Blacklight.default_index should respect the Blacklight adapter config…

…uration

lib/blacklight.rb

@@ -59,8 +59,31 @@ def self.add_routes(router, options = {})
     Blacklight::Routes.new(router, options).draw
   end
 
+  ##
+  # The default index connection for the search index
   def self.default_index
-    @default_index ||=  Blacklight::SolrRepository.new(Blacklight::Configuration.new)
+    @default_index ||= repository_class.new(default_configuration)
+  end
+
+  ##
+  # The configured repository class. By convention, this is
+  # the class Blacklight::{name of the adapter}::Repository, e.g.
+  #   elastic_search => Blacklight::ElasticSearch::Repository
+  def self.repository_class
+    case connection_config[:adapter]
+    when 'solr'
+      Blacklight::SolrRepository
+    when /::/
+      connection_config[:adapter].constantize
+    else
+      Blacklight.const_get("#{connection_config[:adapter]}/Repository".classify)
+    end
+  end
+
+  ##
+  # The default Blacklight configuration.
+  def self.default_configuration
+    Blacklight::Configuration.new
   end
 
   def self.connection_config

spec/lib/blacklight_spec.rb

@@ -11,5 +11,57 @@
     end
 
   end
+
+  describe '.default_index' do
+    context 'for a solr index' do
+      before do
+        allow(Blacklight).to receive(:connection_config).and_return(adapter: 'solr')
+      end
+
+      it 'is an instance of Blacklight::SolrRepository' do
+        expect(Blacklight.default_index).to be_a Blacklight::SolrRepository
+      end
+    end
+  end
+
+  describe '.repository_class' do
+    context 'for a solr index' do
+      before do
+        allow(Blacklight).to receive(:connection_config).and_return(adapter: 'solr')
+      end
+
+      it 'resolves to the SolrRepository implementation' do
+        expect(Blacklight.repository_class).to eq Blacklight::SolrRepository
+      end
+    end
+
+    context 'for an elastic_search index' do
+      before do
+        stub_const("Blacklight::ElasticSearch::Repository", double)
+        allow(Blacklight).to receive(:connection_config).and_return(adapter: 'elastic_search')
+      end
+
+      it 'resolves to the SolrRepository implementation' do
+        expect(Blacklight.repository_class).to eq Blacklight::ElasticSearch::Repository
+      end
+    end
+
+    context 'for an explicitly provided class' do
+      before do
+        stub_const("CustomSearch::Repository", double)
+        allow(Blacklight).to receive(:connection_config).and_return(adapter: 'CustomSearch::Repository')
+      end
+
+      it 'resolves to the custom implementation' do
+        expect(Blacklight.repository_class).to eq CustomSearch::Repository
+      end
+    end
+  end
+
+  describe '.default_configuration' do
+    it 'is a Blacklight configuration' do
+      expect(Blacklight.default_configuration).to be_a Blacklight::Configuration
+    end
+  end
 
 end