hasMany collection columns (#2415)

Author: jubilee2

docs/customizing_dashboards.md

@@ -113,6 +113,9 @@ association `belongs_to :country`, from your model.
 
 **Field::HasMany**
 
+`:collection_attributes` - Set the columns to display in the show view. 
+Default is COLLECTION_ATTRIBUTES in dashboard.
+
 `:limit` - The number of resources (paginated) to display in the show view. To disable pagination,
 set this to `0` or `false`. Default is `5`.
 

lib/administrate/field/has_many.rb

@@ -22,7 +22,11 @@ def self.permitted_attribute(attr, _options = {})
       end
 
       def associated_collection(order = self.order)
-        Administrate::Page::Collection.new(associated_dashboard, order: order)
+        Administrate::Page::Collection.new(
+          associated_dashboard,
+          order: order,
+          collection_attributes: options[:collection_attributes],
+        )
       end
 
       def attribute_key

lib/administrate/page/collection.rb

@@ -4,6 +4,7 @@ module Administrate
   module Page
     class Collection < Page::Base
       def attribute_names
+        options.fetch(:collection_attributes, nil) ||
         dashboard.collection_attributes
       end
 

spec/example_app/app/dashboards/order_dashboard.rb

@@ -11,7 +11,9 @@ class OrderDashboard < Administrate::BaseDashboard
     address_state: Field::String,
     address_zip: Field::String,
     customer: Field::BelongsTo.with_options(order: "name"),
-    line_items: Field::HasMany,
+    line_items: Field::HasMany.with_options(
+      collection_attributes: %i[product quantity unit_price total_price],
+    ),
     total_price: Field::Number.with_options(prefix: "$", decimals: 2),
     shipped_at: Field::DateTime,
     payments: Field::HasMany,

spec/features/show_page_spec.rb

@@ -265,6 +265,21 @@
     end
   end
 
+  it "displays specified collection_attributes for the has_many association" do
+    line_item = create(:line_item)
+
+    visit admin_order_path(line_item.order)
+
+    within(table_for_attribute(:line_items)) do
+      columns = all("tr th").map do |e|
+        e[:class]&.split&.last&.split("--line_item_")&.last
+      end
+      expect(%w[product quantity unit_price total_price]).to(
+        eq(columns.first(4)),
+      )
+    end
+  end
+
   def ids_in_table
     all("tr td:first-child").map(&:text).map(&:to_i)
   end