Improvements to make V4 work

gems/smithy-cbor/lib/smithy-cbor/deserializer.rb

@@ -63,6 +63,7 @@ def map(shape, values, target = nil)
       end
 
       def structure(shape, values, target = nil)
+        # TODO: iterate shape members instead of values
         return Schema::EmptyStructure.new if shape == Prelude::Unit
 
         target = shape.type.new if target.nil?
@@ -77,6 +78,7 @@ def structure(shape, values, target = nil)
       end
 
       def union(shape, values, target = nil)
+        # TODO: delete target instead of checking key?
         key, value = values.flatten
         return nil if key.nil? || key == ' __target'
 

gems/smithy-client/lib/smithy-client.rb

@@ -24,6 +24,7 @@
 require_relative 'smithy-client/plugin'
 require_relative 'smithy-client/plugin_list'
 require_relative 'smithy-client/retry'
+require_relative 'smithy-client/util'
 require_relative 'smithy-client/input'
 require_relative 'smithy-client/output'
 require_relative 'smithy-client/base'

gems/smithy-client/lib/smithy-client/base.rb

@@ -156,10 +156,7 @@ def service
         end
 
         # @param [ServiceShape] service
-        def service=(service)
-          @service = service
-          define_operation_methods
-        end
+        attr_writer :service
 
         # @option options [ServiceShape] :service (ServiceShape.new)
         # @option options [Array<Plugin>] :plugins ([]) A list of plugins to
@@ -177,18 +174,6 @@ def define(options = {})
 
         private
 
-        def define_operation_methods
-          operations_module = Module.new
-          @service.operation_names.each do |method_name|
-            operations_module.send(:define_method, method_name) do |*args, &block|
-              params = args[0] || {}
-              options = args[1] || {}
-              build_input(method_name, params).send_request(options, &block)
-            end
-          end
-          include(operations_module)
-        end
-
         def build_plugins
           plugins.map { |plugin| plugin.is_a?(Class) ? plugin.new : plugin }
         end

gems/smithy-client/lib/smithy-client/errors.rb

@@ -29,7 +29,7 @@ def initialize(context, message, data)
           @code = self.class.code
           @context = context
           @message = extract_message(message, data)
-          @data = data
+          @data = data # TODO: delegate to this?
           super(@message)
         end
 

gems/smithy-client/lib/smithy-client/plugins/checksum_required.rb

@@ -0,0 +1,51 @@
+# frozen_string_literal: true
+
+require 'openssl'
+
+module Smithy
+  module Client
+    module Plugins
+      # @api private
+      class ChecksumRequired < Plugin
+        def add_handlers(handlers, _config)
+          # Ensure checksum is computed AFTER the request is built but BEFORE it is signed
+          handlers.add(Handler, priority: 15)
+        end
+
+        # @api private
+        class Handler < Client::Handler
+          CHUNK_SIZE = 1 * 1024 * 1024 # one MB
+
+          def call(context)
+            if checksum_required_operation?(context)
+              context.request.headers['Content-Md5'] ||= md5(context.request.body)
+            end
+            @handler.call(context)
+          end
+
+          private
+
+          def checksum_required_operation?(context)
+            context.operation.traits.include?('smithy.api#httpChecksumRequired')
+          end
+
+          def md5(value)
+            md5 = OpenSSL::Digest.new('MD5')
+            update_in_chunks(md5, value)
+            md5.base64digest
+          end
+
+          def update_in_chunks(digest, io)
+            loop do
+              chunk = io.read(CHUNK_SIZE)
+              break unless chunk
+
+              digest.update(chunk)
+            end
+            io.rewind
+          end
+        end
+      end
+    end
+  end
+end

gems/smithy-client/lib/smithy-client/plugins/host_prefix.rb

@@ -0,0 +1,69 @@
+# frozen_string_literal: true
+
+module Smithy
+  module Client
+    module Plugins
+      # @api private
+      class HostPrefix < Plugin
+        option(
+          :disable_host_prefix_injection,
+          default: false,
+          doc_type: 'Boolean',
+          docstring: 'When true, the SDK will not prepend the modeled host prefix to the endpoint.'
+        ) do |_config|
+          value = ENV['DISABLE_HOST_PREFIX_INJECTION'] || 'false'
+          Util.str_to_bool(value)
+        end
+
+        def after_initialize(client)
+          validate_disable_host_prefix_injection(client.config)
+        end
+
+        def validate_disable_host_prefix_injection(config)
+          return if [true, false].include?(config.disable_host_prefix_injection)
+
+          raise ArgumentError,
+                ':disable_host_prefix_injection must be either `true` or `false`'
+        end
+
+        def add_handlers(handlers, config)
+          handlers.add(Handler, priority: 25) unless config.disable_host_prefix_injection
+        end
+
+        # @api private
+        class Handler < Smithy::Client::Handler
+          def call(context)
+            host_prefix = context.operation.traits.dig('smithy.api#endpoint', 'hostPrefix')
+            apply_host_prefix(context, host_prefix) if host_prefix
+            @handler.call(context)
+          end
+
+          private
+
+          # TODO: optimize this to collect all labels in one pass
+          def apply_host_prefix(context, host_prefix)
+            input = context.operation.input
+            prefix = host_prefix.gsub(/\{.+?}/) do |label|
+              label_value(input, label.delete('{}'), context.params)
+            end
+            context.request.endpoint.host = prefix + context.request.endpoint.host
+          end
+
+          def label_value(input, label, params)
+            name = nil
+            input.members.each do |member_name, member_shape|
+              next unless member_shape.traits.include?('smithy.api#hostLabel')
+              next unless member_shape.name == label
+
+              name = member_name
+            end
+            raise ArgumentError, "#{label} is not a valid host label" if name.nil?
+            raise ArgumentError, "params[#{name}] must not be nil or blank" if params[name].nil? || params[name].empty?
+
+            params[name]
+          end
+        end
+      end
+    end
+  end
+end

gems/smithy-client/lib/smithy-client/plugins/idempotency_token.rb

@@ -0,0 +1,34 @@
+# frozen_string_literal: true
+
+require 'securerandom'
+
+module Smithy
+  module Client
+    module Plugins
+      # @api private
+      class IdempotencyToken < Plugin
+        def add_handlers(handlers, _config)
+          handlers.add(Handler, step: :initialize)
+        end
+
+        # @api private
+        class Handler < Client::Handler
+          def call(context)
+            apply_idempotency_token(context.operation.input, context.params)
+            @handler.call(context)
+          end
+
+          private
+
+          def apply_idempotency_token(input, params)
+            input.members.each do |member_name, member_shape|
+              next unless member_shape.traits.include?('smithy.api#idempotencyToken')
+
+              params[member_name] ||= SecureRandom.uuid
+            end
+          end
+        end
+      end
+    end
+  end
+end