cas.sh

#!/bin/sh

STORE_PATH="${CAS_STORE_PATH:-.state}"
mkdir -p "${STORE_PATH}"

now=$(date "+%s")
current_hash=$(echo "$@" | xargs -n 1 | LC_ALL=C sort | xargs sha256sum | sha256sum | cut -d" " -f 1)

key="${current_hash}.sha256"
state_path="${STORE_PATH}/${key}"

if [ -f "${CAS_REMOTE}" ]; then
  ${CAS_REMOTE} fetch-state "${key}" "${state_path}"
fi

if [ -f "${state_path}" ]; then
  # this hash is in the state store, re-apply it's date to the state file (as something like s3
  # sync might have changed the file's modified date.
  last_date=$(sed -n 's/date:\s*\(.*\)/\1/p' "${state_path}")
  touch -d "@${last_date}" "${state_path}"

  if [ -f "${CAS_REMOTE}" ]; then
    artifacts=$(sed -n 's/artifact:\s*\(.*\)/\1/p' "${state_path}")

    if [ -n "${artifacts}" ]; then
      echo "${artifacts}" | xargs "${CAS_REMOTE}" fetch-artifacts "${key}"
      echo "${artifacts}" | xargs touch -d "@${last_date}"
    fi
  fi

else
  # this is a new hash
  echo "date: $now" > "${state_path}"

  if [ -f "${CAS_REMOTE}" ]; then
    ${CAS_REMOTE} store-state "${key}" "${state_path}"
  fi
fi

echo "${state_path}"