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3.6. Image Builder blueprint format

Image Builder blueprints are presented to the user as plain text in the Tom’s Obvious, Minimal Language (TOML) format.

The elements of a typical blueprint file include:

The blueprint metadata
name = "BLUEPRINT-NAME"
description = "LONG FORM DESCRIPTION TEXT"
version = "VERSION"

Replace BLUEPRINT-NAME and LONG FORM DESCRIPTION TEXT with a name and description for your blueprint.

Replace VERSION with a version number according to the Semantic Versioning scheme.

This part is present only once for the whole blueprint file.

The entry modules describe the package names and matching version glob to be installed into the image.

The entry group describes a group of packages to be installed into the image. Groups categorize their packages in:

  • Mandatory
  • Default
  • Optional

    Blueprints installs the mandatory packages. There is no mechanism for selecting optional packages.

Groups to include in the image
[[groups]]
name = "group-name"

Replace group-name with the name of the group, such as anaconda-tools, widget, wheel or users.

Packages to include in the image
[[packages]]
name = "package-name"
version = "package-version"

Replace package-name with the name of the package, such as httpd, gdb-doc, or coreutils.

Replace package-version with a version to use. This field supports dnf version specifications:

  • For a specific version, use the exact version number such as 8.30.
  • For latest available version, use the asterisk *.
  • For a latest minor version, use format such as 8.*.

Repeat this block for every package to include.