Extract common method

lib/tasks/layers.rake

@@ -124,6 +124,14 @@ namespace :carto do
       puts "Finished. Total: #{total}. Errors: #{errors}"
     end
 
+    module LayersRake
+      def self.update_layer(layer, options, persisted)
+        layer.options = options
+        layer.user.viewer = false # To avoid validation issues
+        layer.save! if persisted
+      end
+    end
+
     desc "Syncs all layers with the configuration from app_config"
     task sync_basemaps_from_app_config: :environment do
       include Carto::MapcappedVisualizationUpdater
@@ -155,23 +163,23 @@ namespace :carto do
         next unless visualization.user
         begin
           success = update_visualization_and_mapcap(visualization) do |vis, persisted|
+            # Find visualization tiled base layers
             base_layers = vis.layers.select(&:tiled?)
             next true unless base_layers.count.between?(1, 2) # Other kind of basemaps (e.g: plain color), skip
             bottom_layer, labels_layer = base_layers.sort_by(&:order)
 
+            # Find basemap in configuration
             class_name = bottom_layer.options['className']
             attributes = basemaps_by_class_name[class_name]
             next true unless attributes # Unknown basemap class: do nothing (e.g: custom basemap)
 
-            bottom_layer.options = attributes.except('default')
-            bottom_layer.user.viewer = false # To avoid validation issues
-            bottom_layer.save! if persisted
+            # Update bottom layer
+            LayersRake.update_layer(bottom_layer, attributes.except('default'), persisted)
 
+            # Update top layer (if present)
             if labels_layer && attributes['labels']
               default_labels_layer = Carto::LayerFactory.build_default_labels_layer(bottom_layer)
-              labels_layer.options = default_labels_layer.options
-              labels_layer.user.viewer = false # To avoid validation issues
-              labels_layer.save! if persisted
+              LayersRake.update_layer(labels_layer, default_labels_layer.options, persisted)
             elsif labels_layer
               STDERR.puts "WARN: Visualization #{vis.id} has label but basemap class #{class_name} does not"
             elsif attributes['labels']