not alter the RPM database, so rpm -V will complain.

  • preserve-passwd: boolean, optional: Defaults to true. If enabled, and check-passwd has a type other than file, copy the /etc/passwd (and /usr/lib/passwd) files from the previous commit if they exist. If check-passwd has the file type, then the data is preserved from that file to /usr/lib/passwd. This helps ensure consistent uid/gid allocations across builds. However, it does mean that removed users will exist in the passwd database forever.

  • check-passwd: Object, optional: Checks to run against the new passwd file before accepting the tree. All the entries specified should exist (unless ignored) and have the same values or the compose will fail. There are four types: none (for no checking), previous (to check against the passwd file in the previous commit), file (to check against another passwd file), and data to specify the relevant passwd data in the json itself. Note that if you choose file, and preserve-passwd is true then the data will be copied from the referenced file and not the previous commit.

    Example: check-passwd: { "type": "none" } Example: check-passwd: { "type": "previous" } Example: check-passwd: { "type": "file", "filename": "local-passwd" } Example: check-passwd: { "type": "data", "entries": { "bin": 1, "adm": [3, 4] } } See also: ignore-remove-users

  • check-groups: Object, optional: Checks to run against the new group file before accepting the tree. All the entries specified should exist (unless ignored) and have the same values or the compose will fail. There are four types: none (for no checking), previous (to check against the group file in the previous commit), file (to check against another group file), and data to specify the relevant group data in the json itself. Note that if you choose file, and preserve-passwd is true then the data will be copied from the referenced file and not the previous commit.

    Example: check-groups: { "type": "none" } Example: check-groups: { "type": "previous" } Example: check-groups: { "type": "file", "filename": "local-group" } Example: check-groups: { "type": "data", "entries": { "bin": 1, "adm": 4 } } See also: ignore-remove-groups

  • ignore-removed-users: Array, optional: Users to ignore if they are missing in the new passwd file. If an entry of * is specified then any user can be removed without failing the compose.

    Example: ignore-removed-users: ["avahi-autoipd", "tss"]

  • ignore-removed-groups: Array, optional: Groups to ignore if they are missing in the new group file. If an entry of * is specified then any group can be removed without failing the compose.

    Example: ignore-removed-groups: ["avahi"]

  • releasever: String, optional: Used to set the librepo $releasever variable, commonly used in yum repo files.

    Example: releasever: "26"

  • automatic-version-prefix (or automatic_version_prefix): String, optional: Set the prefix for versions on the commits. The idea is that if the previous commit on the branch to the doesn't match the prefix, or doesn't have a version, then the new commit will have the version as specified. If the prefix matches exactly, then we append ".1". Otherwise we parse the number after the prefix and increment it by one and then append that to the prefix.

    A current date/time may also be passed through automatic-version-prefix, by including a date tag in the prefix as such: <date:format>, where format is a string with date formats such as %Y (year), %m (month), etc. The full list of supported formats is found in the GLib API. Including a date/time format will automatically append a .0 to the version, if not present in the prefix, which resets to .0 if the date (or prefix) changes.

    This means that on an empty branch with an automatic-version-prefix of "22" the first three commits would get the versions: "22", "22.1", "22.2". Some example progressions are shown:

    automatic-version-prefix version progression
    22 22, 22.1, 22.2, ...
    22.1 22.1.1, 22.1.2, 22.1.3, ...
    22.<date:%Y> 22.2019.0, 22.2019.1, 22.2020.0, ...
    22.<date:%Y>.1 22.2019.1.0, 22.2019.1.1, 22.2020.1.0, ...

    Example: automatic-version-prefix: "22.0"

  • add-commit-metadata: Map<String, Object>, optional: Metadata to inject as part of composed commits. Keys inserted here can still be overridden at the command line with --add-metadata-string or --add-metadata-from-json.

  • postprocess-script: String, optional: Full filesystem path to a script that will be executed in the context of the target tree. The script will be copied into the target into /tmp, and run as a container (a restricted chroot, with no network access). After execution is complete, it will be deleted.

    It is strongly recommended to avoid using this except as a last resort. Having the system generated through RPMs allows administrators to understand the inputs to the system. Any new files created through this mechanism will not have the versioning inherent in RPM.

    Only the script file will be copied in; thus if it has any dependencies, on data beyond what is in the target tree, you must embed them in the binary itself.

    An example use for this is working around bugs in the input RPMs that are hard to fix in stable releases.

    Note this does not alter the RPM database, so rpm -V will complain.

    If you want to depend on network access, or tools not in the target host, you can use the split-up rpm-ostree compose install and rpm-ostree compose postprocess/commit commands.

  • postprocess: array of string, optional: This is an inline script variant of postprocess-script that is also an array, so it works correctly with inheritance. If both postprocess-script and postprocess are provided, then postprocess-script will be executed after all other postprocess.

  • include: string or array of string, optional: Path(s) to treefiles which will be used as an inheritance base. The semantics for inheritance are: Non-array values in child values override parent values. Array values are concatenated. Filenames will be resolved relative to the including treefile. Since rpm-ostree 2019.5, this value may also be an array of strings. Including the same file multiple times is an error.

  • container: boolean, optional: Defaults to false. If true, then rpm-ostree will not do any special handling of kernel, initrd or the /boot directory. This is useful if the target for the tree is some kind of container which does not have its own kernel.

  • add-files: Array, optional: Copy external files to the rootfs.

    Each array element is an array, whose first member is the source file name, and the second element is the destination name. The source file must be in the same directory as the treefile.

    Example: "add-files": [["bar", "/usr/share/bar"], ["foo", "/lib/foo"]]

    Note that in the OSTree model, not all directories are managed by OSTree. In short, only files in /usr (or UsrMove symlinks into /usr) and /etc are supported. For more details, see the OSTree manual: https://ostree.readthedocs.io/en/latest/manual/deployment/

  • tmp-is-dir: boolean, optional: Defaults to false. By default, rpm-ostree creates symlink /tmpsysroot/tmp. When set to true, /tmp will be a regular directory, which allows the systemd unit tmp.mount to mount it as tmpfs. It's more flexible to leave it as a directory, and further, we don't want to encourage /sysroot to be writable. For host system composes, we recommend turning this on; it's left off by default to ease the transition.

  • machineid-compat: boolean, optional: Defaults to true. By default, rpm-ostree creates /usr/etc/machine-id as an empty file for historical reasons. Set this to false to ensure it's not present at all. This will cause systemd to execute ConditionFirstBoot=, which implies running systemctl preset-all for example. This requires booting the system with rw so that systemd can properly populate /etc/machine-id and execute the presets at switchroot. When this is enabled, the units directive will no longer function. Instead, create a /usr/lib/systemd/system-presets/XX-example.preset file as part of a package or in the postprocess script.

Experimental options

All options listed here are subject to change or removal in a future version of rpm-ostree.

  • rojig: Object, optional. Sub-keys are name, summary, license, and description. Of those, name and license are mandatory.