cache.sh

#!/bin/bash -e
#
# Caching to persistence volume for self hosted ghar

[[ $DEBUG ]] && set -x
export PZSTD_NUM_THREADS=${PZSTD_NUM_THREADS:-"$(nproc)"}

[[ -z "${1}" ]] && echo "KEY is not set (arg 1)" >&2 && exit 2
[[ -z "${2}" ]] && echo "FROM is not set (arg 2)" >&2 && exit 2
[[ -z "${3}" ]] && echo "TO is not set (arg 3)" >&2 && exit 2
key="${1}"
src="${2}"
src="${src%\/}"
des="${3}"
des="${des%\/}"

function setCache() {
  echo "Checking exising cache..."
  hit="$(find "${des}/" -maxdepth 1 -type f -name "${key}*" | head -n1 | xargs)"
  if [[ "${hit}" ]]; then
    echo "Cache hit for key: ${key}, not saving cache"
  else
    echo "Cache miss, Saving cache for key: ${key}"
    time tar --use-compress-program=pzstd -cf "${des}/${key}.tar.zst" "${src}"
    echo "Cache saved successfully"
    echo "Cache saved from key: ${key}"
  fi
}

function getCache() {
  echo "Checking cache..."
  hit="$(find "${des}/" -maxdepth 1 -type f -name "${key}*" | head -n1 | xargs)"
  if [[ "${hit}" ]]; then
    echo "Cache hit for key: ${key}, restoring..."
    time tar --use-compress-program=pzstd -xf "${des}/${key}.tar.zst"
    echo "Cache restored successfully"
    echo "Cache restored from key: ${key}"
  else
    echo "Cache miss, Save cache for key: ${key} on post-cache step"
  fi
}

main() {
  mkdir -p "${des}/"
  if [[ "${MODE}" ]]; then setCache; else getCache; fi
}

main