Class: ReactOnRails::ServerRenderingPool::RubyEmbeddedJavaScript

Inherits:
Object
  • Object
show all
Defined in:
lib/react_on_rails/server_rendering_pool/ruby_embedded_java_script.rb

Overview

rubocop:disable Metrics/ClassLength

Constant Summary collapse

RENDERER_CONNECTION_ERROR_CLASSES =

Error classes that signal Rails could not reach the renderer process (e.g. the Pro Node renderer configured via REACT_RENDERER_URL) rather than the renderer evaluating the bundle and the bundle itself failing. See issue #3604.

Errno::EPERM is intentionally NOT in this list: it is a general “Operation not permitted” error (file permissions, process signals, privileged-port binds), so a class match — especially across the #cause chain — would misclassify a non-network EPERM (e.g. a bundle file read wrapped in ReactOnRails::Error) as a renderer connection failure. The sandboxed connect(2) EPERM from issue #3604 is matched instead by the “connect(2) for” branch of RENDERER_CONNECTION_ERROR_REGEX below (its message is “Operation not permitted - connect(2) for host:port”).

[
  SocketError,
  Errno::ECONNREFUSED,
  Errno::ECONNRESET,
  Errno::EHOSTUNREACH,
  Errno::ENETUNREACH,
  Errno::ETIMEDOUT,
  Errno::EPIPE
].freeze
RENDERER_CONNECTION_ERROR_REGEX =

Renderer-anchored connection signatures, used only as a fallback for failures that survive as text rather than as one of the Errno classes above. The Pro renderer client re-wraps transport failures as “<Connection|Time out> error on renderer request: …”, and raw Errno messages carry the “connect(2) for host:port” shape. These patterns are deliberately narrow (anchored to renderer/socket wording) so a genuine in-process bundle error whose text merely mentions a connection — e.g. a component’s own failed ‘fetch` during SSR reporting “ECONNREFUSED” — is NOT misclassified as a renderer connectivity problem. Structured cases are handled by the Errno classes above, checked across the error’s #cause chain. See issue #3604.

/
  connect\(2\)\sfor
  | Failed\sto\sopen\sTCP\sconnection
  | error\son\srenderer\srequest
/xi

Class Method Summary collapse

Class Method Details

.console_polyfill ⇒ Object

Reimplement console methods for replaying on the client Save a handle to the original console if needed.



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# File 'lib/react_on_rails/server_rendering_pool/ruby_embedded_java_script.rb', line 234

def console_polyfill
  <<~JS
    var debugConsole = console;
    var console = { history: [] };
    ['error', 'log', 'info', 'warn'].forEach(function (level) {
      console[level] = function () {
        var argArray = Array.prototype.slice.call(arguments);
        if (argArray.length > 0) {
          argArray[0] = '[SERVER] ' + argArray[0];
        }
        console.history.push({level: level, arguments: argArray});
      };
    });
  JS
end

.create_js_context ⇒ Object 



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# File 'lib/react_on_rails/server_rendering_pool/ruby_embedded_java_script.rb', line 163

def create_js_context
  return if ReactOnRails.configuration.server_bundle_js_file.blank?

  bundle_js_code = read_bundle_js_code
  base_js_code = <<~JS
    #{console_polyfill}
    #{execjs_timer_polyfills}
    #{bundle_js_code};
  JS

  file_name = "tmp/base_js_code.js"
  begin
    if ReactOnRails.configuration.trace
      Rails.logger.info do
        "[react_on_rails] Created JavaScript context with file " \
          "#{ReactOnRails::Utils.server_bundle_js_file_path}"
      end
    end
    ExecJS.compile(base_js_code)
  rescue StandardError => e
    msg = "ERROR when compiling base_js_code! " \
          "See file #{file_name} to " \
          "correlate line numbers of error. Error is\n\n#{e.message}" \
          "\n\n#{e.backtrace.join("\n")}" \
          "\n\n#{Utils.default_troubleshooting_section}"
    Rails.logger.error(msg)
    trace_js_code_used("Error when compiling JavaScript code for the context.", base_js_code,
                       file_name, force: true)
    raise e
  end
end

.eval_js(js_code, _render_options) ⇒ Object 



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# File 'lib/react_on_rails/server_rendering_pool/ruby_embedded_java_script.rb', line 143

def eval_js(js_code, _render_options)
  @js_context_pool.with do |js_context|
    js_context.eval(js_code)
  end
end

.exec_server_render_js(js_code, render_options, js_evaluator = nil) ⇒ Object

js_code: JavaScript expression that returns a string. render_options: lib/react_on_rails/react_component/render_options.rb Using these options:

trace: saves the executed JS to a file, used in development
logging_on_server: put on server logs, not just in browser console

Returns a Hash:

html: string of HTML for direct insertion on the page by evaluating js_code
consoleReplayScript: script for replaying console
hasErrors: true if server rendering errors

Note, js_code does not have to be based on React. js_code MUST RETURN json stringify Object Calling code will probably call ‘html_safe’ on return value before rendering to the view.



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# File 'lib/react_on_rails/server_rendering_pool/ruby_embedded_java_script.rb', line 89

def exec_server_render_js(js_code, render_options, js_evaluator = nil)
  js_evaluator ||= self
  if render_options.trace
    @file_index ||= 1
    trace_js_code_used("Evaluating code to server render.", js_code,
                       "tmp/server-generated-#{@file_index % 10}.js")
    @file_index += 1
  end
  begin
    result = if render_options.streaming?
               js_evaluator.eval_streaming_js(js_code, render_options)
             else
               js_evaluator.eval_js(js_code, render_options)
             end
  rescue ReactOnRails::ServerBundleLoadError
    raise
  rescue StandardError => err
    msg = if renderer_connection_error?(err)
            renderer_connection_error_message(err)
          else
            server_bundle_evaluation_error_message(err)
          end
    msg = "#{msg}\n#{Utils.default_troubleshooting_section}\n"
    raise ReactOnRails::Error, msg, err.backtrace
  end

  return parse_render_result(result, render_options) unless render_options.streaming?

  # Streamed chunks are Hashes (from LengthPrefixedParser in stream_request.rb).
  # Just replay console messages and pass through.
  result.transform do |chunk|
    replay_console_to_rails_logger(chunk, render_options)
    chunk
  end
end

.execjs_timer_polyfills ⇒ Object 



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# File 'lib/react_on_rails/server_rendering_pool/ruby_embedded_java_script.rb', line 195

def execjs_timer_polyfills
  <<~JS
    function getStackTrace () {
      var stack;
      try {
        throw new Error('');
      }
      catch (error) {
        stack = error.stack || '';
      }
      stack = stack.split('\\n').map(function (line) { return line.trim(); });
      return stack.splice(stack[0] == 'Error' ? 2 : 1);
    }

    function setInterval() {
      #{undefined_for_exec_js_logging('setInterval')}
    }

    function setTimeout() {
      #{undefined_for_exec_js_logging('setTimeout')}
    }

    function clearTimeout() {
      #{undefined_for_exec_js_logging('clearTimeout')}
    }
  JS
end

.read_bundle_js_code ⇒ Object 



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# File 'lib/react_on_rails/server_rendering_pool/ruby_embedded_java_script.rb', line 149

def read_bundle_js_code
  server_js_file = ReactOnRails::Utils.server_bundle_js_file_path
  if ReactOnRails::Utils.server_bundle_path_is_http?
    file_url_to_string(server_js_file)
  else
    File.read(server_js_file)
  end
rescue StandardError => e
  msg = "You specified server rendering JS file: #{server_js_file}, but it cannot be " \
        "read. You may set the server_bundle_js_file in your configuration to be \"\" to " \
        "avoid this warning.\nError is: #{e}\n\n#{Utils.default_troubleshooting_section}"
  raise ReactOnRails::ServerBundleLoadError, msg
end

.reset_pool ⇒ Object 



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# File 'lib/react_on_rails/server_rendering_pool/ruby_embedded_java_script.rb', line 48

def reset_pool
  @js_context_pool = ConnectionPool.new(
    size: ReactOnRails.configuration.server_renderer_pool_size,
    timeout: ReactOnRails.configuration.server_renderer_timeout
  ) { create_js_context }
end

.reset_pool_if_server_bundle_was_modified ⇒ Object 



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# File 'lib/react_on_rails/server_rendering_pool/ruby_embedded_java_script.rb', line 55

def reset_pool_if_server_bundle_was_modified
  return unless ReactOnRails.configuration.development_mode

  # RSC (React Server Components) bundle changes are not monitored here since:
  # 1. RSC is only supported in the Pro version of React on Rails
  # 2. This RubyEmbeddedJavaScript pool is used exclusively in the non-Pro version
  # 3. This pool uses ExecJS for JavaScript evaluation which does not support RSC
  if ReactOnRails::Utils.server_bundle_path_is_http?
    return if @server_bundle_url == ReactOnRails::Utils.server_bundle_js_file_path

    @server_bundle_url = ReactOnRails::Utils.server_bundle_js_file_path
  else
    file_mtime = File.mtime(ReactOnRails::Utils.server_bundle_js_file_path)
    @server_bundle_timestamp ||= file_mtime
    return if @server_bundle_timestamp == file_mtime

    @server_bundle_timestamp = file_mtime
  end
  ReactOnRails::ServerRenderingPool.reset_pool
end

.trace_js_code_used(msg, js_code, file_name = "tmp/server-generated.js", force: false) ⇒ Object 



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# File 'lib/react_on_rails/server_rendering_pool/ruby_embedded_java_script.rb', line 125

def trace_js_code_used(msg, js_code, file_name = "tmp/server-generated.js", force: false)
  return unless ReactOnRails.configuration.trace || force

  # Set to anything to print generated code.
  File.write(file_name, js_code)
  msg = <<~MSG
    #{'Z' * 80}
    [react_on_rails] #{msg}
    JavaScript code used: #{file_name}
    #{'Z' * 80}
  MSG
  if force
    Rails.logger.error(msg)
  else
    Rails.logger.info(msg)
  end
end

.undefined_for_exec_js_logging(function_name) ⇒ Object 



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# File 'lib/react_on_rails/server_rendering_pool/ruby_embedded_java_script.rb', line 223

def undefined_for_exec_js_logging(function_name)
  if ReactOnRails.configuration.trace
    "console.error('[React on Rails Rendering] #{function_name} is not defined for server rendering.');\n  " \
      "console.error(getStackTrace().join('\\n'));"
  else
    ""
  end
end