Add struct attr_reader on DefaultResolver

Author: alextwoods

gems/aws-sdk-core/lib/aws-sdk-core/plugins/regional_endpoint.rb

@@ -152,16 +152,10 @@ def resolve_endpoint(cfg)
 
           # preserve legacy (pre EP2) client.config.endpoint still resolves a value
           # when needed.
-          struct = cfg.instance_variable_get(:@struct)
-          if struct
-            # need a separate proc to get namespace/private access to resolve_legacy_endpoint
-            b = proc { resolve_legacy_endpoint(struct) }
-            struct.define_singleton_method(:endpoint) { @endpoint ||= b.call }
-            nil
-          else
-            # backup in case internal details of config resolver change
-            resolve_legacy_endpoint(cfg)
-          end
+          # need a separate proc to get namespace/private access to resolve_legacy_endpoint
+          b = proc { resolve_legacy_endpoint(cfg.struct) }
+          cfg.struct.define_singleton_method(:endpoint) { @endpoint ||= b.call }
+          nil
         end
 
         # get a custom configured endpoint from ENV or configuration

gems/aws-sdk-core/lib/seahorse/client/configuration.rb

@@ -187,6 +187,8 @@ def initialize(struct)
           @members = Set.new(@struct.members)
         end
 
+        attr_reader :struct
+
         def resolve
           @members.each { |opt_name| value_at(opt_name) }
         end