Dockerfile: Use rpmbuild

We were bit before by just doing a `COPY` of our binaries overtop of
the base image because that doens't remove old files.

Replace the pre-build approach with rpmbuild, and then change to
do an rpm-based upgrade so that we fix that problem.

Note that we still preserve incremental rebuilds by overriding
some of the RPM build process.

Assisted-by: Claude Code (Sonnet 4.5)
Signed-off-by: Colin Walters <walters@verbum.org>

Author: cgwalters

.dockerignore

@@ -8,6 +8,9 @@
 # Toplevel build bits
 !Makefile
 !Cargo.*
+# License and doc files needed for RPM
+!LICENSE-*
+!README.md
 # We do build manpages from markdown
 !docs/
 # We use the spec file

Dockerfile

@@ -10,50 +10,37 @@ ARG base=quay.io/centos-bootc/centos-bootc:stream10
 FROM scratch as src
 COPY . /src
 
+# And this image only captures contrib/packaging separately
+# to ensure we have more precise cache hits.
+FROM scratch as packaging
+COPY contrib/packaging /
+
 FROM $base as base
-# We could inject other content here
+# Mark this as a test image (moved from --label build flag to fix layer caching)
+LABEL bootc.testimage="1"
 
 # This image installs build deps, pulls in our source code, and installs updated
 # bootc binaries in /out. The intention is that the target rootfs is extracted from /out
 # back into a final stage (without the build deps etc) below.
-FROM base as build
+FROM base as buildroot
 # Flip this off to disable initramfs code
 ARG initramfs=1
-# This installs our package dependencies, and we want to cache it independently of the rest.
-# Basically we don't want changing a .rs file to blow out the cache of packages. So we only
-# copy files necessary
-COPY contrib/packaging /tmp/packaging
-RUN <<EORUN
-set -xeuo pipefail
-. /usr/lib/os-release
-case $ID in
-  centos|rhel) dnf config-manager --set-enabled crb;;
-  fedora) dnf -y install dnf-utils 'dnf5-command(builddep)';;
-esac
-# Handle version skew, xref https://gitlab.com/redhat/centos-stream/containers/bootc/-/issues/1174
-dnf -y distro-sync ostree{,-libs} systemd
-# Install base build requirements
-dnf -y builddep /tmp/packaging/bootc.spec
-# And extra packages
-grep -Ev -e '^#' /tmp/packaging/fedora-extra.txt | xargs dnf -y install
-rm /tmp/packaging -rf
-EORUN
+# Version for RPM build (optional, computed from git in Justfile)
+ARG pkgversion=
+# This installs our buildroot, and we want to cache it independently of the rest.
+# Basically we don't want changing a .rs file to blow out the cache of packages.
+RUN --mount=type=bind,from=packaging,target=/run/packaging /run/packaging/install-buildroot
 # Now copy the rest of the source
 COPY --from=src /src /src
 WORKDIR /src
 # See https://www.reddit.com/r/rust/comments/126xeyx/exploring_the_problem_of_faster_cargo_docker/
 # We aren't using the full recommendations there, just the simple bits.
 # First we download all of our Rust dependencies
 RUN --mount=type=cache,target=/src/target --mount=type=cache,target=/var/roothome cargo fetch
-# Then on general principle all the stuff from the Makefile runs with no network
-RUN --mount=type=cache,target=/src/target --mount=type=cache,target=/var/roothome --network=none <<EORUN
-set -xeuo pipefail
-make
-make install-all DESTDIR=/out
-if test "${initramfs:-}" = 1; then
-  make install-initramfs-dracut DESTDIR=/out
-fi
-EORUN
+
+FROM buildroot as build
+# Build RPM directly from source, using cached target directory
+RUN --mount=type=cache,target=/src/target --mount=type=cache,target=/var/roothome --network=none RPM_VERSION=${pkgversion} /src/contrib/packaging/build-rpm
 
 # This "build" includes our unit tests
 FROM build as units
@@ -70,76 +57,14 @@ RUN --mount=type=cache,target=/src/target --mount=type=cache,target=/var/roothom
 FROM base
 # See the Justfile for possible variants
 ARG variant
-RUN <<EORUN
-set -xeuo pipefail
-case "${variant}" in
-  *-sdboot)
-    dnf -y install systemd-boot-unsigned
-    # And uninstall bootupd
-    rpm -e bootupd
-    rm /usr/lib/bootupd/updates -rf
-    dnf clean all
-    rm -rf /var/cache /var/lib/{dnf,rhsm} /var/log/*
-  ;;
-esac
-EORUN
+RUN --mount=type=bind,from=packaging,target=/run/packaging /run/packaging/configure-variant "${variant}"
 # Support overriding the rootfs at build time conveniently
 ARG rootfs=
-RUN <<EORUN
-set -xeuo pipefail
-# Do we have an explicit build-time override? Then write it.
-if test -n "$rootfs"; then
-  cat > /usr/lib/bootc/install/80-rootfs-override.toml <<EOF
-[install.filesystem.root]
-type = "$rootfs"
-EOF
-else
-  # Query the default rootfs
-  base_rootfs=$(bootc install print-configuration | jq -r '.filesystem.root.type // ""')
-  # No filesystem override set. If we're doing composefs, we need a FS that
-  # supports fsverity. If btrfs is available we'll pick that, otherwise ext4.
-  fs=
-  case "${variant}" in
-    composefs*)
-      btrfs=$(grep -qEe '^CONFIG_BTRFS_FS' /usr/lib/modules/*/config && echo btrfs || true)
-      fs=${btrfs:-ext4}
-      ;;
-    *)
-      # No explicit filesystem set and we're not using composefs. Default to xfs
-      # with the rationale that we're trying to get filesystem coverage across
-      # all the cases in general.
-      if test -z "${base_rootfs}"; then
-        fs=xfs
-      fi 
-      ;;
-  esac
-  if test -n "$fs"; then
-    cat > /usr/lib/bootc/install/80-ext4-composefs.toml <<EOF
-[install.filesystem.root]
-type = "${fs}"
-EOF
-  fi
-fi
-
-# Ensure we've flushed out prior state (i.e. files no longer shipped from the old version);
-# and yes, we may need to go to building an RPM in this Dockerfile by default.
-(set +x; rpm -ql bootc | while read line; do if test -f $line; then rm -v $line; fi; done)
-EORUN
-# Create a layer that is our new binaries
-COPY --from=build /out/ /
-# We have code in the initramfs so we always need to regenerate it
-RUN --network=none <<EORUN
-set -xeuo pipefail
-if test -x /usr/lib/bootc/initramfs-setup; then
-   kver=$(cd /usr/lib/modules && echo *);
-   env DRACUT_NO_XATTR=1 dracut -vf /usr/lib/modules/$kver/initramfs.img $kver
-fi
-# Only in this containerfile, inject a file which signifies
-# this comes from this development image. This can be used in
-# tests to know we're doing upstream CI.
-touch /usr/lib/.bootc-dev-stamp
-# And test our own linting
-## Workaround for https://github.com/bootc-dev/bootc/issues/1546
-rm -rf /root/buildinfo
-bootc container lint --fatal-warnings
-EORUN
+RUN --mount=type=bind,from=packaging,target=/run/packaging /run/packaging/configure-rootfs "${variant}" "${rootfs}"
+# Install the RPM built in the build stage
+# This replaces the manual file deletion hack and COPY, ensuring proper package management
+# Use rpm -Uvh with --oldpackage to allow replacing with dev version
+COPY --from=build /out/*.rpm /tmp/
+RUN --mount=type=bind,from=packaging,target=/run/packaging --network=none /run/packaging/install-rpm-and-setup /tmp
+# Finally, testour own linting
+RUN bootc container lint --fatal-warnings

Justfile

@@ -36,6 +36,30 @@ build:
     podman build {{base_buildargs}} -t localhost/bootc-bin {{buildargs}} .
     ./tests/build-sealed {{variant}} localhost/bootc-bin localhost/bootc
 
+# Build packages (e.g. RPM) using a container buildroot
+_packagecontainer:
+    #!/bin/bash
+    set -xeuo pipefail
+    # Compute version from git (matching xtask.rs gitrev logic)
+    if VERSION=$(git describe --tags --exact-match 2>/dev/null); then
+        VERSION="${VERSION#v}"
+        VERSION="${VERSION//-/.}"
+    else
+        COMMIT=$(git rev-parse HEAD | cut -c1-10)
+        COMMIT_TS=$(git show -s --format=%ct)
+        TIMESTAMP=$(date -u -d @${COMMIT_TS} +%Y%m%d%H%M)
+        VERSION="${TIMESTAMP}.g${COMMIT}"
+    fi
+    echo "Building RPM with version: ${VERSION}"
+    podman build {{base_buildargs}} {{buildargs}} --build-arg=pkgversion=${VERSION} -t localhost/bootc-pkg --target=build .
+
+# Build a packages (e.g. RPM) into target/
+# Any old packages will be removed.
+package: _packagecontainer
+    mkdir -p target
+    rm -vf target/*.rpm
+    podman run --rm localhost/bootc-pkg tar -C /out/ -cf - . | tar -C target/ -xvf -
+
 # This container image has additional testing content and utilities
 build-integration-test-image: build
     cd hack && podman build {{base_buildargs}} -t localhost/bootc-integration-bin -f Containerfile .

contrib/packaging/bootc.spec

@@ -1,4 +1,5 @@
 %bcond_without check
+%bcond_with tests
 %if 0%{?rhel} >= 9 || 0%{?fedora} > 41
     %bcond_without ostree_ext
 %else
@@ -21,7 +22,8 @@
 %endif
 
 Name:           bootc
-Version:        1.1.5
+# Ensure this local build overrides anything else.
+Version:        99999.0.0
 Release:        1%{?dist}
 Summary:        Bootable container system
 
@@ -84,17 +86,49 @@ Recommends: podman
 %description -n system-reinstall-bootc
 This package provides a utility to simplify reinstalling the current system to a given bootc image.
 
+%if %{with tests}
+%package tests
+Summary: Integration tests for bootc
+Requires: %{name} = %{version}-%{release}
+
+%description tests
+This package contains the integration test suite for bootc.
+%endif
+
 %global system_reinstall_bootc_install_podman_path %{_prefix}/lib/system-reinstall-bootc/install-podman
 
+%if 0%{?container_build}
+# Source is already at /src, no subdirectory
+%global _buildsubdir .
+%endif
+
 %prep
+%if ! 0%{?container_build}
 %autosetup -p1 -a1
 # Default -v vendor config doesn't support non-crates.io deps (i.e. git)
 cp .cargo/vendor-config.toml .
 %cargo_prep -N
 cat vendor-config.toml >> .cargo/config.toml
 rm vendor-config.toml
+%else
+# Container build: source already at _builddir (/src), nothing to extract
+# RPM's %mkbuilddir creates a subdirectory; symlink it back to the source
+cd ..
+rm -rf %{name}-%{version}-build
+ln -s . %{name}-%{version}-build
+cd %{name}-%{version}-build
+%endif
 
 %build
+export SYSTEM_REINSTALL_BOOTC_INSTALL_PODMAN_PATH=%{system_reinstall_bootc_install_podman_path}
+%if 0%{?container_build}
+# Container build: use cargo directly with cached dependencies
+export CARGO_HOME=/var/roothome/.cargo
+cargo build -j%{_smp_build_ncpus} --release %{?with_rhsm:--features rhsm} \
+    --bin=bootc --bin=system-reinstall-bootc \
+    %{?with_tests:--bin tests-integration}
+make manpages
+%else
 # Build the main bootc binary
 %if %new_cargo_macros
     %cargo_build %{?with_rhsm:-f rhsm}
@@ -104,7 +138,6 @@ rm vendor-config.toml
 
 # Build the system reinstallation CLI binary
 %global cargo_args -p system-reinstall-bootc
-export SYSTEM_REINSTALL_BOOTC_INSTALL_PODMAN_PATH=%{system_reinstall_bootc_install_podman_path}
 %if %new_cargo_macros
     # In cargo-rpm-macros, the cargo_build macro does flag processing,
     # so we need to pass '--' to signify that cargo_args is not part
@@ -118,18 +151,24 @@ export SYSTEM_REINSTALL_BOOTC_INSTALL_PODMAN_PATH=%{system_reinstall_bootc_insta
 %endif
 
 make manpages
+%endif
 
+%if ! 0%{?container_build}
 %cargo_vendor_manifest
 # https://pagure.io/fedora-rust/rust-packaging/issue/33
 sed -i -e '/https:\/\//d' cargo-vendor.txt
 %cargo_license_summary
 %{cargo_license} > LICENSE.dependencies
+%endif
 
 %install
 %make_install INSTALL="install -p -c"
 %if %{with ostree_ext}
 make install-ostree-hooks DESTDIR=%{?buildroot}
 %endif
+%if %{with tests}
+install -D -m 0755 target/release/tests-integration %{buildroot}%{_bindir}/bootc-integration-tests
+%endif
 mkdir -p %{buildroot}/%{dirname:%{system_reinstall_bootc_install_podman_path}}
 cat >%{?buildroot}/%{system_reinstall_bootc_install_podman_path} <<EOF
 #!/bin/bash
@@ -153,8 +192,10 @@ fi
 %files -f bootcdoclist.txt
 %license LICENSE-MIT
 %license LICENSE-APACHE
+%if ! 0%{?container_build}
 %license LICENSE.dependencies
 %license cargo-vendor.txt
+%endif
 %doc README.md
 %{_bindir}/bootc
 %{_prefix}/lib/bootc/
@@ -169,5 +210,10 @@ fi
 %{_bindir}/system-reinstall-bootc
 %{system_reinstall_bootc_install_podman_path}
 
+%if %{with tests}
+%files tests
+%{_bindir}/bootc-integration-tests
+%endif
+
 %changelog
 %autochangelog

contrib/packaging/build-rpm

@@ -0,0 +1,44 @@
+#!/bin/bash
+# Build bootc RPM package from source
+set -xeuo pipefail
+
+# Version can be passed via RPM_VERSION env var (set by Dockerfile ARG)
+# or defaults to the hardcoded value in the spec file
+VERSION="${RPM_VERSION:-}"
+
+# Determine output directory (defaults to /out)
+OUTPUT_DIR="${1:-/out}"
+SRC_DIR="${2:-/src}"
+
+if [ -n "${VERSION}" ]; then
+    echo "Building RPM with version: ${VERSION}"
+else
+    echo "Building RPM with version from spec file"
+fi
+
+# Create temporary rpmbuild directories
+mkdir -p /tmp/rpmbuild/{RPMS,BUILDROOT,SPECS}
+
+# If version is provided, create modified spec file; otherwise use original
+if [ -n "${VERSION}" ]; then
+    sed "s/^Version:.*/Version:        ${VERSION}/" \
+        "${SRC_DIR}/contrib/packaging/bootc.spec" > /tmp/rpmbuild/SPECS/bootc.spec
+    SPEC_FILE=/tmp/rpmbuild/SPECS/bootc.spec
+else
+    SPEC_FILE="${SRC_DIR}/contrib/packaging/bootc.spec"
+fi
+
+# Build RPM
+rpmbuild -bb \
+  --define "_topdir /tmp/rpmbuild" \
+  --define "_builddir ${SRC_DIR}" \
+  --define "container_build 1" \
+  --with tests \
+  --nocheck \
+  "${SPEC_FILE}"
+
+# Copy built RPMs to output directory
+ARCH=$(uname -m)
+mkdir -p "${OUTPUT_DIR}"
+cp /tmp/rpmbuild/RPMS/${ARCH}/*.rpm "${OUTPUT_DIR}/"
+rm -rf /tmp/rpmbuild