cached-bundle

#!/usr/bin/env bash
# Usage: cached-bundle install --deployment
#
# After running `bundle`, caches the `vendor/bundle` directory to S3.
# On the next run, restores the cached directory before running `bundle`.
# When `Gemfile.lock` changes, the cache gets rebuilt.
#
# Requirements:
# - Gemfile.lock
# - REPO_SLUG
# - .ruby-version
# - S3_BUILD_CACHE_BUCKET
# - bundle
# - curl
#
# Author: Mislav Marohnić

set -e

compute_md5() {
  local output="$(openssl md5)"
  echo "${output##* }"
}

download() {
  curl --tcp-nodelay -qsfL "$1" -o "$2"
}

script_dir=$(dirname "${BASH_SOURCE[0]}")
bundle_path="vendor/bundle"
cache_buster="${BUNDLE_GEMFILE:-Gemfile}.lock"
ruby_version=$(cat .ruby-version)
if [ ! -f $cache_buster ]; then
  cache_buster="$GEMSPEC"
fi
cache_busting_hash="$(compute_md5 <"$cache_buster")"

cache_name="bundler-${ruby_version}-${cache_busting_hash}.tgz"
fetch_url="http://${S3_BUILD_CACHE_BUCKET}.s3.amazonaws.com/${REPO_SLUG}/${cache_name}"

if download "$fetch_url" "$cache_name"; then
  echo "Reusing cached bundle ${cache_name}"
  tar xzf "$cache_name"
fi

echo "Running 'bundle $@'..."
bundle "$@"

if [ ! -f "$cache_name" ]; then
  if [ -z "$S3_SECRET_ACCESS_KEY" ] || [ -z "$S3_ACCESS_KEY_ID" ]
  then
    echo "Enviroment variables not set. Exiting..."
    exit 0
  fi

  echo "Caching \`${bundle_path}' to S3"
  tar czf "$cache_name" "$bundle_path"

  curl -s 'https://gist.githubusercontent.com/stefanoverna/9179228/raw/s3-put' | bash /dev/stdin "$cache_name" "${S3_BUILD_CACHE_BUCKET}:${REPO_SLUG}/${cache_name}"
fi

# vim: filetype=sh

s3-put

#!/usr/bin/env bash
# Usage: s3-put <FILE> <S3_BUCKET>[:<PATH>] [<CONTENT_TYPE>]
#
# Uploads a file to the Amazon S3 service.
# Outputs the URL for the newly uploaded file.
#
# Requirements:
# - S3_ACCESS_KEY_ID
# - S3_SECRET_ACCESS_KEY
# - openssl
# - curl
#
# Author: Mislav Marohnić

set -e

authorization() {
  local signature="$(string_to_sign | hmac_sha1 | base64)"
  echo "AWS ${S3_ACCESS_KEY_ID?}:${signature}"
}

hmac_sha1() {
  openssl dgst -binary -sha1 -hmac "${S3_SECRET_ACCESS_KEY?}"
}

base64() {
  openssl enc -base64
}

bin_md5() {
  openssl dgst -binary -md5
}

string_to_sign() {
  echo "$http_method"
  echo "$content_md5"
  echo "$content_type"
  echo "$date"
  echo "x-amz-acl:$acl"
  printf "/$bucket/$remote_path"
}

date_string() {
  LC_TIME=C date "+%a, %d %h %Y %T %z"
}

file="$1"
bucket="${2%%:*}"
remote_path="${2#*:}"
content_type="$3"

if [ -z "$remote_path" ] || [ "$remote_path" = "$bucket" ]; then
  remote_path="${file##*/}"
fi

http_method=PUT
acl="public-read"
content_md5="$(bin_md5 < "$file" | base64)"
date="$(date_string)"

url="https://$bucket.s3.amazonaws.com/$remote_path"

curl -qsSf -T "$file" \
  -H "Authorization: $(authorization)" \
  -H "x-amz-acl: $acl" \
  -H "Date: $date" \
  -H "Content-MD5: $content_md5" \
  -H "Content-Type: $content_type" \
  "$url"

echo "$url"

# vim: filetype=sh