Class: ReactOnRails::ServerRenderingPool::RubyEmbeddedJavaScript

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

Overview

rubocop:disable Metrics/ClassLength

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 203

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

.create_js_context ⇒ Object 



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# File 'lib/react_on_rails/server_rendering_pool/ruby_embedded_java_script.rb', line 133

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

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

.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 113

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. rubocop:disable Metrics/CyclomaticComplexity, Metrics/AbcSize, Metrics/PerceivedComplexity



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# File 'lib/react_on_rails/server_rendering_pool/ruby_embedded_java_script.rb', line 50

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
    json_string = js_evaluator.eval_js(js_code, render_options)
  rescue StandardError => err
    msg = "      Error evaluating server bundle. Check your webpack configuration.\n      ===============================================================\n      Caught error:\n      \#{err.message}\n      ===============================================================\n    MSG\n\n    if err.message.include?(\"ReferenceError: self is not defined\")\n      msg << \"\\nError indicates that you may have code-splitting incorrectly enabled.\\n\"\n    end\n    raise ReactOnRails::Error, msg, err.backtrace\n  end\n  result = nil\n  begin\n    result = JSON.parse(json_string)\n  rescue JSON::ParserError => e\n    raise ReactOnRails::JsonParseError.new(parse_error: e, json: json_string)\n  end\n\n  if render_options.logging_on_server\n    console_script = result[\"consoleReplayScript\"]\n    console_script_lines = console_script.split(\"\\n\")\n    console_script_lines = console_script_lines[2..-2]\n    re = /console\\.(?:log|error)\\.apply\\(console, \\[\"\\[SERVER\\] (?<msg>.*)\"\\]\\);/\n    console_script_lines&.each do |line|\n      match = re.match(line)\n      Rails.logger.info { \"[react_on_rails] \#{match[:msg]}\" } if match\n    end\n  end\n  result\nend\n"

.execjs_timer_polyfills ⇒ Object 



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# File 'lib/react_on_rails/server_rendering_pool/ruby_embedded_java_script.rb', line 164

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

.read_bundle_js_code ⇒ Object 



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# File 'lib/react_on_rails/server_rendering_pool/ruby_embedded_java_script.rb', line 119

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}"
  raise ReactOnRails::Error, msg
end

.reset_pool ⇒ Object 



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# File 'lib/react_on_rails/server_rendering_pool/ruby_embedded_java_script.rb', line 11

def reset_pool
  options = {
    size: ReactOnRails.configuration.server_renderer_pool_size,
    timeout: ReactOnRails.configuration.server_renderer_timeout
  }
  @js_context_pool = ConnectionPool.new(options) { 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 19

def reset_pool_if_server_bundle_was_modified
  return unless ReactOnRails.configuration.development_mode

  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

rubocop:enable Metrics/CyclomaticComplexity, Metrics/AbcSize, Metrics/PerceivedComplexity



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# File 'lib/react_on_rails/server_rendering_pool/ruby_embedded_java_script.rb', line 95

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 = "    \#{'Z' * 80}\n    [react_on_rails] \#{msg}\n    JavaScript code used: \#{file_name}\n    \#{'Z' * 80}\n  MSG\n  if force\n    Rails.logger.error(msg)\n  else\n    Rails.logger.info(msg)\n  end\nend\n".strip_heredoc

.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 192

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