feat: implemented basic cache of 30 sec in can-i-merge badges

lib/pact_broker/api/resources/badge_methods.rb

@@ -32,7 +32,7 @@ def policy_name
         end
 
         def moved_temporarily?
-          response.headers["Cache-Control"] = "no-cache"
+          set_cache_control("no-cache")
           begin
             badge_url
           rescue StandardError => e
@@ -46,6 +46,10 @@ def badge_url
           raise NotImplementedError
         end
 
+        def set_cache_control(cache_control_str)
+          response.headers["Cache-Control"] = cache_control_str
+        end
+
         private
 
         def label

lib/pact_broker/api/resources/can_i_merge_badge.rb

@@ -15,6 +15,7 @@ def badge_url
             # when there is no main branch version, we return an error badge url
             badge_service.error_badge_url("main branch version", "not found")
           else
+            set_cache_control("max-age=30") # override the cache control header to a default 30 seconds
             # we call badge_service to build the badge url
             badge_service.can_i_merge_badge_url(deployable: results)
           end

spec/lib/pact_broker/api/resources/can_i_merge_badge_spec.rb

@@ -35,6 +35,7 @@ module Resources
           it "return the badge URL" do
             expect(badge_service). to receive(:can_i_merge_badge_url).with(deployable: true)
             expect(subject.headers["Location"]).to eq "http://badge_url"
+            expect(subject.headers["Cache-Control"]).to eq "max-age=30"
           end
         end
 
@@ -44,6 +45,7 @@ module Resources
           it "returns an error badge URL" do
             expect(badge_service).to receive(:error_badge_url).with("pacticipant", "not found")
             expect(subject.headers["Location"]).to eq "http://error_badge_url"
+            expect(subject.headers["Cache-Control"]).to eq "no-cache"  
           end
         end