[BuildTools] Support structure with no members key (aws#1971)

Author: cjyclaire

build_tools/aws-sdk-code-generator/lib/aws-sdk-code-generator/apply_docs.rb

@@ -29,7 +29,7 @@ def apply_docs(docs)
           case @api['shapes'][ref_shape]['type']
           when 'structure'
             shape = @api['shapes'][ref_shape]
-            if shape
+            if shape && shape['members']
               member = shape['members'][ref_member]
               member['documentation'] = ref_docs if member
             end

build_tools/aws-sdk-code-generator/lib/aws-sdk-code-generator/client_operation_documentation.rb

@@ -101,7 +101,7 @@ def option_tags(operation, api)
 
     def return_tag(operation, api)
       output = Api.shape(operation['output'], api)
-      if output && output['members'].size > 0
+      if output && output['members'] && output['members'].size > 0
         shape_name = operation.fetch('output').fetch('shape')
         type = "Types::#{shape_name}"
         _, shape = Api.resolve(shape_name, api)
@@ -198,7 +198,7 @@ def request_syntax_example(method_name, operation, api)
 
     def response_structure_example(operation, api)
       output = Api.shape(operation['output'], api) if operation['output']
-      if output && output['members'].size > 0
+      if output && output['members'] && output['members'].size > 0
         Docstring.block_comment(ClientResponseStructureExample.new(
           shape_ref: operation['output'],
           api: api

build_tools/aws-sdk-code-generator/lib/aws-sdk-code-generator/client_response_structure_example.rb

@@ -36,7 +36,7 @@ def structure(ref, context, visited)
         event_ctx.unshift("#{context} #=> Enumerator")
         event_ctx.unshift("All events are available at #{context}:")
         return event_ctx
-      else
+      elsif shape['members']
         shape['members'].each_pair do |member_name, member_ref|
           lines += entry(member_ref, "#{context}.#{underscore(member_name)}", visited)
         end

build_tools/customizations.rb

@@ -42,7 +42,7 @@ def exclude_eventstream(api)
 
       def is_eventstream?(api, shape_name)
         shape = api['shapes'][shape_name]
-        if shape['type'] == 'structure'
+        if shape['type'] == 'structure' && shape['members']
           eventstream = false
           shape['members'].each do |_, m_ref|
             eventstream ||= api['shapes'][m_ref['shape']]['eventstream']

tasks/update-sensitive-params.rake

@@ -3,7 +3,7 @@ task 'update-sensitive-params' do
   sensitive = []
   BuildTools::Services.each do |svc|
     svc.api['shapes'].each_pair do |shape_name, shape|
-      if shape['type'] == 'structure'
+      if shape['type'] == 'structure' && shape['members']
         shape['members'].each_pair do |member_name, member_ref|
           if 
             member_ref['sensitive'] ||