Treefile reference

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:

  • edition: string, optional: If not set, the default value is treated as 2014. The only other supported value is 2024, which changes some defaults.

  • ref: string, mandatory: Holds a string which will be the name of the branch for the content. This field supports variable substitution.

    Example: ref: "cool-os/${releasever}/${stream}"

  • metadata: Mapping of strings to values, optional. This can be used for other tools to insert arbitrary metadata into the treefile which they parse later, for example via rpm-ostree compose tree --print-metadata-json. All (top-level) objects of type string support variable substitution.

  • 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, optional: Names of yum repositories to use, from any files that end in .repo, in the same directory as the treefile. If missing, all yum repos enabled by default are used. 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.

  • ignore-devices: boolean, optional: Defaults to true. If true, then all character and block device files found in the target root (except overlayfs whiteouts, which are automatically “quoted”) will be ignored.

  • ima: boolean, optional: Defaults to false. Propagate any IMA signatures in input RPMs into the final OSTree commit.

  • 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. This is the default for editions 2024 and above.
  • 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. This field supports variable substitution.

    Example: mutate-os-release: "${releasever}"

  • 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: Each entry in this list should name a package; however, virtual provides are also supported. For convenience when writing YAML/JSON, entries in this list will also be split by whitespace. Finally, another syntax special case is that surrounding the entry with single quotes (') as part of the string will suppress this whitespace split, and that in turn makes it possible to use version query syntax (podman >= 4.1).

    Example:

    packages:
      - ca-certificates
      - efitools pesign sbsigntools
      - "'podman >= 4.1'"
      - kernel-6.9.11-100.fc39
    
  • packages-$basearch: Array of strings, optional: Set of installed packages, used only if $basearch matches the target architecture name.

  • exclude-packages: Array of strings, optional: Each entry in this list is a package name which will be filtered out. If a package listed in the manifest (“manifest package”) indirectly hard depends on one of these packages, it will be a fatal error. If a manifest package recommends one of these packages, the recommended package will simply be omitted. It is also a fatal error to include a package both as a manifest package and in the exclusion list.

    An example use case for this is for Fedora CoreOS, which will exclude the python and python3 packages to ensure that nothing included in the OS starts depending on it in the future.

  • repo-packages: Array of objects, optional: Set of packages to install from specific repos. Each object in the array supports the following keys:
    • packages: Array of strings, required: List of packages to install.
    • repo: String, required: Name of the repo from which to fetch packages.
  • 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.

  • container-cmd: array of strings, optional: This maps to the CMD Dockerfile instruction, and is currently only meaningful when encapsulating/exporting an ostree commit as a Docker/OCI container.

  • 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. Deprecated; you should place files in /etc/dracut.conf.d instead. This option is ignored when regenerating the initramfs in the container flow.

  • rpmdb: String, optional: The RPM database backend. Can be one of target (the default) or host. Legacy values bdb, ndb, and sqlite are treated as target. This option is a historical mistake; ultimately the only thing that really works is to write the rpmdb in the target format - the format that the librpm library in the target filesystem tree understands. However, this is a relatively new default, so the value host is provided as a fallback

  • rpmdb-normalize: boolean, optional. Defaults to false. If enabled, this will perform various manipulations of the RPM database to, as much as possible, guarantee a deterministic result for the on-disk RPM database. Requires the SOURCE_DATE_EPOCH environment variable to be set to the UNIX epoch time to be used as the build timestamp. Currently only fully supports the bdb backend. Somewhat experimental.

  • selinux-label-version: integer, optional: When set to 1, this will turn on an ostree flag which labels files in /usr/etc as if they were in /etc. This is important to aid in having a “transient” /etc.

  • cliwrap: boolean, optional. Defaults to false. If enabled, rpm-ostree will replace binaries such as /usr/bin/rpm with wrappers that intercept unsafe operations, or adjust functionality.

    This is deprecated and we now plan to land relevant functionality in the upstream projects.

  • cliwrap-binaries: array of strings, optional. An explicit list of binaries to enable cliwrap. The current allowed set contains just one value: kernel-install.

  • readonly-executables: boolean, optional. Defaults to false (for backcompat). If enabled, rpm-ostree will remove the write bit from all executables.

    The default is false out of conservatism; you likely want to enable this.

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

    Example: releasever: "26" Example: releasever: 35

    When defined, it is automatically also added to the variable map described below. Thus, it can be used for substitutions and conditional includes.

  • 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-prefixversion progression
    2222, 22.1, 22.2, …
    22.122.1.1, 22.1.2, 22.1.3, …
    22.<date:%Y>22.2019.0, 22.2019.1, 22.2020.0, …
    22.<date:%Y>.122.2019.1.0, 22.2019.1.1, 22.2020.1.0, …

    This field supports variable substitution.

    Example: automatic-version-prefix: "22.0" Example: automatic-version-prefix: "${releasever}.<date:%Y%m%d>.dev"

  • automatic-version-suffix: String, optional: This must be a single ASCII character. The default value is .. Used by automatic-version-prefix. For example, if you set this to - then 22 will become 22-1, 22-2 etc.

  • 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. All objects of type string support variable substitution.

    Example:

    add-commit-metadata:
      cool-os.is-production: false
      cool-os.git-snapshot: "${git_snapshot}"
    
  • 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.

    When combined with includes, the order in which these scripts are executed are dictated by the following two rules:

    • postprocess scripts in a manifest are executed after postprocess scripts contained in any included manifests
    • if multiple manifests are included, postprocess scripts in the latter manifests are executed before earlier ones

    For example, given the following manifests:

    # manifest.yaml
    include:
      - manifests/kernel.yaml
      - manifests/bootupd.yaml
    postprocess:
      - echo foo
    
    # manifests/kernel.yaml
    postprocess:
      - echo bar
    
    # manifests/bootupd.yaml
    postprocess:
      - echo baz
    

    Postprocess scripts will be executed in the following order:

    • manifests/bootupd.yaml
    • manifests/kernel.yaml
    • manifest.yaml

    (I.e. it will echo in this order: baz, bar, then foo.)

  • 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.

  • arch-include: object (Map<String,include>), optional: Each member of this object should be the name of a base architecture ($basearch), and the include value functions the same as the include key above - it can be either a single string, or an array of strings - and it has the same semantics. Entries which match arch-include are processed after include.

    Example (in YAML):

    arch-include:
      x86_64: bootloader-x86_64.yaml
      s390x:
        - bootloader-s390x.yaml
        - tweaks-s390x.yaml
    
  • conditional-include: array of objects, optional: This is like include, but supports conditions based on variables defined in variables. The syntax is:

     conditional-include:
       - if: <var> <op> <value>
         include: <include>
    

    <var> is a variable name previously defined via variables. <op> must be one of ==, !=, <, <=, >, >=. <value> has the same sematics as variable values: it can be a boolean, number, or string (in quotes). <include> functions the same as the include key above - it can be either a string or an array of strings.

    Multiple conditions may be provided:

     conditional-include:
       - if:
         - <var> <op> <value>
         - <var> <op> <value>
         - <var> <op> <value>
         include: <include>
    

    In that case, all conditions must be met for the inclusion to happen.

    Example:

    variables:
      devpackages: true
      stream: "development"
    releasever: 35
    conditional-include:
      - if: devpackages == true
        include: dev-packages.yaml
    conditional-include:
      - if: stream != "development"
        include: delete-dev-files.yaml
    conditional-include:
      - if: releasever >= 35
        include: f35-selinux-workaround.yaml
    
  • 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. This also implies several other options, such as tmp-is-dir: true and selinux: false.

  • 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://ostreedev.github.io/ostree/deployment/

  • tmp-is-dir: boolean, optional: Defaults to false in editions < 2024, otherwise true. 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.

  • platform-module: string, optional. For the very rare case where you need to either provide or override the platform module. When using RPM modules libdnf will attempt to derive the appropriate platform module by inspecting various virtual provide entries on the available packages. If this fails it will fall back to parsing /etc/os-release or /usr/lib/os-release in that order. If the first mechanism fails and we are running a compose, we will not have the necessary files to allow the fall back to work. If you find yourself in this situation you can provide the platform module name yourself using this option. You can also use this to override the platform module if needed. This field supports variable substitution.

  • variables: object (Map<String, value>), optional: Define new variables which could then be substituted into the value of various fields and used in conditional includes described above. Supported value types are booleans, numbers, and strings.

    The releasever variable is reserved and automatically populated to the same value as the releasever key. The basearch variable is reserved and automatically populated to the base architecture of the compose.

    Example:

    variables:
      devpackages: true
      stream: "development"
    releasever: 35
    ref: "cool-os/${releasever}/${stream}"
    conditional-include:
      - if: devpackages == true
        include: dev-packages.yaml
    
  • repo_metadata: String, optional: Can be one of inline (the default), detached or disabled. If set to inline, parts of the RPM repository metadata are added to the OSTree commit metadata under the rpmostree.rpmmd-repos key. Setting this to detached also adds the information but puts it in the detached metadata of the commit, preventing it from affecting the commit checksum. Setting it to disabled will prevent the metadata from being added at all.

Experimental options

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

  • lockfile-repos: array of strings, optional: Semantically similar to repo, but these repos will only be used to fetch packages locked via lockfiles. This is useful when locked packages are kept separately from the primary repos and one wants to ensure that rpm-ostree will otherwise not select unlocked packages from them.
  • repovars: object (Map<String, String>), optional: yum repository variable names to use when substituting variables in yum repo files. The releasever variable name is invalid. Use the releasever key instead. The basearch name is invalid; it is filled in automatically.
  • opt-usrlocal: enum, optional: Defaults to var. There are two possible behaviors:
    • var: /opt and /usr/local are symlinks to subdirectories in /var and are purely machine-local state.
    • root: These are plain directories; only use this with composefs enabled!

Kickstarts

A file ending in .ks will be parsed as a kickstart file. Only a small subset of kickstart configuration is honored:

  • %packages (both install and excludes via prefixing with -) The only supported argument is --exclude-weakdeps, which translates to recommends: false. Note that this has a global effect if set.
  • %include (Only child paths from the included file, not absolute paths)

Associated directories

In edition 2024, “associated directories” have been introduced as an experimental feature. These are “drop-in” style directories which can contain inline content or scripts. When processing a manifest file, if these subdirectories exist in the same directory as the manifest, they will be automatically used:

  • finalize.d: Executed synchronously in alphanumeric order from the host/ambient environment (not from the target); the current working directory will be the target root filesystem. There is no additional sandboxing or containerization applied to the execution of the binary. The builtin “change detection” is not applied to the content of the scripts.