perf.rake

namespace :perf do
  task :rails_load do
    ENV["RAILS_ENV"] ||= "production"
    ENV['RACK_ENV']  = ENV["RAILS_ENV"]
    ENV["DISABLE_SPRING"] = "true"
    ENV["SECRET_KEY_BASE"] ||= "foofoofoo"
    ENV['LOG_LEVEL'] ||= "FATAL"

    require 'rails'

    puts "Booting: #{Rails.env}"

    %W{ . lib test config }.each do |file|
      $LOAD_PATH << file
    end

    require 'application'

    Rails.env = ENV["RAILS_ENV"]

    APP = Rails.application

    if APP.respond_to?(:initialized?)
      APP.initialize! unless APP.initialized?
    else
      APP.initialize! unless APP.instance_variable_get(:@initialized)
    end

    if ENV["DERAILED_SKIP_ACTIVE_RECORD"] && defined? ActiveRecord
      ActiveRecord::Tasks::DatabaseTasks.create_current
      ActiveRecord::Migrator.migrations_paths = APP.paths['db/migrate'].to_a
      ActiveRecord::Migration.verbose = true
      ActiveRecord::Migrator.migrate(ActiveRecord::Migrator.migrations_paths, nil)
    end

    APP.config.consider_all_requests_local = true
  end

  task :setup => [:rails_load] do
    require 'derailed_benchmarks'

    TEST_COUNT  = (ENV['TEST_COUNT'] || ENV['CNT'] || 1_000).to_i
    PATH_TO_HIT = ENV["PATH_TO_HIT"] || ENV['ENDPOINT'] || "/"
    puts "Endpoint: #{ PATH_TO_HIT.inspect }"

    require 'rack/test'
    require 'rack/file'

    def get_path
      File.join("/", URI.escape(PATH_TO_HIT))
    end

    DERAILED_APP = DerailedBenchmarks.add_auth(APP)
    if server = ENV["USE_SERVER"]
      @port = (3000..3900).to_a.sample
      puts "Port: #{ @port.inspect }"
      puts "Server: #{ server.inspect }"
      puts "Disable SSL: #{ENV['DISABLE_SSL']}"

      thread = Thread.new do
        Rack::Server.start(
          app: DERAILED_APP,
          Port: @port,
          environment: 'none',
          server: server
        )
      end
      sleep 1
      puts "serving: http://localhost:#{@port}#{get_path}"

      def call_app(path = get_path)
        cmd = "curl 'http://localhost:#{@port}#{path}' -g -s --fail 2>&1"
        response = `#{cmd}`
        unless $? && $?.success?
          raise "Bad request to #{cmd.inspect} Response:\n#{ response.inspect }"
        end
      end
    else
      @app = Rack::MockRequest.new(DERAILED_APP)
      def call_app
        response = @app.get(get_path, ENV.to_h)
        unless response.status == 200
          raise "Bad request: #{ response }"
        end
        response
      end
    end
  end
  desc "stackprof"
  task :stackprof => [:setup] do
    require 'stackprof'
    TEST_COUNT = (ENV["TEST_COUNT"] ||= "100").to_i
    file = "tmp/#{Time.now.iso8601}-stackprof-cpu-myapp.dump"

    # Available profiling modes:
    # - :wall
    # - :cpu
    # - :object
    StackProf.run(mode: :wall, out: file) do
      Rake::Task["perf:test"].invoke
    end
    cmd = "stackprof #{file}"
    puts "Running `#{cmd}`. Execute `stackprof --help` for more info"
    puts `#{cmd}`
  end
end