Adds ability to exclude count from results

lib/brainstem/presenter.rb

@@ -28,6 +28,32 @@ def self.default_sort_order(sort_string = nil)
       end
     end
 
+    # @overload exclude_count
+    #   set exclude_count = true and allow_count = false (i.e. exclude the count and do not
+    #   do not allow a request for the count via the url query string)
+    #   @return [Boolean, Boolean]
+    # @overload exclude_count( allow: true )
+    #   set exclude_count = true and allow_count = false (i.e. exclude the count by default
+    #   but allows a request for it via the url query string with (e.g. ?count=true)
+    #   @return [Boolean, Boolean]    
+    # @overload exclude_count( exclude: false )
+    #   set exclude_count = false. This is only needed for testing to toggle back to the
+    #   including the count by default, otherwise some of the subsequent tests may fail
+    #   @return [Boolean, Boolean]
+    def self.exclude_count(exclude: true, allow: false)
+      [@exclude_count = exclude, @allow_count = allow]
+    end
+
+    def self.exclude_count?
+      @exclude_count == true ? true : false
+    end
+
+    def self.allow_count?
+      (@exclude_count == true && @allow_count == true) ? true : false
+    end
+
+
+
     # @overload sort_order(name, order)
     #   @param [Symbol] name The name of the sort order.
     #   @param [String] order The SQL string to use to sort the presented data.
@@ -191,6 +217,19 @@ def default_sort_order
       self.class.default_sort_order
     end
 
+    # @!attribute [r] exclude_count
+    # The boolean value set in the definition of this presenter to indicate if the count is excluded
+    def exclude_count?
+      self.class.exclude_count?
+    end
+
+    # @!attribute [r] allow_count
+    # The boolean value set in the definition of this presenter to indicate if the count may
+    # be included even if it has been excluded by default
+    def allow_count?
+      self.class.allow_count?
+    end
+
     # @!attribute [r] sort_orders
     # The sort orders that were declared in the definition of this presenter.
     def sort_orders

lib/brainstem/presenter_collection.rb

@@ -93,7 +93,13 @@ def presenting(name, options = {}, &block)
 
       models = perform_preloading records, includes_hash
       primary_models, associated_models = gather_associations(models, includes_hash)
-      struct = { :count => count, options[:as] => [], :results => [] }
+
+
+      if present_count?(options)
+        struct = { :count => count, options[:as] => [], :results => [] }
+      else
+        struct = { options[:as] => [], :results => [] }
+      end
 
       associated_models.each do |json_name, models|
         models.flatten!
@@ -154,7 +160,16 @@ def paginate(scope, options)
         offset = limit * (calculate_page(options) - 1)
       end
 
-      [scope.limit(limit).offset(offset).uniq, scope.select("distinct #{scope.connection.quote_table_name options[:table_name]}.id").count] # as of Rails 3.2.5, uniq.count generates the wrong SQL.
+      paginate_results = []
+      paginate_results << scope.limit(limit).offset(offset).uniq
+      if present_count?(options)
+        paginate_results << scope.select("distinct #{scope.connection.quote_table_name options[:table_name]}.id").count
+      else
+        paginate_results << :no_count_retrieved
+      end
+
+      paginate_results
+
     end
 
     def calculate_per_page(options)
@@ -387,6 +402,16 @@ def set_default_filters_option!(options)
       options[:apply_default_filters] = [true, "true", "TRUE", 1, "1"].include? options[:params].delete(:apply_default_filters)
     end
 
+
+    # Return boolean indicating whether or not the count should be presented
+    def present_count?(options)
+      p = options[:presenter]
+      count_true = [true, "true", "TRUE", 1, "1"].include? options[:params][:count]
+      count_false = [false, "false", "FALSE", 0, "0"].include? options[:params][:count]
+      ( !p.exclude_count? && !count_false ) || ( p.allow_count? && count_true )
+    end
+
+
     # Class Methods
 
     # In Rails 4.2, ActiveRecord::Base#reflections started being keyed by strings instead of symbols.

spec/brainstem/presenter_collection_spec.rb

@@ -149,6 +149,33 @@ class MyException < Exception; end
           result = @presenter_collection.presenting("workspaces", :params => { :per_page => 2, :page => 1 }) { Workspace.order('id desc') }
           expect(result[:count]).to eq(Workspace.count)
         end
+
+        it "are excluded when exclude_count method defined" do
+          WorkspacePresenter.exclude_count
+          result = @presenter_collection.presenting("workspaces", :params => { :per_page => 2, :page => 1 }) { Workspace.unscoped }
+          WorkspacePresenter.exclude_count(exclude: false)
+          expect(result[:count]).to be_nil
+        end
+
+        it "are included when exclude_count method defined with 'allow = true' and 'count=true' passed in url query string" do
+          WorkspacePresenter.exclude_count(allow: true)
+          result = @presenter_collection.presenting("workspaces", :params => { :per_page => 2, :page => 1, :count => "true" }) { Workspace.unscoped }
+          WorkspacePresenter.exclude_count(exclude: false)
+          expect(result[:count]).to eq(Workspace.count)
+        end
+
+        it "are excluded when exclude_count method defined without 'allow = true' and 'count=true' passed in url query string" do
+          WorkspacePresenter.exclude_count
+          result = @presenter_collection.presenting("workspaces", :params => { :per_page => 2, :page => 1, :count => "true" }) { Workspace.unscoped }
+          WorkspacePresenter.exclude_count(exclude: false)
+          expect(result[:count]).to be_nil
+        end
+
+        it "are excluded when count=false appears in the url query string" do
+          result = @presenter_collection.presenting("workspaces", :params => { :per_page => 2, :page => 1, :count => "false" }) { Workspace.unscoped }
+          expect(result[:count]).to be_nil
+        end
+
       end
     end