#!/bin/bash -ex

# Tries to download latest cached node_modules based on package-lock.json
# If it can't, then `npm ci` and push up node_modules to cache

# Assumes S3_BUCKET env var has been set, and that `aws` credentials
# are configured (either in env, or ~/.aws/credentials)

CHECKSUM=$(sha256sum package-lock.json | awk '{print $1}')

if ! aws s3 cp s3://${S3_BUCKET}/cache/${CHECKSUM}.tgz - | tar -xz; then
  npm ci
  tar -cz node_modules | aws s3 cp - s3://${S3_BUCKET}/cache/${CHECKSUM}.tgz
fi