Bind aggregates over scoped tags to their subtree

CccConventions::TAG_SCOPES maps "update" and "pressemitteilung" to /updates
and "disclosure" to /disclosure. Page.aggregate applies the mapping, so an
aggregate over one of those tags is bounded by its subtree regardless of what
the shortcode says. Tags stay unrestricted; positions are publish-gated.

Both RSS actions call Page.aggregate rather than repeating its tag join.

Empty feeds no longer crash: Atom falls back to the current time for the
required <updated>, and the optional dc:date is omitted.

5 files changed, 23 insertions, 24 deletions

diff --git a/app/controllers/rss_controller.rb b/app/controllers/rss_controller.rb
index 655ccba4..c2149d90 100644
--- a/app/controllers/rss_controller.rb
+++ b/app/controllers/rss_controller.rb
@@ -1,19 +1,12 @@
 class RssController < ApplicationController
   
   before_action :get_host
-  
+
   def updates
     expires_in 31.minutes, :public => true
-    
     I18n.locale = I18n.default_locale
-  
-    @items = Page.heads
-      .joins("JOIN taggings ON taggings.taggable_id = pages.id
-            AND taggings.taggable_type = 'Page'
-            AND taggings.context = 'tags'")
-      .joins("JOIN tags ON tags.id = taggings.tag_id")
-      .where("LOWER(tags.name) = ?", "update")
-      .order("published_at DESC").limit(20)
+
+    @items = feed_items("update")
 
     respond_to do |format|
       format.xml {}
@@ -23,16 +16,10 @@ class RssController < ApplicationController
 
   def tag_updates
     expires_in 31.minutes, :public => true
-
     I18n.locale = I18n.default_locale
-    @tag  = params[:tag]
-    @items = Page.heads
-      .joins("JOIN taggings ON taggings.taggable_id = pages.id
-          AND taggings.taggable_type = 'Page'
-          AND taggings.context = 'tags'")
-      .joins("JOIN tags ON tags.id = taggings.tag_id")
-      .where("LOWER(tags.name) = ?", @tag.downcase)
-      .order("published_at DESC").limit(20)
+
+    @tag   = params[:tag]
+    @items = feed_items(@tag)
 
     respond_to do |format|
       format.xml {}
@@ -40,7 +27,14 @@ class RssController < ApplicationController
   end
 
   protected
-    
+
+    def feed_items tag
+      Page.aggregate(:tags => tag.to_s.downcase,
+                     :limit => 20,
+                     :order_by => "published_at",
+                     :order_direction => "DESC")
+    end
+
     def get_host
       @host = request.protocol + request.host_with_port
     end
diff --git a/app/helpers/content_helper.rb b/app/helpers/content_helper.rb
index 57f8c960..9d52c110 100644
--- a/app/helpers/content_helper.rb
+++ b/app/helpers/content_helper.rb
@@ -123,7 +123,7 @@ module ContentHelper
         sanitize(content, :attributes => cccms_attributes)
       end
 
-    rescue
+    rescue => e
       Rails.logger.error("aggregate shortcode failed on page #{@page&.id}: #{e.class}: #{e.message}")
       fallback = content.sub(/\[aggregate[^\]]*\]/, "")
       fallback = sanitize(fallback, :attributes => cccms_attributes)
diff --git a/app/models/page.rb b/app/models/page.rb
index cf003f74..a66527da 100644
--- a/app/models/page.rb
+++ b/app/models/page.rb
@@ -61,7 +61,7 @@ class Page < ApplicationRecord
     unless options[:tags].blank?
       tag_names = options[:tags].gsub(/\s/, ",").split(",").map(&:strip).map(&:downcase).uniq.reject(&:blank?)
 
-      unless tag_names.empty?
+    unless tag_names.empty?
         scope = scope
           .joins("JOIN taggings ON taggings.taggable_id = pages.id
                   AND taggings.taggable_type = 'Page'
@@ -71,6 +71,11 @@ class Page < ApplicationRecord
           .group("pages.id")
           .having("COUNT(DISTINCT tags.id) = ?", tag_names.length)
       end
+
+      CccConventions::TAG_SCOPES.values_at(*tag_names).compact.uniq.each do |root|
+        scope = scope.where("nodes.unique_name = ? OR nodes.unique_name LIKE ?",
+                            root, "#{root}/%")
+      end
     end
 
     if options[:node] && options[:children] == "direct"
diff --git a/app/views/rss/updates.rdf.builder b/app/views/rss/updates.rdf.builder
index b02d34ff..b4fecdb0 100644
--- a/app/views/rss/updates.rdf.builder
+++ b/app/views/rss/updates.rdf.builder
@@ -6,7 +6,7 @@ xml.tag!("rdf:RDF", "xmlns:rdf" => "http://www.w3.org/1999/02/22-rdf-syntax-ns#"
     xml.title("Chaos Computer Club: Updates")
     xml.link("https://www.ccc.de")
     xml.description("Kabelsalat ist gesund.")
-    xml.tag!("dc:date", @items.first.published_at.xmlschema)
+    xml.tag!("dc:date", @items.first&.published_at&.xmlschema) if @items.any?
   end
 
   xml.image( "rdf:about" => "https://www.ccc.de/images/chaosknoten.gif") do
diff --git a/app/views/rss/updates.xml.builder b/app/views/rss/updates.xml.builder
index 27845c4c..f261de89 100644
--- a/app/views/rss/updates.xml.builder
+++ b/app/views/rss/updates.xml.builder
@@ -4,7 +4,7 @@ xml.feed(:xmlns => "http://www.w3.org/2005/Atom", "xml:base" => @host) do
   xml.title("Chaos Computer Club Updates")
   xml.link(:href => "https://www.ccc.de/")
   xml.link(:rel => "self", :href => "#{@host}/rss/updates.xml")
-  xml.updated(@items.first.published_at.xmlschema)
+  xml.updated((@items.first&.published_at || Time.now).xmlschema)
   xml.author do
     xml.name("Chaos Computer Club e.V.")
   end