add a proc mechanism to Blacklight::Configuration#property to allow d…

…eferred resolution of some default values
projectblacklight · Oct 6, 2022 · d2fb198 · d2fb198
1 parent 388dd82
commit d2fb198
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Showing 2 changed files with 22 additions and 10 deletions.
diff --git a/lib/blacklight/configuration.rb b/lib/blacklight/configuration.rb
@@ -22,15 +22,13 @@ class Configuration < OpenStructWithHashAccess
       autoload :ShowField
     end
 
+    class_attribute :default_values, default: {}
+
     # Set up Blacklight::Configuration.default_values to contain the basic, required Blacklight fields
     class << self
       def property(key, default: nil)
         default_values[key] = default
       end
-
-      def default_values
-        @default_values ||= {}
-      end
     end
     # === Search request configuration
 
@@ -77,28 +75,28 @@ def default_values
     property :repository_class, default: Blacklight::Solr::Repository
     # @!attribute search_builder_class
     # @return [Class] class for converting Blacklight parameters to request parameters for the repository_class
-    property :search_builder_class, default: ::SearchBuilder
+    property :search_builder_class, default: -> { ::SearchBuilder }
     # @!attribute response_model
     # model that maps index responses to the blacklight response model
     # @return [Class]
     property :response_model, default: Blacklight::Solr::Response
     # @!attribute document_model
     # the model to use for each response document
     # @return [Class]
-    property :document_model, default: ::SolrDocument
+    property :document_model, default: -> { ::SolrDocument }
     # @!attribute document_factory
     # the factory that builds document
     # @return [Class]
-    property :document_factory, default: Blacklight::DocumentFactory
+    property :document_factory, default: -> { Blacklight::DocumentFactory }
     # @!attribute facet_paginator_class
     # Class for paginating long lists of facet fields
     # @return [Class]
-    property :facet_paginator_class, default: Blacklight::Solr::FacetPaginator
+    property :facet_paginator_class, default: -> { Blacklight::Solr::FacetPaginator }
     # @!attribute connection_config
     # repository connection configuration
     # @since v5.13.0
     # @return [Class]
-    property :connection_config, default: Blacklight.connection_config
+    property :connection_config, default: -> { Blacklight.connection_config }
 
     ##
     # == Blacklight view configuration
@@ -315,7 +313,7 @@ def default_values
     define_field_access :email_field, Blacklight::Configuration::DisplayField
 
     def initialize(hash = {})
-      super(self.class.default_values.deep_transform_values(&method(:_deep_copy)).merge(hash))
+      super(self.class.default_values.transform_values(&method(:process_dynamic_config)).deep_transform_values(&method(:_deep_copy)).merge(hash))
       yield(self) if block_given?
 
       @view_config ||= {}
@@ -562,6 +560,16 @@ def _deep_copy(value)
       end
     end
 
+    # Resolve default values that need to be evaluated at run-time
+    def process_dynamic_config(value)
+      case value
+      when Proc
+        value.call
+      else
+        value
+      end
+    end
+
     def action_config(action, default: :index)
       action_config = action_mapping[action]
       action_config ||= action_mapping[:default]

diff --git a/spec/models/blacklight/configuration_spec.rb b/spec/models/blacklight/configuration_spec.rb
@@ -26,6 +26,10 @@
 
       expect(config.a).to eq 3
     end
+
+    it "resolves default properties given as procs" do
+      expect(config.document_model).to eq(SolrDocument)
+    end
   end
 
   describe "defaults" do