vendor_npm.sh

#!/usr/bin/env bash

# Vendor in files from npm based on /third_party/npm/package.json & /third_party/npm/yarn.lock

set -eu -o pipefail
# -e: exits if a command fails
# -u: errors if an variable is referenced before being set
# -o pipefail: causes a pipeline to produce a failure return code if any command errors

# sedi makes `sed -i` work on both OSX & Linux
# See https://stackoverflow.com/questions/2320564/i-need-my-sed-i-command-for-in-place-editing-to-work-with-both-gnu-sed-and-bsd
sedi () {
  case $(uname) in
    Darwin*) sedi=('-i' '') ;;
    *) sedi='-i' ;;
  esac

  sed "${sedi[@]}" "$@"
}

readonly RULES_NODEJS_DIR=$(cd $(dirname "$0")/..; pwd)
readonly THIRD_PARTY_DIR=${RULES_NODEJS_DIR}/third_party

readonly DATE=$(date)

readonly PACKAGE_JSON_SHA256=$(cat ${THIRD_PARTY_DIR}/package.json | openssl dgst -sha256)
readonly YARN_LOCK_SHA256=$(cat ${THIRD_PARTY_DIR}/yarn.lock | openssl dgst -sha256)

# runs and adds command run to CMDS for later user
capture_and_run() {
  CMDS="${CMDS}# "$(echo "$@" | sed "s#${RULES_NODEJS_DIR}/##g")$'\n'
  "$@"
}

# preps for vendoring a package
# args:
# $1 - package name
prep() {
  CMDS=""
  PKG=$1
  SRC_DIR=${THIRD_PARTY_DIR}/node_modules/${PKG}
  DST_DIR=${THIRD_PARTY_DIR}/npm/node_modules/${PKG}
  printf "\n\nVendoring ${PKG} to ${DST_DIR}\n"
  rm -rf ${DST_DIR}
  mkdir -p ${DST_DIR}
}

# runs ncc
# args:
# $1 - entry point
# $2 - (optional) additional args
ncc() {
  echo "- compiling ${PKG} with ncc"
  capture_and_run ${THIRD_PARTY_DIR}/node_modules/.bin/ncc build ${SRC_DIR}/$1 ${2:-} -o ${DST_DIR}
}

# minifies with terser
# args:
# $1 - input file
# $1 - output file
minify() {
  echo "- minifying ${PKG} with terser"
  capture_and_run ${THIRD_PARTY_DIR}/node_modules/.bin/terser --compress --mangle --comments '/(^!|@license|@preserve|Copyright)/' -- ${DST_DIR}/$1 > ${DST_DIR}/$2
}

# copies a file
# args:
# $1 - input & output file
copy() {
  echo "- copy $1"
  capture_and_run cp -f ${SRC_DIR}/$1 ${DST_DIR}
}

# copies a file
# args:
# $1 - input file
# $2 - output file
copy_to() {
  echo "- copy $1 to $2"
  capture_and_run cp -f ${SRC_DIR}/$1 ${DST_DIR}/$2
}

# moves a file
# args:
# $1 - input file
# $2 - output file
rename() {
  echo "- rename $1 to $2"
  capture_and_run mv ${DST_DIR}/$1 ${DST_DIR}/$2
}

# create a BUILD file and adds the common header portions
# args:
# $1 - license file
build_file_header() {
  echo """# Generated by /scripts/vendor_npm.sh
load(\"//internal/js_library:js_library.bzl\", \"js_library\")

package(default_visibility = [\"//visibility:public\"])

licenses([\"notice\"])

# Vendored on ${DATE} from npm with /scripts/vendor_npm.sh
exports_files([\"$1\"])

js_library(
    name = \"$(basename ${PKG})\",
    srcs = glob([\"**/*.js\"]),
    package_name = \"${PKG}\",
)
""" > ${DST_DIR}/BUILD.bazel
}

# adds the common footer to the BUILD file
build_file_footer() {
  echo """# shell commands:
${CMDS}
# package.json (SHA256 ${PACKAGE_JSON_SHA256}):
$(cat ${THIRD_PARTY_DIR}/package.json | awk '{print "# "$0}')

# yarn.lock (SHA256 ${YARN_LOCK_SHA256}):
$(cat ${THIRD_PARTY_DIR}/yarn.lock | awk '{print "# "$0}')
""" >> ${DST_DIR}/BUILD.bazel
}


(
  cd ${THIRD_PARTY_DIR}
  yarn install

  ##############################################################################
  # Vendor browserify
  ##############################################################################
  (
    prep browserify
    ncc bin/cmd.js
    echo "- local mod: revert https://github.com/browserify/browserify/pull/1801"
    capture_and_run sedi 's#parent.id !== self._mdeps.top.id#parent.id#' ${DST_DIR}/index.js
    echo "- local mod: workaround https://github.com/zeit/ncc/issues/461"
    capture_and_run sedi "s#require('process/browser.js')#require('./browser1')#" ${DST_DIR}/main.js
    rename index.js index.debug.js
    minify index.debug.js index.js
    copy LICENSE
    build_file_header LICENSE
    echo """filegroup(
    name = \"package_contents\",
    # don't include index.debug.js to keep release smaller
    srcs = glob([\"**/*.js\"], exclude=[\"index.debug.js\"]) + [
        \"advanced.txt\",
        \"BUILD.bazel\",
        \"LICENSE\",
        \"usage.txt\",
    ],
)
""" >> ${DST_DIR}/BUILD.bazel
    build_file_footer
  )

  ##############################################################################
  # Vendor ieee754
  # (required by browserify)
  ##############################################################################
  (
    prep ieee754
    copy index.js
    copy LICENSE
    build_file_header LICENSE
    echo """filegroup(
    name = \"package_contents\",
    srcs = glob([\"**/*.js\"]) + [
        \"BUILD.bazel\",
        \"LICENSE\",
    ],
)
""" >> ${DST_DIR}/BUILD.bazel
    build_file_footer
  )

  ##############################################################################
  # Vendor base64-js
  # (required by browserify)
  ##############################################################################
  (
    prep base64-js
    copy index.js
    copy LICENSE
    build_file_header LICENSE
    echo """filegroup(
    name = \"package_contents\",
    srcs = glob([\"**/*.js\"]) + [
        \"BUILD.bazel\",
        \"LICENSE\",
    ],
)
""" >> ${DST_DIR}/BUILD.bazel
    build_file_footer
  )

  ##############################################################################
  # Vendor @babel/core
  ##############################################################################
  (
    prep @babel/core
    ncc lib/index.js
    rename index.js index.debug.js
    minify index.debug.js index.js
    copy LICENSE
    build_file_header LICENSE
    echo """filegroup(
    name = \"package_contents\",
    # don't include index.debug.js to keep release smaller
    srcs = glob([\"**/*.js\"], exclude=[\"index.debug.js\"]) + [
        \"BUILD.bazel\",
        \"LICENSE\",
    ],
)
""" >> ${DST_DIR}/BUILD.bazel
    build_file_footer
  )

  ##############################################################################
  # Vendor babelify
  ##############################################################################
  (
    prep babelify
    copy index.js
    copy LICENSE
    build_file_header LICENSE
    echo """filegroup(
    name = \"package_contents\",
    srcs = glob([\"**/*.js\"]) + [
        \"BUILD.bazel\",
        \"LICENSE\",
    ],
)
""" >> ${DST_DIR}/BUILD.bazel
    build_file_footer
  )

  ##############################################################################
  # Vendor named-amd
  ##############################################################################
  (
    prep named-amd
    copy_to named-amd.js index.js
    copy LICENSE.md
    build_file_header LICENSE.md
    echo """filegroup(
    name = \"package_contents\",
    srcs = glob([\"**/*.js\"]) + [
        \"BUILD.bazel\",
        \"LICENSE.md\",
    ],
)
""" >> ${DST_DIR}/BUILD.bazel
    build_file_footer
  )

  ##############################################################################
  # Vendor babelify plugins
  ##############################################################################
  readonly BROWSERIFY_PLUGINS=(
    '@babel/plugin-transform-modules-commonjs'
  )
  for PLUGIN in "${BROWSERIFY_PLUGINS[@]}"; do
    (
      prep ${PLUGIN}
      ncc lib/index.js "-e @babel/core"
      echo "- copy babel LICENSE"
      capture_and_run cp -f ${THIRD_PARTY_DIR}/node_modules/@babel/core/LICENSE ${DST_DIR}
      build_file_header LICENSE
      echo """filegroup(
    name = \"package_contents\",
    srcs = glob([\"**/*.js\"]) + [
        \"BUILD.bazel\",
        \"LICENSE\",
    ],
)
""" >> ${DST_DIR}/BUILD.bazel
      build_file_footer
    )
  done

  rm -rf node_modules
)