[15-minute fix] Add created_at to listings API response (#14437)

* Add created_at to listings API response

* Add created_at listing attribute to org controller

app/controllers/api/v0/listings_controller.rb

@@ -18,7 +18,7 @@ module Api
       # actual column name for the listing category, prefixed with classified_.
       ATTRIBUTES_FOR_SERIALIZATION = %i[
         id user_id organization_id title slug body_markdown cached_tag_list
-        classified_listing_category_id processed_html published
+        classified_listing_category_id processed_html published created_at
       ].freeze
       private_constant :ATTRIBUTES_FOR_SERIALIZATION
 

app/controllers/api/v0/organizations_controller.rb

@@ -17,7 +17,7 @@ module Api
 
       LISTINGS_FOR_SERIALIZATION = %i[
         id user_id organization_id title slug body_markdown cached_tag_list
-        classified_listing_category_id processed_html published
+        classified_listing_category_id processed_html published created_at
       ].freeze
       private_constant :LISTINGS_FOR_SERIALIZATION
 

app/views/api/v0/shared/_listing.json.jbuilder

@@ -14,3 +14,4 @@ json.extract!(
 json.listing_category_id listing.classified_listing_category_id
 json.tag_list            listing.cached_tag_list
 json.tags                listing.tag_list
+json.created_at          utc_iso_timestamp(listing.created_at)

spec/requests/api/v0/listings_spec.rb

@@ -106,6 +106,13 @@ RSpec.describe "Api::V0::Listings", type: :request do
       get api_listings_path
       expect(response.parsed_body.detect { |l| l["published"] == false }).to be_nil
     end
+
+    # Regression test for https://github.com/forem/forem/issues/14436
+    it "includes the created at timestamp for listings" do
+      get api_listings_path
+      listing = response.parsed_body.first
+      expect(listing["created_at"]).to match(/\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}Z/)
+    end
   end
 
   describe "GET /api/listings/category/:category" do