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>

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

contrib/packaging/configure-rootfs

@@ -0,0 +1,46 @@
+#!/bin/bash
+# Configure rootfs type for bootc installation
+set -xeuo pipefail
+
+VARIANT="${1:-}"
+ROOTFS="${2:-}"
+
+# Support overriding the rootfs at build time
+CONFIG_DIR="/usr/lib/bootc/install"
+mkdir -p "${CONFIG_DIR}"
+
+# Do we have an explicit build-time override? Then write it.
+if [ -n "$ROOTFS" ]; then
+  cat > "${CONFIG_DIR}/80-rootfs-override.toml" <<EOF
+[install.filesystem.root]
+type = "$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 [ -z "${base_rootfs}" ]; then
+        fs=xfs
+      fi
+      ;;
+  esac
+
+  if [ -n "$fs" ]; then
+    cat > "${CONFIG_DIR}/80-ext4-composefs.toml" <<EOF
+[install.filesystem.root]
+type = "${fs}"
+EOF
+  fi
+fi

contrib/packaging/configure-variant

@@ -0,0 +1,26 @@
+#!/bin/bash
+# Configure system for a specific bootc variant
+set -xeuo pipefail
+
+VARIANT="${1:-}"
+
+if [ -z "$VARIANT" ]; then
+  # No variant specified, nothing to do
+  exit 0
+fi
+
+# Handle variant-specific configuration
+case "${VARIANT}" in
+  *-sdboot)
+    # Install systemd-boot and remove bootupd
+    dnf -y install systemd-boot-unsigned
+    # Uninstall bootupd
+    rpm -e bootupd
+    rm -rf /usr/lib/bootupd/updates
+    # Clean up package manager caches
+    dnf clean all
+    rm -rf /var/cache /var/lib/{dnf,rhsm} /var/log/*
+  ;;
+  # Future variants can be added here
+  # For Debian support, this could check package manager type and use apt instead
+esac

contrib/packaging/fedora-extra.txt

@@ -5,3 +5,5 @@ rustfmt
 clippy
 git-core
 jq
+# We now always build a package in the container build
+rpm-build

contrib/packaging/install-buildroot

@@ -0,0 +1,15 @@
+#!/bin/bash
+# Install buildroot requirements for Fedora derivatives
+set -xeuo pipefail
+cd $(dirname $0)
+. /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 bootc.spec
+# And extra packages
+grep -Ev -e '^#' fedora-extra.txt | xargs dnf -y install

contrib/packaging/install-rpm-and-setup

@@ -0,0 +1,24 @@
+#!/bin/bash
+# Install bootc RPM and perform post-installation setup
+set -xeuo pipefail
+
+RPM_DIR="${1:-/tmp}"
+
+# Install the RPM package
+# Use rpm -Uvh with --oldpackage to allow replacing with dev version
+rpm -Uvh --oldpackage "${RPM_DIR}"/*.rpm
+rm -f "${RPM_DIR}"/*.rpm
+
+# Regenerate initramfs if we have initramfs-setup
+if [ -x /usr/lib/bootc/initramfs-setup ]; then
+  kver=$(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
+
+# Workaround for https://github.com/bootc-dev/bootc/issues/1546
+rm -rf /root/buildinfo