Add Conference Dynamic Variable Substitution in Markdown

app/controllers/conferences_controller.rb

@@ -28,7 +28,13 @@ def show
 
     @splashpage = @conference.splashpage
 
-    redirect_to admin_conference_splashpage_path(@conference.short_title) && return unless @splashpage.present?
+    # NOTE: do not write `redirect_to(...) && return unless ...` — Ruby parses that as
+    # `redirect_to((...) && return) unless ...`, which evaluates `return` before `redirect_to`
+    # when the splashpage is missing, skipping the redirect and rendering show with a nil splashpage.
+    unless @splashpage.present?
+      redirect_to admin_conference_splashpage_path(@conference.short_title)
+      return
+    end
 
     # User messages at the top of the page.
     @unpaid_tickets = current_user_has_unpaid_tickets?

app/helpers/application_helper.rb

@@ -5,6 +5,7 @@
 # TODO-SNAPCON: Refactor this module. Move chunks to a dates_help, some events_helper
 module ApplicationHelper
   include Pagy::Frontend
+  include ConferenceTemplateHelper
   # Returns a string build from the start and end date of the given conference.
   #
   # If the conference is only one day long

app/helpers/conference_template_helper.rb

@@ -0,0 +1,8 @@
+# frozen_string_literal: true
+
+module ConferenceTemplateHelper
+  def conference_template_markdown(text, conference, escape_html: false)
+    interpolated = ConferenceMarkdownTemplate.interpolate(text, conference)
+    markdown(interpolated, escape_html)
+  end
+end

app/services/conference_markdown_template.rb

@@ -0,0 +1,112 @@
+# frozen_string_literal: true
+
+# Interpolates `{token}` placeholders in conference-facing Markdown fields.
+#
+# This intentionally mirrors the `{key}` substitution style used by
+# `EmailTemplateParser`, but only exposes conference-scoped values (no user).
+class ConferenceMarkdownTemplate
+  KNOWN_TEMPLATE_KEYS = %w[
+    conference conference_short start_date end_date timezone
+    cfp_start_date cfp_end_date
+    venue venue_address
+    registration_start_date registration_end_date
+    num_public_event_types
+  ].freeze
+
+  def self.interpolate(text, conference)
+    return '' if text.blank?
+    return text if conference.blank?
+
+    values = build_values(conference)
+    substituted = EmailTemplateParser.parse_template(text, values)
+
+    # Aliases / friendlier names for issue descriptions
+    alias_map = {
+      'conference_name' => 'conference',
+      'short_name' => 'conference_short',
+      'cfp_deadline' => 'cfp_end_date'
+    }
+
+    alias_map.each do |from, to|
+      raw = values[to]
+      replacement =
+        if raw.is_a?(Date)
+          raw.strftime('%Y-%m-%d')
+        else
+          raw.presence || ''
+        end
+
+      substituted = substituted.gsub("{#{from}}", replacement)
+    end
+
+    # `EmailTemplateParser.parse_template` skips blank values, which leaves tokens
+    # like `{cfp_end_date}` in place when optional sections are empty. For
+    # conference-facing Markdown we prefer removing those placeholders entirely.
+    substituted = substitute_known_keys(substituted, values)
+
+    substituted
+  end
+
+  def self.substitute_known_keys(text, values)
+    return text if text.blank?
+
+    KNOWN_TEMPLATE_KEYS.each do |key|
+      next unless text.include?("{#{key}}")
+
+      raw = values[key]
+      replacement =
+        if raw.is_a?(Date)
+          raw.strftime('%Y-%m-%d')
+        else
+          raw.presence || ''
+        end
+
+      text = text.gsub("{#{key}}", replacement)
+    end
+
+    text
+  end
+
+  def self.build_values(conference)
+    h = {
+      'conference' => conference.title,
+      'conference_short' => conference.short_title,
+      'start_date' => conference.start_date,
+      'end_date' => conference.end_date,
+      'timezone' => conference.timezone
+    }
+
+    events_cfp = conference.program&.cfps&.find_by(cfp_type: 'events')
+    if events_cfp
+      h['cfp_start_date'] = events_cfp.start_date
+      h['cfp_end_date'] = events_cfp.end_date
+    else
+      h['cfp_start_date'] = ''
+      h['cfp_end_date'] = ''
+    end
+
+    if conference.venue
+      h['venue'] = conference.venue.name
+      h['venue_address'] = conference.venue.address
+    else
+      h['venue'] = ''
+      h['venue_address'] = ''
+    end
+
+    if conference.registration_period
+      h['registration_start_date'] = conference.registration_period.start_date
+      h['registration_end_date'] = conference.registration_period.end_date
+    else
+      h['registration_start_date'] = ''
+      h['registration_end_date'] = ''
+    end
+
+    if conference.program
+      h['num_public_event_types'] = conference.program.event_types.available_for_public.count.to_s
+    else
+      h['num_public_event_types'] = '0'
+    end
+
+    h
+  end
+end

app/views/admin/conferences/_form_fields.html.haml

@@ -23,10 +23,66 @@
     = f.label :description
     = f.text_area :description, rows: 5, data: { provide: 'markdown' }, class: 'form-control'
     .help-block= markdown_hint('Splash page content')
+    %a.btn.btn-link.control_label.template_help_link{ 'data-name' => 'conference_description_template_help' } Show available template variables
+    .template-help{ id: 'conference_description_template_help' }
+      %p
+        You can embed placeholders like
+        %code {conference}
+        which will be replaced on the public splash page using the current conference data.
+      %ul
+        %li
+          %code {conference}
+          (alias:
+          %code {conference_name}
+          ) — conference title
+        %li
+          %code {conference_short}
+          (alias:
+          %code {short_name}
+          ) — conference short title
+        %li
+          %code {start_date}
+          /
+          %code {end_date}
+          — conference dates (formatted as YYYY-MM-DD)
+        %li
+          %code {cfp_start_date}
+          /
+          %code {cfp_end_date}
+          — CFP for events dates (if configured)
+        %li
+          %code {cfp_deadline}
+          — alias for
+          %code {cfp_end_date}
+        %li
+          %code {venue}
+          — venue name (if configured)
+        %li
+          %code {venue_address}
+          — venue address (if configured)
+        %li
+          %code {registration_start_date}
+          /
+          %code {registration_end_date}
+          — registration period dates (if configured)
+        %li
+          %code {num_public_event_types}
+          — count of event types that allow public submission
+        %li
+          %code {timezone}
+          — conference timezone string
   .form-group
     = f.label :registered_attendees_message, 'Message for Registered Attendees'
     = f.text_area :registered_attendees_message, rows: 5, data: { provide: 'markdown' }, class: 'form-control'
     .help-block= markdown_hint('Splash page content')
+    %a.btn.btn-link.control_label.template_help_link{ 'data-name' => 'conference_registered_attendees_template_help' } Show available template variables
+    .template-help{ id: 'conference_registered_attendees_template_help' }
+      %p
+        Same placeholders as the conference description (for example
+        %code {conference}
+        and
+        %code {start_date}
+        ).
   .form-group
     = f.color_field :color, size: 6, class: 'form-control'
     %span.help-block

app/views/conferences/_about_and_happening_now.haml

@@ -9,8 +9,8 @@
 = content_for :about do
   #about
     -if @user_registered && conference.registered_attendees_message.present?
-      = markdown(conference.registered_attendees_message, false)
-    = markdown(conference.description, false)
+      = conference_template_markdown(conference.registered_attendees_message, conference, escape_html: false)
+    = conference_template_markdown(conference.description, conference, escape_html: false)
 
 %section#about-and-happening-now
   .container

app/views/conferences/_header.haml

@@ -1,11 +1,11 @@
-- cache [conference, venue, '#splash#header'] do
-  #banner{ style: ("background-image: url(#{splashpage.banner_photo_url})" if splashpage.banner_photo_url) }
+- cache [conference, venue, splashpage, '#splash#header'] do
+  #banner{ style: ("background-image: url(#{splashpage.banner_photo_url})" if splashpage&.banner_photo_url) }
     .container
       .row
-        - picture_present = splashpage.banner_photo? || conference.picture?
+        - picture_present = splashpage&.banner_photo? || conference.picture?
         .col-md-6.col-md-offset-3{ id: (picture_present ? "header-image" : "header-no-image") }
           .row
-            - if conference.picture? && !splashpage.banner_photo?
+            - if conference.picture? && !splashpage&.banner_photo?
               .col-md-4
                 = image_tag(conference.picture_url,
                   class: 'img-responsive img-center',

spec/controllers/conferences_controller_spec.rb

@@ -27,6 +27,17 @@
       end
     end
 
+    context 'when the conference has no splashpage' do
+      let(:conference_without_splash) { create(:conference) }
+      let!(:organizer) { create(:organizer, resource: conference_without_splash) }
+
+      it 'redirects organizers to admin splashpage setup (regression: redirect must not be skipped by Ruby parsing)' do
+        sign_in organizer
+        get :show, params: { id: conference_without_splash.short_title }
+        expect(response).to redirect_to(admin_conference_splashpage_path(conference_without_splash.short_title))
+      end
+    end
+
     context 'accessing conference via custom domain' do
       before do
         conference.update_attribute(:custom_domain, 'lvh.me')

spec/services/conference_markdown_template_spec.rb

@@ -0,0 +1,61 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe ConferenceMarkdownTemplate do
+  describe '.interpolate' do
+    it 'returns empty string for blank text' do
+      conference = build(:conference)
+      expect(described_class.interpolate('', conference)).to eq('')
+      expect(described_class.interpolate(nil, conference)).to eq('')
+    end
+
+    it 'returns original text when conference is blank' do
+      expect(described_class.interpolate('{conference}', nil)).to eq('{conference}')
+    end
+
+    it 'substitutes conference values, CFP (events), venue, registration, and public event type count' do
+      conference = create(:full_conference)
+      conference.program.event_types.first.update!(enable_public_submission: false)
+      create(:event_type, program: conference.program, title: 'Poster', enable_public_submission: true)
+
+      events_cfp = conference.program.cfps.find_by!(cfp_type: 'events')
+      template = <<~TEXT.squish
+        {conference} / {conference_short}
+        {conference_name} / {short_name}
+        {start_date}–{end_date} {timezone}
+        CFP {cfp_start_date}–{cfp_end_date} deadline {cfp_deadline}
+        {venue} — {venue_address}
+        Reg {registration_start_date}–{registration_end_date}
+        Public types: {num_public_event_types}
+      TEXT
+
+      result = described_class.interpolate(template, conference)
+
+      expect(result).to include(conference.title)
+      expect(result).to include(conference.short_title)
+      expect(result).to include("#{conference.start_date.strftime('%Y-%m-%d')}–#{conference.end_date.strftime('%Y-%m-%d')}")
+      expect(result).to include(conference.timezone)
+      expect(result).to include("#{events_cfp.start_date.strftime('%Y-%m-%d')}–#{events_cfp.end_date.strftime('%Y-%m-%d')}")
+      expect(result).to include(conference.venue.name)
+      expect(result).to include(conference.venue.address)
+      expect(result).to include(
+        "#{conference.registration_period.start_date.strftime('%Y-%m-%d')}–#{conference.registration_period.end_date.strftime('%Y-%m-%d')}"
+      )
+      expect(result).to include('Public types: 2')
+    end
+
+    it 'uses empty strings for optional sections when not configured (but still counts default public event types)' do
+      conference = create(:conference)
+      conference.program.cfps.destroy_all
+      conference.venue&.destroy
+      conference.registration_period&.destroy
+      conference.reload
+
+      template = 'CFP:{cfp_end_date}|Venue:{venue}|Reg:{registration_end_date}|Types:{num_public_event_types}'
+      result = described_class.interpolate(template, conference)
+
+      expect(result).to eq('CFP:|Venue:|Reg:|Types:2')
+    end
+  end
+end