module ReactOnRails::Helper

Constants

COMPONENT_HTML_KEY

Public Instance Methods

json_safe_and_pretty(hash_or_string) click to toggle source
# File lib/react_on_rails/helper.rb, line 244
def json_safe_and_pretty(hash_or_string)
  return "{}" if hash_or_string.nil?

  unless hash_or_string.is_a?(String) || hash_or_string.is_a?(Hash)
    raise ReactOnRails::Error, "#{__method__} only accepts String or Hash as argument " \
                               "(#{hash_or_string.class} given)."
  end

  json_value = hash_or_string.is_a?(String) ? hash_or_string : hash_or_string.to_json

  ReactOnRails::JsonOutput.escape(json_value)
end
load_pack_for_generated_component(react_component_name, render_options) click to toggle source
# File lib/react_on_rails/helper.rb, line 316
def load_pack_for_generated_component(react_component_name, render_options)
  return unless render_options.auto_load_bundle

  ReactOnRails::PackerUtils.raise_nested_entries_disabled unless ReactOnRails::PackerUtils.nested_entries?
  if Rails.env.development?
    is_component_pack_present = File.exist?(generated_components_pack_path(react_component_name))
    raise_missing_autoloaded_bundle(react_component_name) unless is_component_pack_present
  end
  append_javascript_pack_tag("generated/#{react_component_name}",
                             defer: ReactOnRails.configuration.defer_generated_component_packs)
  append_stylesheet_pack_tag("generated/#{react_component_name}")
end
rails_context(server_side: true) click to toggle source

This is the definitive list of the default values used for the rails_context, which is the second parameter passed to both component and store Render-Functions. This method can be called from views and from the controller, as ‘helpers.rails_context`

rubocop:disable Metrics/AbcSize, Metrics/CyclomaticComplexity

# File lib/react_on_rails/helper.rb, line 262
def rails_context(server_side: true)
  # ALERT: Keep in sync with node_package/src/types/index.ts for the properties of RailsContext
  @rails_context ||= begin
    result = {
      railsEnv: Rails.env,
      inMailer: in_mailer?,
      # Locale settings
      i18nLocale: I18n.locale,
      i18nDefaultLocale: I18n.default_locale,
      rorVersion: ReactOnRails::VERSION,
      # TODO: v13 just use the version if existing
      rorPro: ReactOnRails::Utils.react_on_rails_pro?
    }
    if ReactOnRails::Utils.react_on_rails_pro?
      result[:rorProVersion] = ReactOnRails::Utils.react_on_rails_pro_version
    end

    if defined?(request) && request.present?
      # Check for encoding of the request's original_url and try to force-encoding the
      # URLs as UTF-8. This situation can occur in browsers that do not encode the
      # entire URL as UTF-8 already, mostly on the Windows platform (IE11 and lower).
      original_url_normalized = request.original_url
      if original_url_normalized.encoding == Encoding::BINARY
        original_url_normalized = original_url_normalized.force_encoding(Encoding::ISO_8859_1)
                                                         .encode(Encoding::UTF_8)
      end

      # Using Addressable instead of standard URI to better deal with
      # non-ASCII characters (see https://github.com/shakacode/react_on_rails/pull/405)
      uri = Addressable::URI.parse(original_url_normalized)
      # uri = Addressable::URI.parse("http://foo.com:3000/posts?id=30&limit=5#time=1305298413")

      result.merge!(
        # URL settings
        href: uri.to_s,
        location: "#{uri.path}#{uri.query.present? ? "?#{uri.query}" : ''}",
        scheme: uri.scheme, # http
        host: uri.host, # foo.com
        port: uri.port,
        pathname: uri.path, # /posts
        search: uri.query, # id=30&limit=5
        httpAcceptLanguage: request.env["HTTP_ACCEPT_LANGUAGE"]
      )
    end
    if ReactOnRails.configuration.rendering_extension
      custom_context = ReactOnRails.configuration.rendering_extension.custom_context(self)
      result.merge!(custom_context) if custom_context
    end
    result
  end

  @rails_context.merge(serverSide: server_side)
end
react_component(component_name, options = {}) click to toggle source

react_component_name: can be a React function or class component or a “Render-Function”. “Render-Functions” differ from a React function in that they take two parameters, the

props and the railsContext, like this:

let MyReactComponentApp = (props, railsContext) => <MyReactComponent {...props}/>;

Alternately, you can define the Render-Function with an additional property
`.renderFunction = true`:

let MyReactComponentApp = (props) => <MyReactComponent {...props}/>;
MyReactComponent.renderFunction = true;

Exposing the react_component_name is necessary to both a plain ReactComponent as well as
  a generator:
See README.md for how to "register" your react components.
See spec/dummy/client/app/packs/server-bundle.js and
  spec/dummy/client/app/packs/client-bundle.js for examples of this.

options:

props: Ruby Hash or JSON string which contains the properties to pass to the react object. Do
   not pass any props if you are separately initializing the store by the `redux_store` helper.
prerender: <true/false> set to false when debugging!
id: You can optionally set the id, or else a unique one is automatically generated.
html_options: You can set other html attributes that will go on this component
trace: <true/false> set to true to print additional debugging information in the browser
       default is true for development, off otherwise
replay_console: <true/false> Default is true. False will disable echoing server rendering
                logs to browser. While this can make troubleshooting server rendering difficult,
                so long as you have the default configuration of logging_on_server set to
                true, you'll still see the errors on the server.
raise_on_prerender_error: <true/false> Default to false. True will raise exception on server
   if the JS code throws

Any other options are passed to the content tag, including the id. random_dom_id can be set to override the default from the config/initializers. That’s only used if you have multiple instance of the same component on the Rails view.

# File lib/react_on_rails/helper.rb, line 56
    def react_component(component_name, options = {})
      internal_result = internal_react_component(component_name, options)
      server_rendered_html = internal_result[:result]["html"]
      console_script = internal_result[:result]["consoleReplayScript"]
      render_options = internal_result[:render_options]

      case server_rendered_html
      when String
        build_react_component_result_for_server_rendered_string(
          server_rendered_html: server_rendered_html,
          component_specification_tag: internal_result[:tag],
          console_script: console_script,
          render_options: render_options
        )
      when Hash
        msg = <<~MSG
          Use react_component_hash (not react_component) to return a Hash to your ruby view code. See
          https://github.com/shakacode/react_on_rails/blob/master/spec/dummy/client/app/startup/ReactHelmetServerApp.jsx
          for an example of the necessary javascript configuration.
        MSG
        raise ReactOnRails::Error, msg
      else
        class_name = server_rendered_html.class.name
        msg = <<~MSG
          ReactOnRails: server_rendered_html is expected to be a String or Hash for #{component_name}.
          Type is #{class_name}
          Value:
          #{server_rendered_html}

          If you're trying to use a Render-Function to return a Hash to your ruby view code, then use
          react_component_hash instead of react_component and see
          https://github.com/shakacode/react_on_rails/blob/master/spec/dummy/client/app/startup/ReactHelmetServerApp.jsx
          for an example of the JavaScript code.
        MSG
        raise ReactOnRails::Error, msg
      end
    end
react_component_hash(component_name, options = {}) click to toggle source

react_component_hash is used to return multiple HTML strings for server rendering, such as for adding meta-tags to a page. It is exactly like react_component except for the following:

  1. prerender: true is automatically added, as this method doesn’t make sense for client only rendering.

  2. Your JavaScript Render-Function for server rendering must return an Object rather than a React component.

  3. Your view code must expect an object and not a string.

Here is an example of the view code:

<% react_helmet_app = react_component_hash("ReactHelmetApp", prerender: true,
                                           props: { helloWorldData: { name: "Mr. Server Side Rendering"}},
                                           id: "react-helmet-0", trace: true) %>
<% content_for :title do %>
  <%= react_helmet_app['title'] %>
<% end %>
<%= react_helmet_app["componentHtml"] %>
# File lib/react_on_rails/helper.rb, line 111
    def react_component_hash(component_name, options = {})
      options[:prerender] = true
      internal_result = internal_react_component(component_name, options)
      server_rendered_html = internal_result[:result]["html"]
      console_script = internal_result[:result]["consoleReplayScript"]
      render_options = internal_result[:render_options]

      if server_rendered_html.is_a?(String) && internal_result[:result]["hasErrors"]
        server_rendered_html = { COMPONENT_HTML_KEY => internal_result[:result]["html"] }
      end

      if server_rendered_html.is_a?(Hash)
        build_react_component_result_for_server_rendered_hash(
          server_rendered_html: server_rendered_html,
          component_specification_tag: internal_result[:tag],
          console_script: console_script,
          render_options: render_options
        )
      else
        msg = <<~MSG
          Render-Function used by react_component_hash for #{component_name} is expected to return
          an Object. See https://github.com/shakacode/react_on_rails/blob/master/spec/dummy/client/app/startup/ReactHelmetServerApp.jsx
          for an example of the JavaScript code.
          Note, your Render-Function must either take 2 params or have the property
          `.renderFunction = true` added to it to distinguish it from a React Function Component.
        MSG
        raise ReactOnRails::Error, msg
      end
    end
redux_store(store_name, props: {}, defer: false) click to toggle source

Separate initialization of store from react_component allows multiple react_component calls to use the same Redux store.

NOTE: This technique not recommended as it prevents dynamic code splitting for performance. Instead, you should use the standard react_component view helper.

store_name: name of the store, corresponding to your call to ReactOnRails.registerStores in your

JavaScript code.

props: Ruby Hash or JSON string which contains the properties to pass to the redux store. Options

defer: false -- pass as true if you wish to render this below your component.
# File lib/react_on_rails/helper.rb, line 152
def redux_store(store_name, props: {}, defer: false)
  redux_store_data = { store_name: store_name,
                       props: props }
  if defer
    @registered_stores_defer_render ||= []
    @registered_stores_defer_render << redux_store_data
    "YOU SHOULD NOT SEE THIS ON YOUR VIEW -- Uses as a code block, like <% redux_store %> " \
      "and not <%= redux store %>"
  else
    @registered_stores ||= []
    @registered_stores << redux_store_data
    result = render_redux_store_data(redux_store_data)
    prepend_render_rails_context(result)
  end
end
redux_store_hydration_data() click to toggle source

Place this view helper (no parameters) at the end of your shared layout. This tell ReactOnRails where to client render the redux store hydration data. Since we’re going to be setting up the stores in the controllers, we need to know where on the view to put the client side rendering of this hydration data, which is a hidden div with a matching class that contains a data props.

# File lib/react_on_rails/helper.rb, line 173
def redux_store_hydration_data
  return if @registered_stores_defer_render.blank?

  @registered_stores_defer_render.reduce(+"") do |accum, redux_store_data|
    accum << render_redux_store_data(redux_store_data)
  end.html_safe
end
sanitized_props_string(props) click to toggle source
# File lib/react_on_rails/helper.rb, line 181
def sanitized_props_string(props)
  ReactOnRails::JsonOutput.escape(props.is_a?(String) ? props : props.to_json)
end
server_render_js(js_expression, options = {}) click to toggle source

Helper method to take javascript expression and returns the output from evaluating it. If you have more than one line that needs to be executed, wrap it in an IIFE. JS exceptions are caught and console messages are handled properly. Options include:{ prerender:, trace:, raise_on_prerender_error:, throw_js_errors: }

# File lib/react_on_rails/helper.rb, line 189
    def server_render_js(js_expression, options = {})
      render_options = ReactOnRails::ReactComponent::RenderOptions
                       .new(react_component_name: "generic-js", options: options)

      js_code = <<-JS.strip_heredoc
      (function() {
        var htmlResult = '';
        var consoleReplayScript = '';
        var hasErrors = false;
        var renderingError = null;
        var renderingErrorObject = {};

        try {
          htmlResult =
            (function() {
              return #{js_expression};
            })();
        } catch(e) {
          renderingError = e;
          if (#{render_options.throw_js_errors}) {
            throw e;
          }
          htmlResult = ReactOnRails.handleError({e: e, name: null,
            jsCode: '#{escape_javascript(js_expression)}', serverSide: true});
          hasErrors = true;
          renderingErrorObject = {
            message: renderingError.message,
            stack: renderingError.stack,
          }
        }

        consoleReplayScript = ReactOnRails.buildConsoleReplay();

        return JSON.stringify({
            html: htmlResult,
            consoleReplayScript: consoleReplayScript,
            hasErrors: hasErrors,
            renderingError: renderingErrorObject
        });

      })()
      JS

      result = ReactOnRails::ServerRenderingPool
               .server_render_js_with_console_logging(js_code, render_options)

      html = result["html"]
      console_log_script = result["consoleLogScript"]
      raw("#{html}#{render_options.replay_console ? console_log_script : ''}")
    rescue ExecJS::ProgramError => err
      raise ReactOnRails::PrerenderError.new(component_name: "N/A (server_render_js called)",
                                             err: err,
                                             js_code: js_code)
    end

Private Instance Methods

build_react_component_result_for_server_rendered_hash( server_rendered_html: required("server_rendered_html"), component_specification_tag: required("component_specification_tag"), console_script: required("console_script"), render_options: required("render_options") ) click to toggle source
# File lib/react_on_rails/helper.rb, line 364
def build_react_component_result_for_server_rendered_hash(
  server_rendered_html: required("server_rendered_html"),
  component_specification_tag: required("component_specification_tag"),
  console_script: required("console_script"),
  render_options: required("render_options")
)
  content_tag_options = render_options.html_options
  content_tag_options[:id] = render_options.dom_id

  unless server_rendered_html[COMPONENT_HTML_KEY]
    raise ReactOnRails::Error, "server_rendered_html hash expected to contain \"#{COMPONENT_HTML_KEY}\" key."
  end

  rendered_output = content_tag(:div,
                                server_rendered_html[COMPONENT_HTML_KEY].html_safe,
                                content_tag_options)

  result_console_script = render_options.replay_console ? console_script : ""
  result = compose_react_component_html_with_spec_and_console(
    component_specification_tag, rendered_output, result_console_script
  )

  # Other HTML strings need to be marked as html_safe too:
  server_rendered_hash_except_component = server_rendered_html.except(COMPONENT_HTML_KEY)
  server_rendered_hash_except_component.each do |key, html_string|
    server_rendered_hash_except_component[key] = html_string.html_safe
  end

  result_with_rails_context = prepend_render_rails_context(result)
  { COMPONENT_HTML_KEY => result_with_rails_context }.merge(
    server_rendered_hash_except_component
  )
end
build_react_component_result_for_server_rendered_string( server_rendered_html: required("server_rendered_html"), component_specification_tag: required("component_specification_tag"), console_script: required("console_script"), render_options: required("render_options") ) click to toggle source
# File lib/react_on_rails/helper.rb, line 337
def build_react_component_result_for_server_rendered_string(
  server_rendered_html: required("server_rendered_html"),
  component_specification_tag: required("component_specification_tag"),
  console_script: required("console_script"),
  render_options: required("render_options")
)
  content_tag_options = render_options.html_options
  if content_tag_options.key?(:tag)
    content_tag_options_html_tag = content_tag_options[:tag]
    content_tag_options.delete(:tag)
  else
    content_tag_options_html_tag = "div"
  end
  content_tag_options[:id] = render_options.dom_id

  rendered_output = content_tag(content_tag_options_html_tag.to_sym,
                                server_rendered_html.html_safe,
                                content_tag_options)

  result_console_script = render_options.replay_console ? console_script : ""
  result = compose_react_component_html_with_spec_and_console(
    component_specification_tag, rendered_output, result_console_script
  )

  prepend_render_rails_context(result)
end
compose_react_component_html_with_spec_and_console(component_specification_tag, rendered_output, console_script) click to toggle source
# File lib/react_on_rails/helper.rb, line 398
    def compose_react_component_html_with_spec_and_console(component_specification_tag, rendered_output, console_script)
      # IMPORTANT: Ensure that we mark string as html_safe to avoid escaping.
      <<~HTML.html_safe
        #{rendered_output}
              #{component_specification_tag}
              #{console_script}
      HTML
    end
generated_components_pack_path(component_name) click to toggle source

rubocop:enable Metrics/AbcSize, Metrics/CyclomaticComplexity

# File lib/react_on_rails/helper.rb, line 333
def generated_components_pack_path(component_name)
  "#{ReactOnRails::PackerUtils.packer_source_entry_path}/generated/#{component_name}.js"
end
in_mailer?() click to toggle source
# File lib/react_on_rails/helper.rb, line 563
def in_mailer?
  return false unless defined?(controller)
  return false unless defined?(ActionMailer::Base)

  controller.is_a?(ActionMailer::Base)
end
initialize_redux_stores() click to toggle source
# File lib/react_on_rails/helper.rb, line 536
    def initialize_redux_stores
      result = +<<-JS
      ReactOnRails.clearHydratedStores();
      JS

      return result unless @registered_stores.present? || @registered_stores_defer_render.present?

      declarations = +"var reduxProps, store, storeGenerator;\n"
      all_stores = (@registered_stores || []) + (@registered_stores_defer_render || [])

      result << all_stores.each_with_object(declarations) do |redux_store_data, memo|
        store_name = redux_store_data[:store_name]
        props = props_string(redux_store_data[:props])
        memo << <<-JS.strip_heredoc
        reduxProps = #{props};
        storeGenerator = ReactOnRails.getStoreGenerator('#{store_name}');
        store = storeGenerator(reduxProps, railsContext);
        ReactOnRails.setStore('#{store_name}', store);
        JS
      end
      result
    end
internal_react_component(react_component_name, options = {}) click to toggle source
# File lib/react_on_rails/helper.rb, line 423
    def internal_react_component(react_component_name, options = {})
      # Create the JavaScript and HTML to allow either client or server rendering of the
      # react_component.
      #
      # Create the JavaScript setup of the global to initialize the client rendering
      # (re-hydrate the data). This enables react rendered on the client to see that the
      # server has already rendered the HTML.

      render_options = ReactOnRails::ReactComponent::RenderOptions.new(react_component_name: react_component_name,
                                                                       options: options)

      # Setup the page_loaded_js, which is the same regardless of prerendering or not!
      # The reason is that React is smart about not doing extra work if the server rendering did its job.
      component_specification_tag = content_tag(:script,
                                                json_safe_and_pretty(render_options.client_props).html_safe,
                                                type: "application/json",
                                                class: "js-react-on-rails-component",
                                                "data-component-name" => render_options.react_component_name,
                                                "data-trace" => (render_options.trace ? true : nil),
                                                "data-dom-id" => render_options.dom_id)

      if render_options.force_load
        component_specification_tag.concat(
          content_tag(:script, %(
ReactOnRails.reactOnRailsComponentLoaded('#{render_options.dom_id}');
          ).html_safe)
        )
      end

      load_pack_for_generated_component(react_component_name, render_options)
      # Create the HTML rendering part
      result = server_rendered_react_component(render_options)

      {
        render_options: render_options,
        tag: component_specification_tag,
        result: result
      }
    end
prepend_render_rails_context(render_value) click to toggle source

prepend the rails_context if not yet applied

# File lib/react_on_rails/helper.rb, line 408
def prepend_render_rails_context(render_value)
  return render_value if @rendered_rails_context

  data = rails_context(server_side: false)

  @rendered_rails_context = true

  rails_context_content = content_tag(:script,
                                      json_safe_and_pretty(data).html_safe,
                                      type: "application/json",
                                      id: "js-react-on-rails-context")

  "#{rails_context_content}\n#{render_value}".html_safe
end
props_string(props) click to toggle source
# File lib/react_on_rails/helper.rb, line 472
def props_string(props)
  props.is_a?(String) ? props : props.to_json
end
raise_missing_autoloaded_bundle(react_component_name) click to toggle source
# File lib/react_on_rails/helper.rb, line 576
    def raise_missing_autoloaded_bundle(react_component_name)
      msg = <<~MSG
        **ERROR** ReactOnRails: Component "#{react_component_name}" is configured as "auto_load_bundle: true"
        but the generated component entrypoint, which should have been at #{generated_components_pack_path(react_component_name)},
        is missing. You might want to check that this component is in a directory named "#{ReactOnRails.configuration.components_subdirectory}"
        & that "bundle exec rake react_on_rails:generate_packs" has been run.
      MSG

      raise ReactOnRails::Error, msg
    end
render_redux_store_data(redux_store_data) click to toggle source
# File lib/react_on_rails/helper.rb, line 463
def render_redux_store_data(redux_store_data)
  result = content_tag(:script,
                       json_safe_and_pretty(redux_store_data[:props]).html_safe,
                       type: "application/json",
                       "data-js-react-on-rails-store" => redux_store_data[:store_name].html_safe)

  prepend_render_rails_context(result)
end
replay_console_option(val) click to toggle source
# File lib/react_on_rails/helper.rb, line 559
def replay_console_option(val)
  val.nil? ? ReactOnRails.configuration.replay_console : val
end
server_rendered_react_component(render_options) click to toggle source

Returns object with values that are NOT html_safe!

# File lib/react_on_rails/helper.rb, line 477
def server_rendered_react_component(render_options)
  return { "html" => "", "consoleReplayScript" => "" } unless render_options.prerender

  react_component_name = render_options.react_component_name
  props = render_options.props

  # On server `location` option is added (`location = request.fullpath`)
  # React Router needs this to match the current route

  # Make sure that we use up-to-date bundle file used for server rendering, which is defined
  # by config file value for config.server_bundle_js_file
  ReactOnRails::ServerRenderingPool.reset_pool_if_server_bundle_was_modified

  # Since this code is not inserted on a web page, we don't need to escape props
  #
  # However, as JSON (returned from `props_string(props)`) isn't JavaScript,
  # but we want treat it as such, we need to compensate for the difference.
  #
  # \u2028 and \u2029 are valid characters in strings in JSON, but are treated
  # as newline separators in JavaScript. As no newlines are allowed in
  # strings in JavaScript, this causes an exception.
  #
  # We fix this by replacing these unicode characters with their escaped versions.
  # This should be safe, as the only place they can appear is in strings anyway.
  #
  # Read more here: http://timelessrepo.com/json-isnt-a-javascript-subset

  js_code = ReactOnRails::ServerRenderingJsCode.server_rendering_component_js_code(
    props_string: props_string(props).gsub("\u2028", '\u2028').gsub("\u2029", '\u2029'),
    rails_context: rails_context(server_side: true).to_json,
    redux_stores: initialize_redux_stores,
    react_component_name: react_component_name,
    render_options: render_options
  )

  begin
    result = ReactOnRails::ServerRenderingPool.server_render_js_with_console_logging(js_code, render_options)
  rescue StandardError => err
    # This error came from the renderer
    raise ReactOnRails::PrerenderError.new(component_name: react_component_name,
                                           # Sanitize as this might be browser logged
                                           props: sanitized_props_string(props),
                                           err: err,
                                           js_code: js_code)
  end

  if result["hasErrors"] && render_options.raise_on_prerender_error
    # We caught this exception on our backtrace handler
    raise ReactOnRails::PrerenderError.new(component_name: react_component_name,
                                           # Sanitize as this might be browser logged
                                           props: sanitized_props_string(props),
                                           err: nil,
                                           js_code: js_code,
                                           console_messages: result["consoleReplayScript"])

  end
  result
end