Rename tier-0 -> base

Part of dropping the "tier" nomenclature which never made sense
since the introduction of `tier-x` anyways.

Signed-off-by: Colin Walters <walters@verbum.org>

Containerfile.base

@@ -12,8 +12,6 @@ FROM quay.io/fedora/fedora:rawhide as repos
 # BOOTSTRAPPING: This can be any image that has rpm-ostree and selinux-policy-targeted.
 FROM quay.io/fedora/fedora:rawhide as builder
 RUN dnf -y install rpm-ostree selinux-policy-targeted
-# Change the input manifest if desired, but this is discouraged.
-ARG MANIFEST=fedora-tier-0.yaml
 # Copy in our source code.
 COPY . /src
 WORKDIR /src
@@ -27,9 +25,9 @@ for x in etc/dnf etc/yum.repos.d etc/pki/rpm-gpg; do
   rm -rf /"$x" && cp -a /repos/${x} /$x
 done
 # And copy to the workdir; TODO fix this in rpm-ostree
-cp /etc/yum.repos.d/*.repo .
+cp /etc/yum.repos.d/*.repo base
 rpm-ostree compose image --image-config fedora-bootc-config.json \
-    --cachedir=/workdir --format=ociarchive --initialize ${MANIFEST} \
+    --cachedir=/workdir --format=ociarchive --initialize base/manifest.yaml \
     --source-root=/repos /buildcontext/out.ociarchive
 EORUN
 

README.md

@@ -58,12 +58,10 @@ It is planned to rework and improve this in the future, especially
 to support smaller custom images. For more on this, see
 [this tracker issue](https://gitlab.com/fedora/bootc/tracker/-/issues/32).
 
+- **base**: A base image with the effective equivalent of installing `bootc kernel systemd dnf`
+  with "recommends" off. Intended as a derivation starting point for minimal systems.
 - **tier-1**: This image is the default, what is published as
   https://quay.io/repository/fedora/fedora-bootc
-- **tier-0**: This content set is more of a convenient centralization point for CI
-  and curation around a package set that we can all agree is the rough minimum
-  necessary for a usable system. It's not meant to be used as is, but layered
-  upon.
 - **packages-recommended.txt**: This content set is the shared base used by all image-based
   Fedora variants (IoT, Atomic Desktops, and CoreOS).
   Changes to this tier may be done without accounting for external users.

base/manifest.yaml

@@ -24,14 +24,15 @@ include:
   - kernel-install.yaml
 
 packages:
+  # This can be replaced later
+  - kernel
   # this is implied by dependencies but let's make it explicit
   - coreutils
   # We need dnf for building derived container images. In Fedora, this pulls
   # in dnf5. In CentOS/RHEL, this pulls in dnf(4). We can simplify this back to
   # just `dnf` once the `dnf` package is retired from Fedora.
   - /usr/bin/dnf
-  # Even in tier-0, we have this.  If you don't want SELinux today, you'll need
-  # to build a custom image.
+  # If you don't want SELinux today, you'll need to build a custom image.
   - selinux-policy-targeted
   # And we want container-selinux because trying to layer it on later currently causes issues.
   - container-selinux

fedora-tier-0.yaml

@@ -1,8 +0,0 @@
-metadata:
-  name: fedora-boot-tier0
-  summary: Fedora Bootable Tier 0
-
-include:
-  - fedora-generic.yaml
-  - tier-0/manifest.yaml
-  - tier-0/kernel.yaml