patches.rb in locomotive_cms-2.5.5

- old
+ new
@@ -20,11 +20,55 @@
       attrs
     end
   end
 
   class Criteria
+    def without_sorting
+      clone.tap { |crit| crit.options.delete(:sort) }
+    end
+
+    # http://code.dblock.org/paging-and-iterating-over-large-mongo-collections
+    def each_by(by, &block)
+      idx = total = 0
+      set_limit = options[:limit]
+      while ((results = ordered_clone.limit(by).skip(idx)) && results.any?)
+        results.each do |result|
+          return self if set_limit and set_limit >= total
+          total += 1
+          yield result
+        end
+        idx += by
+      end
+      self
+    end
+
+    # Optimized version of the max aggregate method.
+    # It works efficiently only if the field is part of a MongoDB index.
+    # more here: http://stackoverflow.com/questions/4762980/getting-the-highest-value-of-a-column-in-mongodb
+    def indexed_max(field)
+      _criteria = criteria.order_by(field.to_sym.desc).only(field.to_sym)
+      selector  = _criteria.send(:selector_with_type_selection)
+      fields    = _criteria.options[:fields]
+      sort      = _criteria.options[:sort]
+
+      document = collection.find(selector).select(fields).sort(sort).limit(1).first
+      document ? document[field.to_s].to_i : nil
+    end
+
     def to_liquid
       Locomotive::Liquid::Drops::ProxyCollection.new(self)
+    end
+
+    private
+
+    def ordered_clone
+      options[:sort] ? clone : clone.asc(:_id)
+    end
+  end
+
+  module Finders
+    def indexed_max(field)
+      with_default_scope.indexed_max(field)
     end
   end
 
   module Criterion
     class Selector < Hash