Extract fluent interfaces for SearchBuilder start/page/rows

lib/blacklight/search_builder.rb

@@ -80,34 +80,64 @@ def blacklight_config
       scope.blacklight_config
     end
 
-    protected
-    def request
-      Blacklight::Solr::Request.new
+    def start start = nil
+      if start
+        @start = start.to_i
+        self
+      else
+        @start ||= (page - 1) * (rows || 10)
+
+        val = @start || 0
+        val = 0 if @start < 0
+        val
+      end
     end
+    alias_method :padding, :start
 
-    def page
-      if blacklight_params[:page].blank?
-        1
+    def page page = nil
+      if page
+        @page = page.to_i
+        @page = 1 if @page < 1
+        self
       else
-        blacklight_params[:page].to_i
+        @page ||= begin
+          page = if blacklight_params[:page].blank?
+            1
+          else
+            blacklight_params[:page].to_i
+          end
+
+          page
+        end
       end
     end
 
-    def rows default = nil
-      # default number of rows
-      rows = default
-      rows ||= blacklight_config.default_per_page
-      rows ||= 10
+    def rows rows = nil
+      if rows
+        @rows = rows.to_i
+        @rows = blacklight_config.max_per_page if @rows > blacklight_config.max_per_page
+        self
+      else
+        @rows ||= begin
+          rows = blacklight_config.default_per_page
 
-      # user-provided parameters should override any default row
-      rows = blacklight_params[:rows].to_i unless blacklight_params[:rows].blank?
-      rows = blacklight_params[:per_page].to_i unless blacklight_params[:per_page].blank?
+          # user-provided parameters should override any default row
+          rows = blacklight_params[:rows].to_i unless blacklight_params[:rows].blank?
+          rows = blacklight_params[:per_page].to_i unless blacklight_params[:per_page].blank?
 
-      # ensure we don't excede the max page size
-      rows = blacklight_config.max_per_page if rows.to_i > blacklight_config.max_per_page
+          # ensure we don't excede the max page size
+          rows = blacklight_config.max_per_page if rows.to_i > blacklight_config.max_per_page
 
+          rows.to_i unless rows.nil?
+        end
+      end
+    end
 
-      rows
+    alias_method :per, :rows
+
+    protected
+    def request
+      Blacklight::Solr::Request.new
     end
 
     def sort

lib/blacklight/search_helper.rb

@@ -98,8 +98,11 @@ def get_search_results(user_params = params || {}, extra_controller_params = {})
   # @param [List<Symbol] processor_chain a list of filter methods to run
   # @return [Blacklight::SolrResponse] the solr response object
   def search_results(user_params, search_params_logic)
-    query = search_builder(search_params_logic).with(user_params).query
-    response = repository.search(query)
+    builder = search_builder(search_params_logic).with(user_params)
+    builder.page(user_params[:page]) if user_params[:page]
+    builder.rows(user_params[:per_page] || user_params[:rows]) if user_params[:per_page] or user_params[:rows]
+
+    response = repository.search(builder.query)
 
     case
     when (response.grouped? && grouped_key_for_results)
@@ -188,21 +191,18 @@ def get_facet_pagination(facet_field, user_params=params || {}, extra_controller
   # the Blacklight app-level request params that define the search.
   # @return [Blacklight::SolrDocument, nil] the found document or nil if not found
   def get_single_doc_via_search(index, request_params)
-    request_params = search_builder.with(request_params).processed_parameters
-
-    request_params[:start] = (index - 1) # start at 0 to get 1st doc, 1 to get 2nd.
-    request_params[:rows] = 1
-    request_params[:fl] = '*'
-    response = repository.search(request_params)
+    query = search_builder.with(request_params).start(index - 1).rows(1).query(fl: "*")
+    response = repository.search(query)
     response.documents.first
   end
   deprecation_deprecate :get_single_doc_via_search
 
   # Get the previous and next document from a search result
   # @return [Blacklight::SolrResponse, Array<Blacklight::SolrDocument>] the solr response and a list of the first and last document
   def get_previous_and_next_documents_for_search(index, request_params, extra_controller_params={})
+    p = previous_and_next_document_params(index)
 
-    query = search_builder.with(request_params).query(extra_controller_params.merge(previous_and_next_document_params(index)))
+    query = search_builder.with(request_params).start(p.delete(:start)).rows(p.delete(:rows)).query(extra_controller_params.merge(p))
     response = repository.search(query)
 
     document_list = response.documents

lib/blacklight/solr/search_builder.rb

@@ -167,10 +167,12 @@ def add_solr_fields_to_query solr_parameters
     # copy paging params from BL app over to solr, changing
     # app level per_page and page to Solr rows and start. 
     def add_paging_to_solr(solr_params)
-      # user-provided parameters should override any default row
-      solr_params[:rows] = rows(solr_params[:rows])
-      if page > 1
-        solr_params[:start] = solr_params[:rows].to_i * (page - 1)
+      rows(solr_params[:rows] || 10) if rows.nil?
+
+      solr_params[:rows] = rows
+
+      if start != 0
+        solr_params[:start] = start
       end
     end
 

spec/lib/blacklight/search_builder_spec.rb

@@ -100,31 +100,33 @@
   end
 
   describe "#rows" do
-    it "should be the per_page parameter" do
-      expect(subject.with(per_page: 5).send(:rows)).to eq 5
+
+    it "should be nil if no value is set" do
+      blacklight_config.default_per_page = nil
+      blacklight_config.per_page = []
+      expect(subject.rows).to be_nil
     end
 
-    it "should support the legacy 'rows' parameter" do
-      expect(subject.with(rows: 10).send(:rows)).to eq 10
+    it "should set the number of rows" do
+      expect(subject.rows(17).rows).to eq 17
     end
 
-    it "should use the provided default" do
-      expect(subject.send(:rows, 17)).to eq 17
+    it "should be the per_page parameter" do
+      expect(subject.with(per_page: 5).rows).to eq 5
     end
 
-    it "should be set to the configured default" do
-      blacklight_config.default_per_page = 42
-      expect(subject.send(:rows)).to eq 42
+    it "should support the legacy 'rows' parameter" do
+      expect(subject.with(rows: 10).rows).to eq 10
     end
 
-    it "should default to 10" do
-      blacklight_config.default_per_page = nil
-      expect(subject.send(:rows)).to eq 10
+    it "should be set to the configured default" do
+      blacklight_config.default_per_page = 42
+      expect(subject.rows).to eq 42
     end
 
     it "should limit the number of rows to the configured maximum" do
       blacklight_config.max_per_page = 1000
-      expect(subject.send(:rows, 1001)).to eq 1000
+      expect(subject.rows(1001).rows).to eq 1000
     end
   end
 

spec/lib/blacklight/solr/search_builder_spec.rb

@@ -40,7 +40,6 @@
                              :qf => "fieldOne^2.3 fieldTwo fieldThree^0.4",
                              :pf => "",
                              :spellcheck => 'false',
-                             :rows => "55",
                              :sort => "request_params_sort" }
                           )
       end
@@ -62,10 +61,6 @@
         expect(subject[:qt]).to eq blacklight_config[:default_solr_params][:qt]
       end
 
-      it "should take rows from search field definition where specified" do
-        expect(subject[:rows]).to eq "55"
-      end
-
       it "should take q from request params" do
         expect(subject[:q]).to eq "test query"
       end