runvm-osbuild

#!/bin/bash
set -eux -o pipefail

usage() {
    cat <<EOC
${0} creates a supermin virtual machine that then
runs OSBuild to build a CoreOS style disk image.

Options:
    --config: JSON-formatted image.yaml
    --help: show this help
    --mpp: the path to the OSBuild mpp.yaml file
    --filepath: where to write the created image file

You probably don't want to run this script by hand. This script is
run as part of 'coreos-assembler build'.
EOC
}

# Parse the passed config JSON and extract a mandatory value
getconfig() {
    k=$1
    jq -re .\""$k"\" < "${config}"
}
# Return a configuration value, or default if not set
getconfig_def() {
    k=$1
    shift
    default=$1
    shift
    jq -re .\""$k"\"//\""${default}"\" < "${config}"
}

while [ $# -gt 0 ];
do
    flag="${1}"; shift;
    case "${flag}" in
        --config)                  config="${1}"; shift;;
        --help)                    usage; exit;;
        --mpp)                     mppyaml="${1}"; shift;;
        --filepath)                filepath="${1}"; shift;;
         *) echo "${flag} is not understood."; usage; exit 10;;
     esac;
done

# Get the base filename of the desired file output path
filename=$(basename "$filepath")

ostree_repo=$(getconfig_def "ostree-repo" "")
ostree_ref=$(getconfig_def "ostree-ref" "")
osname=$(getconfig "osname")
platform=$(getconfig "image-type")
deploy_via_container=$(getconfig_def "deploy-via-container" "")
metal_image_size_mb=$(getconfig "metal-image-size")
cloud_image_size_mb=$(getconfig "cloud-image-size")
container_imgref=$(getconfig "container-imgref")

# If we are deploying via container let's go ahead and pull
# the oci archive path from the config
ostree_container=""
if [ -n "${deploy_via_container}" ]; then
    ostree_container=$(getconfig "ostree-container")
fi

# Since it doesn't exist create loop-control
[ ! -e /dev/loop-control ] && mknod /dev/loop-control c 10 237

# Put the store and the output dir on the cache. At the end we'll mv
# out the created artifact from the output dir to the place it's supposed
# to go.
outdir=cache/osbuild/out
storedir=cache/osbuild/store

processed_json=$(mktemp -t osbuild-XXXX.json)

# Run through the preprocessor
# Note: don't quote the size arguements since they are numbers, not strings
osbuild-mpp                                             \
    -D ref=\""${ostree_ref}"\"                          \
    -D repourl=\""file://${ostree_repo}"\"              \
    -D filename=\""${filename}"\"                       \
    -D ociarchive=\""${ostree_container}"\"             \
    -D osname=\""${osname}"\"                           \
    -D container_imgref=\""${container_imgref}"\"       \
    -D metal_image_size_mb="${metal_image_size_mb}"     \
    -D cloud_image_size_mb="${cloud_image_size_mb}"     \
    "${mppyaml}" "${processed_json}"

# Build the image
osbuild \
    --out "$outdir"              \
    --store "$storedir"          \
    --cache-max-size 9GiB        \
    --checkpoint tree            \
    --checkpoint raw-image       \
    --export "$platform" "${processed_json}"


# Copy it out to the specified location. Use mv here so we remove it
# from the cache qcow2 so we don't cache it.
mv "${outdir}/${platform}/${filename}" "${filepath}"

rm -f "${processed_json}"