// newClient creates, initializes and returns a new service client instance.
func newClient(cfg aws.Config, handlers request.Handlers, endpoint, signingRegion string) *Lambda {
	svc := &Lambda{
		Client: client.New(
			cfg,
			metadata.ClientInfo{
				ServiceName:   ServiceName,
				SigningRegion: signingRegion,
				Endpoint:      endpoint,
				APIVersion:    "2015-03-31",
			},
			handlers,
		),
	}

	// Handlers
	svc.Handlers.Sign.PushBack(v4.Sign)
	svc.Handlers.Build.PushBack(restjson.Build)
	svc.Handlers.Unmarshal.PushBack(restjson.Unmarshal)
	svc.Handlers.UnmarshalMeta.PushBack(restjson.UnmarshalMeta)
	svc.Handlers.UnmarshalError.PushBack(restjson.UnmarshalError)

	// Run custom client initialization if present
	if initClient != nil {
		initClient(svc.Client)
	}

	return svc
}

// newClient creates, initializes and returns a new service client instance.
func newInputService6ProtocolTestClient(cfg aws.Config, handlers request.Handlers, endpoint, signingRegion string) *InputService6ProtocolTest {
	svc := &InputService6ProtocolTest{
		Client: client.New(
			cfg,
			metadata.ClientInfo{
				ServiceName:   "inputservice6protocoltest",
				SigningRegion: signingRegion,
				Endpoint:      endpoint,
				APIVersion:    "",
				JSONVersion:   "1.1",
				TargetPrefix:  "com.amazonaws.foo",
			},
			handlers,
		),
	}

	// Handlers
	svc.Handlers.Sign.PushBack(v4.Sign)
	svc.Handlers.Build.PushBack(jsonrpc.Build)
	svc.Handlers.Unmarshal.PushBack(jsonrpc.Unmarshal)
	svc.Handlers.UnmarshalMeta.PushBack(jsonrpc.UnmarshalMeta)
	svc.Handlers.UnmarshalError.PushBack(jsonrpc.UnmarshalError)

	return svc
}

// newClient creates, initializes and returns a new service client instance.
func newOutputService11ProtocolTestClient(cfg aws.Config, handlers request.Handlers, endpoint, signingRegion string) *OutputService11ProtocolTest {
	svc := &OutputService11ProtocolTest{
		Client: client.New(
			cfg,
			metadata.ClientInfo{
				ServiceName:   "outputservice11protocoltest",
				SigningRegion: signingRegion,
				Endpoint:      endpoint,
				APIVersion:    "",
			},
			handlers,
		),
	}

	// Handlers
	svc.Handlers.Sign.PushBack(v4.Sign)
	svc.Handlers.Build.PushBack(restjson.Build)
	svc.Handlers.Unmarshal.PushBack(restjson.Unmarshal)
	svc.Handlers.UnmarshalMeta.PushBack(restjson.UnmarshalMeta)
	svc.Handlers.UnmarshalError.PushBack(restjson.UnmarshalError)

	return svc
}

// NewClient returns a new EC2Metadata client. Should be used to create
// a client when not using a session. Generally using just New with a session
// is preferred.
//
// If an unmodified HTTP client is provided from the stdlib default, or no client
// the EC2RoleProvider's EC2Metadata HTTP client's timeout will be shortened.
// To disable this set Config.EC2MetadataDisableTimeoutOverride to false. Enabled by default.
func NewClient(cfg aws.Config, handlers request.Handlers, endpoint, signingRegion string, opts ...func(*client.Client)) *EC2Metadata {
	if !aws.BoolValue(cfg.EC2MetadataDisableTimeoutOverride) && httpClientZero(cfg.HTTPClient) {
		// If the http client is unmodified and this feature is not disabled
		// set custom timeouts for EC2Metadata requests.
		cfg.HTTPClient = &http.Client{
			// use a shorter timeout than default because the metadata
			// service is local if it is running, and to fail faster
			// if not running on an ec2 instance.
			Timeout: 5 * time.Second,
		}
	}

	svc := &EC2Metadata{
		Client: client.New(
			cfg,
			metadata.ClientInfo{
				ServiceName: ServiceName,
				Endpoint:    endpoint,
				APIVersion:  "latest",
			},
			handlers,
		),
	}

	svc.Handlers.Unmarshal.PushBack(unmarshalHandler)
	svc.Handlers.UnmarshalError.PushBack(unmarshalError)
	svc.Handlers.Validate.Clear()
	svc.Handlers.Validate.PushBack(validateEndpointHandler)

	// Add additional options to the service config
	for _, option := range opts {
		option(svc.Client)
	}

	return svc
}