chore: use experimental build-chunked-oci

.github/workflows/build.yml

@@ -81,6 +81,7 @@ jobs:
 
       - name: Rechunk
         id: rechunk
+        if: false
         uses: rsturla/eternal-main/.github/actions/rechunk@main
         with:
           builder: ${{ steps.build.outputs.builder }}
@@ -175,6 +176,7 @@ jobs:
 
       - name: Rechunk
         id: rechunk
+        if: false
         uses: rsturla/eternal-main/.github/actions/rechunk@main
         with:
           builder: ${{ steps.build.outputs.builder }}

lumina/Containerfile

@@ -4,7 +4,7 @@ ARG BASE_TAG=41
 ARG FEDORA_VERSION=${BASE_TAG}
 
 
-FROM ${BASE_REGISTRY}:${BASE_TAG}
+FROM ${BASE_REGISTRY}:${BASE_TAG} AS rootfs
 
 ARG FEDORA_VERSION
 ARG BASE_IMAGE
@@ -15,3 +15,22 @@ COPY scripts/ /tmp/scripts/
 RUN chmod +x /tmp/scripts/*.sh /tmp/scripts/*.sh /tmp/scripts/_${BASE_IMAGE}/*.sh && \
   /tmp/scripts/setup.sh && \
   /tmp/scripts/cleanup.sh
+
+# This builder image can be anything as long as it has a new enough
+# rpm-ostree.
+FROM quay.io/fedora/fedora-bootc:rawhide AS builder
+RUN --mount=type=bind,rw=true,src=.,dst=/buildcontext,bind-propagation=shared \
+    --mount=from=rootfs,dst=/rootfs \
+    rm -rf /buildcontext/out.oci && \
+    rpm-ostree experimental compose build-chunked-oci --bootc --format-version=1 \
+           --rootfs=/rootfs --output /buildcontext/out.oci
+
+# Finally, output the OCI archive back into our final container image. Here we
+# can add labels and other metadata - note that no metadata was inherited from
+# the source image - only the root filesystem!
+FROM oci:./out.oci
+# Need to reference builder here to force ordering. But since we have to run
+# something anyway, we might as well cleanup after ourselves.
+RUN --mount=type=bind,from=builder,src=.,target=/var/tmp \
+    --mount=type=bind,rw=true,src=.,dst=/buildcontext,bind-propagation=shared \
+    rm -rf /buildcontext/out.oci