Alpine, Arch Linux, Fedora, RHEL, NixOS Root on ZFS guide: add CI/CD tests

Remove unmaintained Arch Linux guides.

Signed-off-by: Maurice Zhou <yuchen@apvc.uk>

scripts/zfs_root_guide_test.sh

@@ -0,0 +1,105 @@
+#!/usr/bin/env bash
+# working directory: root of repo
+set -vxuef
+
+distro="${1}"
+
+# clean up previous tests
+find /dev/mapper/ -name '*-part4' -print0 \
+     | xargs -t -0I'{}' sh -vxc "swapoff '{}' && cryptsetup close '{}'"
+
+find . -mindepth 1 -maxdepth 1 -type d -name 'rootfs-*' \
+    | while read -r dir; do
+    grep "$(pwd || true)/${dir##./}" /proc/mounts \
+        | cut -f2 -d' ' | sort | tac \
+        | xargs -t -I '{}' sh -vxc "if test -d '{}'; then umount -Rl '{}'; fi"
+done
+find /dev -mindepth 1 -maxdepth 1 -type l -name 'loop*' -exec rm {} +
+zpool export -a
+losetup --detach-all
+
+# download alpine linux chroot
+# it is easier to install rhel with Alpine Linux live media
+# which has native zfs support
+if ! test -f rootfs.tar.gz; then
+    curl --fail-early --fail -Lo rootfs.tar.gz https://dl-cdn.alpinelinux.org/alpine/v3.17/releases/x86_64/alpine-minirootfs-3.17.3-x86_64.tar.gz
+    curl --fail-early --fail -Lo rootfs.tar.gz.sig https://dl-cdn.alpinelinux.org/alpine/v3.17/releases/x86_64/alpine-minirootfs-3.17.3-x86_64.tar.gz.asc
+    gpg --auto-key-retrieve --keyserver hkps://keyserver.ubuntu.com --verify rootfs.tar.gz.sig
+fi
+mkdir rootfs-"${distro}"
+tar --auto-compress --extract --file rootfs.tar.gz --directory ./rootfs-"${distro}"
+
+# Create empty disk image
+qemu-img create -f raw "${distro}"_disk1.img 16G
+qemu-img create -f raw "${distro}"_disk2.img 16G
+losetup --partscan "$(losetup -f || true)"  "${distro}"_disk1.img
+losetup --partscan "$(losetup -f || true)" "${distro}"_disk2.img
+
+run_test () {
+    local path="${1}"
+    local distro="${2}"
+    sed 's|.. ifconfig:: zfs_root_test|::|g' \
+	"${path}" > "${distro}".rst
+    sed -i '/highlight:: sh/d' "${distro}".rst
+
+    # Generate installation script from documentation
+    python scripts/zfs_root_gen_bash.py "${distro}".rst "${distro}".sh
+
+    # Postprocess script for bash
+    sed -i 's|^ *::||g' "${distro}".sh
+    # ensure heredocs work
+    sed -i 's|^ *ZFS_ROOT_GUIDE_TEST|ZFS_ROOT_GUIDE_TEST|g' "${distro}".sh
+    sed -i 's|^ *ZFS_ROOT_NESTED_CHROOT|ZFS_ROOT_NESTED_CHROOT|g' "${distro}".sh
+    sed -i 's|^ *EOF|EOF|g' "${distro}".sh
+
+    # check whether nixos.sh have syntax errors
+    sh -n "${distro}".sh
+
+    ## !shellcheck does not handle nested chroots
+    # create another file with <<EOF construct removed
+    sed 's|<<.*||g' "${distro}".sh > "${distro}"-shellcheck.sh
+    shellcheck \
+        --check-sourced \
+        --enable=all \
+        --shell=dash \
+        --severity=style \
+        --format=tty \
+        "${distro}"-shellcheck.sh
+
+    # Make the installation script executable and run
+    chmod a+x "${distro}".sh
+    ./"${distro}".sh "${distro}"
+}
+
+
+case "${distro}" in
+    ("nixos")
+        run_test 'docs/Getting Started/NixOS/Root on ZFS.rst'  "${distro}"
+        ;;
+
+    ("rhel")
+        run_test 'docs/Getting Started/RHEL-based distro/Root on ZFS.rst'  "${distro}"
+        ;;
+    ("alpine")
+        run_test 'docs/Getting Started/Alpine Linux/Root on ZFS.rst'  "${distro}"
+        ;;
+
+    ("archlinux")
+        run_test 'docs/Getting Started/Arch Linux/Root on ZFS.rst' "${distro}"
+        ;;
+
+    ("fedora")
+        run_test 'docs/Getting Started/Fedora/Root on ZFS.rst' "${distro}"
+        ;;
+
+    ("maintenance")
+        grep -B1000 'MAINTENANCE SCRIPT ENTRY POINT' 'docs/Getting Started/Alpine Linux/Root on ZFS.rst' > test_maintenance.rst
+        cat 'docs/Getting Started/zfs_root_maintenance.rst' >> test_maintenance.rst
+        grep -A1000 'MAINTENANCE SCRIPT ENTRY POINT' 'docs/Getting Started/Alpine Linux/Root on ZFS.rst' >> test_maintenance.rst
+        run_test './test_maintenance.rst' "${distro}"
+        ;;
+    (*)
+        echo "no distro specified"
+        exit 1
+        ;;
+esac