Heroku build time metrics

README.md

Deploy time metrics

See https://pilot.co/blog/how-to-start-fixing-your-heroku-deploy-time/.

Metrics

First, get Heroku OAuth token:

heroku plugins:install git@github.com:heroku/heroku-oauth.git
heroku authorizations:create -d 'Deployment metrics'

Set the env variable HEROKU_AUTH_TOKEN

export HEROKU_AUTH_TOKEN=…

or add it to your env management tool of choice (dotenv, figaro etc.)

After that, you’re able to run the Rake task:

bin/rake metrics:heroku
bin/rake metrics:heroku SINCE='23/05/2016 05:54:28'

heroku.rb

require 'platform-api'

class Metrics::Heroku
  def initialize(app_name)
    @app_name = app_name
  end

  attr_reader :app_name

  def api
    options = {default_headers: {'Range' => 'started_at ..; order=desc'}}
    @api ||= PlatformAPI.connect_oauth(ENV['HEROKU_AUTH_TOKEN'], options)
  end

  def builds
    all_builds.select { |b| b.succeeded? }
  end

  def all_builds
    raw_builds.map { |raw_build| Build.new(raw_build) }
  end

  def raw_builds
    api.build.list(app_name).lazy
  end

  class Build < OpenStruct
    def succeeded?
      self.status == 'succeeded'
    end

    def created_at
      super.to_time.utc
    end

    alias_method :started_at, :created_at

    def updated_at
      super.to_time.utc
    end

    alias_method :finished_at, :updated_at

    def duration
      (finished_at - started_at).to_f
    end

    def build_log
      @build_log ||= BuildLog.new(Excon.get(output_stream_url).body) unless @build_log_failed
    rescue Excon::Errors::Error
      @build_log_failed = true
    end

    delegate :npm_install_time,
             :bundler_time,
             :webpack_time,
             :sprockets_time,
             :migrations_time,
             :total_known_time,
             to: :build_log, allow_nil: true

    def unknown_time
      duration - total_known_time if build_log
    end
  end

  class BuildLog
    attr_reader :log

    def initialize(log)
      @log = log
    end

    def npm_install_started_at
      if log =~ /^\s+([a-zA-Z0-9: ]+) Starting npm install/
        Time.parse($1)
      end
    end

    def npm_install_finished_at
      if log =~ /^\s+([a-zA-Z0-9: ]+) Finished npm install/
        Time.parse($1)
      end
    end

    def npm_install_time
      if npm_install_started_at && npm_install_finished_at
        npm_install_finished_at - npm_install_started_at
      end
    end

    def bundler_time
      scan(/Bundle completed \(([0-9.]+)s\)/).map(&:to_f).inject(&:+)
    end

    def webpack_time
      scan(/Version: webpack [0-9.]+\s+Time: (\d+)ms/).map(&:to_i).inject(&:+).to_f / 1000
    end

    def sprockets_time
      if webpack_time && assets_precompile_time
        assets_precompile_time - webpack_time
      else
        assets_precompile_time
      end
    end

    def assets_precompile_time
      scan(/Asset precompilation completed \(([0-9.]+)s\)/).map(&:to_f).inject(&:+)
    end

    def migrations_time
      scan(/migrated \(([0-9.]+)s\)/).map(&:to_f).inject(&:+) || 0
    end

    def total_known_time
      [
        npm_install_time,
        bundler_time,
        webpack_time,
        sprockets_time,
        migrations_time
      ].compact.inject(0.0, &:+)
    end

    private

    def scan(regexp)
      log.scan(regexp).map(&:first)
    end
  end
end

metrics.rake

require 'csv'
require Rails.root.join('lib', 'metrics', 'heroku')

namespace :metrics do
  desc 'Fetch deployment metrics from Heroku'
  task :heroku do
    since = ENV['SINCE'] && ENV['SINCE'].to_time(:utc)

    CSV.open('heroku.csv', 'w') do |csv|
      # Ensure we can preview the output with `tail -f heroku.csv`
      csv.sync = true

      csv << [
        'app',
        'created_at',
        'duration',
        'npm_install_time',
        'bundler_time',
        'webpack_time',
        'sprockets_time',
        'migrations_time',
        'unknown_time',
      ]

      # Insert Heroku app names here
      %w(production-app staging-app).each do |app_name|
        heroku = Metrics::Heroku.new(app_name)
        heroku.builds.each do |build|
          break if since && build.created_at <= since

          csv << [
            app_name,
            build.created_at.strftime("%Y-%m-%d %H:%M:%S"),
            build.duration,
            build.npm_install_time,
            build.bundler_time,
            build.webpack_time,
            build.sprockets_time,
            build.migrations_time,
            build.unknown_time,
          ]
          print '.'
        end
        puts
      end
    end
  end
end