Extract all layers of a Docker image as files

doxtrak.sh

#!/bin/sh

if [ $# -eq 0 ]
  then
    echo "Usage: doxtrak [docker image name]"
    exit
fi

echo "Extracting..."

mkdir -p $1 && \
    pushd $1 > /dev/null && \
    docker save $1 | tar x  && \
    cat manifest.json \
        | jq -r '.[0].Layers | to_entries[] | [.key, .value] | @csv' \
        | tr ',' ' ' \
        | sed -E 's/^([0-9][0-9]*) \"(.*)\/layer.tar"/mkdir -p \1-\2 \&\& tar xf \"\2\/layer.tar" -C \1-\2 \&\& rm -rf \2;/' \
        | sh

rm repositories *.json && popd > /dev/null