lib/dynamoid/criteria/chain.rb in dynamoid-3.2.0 vs lib/dynamoid/criteria/chain.rb in dynamoid-3.3.0

@@ -157,10 +157,15 @@
 
       def find_by_pages(&block)
         pages.each(&block)
       end
 
+      def project(*fields)
+        @project = fields.map(&:to_sym)
+        self
+      end
+
       private
 
       # The actual records referenced by the association.
       #
       # @return [Enumerator] an iterator of the found records.
@@ -188,26 +193,32 @@
       #
       # @return [Enumerator] an iterator of the found pages. An array of records
       #
       # @since 3.1.0
       def pages_via_query
-        Enumerator.new do |yielder|
+        Enumerator.new do |y|
           Dynamoid.adapter.query(source.table_name, range_query).each do |items, metadata|
-            yielder.yield items.map { |hash| source.from_database(hash) }, metadata.slice(:last_evaluated_key)
+            page = items.map { |h| source.from_database(h) }
+            options = metadata.slice(:last_evaluated_key)
+
+            y.yield page, options
           end
         end
       end
 
       # If the query does not match an index, we'll manually scan the associated table to find results.
       #
       # @return [Enumerator] an iterator of the found pages. An array of records
       #
       # @since 3.1.0
       def pages_via_scan
-        Enumerator.new do |yielder|
+        Enumerator.new do |y|
           Dynamoid.adapter.scan(source.table_name, scan_query, scan_opts).each do |items, metadata|
-            yielder.yield(items.map { |hash| source.from_database(hash) }, metadata.slice(:last_evaluated_key))
+            page = items.map { |h| source.from_database(h) }
+            options = metadata.slice(:last_evaluated_key)
+
+            y.yield page, options
           end
         end
       end
 
       def issue_scan_warning
@@ -269,10 +280,17 @@
                  { in: val }
                when 'contains'
                  { contains: val }
                when 'not_contains'
                  { not_contains: val }
+               # NULL/NOT_NULL operators don't have parameters
+               # So { null: true } means NULL check and { null: false } means NOT_NULL one
+               # The same logic is used for { not_null: BOOL }
+               when 'null'
+                 val ? { null: nil } : { not_null: nil }
+               when 'not_null'
+                 val ? { not_null: nil } : { null: nil }
                end
 
         { name.to_sym => hash }
       end
 
@@ -312,14 +330,19 @@
         end
 
         opts.merge(query_opts).merge(consistent_opts)
       end
 
+      # TODO casting should be operator aware
+      # e.g. for NULL operator value should be boolean
+      # and isn't related to an attribute own type
       def type_cast_condition_parameter(key, value)
         return value if %i[array set].include?(source.attributes[key.to_sym][:type])
 
-        if !value.respond_to?(:to_ary)
+        if [true, false].include?(value) # Support argument for null/not_null operators
+          value
+        elsif !value.respond_to?(:to_ary)
           options = source.attributes[key.to_sym]
           value_casted = TypeCasting.cast_field(value, options)
           Dumping.dump_field(value_casted, options)
         else
           value.to_ary.map do |el|
@@ -354,17 +377,20 @@
         key
       end
 
       def query_opts
         opts = {}
+        # Don't specify select = ALL_ATTRIBUTES option explicitly because it's
+        # already a default value of Select statement. Explicite Select value
+        # conflicts with AttributesToGet statement (project option).
         opts[:index_name] = @key_fields_detector.index_name if @key_fields_detector.index_name
-        opts[:select] = 'ALL_ATTRIBUTES'
         opts[:record_limit] = @record_limit if @record_limit
         opts[:scan_limit] = @scan_limit if @scan_limit
         opts[:batch_size] = @batch_size if @batch_size
         opts[:exclusive_start_key] = start_key if @start
         opts[:scan_index_forward] = @scan_index_forward
+        opts[:project] = @project
         opts
       end
 
       def scan_query
         {}.tap do |opts|
@@ -384,9 +410,10 @@
         opts[:record_limit] = @record_limit if @record_limit
         opts[:scan_limit] = @scan_limit if @scan_limit
         opts[:batch_size] = @batch_size if @batch_size
         opts[:exclusive_start_key] = start_key if @start
         opts[:consistent_read] = true if @consistent_read
+        opts[:project] = @project
         opts
       end
     end
   end
 end