compile

#!/usr/bin/env bash

set -e            # fail fast
set -o pipefail   # don't ignore exit codes when piping output
# set -x          # enable debugging

# Configure directories
build_dir=$1
cache_dir=$2
env_dir=$3

bp_dir=$(cd $(dirname $0); cd ..; pwd)

# Load some convenience functions like status(), echo(), and indent()
source $bp_dir/bin/common.sh

# Output npm debug info on error
trap cat_npm_debug_log ERR

# Look in package.json's engines.node field for a semver range
package_json=$build_dir/back/package.json
semver_range=$(cat $package_json | $bp_dir/vendor/jq -r .engines.node)

# Resolve node version using semver.io
node_version=$(curl --silent --get --data-urlencode "range=${semver_range}" https://semver.io/node/resolve)

# Recommend using semver ranges in a safe manner
if [ "$semver_range" == "null" ]; then
  protip "Specify a node version in package.json"
  semver_range=""
elif [ "$semver_range" == "*" ]; then
  protip "Avoid using semver ranges like '*' in engines.node"
elif [ ${semver_range:0:1} == ">" ]; then
  protip "Avoid using semver ranges starting with '>' in engines.node"
fi

# Output info about requested range and resolved node version
if [ "$semver_range" == "" ]; then
  status "Defaulting to latest stable node: $node_version"
else
  status "Requested node range:  $semver_range"
  status "Resolved node version: $node_version"
fi

# Download node from Heroku's S3 mirror of nodejs.org/dist
status "Downloading and installing node"
node_url="http://s3pository.heroku.com/node/v$node_version/node-v$node_version-linux-x64.tar.gz"
curl $node_url -s -o - | tar xzf - -C $build_dir

# Move node (and npm) into ./vendor and make them executable
mkdir -p $build_dir/vendor
mv $build_dir/node-v$node_version-linux-x64 $build_dir/vendor/node
chmod +x $build_dir/vendor/node/bin/*
PATH=$build_dir/vendor/node/bin:$PATH

# Run node/npm commands from the back dir in build path
cd $build_dir/back

# If node_modules directory is checked into source control then
# rebuild any native deps. Otherwise, restore from the build cache.
if test -d $build_dir/back/node_modules; then
  status "Found existing node_modules directory; skipping cache"
  status "Rebuilding any native dependencies"
  npm rebuild 2>&1 | indent
elif test -d $cache_dir/synth/node_modules; then
  status "Restoring node_modules directory from cache"
  cp -r $cache_dir/synth/node_modules $build_dir/back/

  status "Pruning cached dependencies not specified in package.json"
  npm prune 2>&1 | indent

  if test -f $cache_dir/synth/.heroku/node-version && [ $(cat $cache_dir/synth/.heroku/node-version) != "$node_version" ]; then
    status "Node version changed since last build; rebuilding dependencies"
    npm rebuild 2>&1 | indent
  fi
fi

# Run bower commands from front dir in build path
cd $build_dir/front

# If node_modules directory is checked into source control then
# rebuild any native deps. Otherwise, restore from the build cache.
if test -d $build_dir/front/bower_components; then
  status "Found existing bower_components directory; skipping cache"
elif test -d $cache_dir/synth/bower_components; then
  status "Restoring bower_components directory from cache"
  cp -r $cache_dir/synth/bower_components $build_dir/front/

  # TODO: Prune extraneous bower components; https://github.com/bower/bower/issues/463
fi

# Scope config var availability only to 3rd-party package installation
(
  if [ -d "$env_dir" ]; then
    status "Exporting config vars to environment"
    export_env_dir $env_dir
  fi

  status "Installing back-end dependencies using npm"
  # Make npm output to STDOUT instead of its default STDERR
  cd $build_dir/back
  npm install --userconfig $build_dir/back/.npmrc --production 2>&1 | indent

  status "Installing bower"
  npm install -g bower | indent

  status "Installing front-end dependencies using bower"
  cd $build_dir/front
  bower install -F -p
)

# Persist goodies like node-version in the slug
mkdir -p $build_dir/.heroku

# Save resolved node version in the slug for later reference
echo $node_version > $build_dir/.heroku/node-version

# Purge node-related cached content, being careful not to purge the top-level
# cache, for the sake of heroku-buildpack-multi apps.
rm -rf $cache_dir/synth
mkdir -p $cache_dir/synth

# If app has a node_modules directory, cache it.
if test -d $build_dir/back/node_modules; then
  status "Caching node_modules directory for future builds"
  cp -r $build_dir/back/node_modules $cache_dir/synth
fi

# If app has a bower_components directory, cache it.
if test -d $build_dir/front/bower_components; then
  status "Caching bower_components directory for future builds"
  cp -r $build_dir/front/bower_components $cache_dir/synth
fi

# Copy goodies to the cache
cp -r $build_dir/.heroku $cache_dir/synth

status "Cleaning up node-gyp and npm artifacts"
rm -rf "$build_dir/.node-gyp"
rm -rf "$build_dir/.npm"

# If Procfile is absent, try to create one using `npm start`
if [ ! -e $build_dir/Procfile ]; then
  npm_start=$(cat $build_dir/back/package.json | $bp_dir/vendor/jq -r .scripts.start)

  # If `scripts.start` is set in package.json, or a server.js file
  # is present in the app root, then create a default Procfile
  if [ "$npm_start" != "null" ]; then
    status "No Procfile found; Adding npm start to new Procfile"
    echo "web: npm start" > $build_dir/Procfile
  else
    status "Procfile not found and npm start script is undefined; Add synth server to Procfile"
    echo "web: ./back/node_modules/.bin/synth prod" > $build_dir/Procfile
  fi
fi

# Update the PATH
status "Building runtime environment"
mkdir -p $build_dir/.profile.d
echo "export PATH=\"\$HOME/vendor/node/bin:\$HOME/bin:\$HOME/node_modules/.bin:\$PATH\";" > $build_dir/.profile.d/nodejs.sh

# Post package.json to nomnom service
# Use a subshell so failures won't break the build.
(
  curl \
    --data @$build_dir/package.json \
    --fail \
    --silent \
    --request POST \
    --header "content-type: application/json" \
    https://nomnom.heroku.com/?request_id=$REQUEST_ID \
    > /dev/null
) &