Add metrics plugin + unit tests (#553)

* Add metrics plugin + unit tests

This merges in the build changes and plugin from https://github.com/heroku/heroku-nodejs-metrics-buildpack which installs the metrics plugin https://github.com/heroku/heroku-nodejs-plugin at runtime once a Heroku use opts in to the language metrics feature

CHANGELOG.md

@@ -2,6 +2,8 @@
 
 ## Master
 
+- Add plugin for [Node.js Language Metrics](https://devcenter.heroku.com/articles/language-runtime-metrics-nodejs)
+
 ## v121 (2018-03-02)
 
 - Skip pruning if `NPM_CONFIG_PRODUCTION` or `YARN_PRODUCTION` is defined (#529)

bin/compile

@@ -31,6 +31,7 @@ source $BP_DIR/lib/environment.sh
 source $BP_DIR/lib/binaries.sh
 source $BP_DIR/lib/cache.sh
 source $BP_DIR/lib/dependencies.sh
+source $BP_DIR/lib/plugin.sh
 
 export PATH="$BUILD_DIR/.heroku/node/bin:$BUILD_DIR/.heroku/yarn/bin":$PATH
 
@@ -230,6 +231,8 @@ summarize_build() {
   mmeasure 'modules.size' "$(measure_size)"
 }
 
+install_plugin $BP_DIR $BUILD_DIR
+
 header "Build succeeded!"
 mcount "compile"
 summarize_build | output "$LOG_FILE"

lib/plugin.sh

+
+get_node_major_version() {
+  local node_version="$(node --version)"
+  # major_string will be ex: "6." "8." "10"
+  local major_string=${node_version:1:2}
+  # strip any "."s from major_string
+  local major=${major_string//.}
+  echo $major
+}
+
+install_plugin() {
+  local bp_dir="$1"
+  local build_dir="$2"
+  local major=$(get_node_major_version)
+  local plugin="${bp_dir}/plugin/heroku-nodejs-plugin-node-${major}.tar.gz"
+
+  # If we have a version of the plugin compiled for this version of node, and the
+  # user has not opted out of including the plugin, copy it into the slug.
+  # It will be included at runtime once the user opts into the Node metrics feature
+  if [[ -f "${plugin}" ]] && [[ -z "$HEROKU_SKIP_NODE_PLUGIN" ]]; then
+    mkdir -p "${build_dir}/.heroku/"
+    tar -xzf ${plugin} -C "${build_dir}/.heroku/"
+  fi
+}

plugin/download.sh

+#!/usr/bin/env bash
+# download.sh <tag-name>
+
+set -o errexit    # always exit on error
+set -o pipefail   # don't ignore exit codes when piping output
+
+TAG_NAME=${1:-}
+PLUGIN_DIR=$(dirname $0)
+
+handle_failure() {
+    echo "Failure running script."
+
+    
+    echo "This may be rate-limiting from Github if you've run this script a few times. Here is the rate limit response:"
+    curl "https://api.github.com/rate_limit"
+}
+
+get_latest_release() {
+    # Get latest release tag from GitHub api
+    curl --silent --write-out "%{http_code}" "https://api.github.com/repos/heroku/heroku-nodejs-plugin/releases/latest" | 
+        grep '"tag_name":' | 
+        sed -E 's/.*"([^"]+)".*/\1/'                                    
+}
+
+download() {
+    local url=${1}
+    local file=${2}
+    local code=$(curl "$url" -L --fail --retry 5 --retry-max-time 15 -o "${file}" --write-out "%{http_code}")
+    if [[ "$code" != "200" ]]; then
+        echo "Unable to download from url: $url http code: $code"
+        exit 1
+    fi
+}
+
+delete_old_plugin() {
+    local dir=${1}
+    rm -f "$dir/heroku-nodejs-plugin-node-10.sha512"
+    rm -f "$dir/heroku-nodejs-plugin-node-10.tar.gz"
+    rm -f "$dir/heroku-nodejs-plugin-node-8.sha512"
+    rm -f "$dir/heroku-nodejs-plugin-node-8.tar.gz"
+    rm -f "$dir/heroku-nodejs-plugin-node-9.sha512"
+    rm -f "$dir/heroku-nodejs-plugin-node-9.tar.gz"
+    rm -f "$dir/version"
+}
+
+download_assets_for_release() {
+    local tag=${1}
+    local dir=${2}
+
+    # Node 8
+    download "https://github.com/heroku/heroku-nodejs-plugin/releases/download/$tag/heroku-nodejs-plugin-node-8-$tag.sha512" "$dir/heroku-nodejs-plugin-node-8.sha512"
+    download "https://github.com/heroku/heroku-nodejs-plugin/releases/download/$tag/heroku-nodejs-plugin-node-8-$tag.tar.gz" "$dir/heroku-nodejs-plugin-node-8.tar.gz"
+
+    # Node 9
+    download "https://github.com/heroku/heroku-nodejs-plugin/releases/download/$tag/heroku-nodejs-plugin-node-9-$tag.sha512" "$dir/heroku-nodejs-plugin-node-9.sha512"
+    download "https://github.com/heroku/heroku-nodejs-plugin/releases/download/$tag/heroku-nodejs-plugin-node-9-$tag.tar.gz" "$dir/heroku-nodejs-plugin-node-9.tar.gz"
+
+    # Node 10 
+    download "https://github.com/heroku/heroku-nodejs-plugin/releases/download/$tag/heroku-nodejs-plugin-node-10-$tag.sha512" "$dir/heroku-nodejs-plugin-node-10.sha512"
+    download "https://github.com/heroku/heroku-nodejs-plugin/releases/download/$tag/heroku-nodejs-plugin-node-10-$tag.tar.gz" "$dir/heroku-nodejs-plugin-node-10.tar.gz"
+}
+
+test_hash() {
+    local major=${1}
+    local dir=${2}
+
+    local downloaded_sha=$(cat $dir/heroku-nodejs-plugin-node-$major.sha512 | awk '{print substr($0,0,128)}')
+    local binary_sha=$(shasum -a 512 $dir/heroku-nodejs-plugin-node-$major.tar.gz | awk '{print substr($0,0,128)}')
+
+    if [[ "$downloaded_sha" != "$binary_sha" ]]; then
+        echo "Invalid SHA for file: $dir/heroku-nodejs-plugin-node-$major.tar.gz"
+        exit 1
+    else
+        echo "Verified SHA for file: $dir/heroku-nodejs-plugin-node-$major.tar.gz"
+    fi
+}
+
+trap 'handle_failure' ERR
+
+if [[ -z $TAG_NAME ]]; then
+    TAG_NAME=$(get_latest_release)
+fi
+
+echo "Removing any old versions of the plugin"
+delete_old_plugin $PLUGIN_DIR
+
+echo "Downloading plugins"
+download_assets_for_release $TAG_NAME $PLUGIN_DIR
+echo $TAG_NAME > "$PLUGIN_DIR/version"
+
+echo "Plugins downloaded"
+
+test_hash 8 $PLUGIN_DIR
+test_hash 9 $PLUGIN_DIR
+test_hash 10 $PLUGIN_DIR
+
+echo "Done"

plugin/heroku-nodejs-plugin-node-10.sha512

+34990097468575e5a46d805a7cf4de471a29834f8c6f3513cd11c00b641654682e72adbab82bb15590643eb8203be45b294a912e28a0b7984a149fd0d4da4fd4  heroku-nodejs-plugin-node-10-v2.tar.gz

plugin/heroku-nodejs-plugin-node-8.sha512

+29d68a7d6a41499c9d3f9d1ed5e56a827ae5dc3ce43ed55822cf1c6bdddbe1ba65fee3871c3f272414b39255e0a81538cae83f79e8899aef57095d02bdf2d401  heroku-nodejs-plugin-node-8-v2.tar.gz

plugin/heroku-nodejs-plugin-node-9.sha512

+2d0586809344cf1272cf2389df11df3d3398e6d75e86ce90447031d42d33c8d8c2ff60a7be9bb4fdbf7e557f91ce828f8d2db20aaf2d94458f6a6d5460041abf  heroku-nodejs-plugin-node-9-v2.tar.gz

plugin/version

+v2

profile/nodejs.sh

 export PATH="$HOME/.heroku/node/bin:$HOME/.heroku/yarn/bin:$PATH:$HOME/bin:$HOME/node_modules/.bin"
 export NODE_HOME="$HOME/.heroku/node"
 export NODE_ENV=${NODE_ENV:-production}
+
+# If the metrics url is not present, this is the wrong type of dyno, or the user has opted out, 
+# don't include the metrics plugin
+if [[ -n "$HEROKU_METRICS_URL" ]] && [[ "${DYNO}" != run\.* ]] && [[ -z "$HEROKU_SKIP_NODE_PLUGIN" ]]; then
+
+  # Don't clobber NODE_OPTIONS if the user has set it, just add the require flag to the end
+  if [[ -z "$NODE_OPTIONS" ]]; then
+      export NODE_OPTIONS="--require $HOME/.heroku/heroku-nodejs-plugin"
+  else
+      export NODE_OPTIONS="${NODE_OPTIONS} --require $HOME/.heroku/heroku-nodejs-plugin"
+  fi
+
+fi

test/run

@@ -891,6 +891,61 @@ testNpmPrune56Issue() {
   assertCapturedSuccess
 }
 
+testPluginInstallationBuildTime() {
+  # The plugin should be installed for Node 8, 9, 10
+  compile "node-8"
+  assertFileExists "${compile_dir}/.heroku/heroku-nodejs-plugin/heroku-nodejs-plugin.node"
+
+  compile "node-9"
+  assertFileExists "${compile_dir}/.heroku/heroku-nodejs-plugin/heroku-nodejs-plugin.node"
+
+  compile "node-10"
+  assertFileExists "${compile_dir}/.heroku/heroku-nodejs-plugin/heroku-nodejs-plugin.node"
+
+  # but not for earlier versions
+  compile "node-6"
+  assertFileDoesNotExist "${compile_dir}/.heroku/heroku-nodejs-plugin/heroku-nodejs-plugin.node"
+}
+
+testPluginInstallationRunTime() {
+  local env_dir=$(mktmpdir)
+  compile "node-8" "$(mktmpdir)" $env_dir
+
+  # by default $NODE_OPTIONS is unmodifed
+  executeStartup $env_dir
+  assertEquals "" "$NODE_OPTIONS"
+  cleanupStartup
+
+  # If $HEROKU_METRICS_URL is defined at run time, the script
+  # should add a require statement to $NODE_OPTIONS
+  export HEROKU_METRICS_URL=https://localhost:5000
+  executeStartup $env_dir
+  assertEquals "--require $compile_dir/.heroku/heroku-nodejs-plugin" "$NODE_OPTIONS"
+  cleanupStartup
+
+  # unless $HEROKU_SKIP_NODE_PLUGIN is defined
+  export HEROKU_METRICS_URL=https://localhost:5000
+  export HEROKU_SKIP_NODE_PLUGIN=true
+  executeStartup $env_dir
+  assertEquals "" "$NODE_OPTIONS"
+  cleanupStartup
+
+  # if $NODE_OPTIONS already exists, it will append the require command
+  export HEROKU_METRICS_URL=https://localhost:5000
+  export NODE_OPTIONS="--max-old-space-size=128"
+  executeStartup $env_dir
+  assertEquals "--max-old-space-size=128 --require $compile_dir/.heroku/heroku-nodejs-plugin" "$NODE_OPTIONS"
+  cleanupStartup
+
+  # and it will leave it unchanged if $HEROKU_SKIP_NODE_PLUGIN is defined
+  export HEROKU_METRICS_URL=https://localhost:5000
+  export NODE_OPTIONS="--max-old-space-size=128"
+  export HEROKU_SKIP_NODE_PLUGIN=true
+  executeStartup $env_dir
+  assertEquals "--max-old-space-size=128" "$NODE_OPTIONS"
+  cleanupStartup
+}
+
 # Utils
 
 pushd $(dirname 0) >/dev/null
@@ -928,6 +983,32 @@ compile() {
   capture ${bp_dir}/bin/compile ${compile_dir} ${2:-$(mktmpdir)} $3
 }
 
+# This is meant to be run after `compile`. `cleanupStartup` must be run
+# after this function is called before other tests are executed
+executeStartup() {
+  local env_dir=$1
+
+  # On Heroku, $HOME is the /app dir, so we need to set it to
+  # the compile_dir here
+  export HOME=${compile_dir}
+
+  # we need to set any environment variables set via the env_dir and run
+  # all of the .profile.d scripts
+  export_env_dir $env_dir
+
+  for f in ${compile_dir}/.profile.d/*; do source $f > /dev/null 2> /dev/null ; done
+}
+
+cleanupStartup() {
+  unset HOME
+  unset NODE_ENV
+  unset NODE_HOME
+  unset NODE_OPTIONS
+  unset DYNO
+  unset HEROKU_METRICS_URL
+  unset HEROKU_SKIP_NODE_PLUGIN
+}
+
 compileTest() {
   default_process_types_cleanup