Class: Raptor::Http2

Inherits:
Object
  • Object
show all
Defined in:
lib/raptor/http2.rb,
sig/generated/raptor/http2.rbs

Overview

Handles HTTP/2 request processing and Rack application integration.

Http2 manages the HTTP/2 protocol lifecycle including frame processing, HPACK header compression, stream management, and response writing. It integrates with the same reactor, ractor pool, and thread pool pipeline used by HTTP/1.1 connections.

Defined Under Namespace

Classes: FlowControl, Writer

Constant Summary collapse

EAGER_READ_TIMEOUT =

Returns:

  • (::Float)
0.001
EAGER_READ_BUFFER_SIZE =

Returns:

  • (Object)
64 * 1024
EAGER_MAX_ROUNDS =

Returns:

  • (::Integer)
4
FLAG_END_STREAM =

Returns:

  • (::Integer)
0x1
FLAG_END_HEADERS =

Returns:

  • (::Integer)
0x4
FLAG_ACK =

Returns:

  • (::Integer)
0x1
FLAG_PRIORITY =

Returns:

  • (::Integer)
0x20
ERROR_NO_ERROR =

Returns:

  • (::Integer)
0x0
ERROR_PROTOCOL_ERROR =

Returns:

  • (::Integer)
0x1
DEFAULT_WINDOW_SIZE =

Returns:

  • (::Integer)
65_535
MAX_FRAME_SIZE =

Returns:

  • (::Integer)
16_384
SERVER_PROTOCOL =

Returns:

  • (::String)
"HTTP/2"
RACK_HEADER_PREFIX =

Returns:

  • (::String)
"rack."
HOP_BY_HOP_HEADERS =

Returns:

  • (Object)
["connection", "transfer-encoding", "keep-alive", "upgrade", "proxy-connection"].freeze
REQUEST_PSEUDO_HEADERS =

Returns:

  • (Object)
[":method", ":scheme", ":path", ":authority"].freeze
REQUIRED_REQUEST_PSEUDO_HEADERS =

Returns:

  • (Object)
[":method", ":scheme", ":path"].freeze

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(app, server_port, connection_options: {}, http2_options: {}, access_log_io: nil, on_error: nil) ⇒ Http2

Creates a new Http2 handler.

Parameters:

  • app (#call)

    the Rack application to dispatch requests to

  • server_port (Integer)

    port number used to populate SERVER_PORT in the Rack env

  • connection_options (Hash) (defaults to: {})

    per-connection settings shared across protocols

  • http2_options (Hash) (defaults to: {})

    HTTP/2-specific settings

  • access_log_io (IO, nil) (defaults to: nil)

    IO to write Common Log Format access entries to, or nil to disable

  • on_error (#call, nil) (defaults to: nil)

    callback invoked with (env, exception) when the Rack app raises

  • connection_options: (Hash[Symbol, untyped]) (defaults to: {})
  • http2_options: (Hash[Symbol, untyped]) (defaults to: {})
  • access_log_io: (IO, nil) (defaults to: nil)
  • on_error: (^(Hash[String, untyped]?, Exception) -> void, nil) (defaults to: nil)

Options Hash (connection_options:):

  • :write_timeout (Integer)

    per-write socket timeout in seconds

Options Hash (http2_options:):

  • :max_concurrent_streams (Integer)

    maximum HTTP/2 concurrent streams per connection



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# File 'lib/raptor/http2.rb', line 308

def initialize(app, server_port, connection_options: {}, http2_options: {}, access_log_io: nil, on_error: nil)
  @app = app
  @server_port = server_port
  @write_timeout = connection_options[:write_timeout] || Http::WRITE_TIMEOUT
  @access_log_io = access_log_io
  @on_error = on_error

  parser = Http2Parser.new
  settings_payload = parser.build_settings(
    max_concurrent_streams: http2_options[:max_concurrent_streams],
    initial_window_size: DEFAULT_WINDOW_SIZE
  )
  @initial_settings_frame = parser.build_frame(:settings, 0, 0, settings_payload).freeze
end

Instance Attribute Details

#initial_settings_frameString (readonly)

The initial server SETTINGS frame sent on every new HTTP/2 connection.

Returns:

  • (String)

    the encoded SETTINGS frame



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# File 'lib/raptor/http2.rb', line 293

def initial_settings_frame
  @initial_settings_frame
end

Class Method Details

.invalid_pseudo_headers?(headers) ⇒ Boolean

Returns true when a decoded header block violates the HTTP/2 pseudo-header rules from RFC 9113 section 8.3: an unknown pseudo-header, a duplicate pseudo-header, a pseudo-header appearing after any regular header, or a required pseudo-header (:method, :scheme, :path) missing on non-CONNECT requests.

Parameters:

  • headers (Array<Array(String, String)>)

    decoded header pairs

Returns:

  • (Boolean)


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# File 'lib/raptor/http2.rb', line 263

def self.invalid_pseudo_headers?(headers)
  seen_pseudo = {}
  seen_regular = false

  headers.each do |name, _value|
    if name.start_with?(":")
      return true if seen_regular
      return true unless REQUEST_PSEUDO_HEADERS.include?(name)
      return true if seen_pseudo[name]
      seen_pseudo[name] = true
    else
      seen_regular = true
    end
  end

  return false if seen_pseudo[":method"] && headers.assoc(":method")&.last == "CONNECT"

  REQUIRED_REQUEST_PSEUDO_HEADERS.any? { |name| !seen_pseudo[name] }
end

.process_frames(data) ⇒ Hash

Processes HTTP/2 frames from the connection buffer.

Parses frames, handles HPACK decoding, tracks stream state, and returns updated connection state along with any outgoing protocol frames and completed stream requests. Ractor-safe.

Parameters:

  • data (Hash)

    the connection state including buffer and HPACK table

Returns:

  • (Hash)

    updated state with outgoing_frames and completed_requests



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# File 'lib/raptor/http2.rb', line 342

def self.process_frames(data)
  parser = Http2Parser.new
  buffer = data[:buffer]
  hpack_table = data[:hpack_table] || []
  streams = data[:http2_streams] ? data[:http2_streams].dup : {}
  outgoing_frames = []
  completed_requests = []
  window_updates = []
  peer_initial_window_size = nil
  connection_window = data[:http2_window] || DEFAULT_WINDOW_SIZE
  preface_received = data[:http2_preface_received] || false
  last_client_stream_id = data[:http2_last_client_stream_id] || 0
  pending_headers = data[:http2_pending_headers]
  goaway_error = nil

  unless preface_received
    if buffer.bytesize >= 24 && buffer.byteslice(0, 24) == Http2Parser.connection_preface
      buffer = buffer.byteslice(24..-1) || ""
      preface_received = true
    else
      return build_result(data, buffer, hpack_table, streams, outgoing_frames, completed_requests, window_updates, peer_initial_window_size, connection_window, preface_received, last_client_stream_id, pending_headers, false)
    end
  end

  loop do
    parsed = parser.parse_frame(buffer)
    break unless parsed

    frame, consumed = parsed
    buffer = buffer.byteslice(consumed..-1) || ""

    if pending_headers && frame[:type] != :continuation
      goaway_error = ERROR_PROTOCOL_ERROR
      break
    end

    case frame[:type]
    when :settings
      if (frame[:flags] & FLAG_ACK).zero?
        parsed_settings = parser.parse_settings(frame[:payload])
        peer_initial_window_size = parsed_settings[:initial_window_size] if parsed_settings.key?(:initial_window_size)
        outgoing_frames << parser.build_frame(:settings, FLAG_ACK, 0, nil)
      end

    when :headers
      stream_id = frame[:stream_id]
      header_payload = frame[:payload]

      unless streams.key?(stream_id)
        if stream_id.even? || stream_id <= last_client_stream_id
          goaway_error = ERROR_PROTOCOL_ERROR
          break
        end
        last_client_stream_id = stream_id
      end

      if (frame[:flags] & FLAG_PRIORITY) != 0
        header_payload = header_payload.byteslice(5..-1) || ""
      end

      end_stream = (frame[:flags] & FLAG_END_STREAM) != 0

      if (frame[:flags] & FLAG_END_HEADERS) != 0
        decoded_headers, hpack_table = parser.parse_headers(header_payload, hpack_table)
        if invalid_pseudo_headers?(decoded_headers)
          streams.delete(stream_id)
          outgoing_frames << parser.build_frame(:rst_stream, 0, stream_id, [ERROR_PROTOCOL_ERROR].pack("N"))
        else
          streams, completed_requests = finalize_headers(streams, completed_requests, stream_id, decoded_headers, end_stream)
        end
      else
        pending_headers = { stream_id: stream_id, buffer: header_payload, end_stream: end_stream }
      end

    when :continuation
      if pending_headers.nil? || frame[:stream_id] != pending_headers[:stream_id]
        goaway_error = ERROR_PROTOCOL_ERROR
        break
      end

      pending_headers = pending_headers.merge(buffer: pending_headers[:buffer] + frame[:payload])

      if (frame[:flags] & FLAG_END_HEADERS) != 0
        stream_id = pending_headers[:stream_id]
        decoded_headers, hpack_table = parser.parse_headers(pending_headers[:buffer], hpack_table)
        if invalid_pseudo_headers?(decoded_headers)
          streams.delete(stream_id)
          outgoing_frames << parser.build_frame(:rst_stream, 0, stream_id, [ERROR_PROTOCOL_ERROR].pack("N"))
        else
          streams, completed_requests = finalize_headers(streams, completed_requests, stream_id, decoded_headers, pending_headers[:end_stream])
        end
        pending_headers = nil
      end

    when :data
      stream_id = frame[:stream_id]

      unless streams.key?(stream_id)
        goaway_error = ERROR_PROTOCOL_ERROR
        break
      end

      stream = streams[stream_id]
      existing_body = stream[:body] || ""
      stream = stream.merge(body: existing_body + frame[:payload])

      if frame[:payload].bytesize.positive?
        connection_window -= frame[:payload].bytesize
        if connection_window < DEFAULT_WINDOW_SIZE / 2
          increment = DEFAULT_WINDOW_SIZE - connection_window
          wu_payload = [increment].pack("N")
          outgoing_frames << parser.build_frame(:window_update, 0, 0, wu_payload)
          outgoing_frames << parser.build_frame(:window_update, 0, stream_id, wu_payload)
          connection_window += increment
        end
      end

      if (frame[:flags] & FLAG_END_STREAM) != 0
        stream_headers = stream[:headers] || []
        completed_requests << {
          stream_id: stream_id,
          headers: stream_headers,
          body: stream[:body]
        }

        streams.delete(stream_id)
      else
        streams[stream_id] = stream
      end

    when :window_update
      increment = parser.parse_window_update(frame[:payload])
      window_updates << [frame[:stream_id], increment]

    when :ping
      if (frame[:flags] & FLAG_ACK).zero?
        outgoing_frames << parser.build_frame(:ping, FLAG_ACK, 0, frame[:payload])
      end

    when :goaway
      break

    when :rst_stream
      streams.delete(frame[:stream_id])
    end
  end

  if goaway_error
    goaway_payload = [last_client_stream_id, goaway_error].pack("NN")
    outgoing_frames << parser.build_frame(:goaway, 0, 0, goaway_payload)
  end

  build_result(data, buffer, hpack_table, streams, outgoing_frames, completed_requests, window_updates, peer_initial_window_size, connection_window, preface_received, last_client_stream_id, pending_headers, !goaway_error.nil?)
end

Instance Method Details

#apply_flow_control_updates(flow_control, result) ⇒ void

This method returns an undefined value.

Applies inbound flow-control updates from a parsed result to the connection's FlowControl.

Parameters:

  • flow_control (FlowControl)

    the per-connection flow controller

  • result (Hash)

    the parsed result from process_frames



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# File 'lib/raptor/http2.rb', line 637

def apply_flow_control_updates(flow_control, result)
  result[:window_updates]&.each do |stream_id, increment|
    if stream_id.zero?
      flow_control.add_connection_window(increment)
    else
      flow_control.add_stream_window(stream_id, increment)
    end
  end

  if (new_size = result[:peer_initial_window_size])
    flow_control.set_initial_stream_window(new_size)
  end
end

#build_rack_env(headers, body, remote_addr:) ⇒ Hash

Builds a Rack environment hash from HTTP/2 headers and body.

Translates HTTP/2 pseudo-headers into Rack-compatible environment keys and populates all required Rack env entries.

Parameters:

  • headers (Array<Array(String, String)>)

    HTTP/2 header pairs

  • body (String)

    the request body

  • remote_addr (String)

    the client IP address

  • remote_addr: (String)

Returns:

  • (Hash)

    fully populated Rack environment hash



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# File 'lib/raptor/http2.rb', line 817

def build_rack_env(headers, body, remote_addr:)
  env = {}

  headers.each do |name, value|
    if name.start_with?(":")
      case name
      when ":method"    then env[Rack::REQUEST_METHOD] = value
      when ":path"
        path, query = value.split("?", 2)
        env[Rack::PATH_INFO] = path
        env[Rack::QUERY_STRING] = query || ""
      when ":scheme"    then env[Rack::RACK_URL_SCHEME] = value
      when ":authority" then env[Rack::HTTP_HOST] = value
      end
    elsif name == "content-type"
      env[Http::CONTENT_TYPE] = value
    elsif name == "content-length"
      env[Http::CONTENT_LENGTH] = value
    else
      rack_key = "HTTP_#{name.upcase.tr("-", "_")}"
      env[rack_key] = value
    end
  end

  env[Rack::SERVER_PROTOCOL] = SERVER_PROTOCOL
  env[Rack::RACK_VERSION] = Rack::VERSION
  env[Rack::RACK_INPUT] = StringIO.new(body).set_encoding(Encoding::ASCII_8BIT)
  env[Rack::RACK_ERRORS] = $stderr
  env[Rack::RACK_RESPONSE_FINISHED] = []
  env[Rack::RACK_IS_HIJACK] = false

  env[Rack::SCRIPT_NAME] = "" unless env.key?(Rack::SCRIPT_NAME)
  env[Rack::PATH_INFO] = "" unless env.key?(Rack::PATH_INFO)
  env[Rack::QUERY_STRING] = "" unless env.key?(Rack::QUERY_STRING)

  if body.bytesize.positive? && !env.key?(Http::CONTENT_LENGTH)
    env[Http::CONTENT_LENGTH] = body.bytesize.to_s
  end

  env[Http::REMOTE_ADDR] = remote_addr
  env[Http::SERVER_SOFTWARE] = Http::SERVER_SOFTWARE_VALUE
  env[Http::HTTP_VERSION] = SERVER_PROTOCOL

  populate_server_name_and_port(env)

  env
end

#create_writerWriter

Creates a per-connection Writer configured with the handler's write timeout.

Returns:

  • (Writer)

    a new per-connection frame writer



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# File 'lib/raptor/http2.rb', line 328

def create_writer
  Writer.new(write_timeout: @write_timeout)
end

#dispatch_stream_request(socket, writer, flow_control, stream_id, headers, body, remote_addr:) ⇒ void

This method returns an undefined value.

Dispatches a completed stream request to the Rack app and writes the response back as HTTP/2 frames.

Parameters:

  • socket (OpenSSL::SSL::SSLSocket)

    the connection socket

  • writer (Writer)

    lock-free frame writer for the connection

  • flow_control (FlowControl)

    per-connection outbound flow controller

  • stream_id (Integer)

    the HTTP/2 stream identifier

  • headers (Array<Array(String, String)>)

    request headers

  • body (String)

    request body

  • remote_addr (String)

    the client IP address

  • remote_addr: (String)


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# File 'lib/raptor/http2.rb', line 690

def dispatch_stream_request(socket, writer, flow_control, stream_id, headers, body, remote_addr:)
  env = build_rack_env(headers, body, remote_addr: remote_addr)
  status, response_headers, response_body = @app.call(env)

  response_size = write_http2_response(socket, writer, flow_control, stream_id, status, response_headers, response_body)
  write_access_log(env, status, response_size, remote_addr) if @access_log_io
rescue => error
  write_http2_error_response(socket, writer, stream_id)

  if @on_error
    @on_error.call(env, error) rescue nil
  else
    raise
  end
ensure
  response_body.close if response_body.respond_to?(:close)
  flow_control.discard_stream(stream_id) if flow_control
end

#eager_read_next_batch(socket) ⇒ String?

Reads the next frame batch from socket within a short window, or returns nil if nothing arrives in time.

Parameters:

  • socket (OpenSSL::SSL::SSLSocket)

    the connection socket

Returns:

  • (String, nil)

    the bytes read, or nil if nothing was available



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# File 'lib/raptor/http2.rb', line 658

def eager_read_next_batch(socket)
  return unless socket.wait_readable(EAGER_READ_TIMEOUT)

  data = begin
    socket.read_nonblock(EAGER_READ_BUFFER_SIZE)
  rescue IO::WaitReadable, EOFError, IOError
    return
  end

  buffer = String.new
  buffer << data

  while socket.pending > 0
    buffer << socket.read_nonblock(socket.pending)
  end

  buffer
end

#handle_parsed_request(result, reactor, thread_pool) ⇒ void

This method returns an undefined value.

Handles a parsed HTTP/2 request from the ractor pool.

Writes outgoing protocol frames to the socket, updates reactor state, and dispatches completed stream requests to the thread pool. Eagerly consumes subsequent frame batches that are already buffered, skipping the reactor and ractor pool hops while the connection is hot.

Parameters:

  • result (Hash)

    the parsed result from the ractor pool

  • reactor (Reactor)

    the reactor managing the connection

  • thread_pool (AtomicThreadPool)

    thread pool for Rack app dispatch



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# File 'lib/raptor/http2.rb', line 582

def handle_parsed_request(result, reactor, thread_pool)
  socket = reactor.socket_for(result[:id])
  return unless socket

  writer = reactor.writer_for(result[:id])
  flow_control = reactor.flow_control_for(result[:id])

  rounds = 0
  loop do
    if flow_control && (result[:window_updates] || result[:peer_initial_window_size])
      apply_flow_control_updates(flow_control, result)
    end

    writer.write_frames(socket, result[:outgoing_frames])

    if result[:close_connection]
      reactor.close_connection(result[:id])
      return
    end

    result[:completed_requests]&.each do |request|
      stream_id = request[:stream_id]
      remote_addr = result[:remote_addr] || Server::DEFAULT_REMOTE_ADDR

      thread_pool << proc do
        dispatch_stream_request(
          socket, writer, flow_control, stream_id,
          request[:headers], request[:body],
          remote_addr: remote_addr
        )
      end
    end

    rounds += 1
    break if rounds >= EAGER_MAX_ROUNDS

    next_batch = eager_read_next_batch(socket)
    break unless next_batch

    result = Raptor::Http2.process_frames(result.merge(buffer: result[:buffer] + next_batch))
  end

  reactor.update_http2_state(result)
end

#populate_server_name_and_port(env) ⇒ void

This method returns an undefined value.

Populates SERVER_NAME and SERVER_PORT from the HTTP_HOST header.

Parameters:

  • env (Hash)

    the Rack environment to populate



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# File 'lib/raptor/http2.rb', line 871

def populate_server_name_and_port(env)
  http_host = env[Rack::HTTP_HOST]

  if http_host
    if http_host.start_with?("[")
      host = http_host[/\A\[([^\]]+)\]/, 1]
      port = http_host[/\]:(\d+)\z/, 1]
    else
      host, port = http_host.split(":", 2)
    end
    env[Rack::SERVER_NAME] ||= host
    env[Rack::SERVER_PORT] ||= port || @server_port.to_s
  else
    env[Rack::SERVER_NAME] ||= Server::DEFAULT_SERVER_NAME
    env[Rack::SERVER_PORT] ||= @server_port.to_s
  end
end

#write_access_log(env, status, size, remote_addr) ⇒ void

This method returns an undefined value.

Instance-level wrapper around Raptor::Http.write_access_log that routes to the configured @access_log_io.

Parameters:

  • env (Hash)

    the Rack environment

  • status (Integer)

    the response status code

  • size (String)

    the response body size in bytes, or - if unknown

  • remote_addr (String)

    the client IP address



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# File 'lib/raptor/http2.rb', line 802

def write_access_log(env, status, size, remote_addr)
  Http.write_access_log(@access_log_io, env, status, size, remote_addr)
end

#write_http2_error_response(socket, writer, stream_id) ⇒ void

This method returns an undefined value.

Writes a 500 error response as HTTP/2 frames.

Parameters:

  • socket (OpenSSL::SSL::SSLSocket)

    the connection socket

  • writer (Writer)

    lock-free frame writer for the connection

  • stream_id (Integer)

    the HTTP/2 stream identifier



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# File 'lib/raptor/http2.rb', line 782

def write_http2_error_response(socket, writer, stream_id)
  parser = Http2Parser.new
  encoded = parser.encode_headers([[":status", "500"]])

  writer.write_frames(
    socket,
    [parser.build_frame(:headers, FLAG_END_STREAM | FLAG_END_HEADERS, stream_id, encoded)]
  )
end

#write_http2_response(socket, writer, flow_control, stream_id, status, headers, body) ⇒ String

Writes a Rack response as HTTP/2 frames to the socket.

DATA frames are partitioned through flow_control so each write fits within the peer's per-stream and connection windows.

Parameters:

  • socket (OpenSSL::SSL::SSLSocket)

    the connection socket

  • writer (Writer)

    lock-free frame writer for the connection

  • flow_control (FlowControl)

    per-connection outbound flow controller

  • stream_id (Integer)

    the HTTP/2 stream identifier

  • status (Integer)

    HTTP status code

  • headers (Hash)

    response headers from the Rack application

  • body (Object)

    response body responding to each

Returns:

  • (String)

    the response body size in bytes



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# File 'lib/raptor/http2.rb', line 724

def write_http2_response(socket, writer, flow_control, stream_id, status, headers, body)
  parser = Http2Parser.new

  header_pairs = [[":status", status.to_s]]
  headers.each do |name, value|
    lowered = name.downcase
    next if lowered.start_with?(RACK_HEADER_PREFIX)
    next if HOP_BY_HOP_HEADERS.include?(lowered)

    if value.is_a?(Array)
      value.each { |entry| header_pairs << [lowered, entry.to_s] }
    else
      header_pairs << [lowered, value.to_s]
    end
  end

  encoded_headers = parser.encode_headers(header_pairs)
  body_chunks = []
  body_bytes = 0
  body.each do |chunk|
    next if chunk.empty?
    body_chunks << chunk
    body_bytes += chunk.bytesize
  end

  if body_chunks.empty?
    writer.write_frames(socket, [parser.build_frame(:headers, FLAG_END_STREAM | FLAG_END_HEADERS, stream_id, encoded_headers)])
    return "0"
  end

  frames = [parser.build_frame(:headers, FLAG_END_HEADERS, stream_id, encoded_headers)]

  last_chunk_index = body_chunks.size - 1
  body_chunks.each_with_index do |chunk, chunk_index|
    offset = 0
    while offset < chunk.bytesize
      remaining = chunk.bytesize - offset
      last_frame = chunk_index == last_chunk_index && remaining <= MAX_FRAME_SIZE
      granted = flow_control.acquire(stream_id, remaining, end_stream: last_frame)
      slice = offset == 0 && granted == chunk.bytesize ? chunk : chunk.byteslice(offset, granted)
      offset += granted
      end_stream = chunk_index == last_chunk_index && offset == chunk.bytesize
      frames << parser.build_frame(:data, end_stream ? FLAG_END_STREAM : 0, stream_id, slice)
    end
  end

  writer.write_frames(socket, frames)
  body_bytes.to_s
end