-import Ajv, { type JSONSchemaType } from 'ajv';
-import ajvFormats from 'ajv-formats';
+import _Ajv, { type ValidateFunction } from 'ajv'
+import _ajvFormats from 'ajv-formats'
-import OCPPError from '../../exception/OCPPError';
-import PerformanceStatistics from '../../performance/PerformanceStatistics';
-import type { EmptyObject } from '../../types/EmptyObject';
-import type { HandleErrorParams } from '../../types/Error';
-import type { JsonObject, JsonType } from '../../types/JsonType';
-import { ErrorType } from '../../types/ocpp/ErrorType';
-import { MessageType } from '../../types/ocpp/MessageType';
-import type { OCPPVersion } from '../../types/ocpp/OCPPVersion';
+import { OCPPConstants } from './OCPPConstants.js'
+import type { OCPPResponseService } from './OCPPResponseService.js'
+import { OCPPServiceUtils } from './OCPPServiceUtils.js'
+import type { ChargingStation } from '../../charging-station/index.js'
+import { OCPPError } from '../../exception/index.js'
+import { PerformanceStatistics } from '../../performance/index.js'
import {
+ ChargingStationEvents,
type ErrorCallback,
+ type ErrorResponse,
+ ErrorType,
type IncomingRequestCommand,
+ type JsonType,
+ MessageType,
+ type OCPPVersion,
type OutgoingRequest,
RequestCommand,
type RequestParams,
+ type Response,
type ResponseCallback,
- type ResponseType,
-} from '../../types/ocpp/Requests';
-import type { ErrorResponse, Response } from '../../types/ocpp/Responses';
-import Constants from '../../utils/Constants';
-import logger from '../../utils/Logger';
-import Utils from '../../utils/Utils';
-import type ChargingStation from '../ChargingStation';
-import type OCPPResponseService from './OCPPResponseService';
-import { OCPPServiceUtils } from './OCPPServiceUtils';
+ type ResponseType
+} from '../../types/index.js'
+import {
+ clone,
+ formatDurationMilliSeconds,
+ handleSendMessageError,
+ logger
+} from '../../utils/index.js'
+type Ajv = _Ajv.default
+// eslint-disable-next-line @typescript-eslint/no-redeclare
+const Ajv = _Ajv.default
+const ajvFormats = _ajvFormats.default
+
+const moduleName = 'OCPPRequestService'
-const moduleName = 'OCPPRequestService';
+const defaultRequestParams: RequestParams = {
+ skipBufferingOnError: false,
+ triggerMessage: false,
+ throwError: false
+}
-export default abstract class OCPPRequestService {
- private static instance: OCPPRequestService | null = null;
- private readonly version: OCPPVersion;
- private readonly ajv: Ajv;
- private readonly ocppResponseService: OCPPResponseService;
- protected abstract jsonSchemas: Map<RequestCommand, JSONSchemaType<JsonObject>>;
+export abstract class OCPPRequestService {
+ private static instance: OCPPRequestService | null = null
+ private readonly version: OCPPVersion
+ private readonly ocppResponseService: OCPPResponseService
+ protected readonly ajv: Ajv
+ protected abstract payloadValidateFunctions: Map<RequestCommand, ValidateFunction<JsonType>>
- protected constructor(version: OCPPVersion, ocppResponseService: OCPPResponseService) {
- this.version = version;
+ protected constructor (version: OCPPVersion, ocppResponseService: OCPPResponseService) {
+ this.version = version
this.ajv = new Ajv({
keywords: ['javaType'],
- multipleOfPrecision: 2,
- });
- ajvFormats(this.ajv);
- this.ocppResponseService = ocppResponseService;
- this.requestHandler.bind(this);
- this.sendMessage.bind(this);
- this.sendResponse.bind(this);
- this.sendError.bind(this);
- this.internalSendMessage.bind(this);
- this.buildMessageToSend.bind(this);
- this.validateRequestPayload.bind(this);
- this.validateIncomingRequestResponsePayload.bind(this);
+ multipleOfPrecision: 2
+ })
+ ajvFormats(this.ajv)
+ this.ocppResponseService = ocppResponseService
+ this.requestHandler = this.requestHandler.bind(this)
+ this.sendMessage = this.sendMessage.bind(this)
+ this.sendResponse = this.sendResponse.bind(this)
+ this.sendError = this.sendError.bind(this)
+ this.internalSendMessage = this.internalSendMessage.bind(this)
+ this.buildMessageToSend = this.buildMessageToSend.bind(this)
+ this.validateRequestPayload = this.validateRequestPayload.bind(this)
+ this.validateIncomingRequestResponsePayload =
+ this.validateIncomingRequestResponsePayload.bind(this)
}
public static getInstance<T extends OCPPRequestService>(
ocppResponseService: OCPPResponseService
): T {
if (OCPPRequestService.instance === null) {
- OCPPRequestService.instance = new this(ocppResponseService);
+ OCPPRequestService.instance = new this(ocppResponseService)
}
- return OCPPRequestService.instance as T;
+ return OCPPRequestService.instance as T
}
- public async sendResponse(
+ public async sendResponse (
chargingStation: ChargingStation,
messageId: string,
messagePayload: JsonType,
messagePayload,
MessageType.CALL_RESULT_MESSAGE,
commandName
- );
+ )
} catch (error) {
- this.handleSendMessageError(chargingStation, commandName, error as Error, {
- throwError: true,
- });
+ handleSendMessageError(chargingStation, commandName, error as Error, {
+ throwError: true
+ })
+ return null
}
}
- public async sendError(
+ public async sendError (
chargingStation: ChargingStation,
messageId: string,
ocppError: OCPPError,
ocppError,
MessageType.CALL_ERROR_MESSAGE,
commandName
- );
+ )
} catch (error) {
- this.handleSendMessageError(chargingStation, commandName, error as Error);
+ handleSendMessageError(chargingStation, commandName, error as Error)
+ return null
}
}
- protected async sendMessage(
+ protected async sendMessage (
chargingStation: ChargingStation,
messageId: string,
messagePayload: JsonType,
commandName: RequestCommand,
- params: RequestParams = {
- skipBufferingOnError: false,
- triggerMessage: false,
- }
+ params?: RequestParams
): Promise<ResponseType> {
+ params = {
+ ...defaultRequestParams,
+ ...params
+ }
try {
return await this.internalSendMessage(
chargingStation,
MessageType.CALL_MESSAGE,
commandName,
params
- );
+ )
} catch (error) {
- this.handleSendMessageError(chargingStation, commandName, error as Error);
+ handleSendMessageError(chargingStation, commandName, error as Error, {
+ throwError: params.throwError
+ })
+ return null
}
}
- private validateRequestPayload<T extends JsonObject>(
+ private validateRequestPayload<T extends JsonType>(
chargingStation: ChargingStation,
commandName: RequestCommand | IncomingRequestCommand,
payload: T
): boolean {
- if (chargingStation.getPayloadSchemaValidation() === false) {
- return true;
+ if (chargingStation.stationInfo?.ocppStrictCompliance === false) {
+ return true
}
- if (this.jsonSchemas.has(commandName as RequestCommand) === false) {
+ if (!this.payloadValidateFunctions.has(commandName as RequestCommand)) {
logger.warn(
`${chargingStation.logPrefix()} ${moduleName}.validateRequestPayload: No JSON schema found for command '${commandName}' PDU validation`
- );
- return true;
+ )
+ return true
}
- const validate = this.ajv.compile(this.jsonSchemas.get(commandName as RequestCommand));
- payload = Utils.cloneObject<T>(payload);
- OCPPServiceUtils.convertDateToISOString<T>(payload);
- if (validate(payload)) {
- return true;
+ const validate = this.payloadValidateFunctions.get(commandName as RequestCommand)
+ payload = clone<T>(payload)
+ OCPPServiceUtils.convertDateToISOString<T>(payload)
+ if (validate?.(payload) === true) {
+ return true
}
logger.error(
`${chargingStation.logPrefix()} ${moduleName}.validateRequestPayload: Command '${commandName}' request PDU is invalid: %j`,
- validate.errors
- );
+ validate?.errors
+ )
// OCPPError usage here is debatable: it's an error in the OCPP stack but not targeted to sendError().
throw new OCPPError(
- OCPPServiceUtils.ajvErrorsToErrorType(validate.errors),
+ OCPPServiceUtils.ajvErrorsToErrorType(validate?.errors),
'Request PDU is invalid',
commandName,
- JSON.stringify(validate.errors, null, 2)
- );
+ JSON.stringify(validate?.errors, undefined, 2)
+ )
}
- private validateIncomingRequestResponsePayload<T extends JsonObject>(
+ private validateIncomingRequestResponsePayload<T extends JsonType>(
chargingStation: ChargingStation,
commandName: RequestCommand | IncomingRequestCommand,
payload: T
): boolean {
- if (chargingStation.getPayloadSchemaValidation() === false) {
- return true;
+ if (chargingStation.stationInfo?.ocppStrictCompliance === false) {
+ return true
}
if (
- this.ocppResponseService.jsonIncomingRequestResponseSchemas.has(
+ !this.ocppResponseService.incomingRequestResponsePayloadValidateFunctions.has(
commandName as IncomingRequestCommand
- ) === false
+ )
) {
logger.warn(
- `${chargingStation.logPrefix()} ${moduleName}.validateIncomingRequestResponsePayload: No JSON schema found for command '${commandName}' PDU validation`
- );
- return true;
- }
- const validate = this.ajv.compile(
- this.ocppResponseService.jsonIncomingRequestResponseSchemas.get(
- commandName as IncomingRequestCommand
+ `${chargingStation.logPrefix()} ${moduleName}.validateIncomingRequestResponsePayload: No JSON schema validation function found for command '${commandName}' PDU validation`
)
- );
- payload = Utils.cloneObject<T>(payload);
- OCPPServiceUtils.convertDateToISOString<T>(payload);
- if (validate(payload)) {
- return true;
+ return true
+ }
+ const validate = this.ocppResponseService.incomingRequestResponsePayloadValidateFunctions.get(
+ commandName as IncomingRequestCommand
+ )
+ payload = clone<T>(payload)
+ OCPPServiceUtils.convertDateToISOString<T>(payload)
+ if (validate?.(payload) === true) {
+ return true
}
logger.error(
- `${chargingStation.logPrefix()} ${moduleName}.validateIncomingRequestResponsePayload: Command '${commandName}' reponse PDU is invalid: %j`,
- validate.errors
- );
+ `${chargingStation.logPrefix()} ${moduleName}.validateIncomingRequestResponsePayload: Command '${commandName}' response PDU is invalid: %j`,
+ validate?.errors
+ )
// OCPPError usage here is debatable: it's an error in the OCPP stack but not targeted to sendError().
throw new OCPPError(
- OCPPServiceUtils.ajvErrorsToErrorType(validate.errors),
+ OCPPServiceUtils.ajvErrorsToErrorType(validate?.errors),
'Response PDU is invalid',
commandName,
- JSON.stringify(validate.errors, null, 2)
- );
+ JSON.stringify(validate?.errors, undefined, 2)
+ )
}
- private async internalSendMessage(
+ private async internalSendMessage (
chargingStation: ChargingStation,
messageId: string,
messagePayload: JsonType | OCPPError,
messageType: MessageType,
- commandName?: RequestCommand | IncomingRequestCommand,
- params: RequestParams = {
- skipBufferingOnError: false,
- triggerMessage: false,
- }
+ commandName: RequestCommand | IncomingRequestCommand,
+ params?: RequestParams
): Promise<ResponseType> {
+ params = {
+ ...defaultRequestParams,
+ ...params
+ }
if (
- (chargingStation.isInUnknownState() === true &&
- commandName === RequestCommand.BOOT_NOTIFICATION) ||
- (chargingStation.getOcppStrictCompliance() === false &&
- chargingStation.isInUnknownState() === true) ||
- chargingStation.isInAcceptedState() === true ||
- (chargingStation.isInPendingState() === true &&
+ (chargingStation.inUnknownState() && commandName === RequestCommand.BOOT_NOTIFICATION) ||
+ (chargingStation.stationInfo?.ocppStrictCompliance === false &&
+ chargingStation.inUnknownState()) ||
+ chargingStation.inAcceptedState() ||
+ (chargingStation.inPendingState() &&
(params.triggerMessage === true || messageType === MessageType.CALL_RESULT_MESSAGE))
) {
// eslint-disable-next-line @typescript-eslint/no-this-alias
- const self = this;
+ const self = this
// Send a message through wsConnection
- return Utils.promiseWithTimeout(
- new Promise((resolve, reject) => {
- const messageToSend = this.buildMessageToSend(
- chargingStation,
- messageId,
- messagePayload,
- messageType,
- commandName,
- responseCallback,
- errorCallback
- );
- if (chargingStation.getEnableStatistics() === true) {
- chargingStation.performanceStatistics.addRequestStatistic(commandName, messageType);
- }
- // Check if wsConnection opened
- if (chargingStation.isWebSocketConnectionOpened() === true) {
- // Yes: Send Message
- const beginId = PerformanceStatistics.beginMeasure(commandName as string);
- // FIXME: Handle sending error
- chargingStation.wsConnection.send(messageToSend);
- PerformanceStatistics.endMeasure(commandName as string, beginId);
- logger.debug(
- `${chargingStation.logPrefix()} >> Command '${commandName}' sent ${this.getMessageTypeString(
- messageType
- )} payload: ${messageToSend}`
- );
- } else if (params.skipBufferingOnError === false) {
- // Buffer it
- chargingStation.bufferMessage(messageToSend);
- const ocppError = new OCPPError(
- ErrorType.GENERIC_ERROR,
- `WebSocket closed for buffered message id '${messageId}' with content '${messageToSend}'`,
+ return await new Promise<ResponseType>((resolve, reject) => {
+ /**
+ * Function that will receive the request's response
+ *
+ * @param payload -
+ * @param requestPayload -
+ */
+ const responseCallback = (payload: JsonType, requestPayload: JsonType): void => {
+ if (chargingStation.stationInfo?.enableStatistics === true) {
+ chargingStation.performanceStatistics?.addRequestStatistic(
commandName,
- (messagePayload as JsonObject)?.details ?? {}
- );
- if (messageType === MessageType.CALL_MESSAGE) {
- // Reject it but keep the request in the cache
- return reject(ocppError);
- }
- return errorCallback(ocppError, false);
- } else {
- // Reject it
- return errorCallback(
- new OCPPError(
- ErrorType.GENERIC_ERROR,
- `WebSocket closed for non buffered message id '${messageId}' with content '${messageToSend}'`,
- commandName,
- (messagePayload as JsonObject)?.details ?? {}
- ),
- false
- );
+ MessageType.CALL_RESULT_MESSAGE
+ )
}
- // Response?
- if (messageType !== MessageType.CALL_MESSAGE) {
- // Yes: send Ok
- return resolve(messagePayload);
+ // Handle the request's response
+ self.ocppResponseService
+ .responseHandler(
+ chargingStation,
+ commandName as RequestCommand,
+ payload,
+ requestPayload
+ )
+ .then(() => {
+ resolve(payload)
+ })
+ .catch(reject)
+ .finally(() => {
+ chargingStation.requests.delete(messageId)
+ chargingStation.emit(ChargingStationEvents.updated)
+ })
+ }
+
+ /**
+ * Function that will receive the request's error response
+ *
+ * @param ocppError -
+ * @param requestStatistic -
+ */
+ const errorCallback = (ocppError: OCPPError, requestStatistic = true): void => {
+ if (requestStatistic && chargingStation.stationInfo?.enableStatistics === true) {
+ chargingStation.performanceStatistics?.addRequestStatistic(
+ commandName,
+ MessageType.CALL_ERROR_MESSAGE
+ )
}
+ logger.error(
+ `${chargingStation.logPrefix()} Error occurred at ${OCPPServiceUtils.getMessageTypeString(
+ messageType
+ )} command ${commandName} with PDU %j:`,
+ messagePayload,
+ ocppError
+ )
+ chargingStation.requests.delete(messageId)
+ chargingStation.emit(ChargingStationEvents.updated)
+ reject(ocppError)
+ }
- /**
- * Function that will receive the request's response
- *
- * @param payload -
- * @param requestPayload -
- */
- function responseCallback(payload: JsonType, requestPayload: JsonType): void {
- if (chargingStation.getEnableStatistics() === true) {
- chargingStation.performanceStatistics.addRequestStatistic(
- commandName,
- MessageType.CALL_RESULT_MESSAGE
- );
- }
- // Handle the request's response
- self.ocppResponseService
- .responseHandler(
+ const handleSendError = (ocppError: OCPPError): void => {
+ if (params?.skipBufferingOnError === false) {
+ // Buffer
+ chargingStation.bufferMessage(messageToSend)
+ if (messageType === MessageType.CALL_MESSAGE) {
+ this.cacheRequestPromise(
chargingStation,
- commandName as RequestCommand,
- payload,
- requestPayload
+ messageId,
+ messagePayload as JsonType,
+ commandName,
+ responseCallback,
+ errorCallback
)
- .then(() => {
- resolve(payload);
- })
- .catch((error) => {
- reject(error);
- })
- .finally(() => {
- chargingStation.requests.delete(messageId);
- });
+ }
+ } else if (
+ params?.skipBufferingOnError === true &&
+ messageType === MessageType.CALL_MESSAGE
+ ) {
+ // Remove request from the cache
+ chargingStation.requests.delete(messageId)
}
+ reject(ocppError)
+ }
- /**
- * Function that will receive the request's error response
- *
- * @param error -
- * @param requestStatistic -
- */
- function errorCallback(error: OCPPError, requestStatistic = true): void {
- if (requestStatistic === true && chargingStation.getEnableStatistics() === true) {
- chargingStation.performanceStatistics.addRequestStatistic(
+ if (chargingStation.stationInfo?.enableStatistics === true) {
+ chargingStation.performanceStatistics?.addRequestStatistic(commandName, messageType)
+ }
+ const messageToSend = this.buildMessageToSend(
+ chargingStation,
+ messageId,
+ messagePayload,
+ messageType,
+ commandName
+ )
+ // Check if wsConnection opened
+ if (chargingStation.isWebSocketConnectionOpened()) {
+ const beginId = PerformanceStatistics.beginMeasure(commandName)
+ const sendTimeout = setTimeout(() => {
+ handleSendError(
+ new OCPPError(
+ ErrorType.GENERIC_ERROR,
+ `Timeout ${formatDurationMilliSeconds(
+ OCPPConstants.OCPP_WEBSOCKET_TIMEOUT
+ )} reached for ${
+ params?.skipBufferingOnError === false ? '' : 'non '
+ }buffered message id '${messageId}' with content '${messageToSend}'`,
commandName,
- MessageType.CALL_ERROR_MESSAGE
- );
+ (messagePayload as OCPPError).details
+ )
+ )
+ }, OCPPConstants.OCPP_WEBSOCKET_TIMEOUT)
+ chargingStation.wsConnection?.send(messageToSend, (error?: Error) => {
+ PerformanceStatistics.endMeasure(commandName, beginId)
+ clearTimeout(sendTimeout)
+ if (error == null) {
+ logger.debug(
+ `${chargingStation.logPrefix()} >> Command '${commandName}' sent ${OCPPServiceUtils.getMessageTypeString(
+ messageType
+ )} payload: ${messageToSend}`
+ )
+ if (messageType === MessageType.CALL_MESSAGE) {
+ this.cacheRequestPromise(
+ chargingStation,
+ messageId,
+ messagePayload as JsonType,
+ commandName,
+ responseCallback,
+ errorCallback
+ )
+ } else {
+ // Resolve response
+ resolve(messagePayload)
+ }
+ } else {
+ handleSendError(
+ new OCPPError(
+ ErrorType.GENERIC_ERROR,
+ `WebSocket errored for ${
+ params?.skipBufferingOnError === false ? '' : 'non '
+ }buffered message id '${messageId}' with content '${messageToSend}'`,
+ commandName,
+ { name: error.name, message: error.message, stack: error.stack }
+ )
+ )
}
- logger.error(
- `${chargingStation.logPrefix()} Error occurred when calling command ${commandName} with message data ${JSON.stringify(
- messagePayload
- )}:`,
- error
- );
- chargingStation.requests.delete(messageId);
- reject(error);
- }
- }),
- Constants.OCPP_WEBSOCKET_TIMEOUT,
- new OCPPError(
- ErrorType.GENERIC_ERROR,
- `Timeout for message id '${messageId}'`,
- commandName,
- (messagePayload as JsonObject)?.details ?? {}
- ),
- () => {
- messageType === MessageType.CALL_MESSAGE && chargingStation.requests.delete(messageId);
+ })
+ } else {
+ handleSendError(
+ new OCPPError(
+ ErrorType.GENERIC_ERROR,
+ `WebSocket closed for ${
+ params?.skipBufferingOnError === false ? '' : 'non '
+ }buffered message id '${messageId}' with content '${messageToSend}'`,
+ commandName,
+ (messagePayload as OCPPError).details
+ )
+ )
}
- );
+ })
}
throw new OCPPError(
ErrorType.SECURITY_ERROR,
- `Cannot send command ${commandName} PDU when the charging station is in ${chargingStation.getRegistrationStatus()} state on the central server`,
+ `Cannot send command ${commandName} PDU when the charging station is in ${chargingStation.bootNotificationResponse?.status} state on the central server`,
commandName
- );
+ )
}
- private buildMessageToSend(
+ private buildMessageToSend (
chargingStation: ChargingStation,
messageId: string,
messagePayload: JsonType | OCPPError,
messageType: MessageType,
- commandName?: RequestCommand | IncomingRequestCommand,
- responseCallback?: ResponseCallback,
- errorCallback?: ErrorCallback
+ commandName: RequestCommand | IncomingRequestCommand
): string {
- let messageToSend: string;
+ let messageToSend: string
// Type of message
switch (messageType) {
// Request
case MessageType.CALL_MESSAGE:
// Build request
- chargingStation.requests.set(messageId, [
- responseCallback,
- errorCallback,
- commandName,
- messagePayload as JsonType,
- ]);
- this.validateRequestPayload(chargingStation, commandName, messagePayload as JsonObject);
+ this.validateRequestPayload(chargingStation, commandName, messagePayload as JsonType)
messageToSend = JSON.stringify([
messageType,
messageId,
- commandName,
- messagePayload,
- ] as OutgoingRequest);
- break;
+ commandName as RequestCommand,
+ messagePayload as JsonType
+ ] satisfies OutgoingRequest)
+ break
// Response
case MessageType.CALL_RESULT_MESSAGE:
// Build response
this.validateIncomingRequestResponsePayload(
chargingStation,
commandName,
- messagePayload as JsonObject
- );
- messageToSend = JSON.stringify([messageType, messageId, messagePayload] as Response);
- break;
+ messagePayload as JsonType
+ )
+ messageToSend = JSON.stringify([
+ messageType,
+ messageId,
+ messagePayload as JsonType
+ ] satisfies Response)
+ break
// Error Message
case MessageType.CALL_ERROR_MESSAGE:
// Build Error Message
messageToSend = JSON.stringify([
messageType,
messageId,
- (messagePayload as OCPPError)?.code ?? ErrorType.GENERIC_ERROR,
- (messagePayload as OCPPError)?.message ?? '',
- (messagePayload as OCPPError)?.details ?? { commandName },
- ] as ErrorResponse);
- break;
- }
- return messageToSend;
- }
-
- private getMessageTypeString(messageType: MessageType): string {
- switch (messageType) {
- case MessageType.CALL_MESSAGE:
- return 'request';
- case MessageType.CALL_RESULT_MESSAGE:
- return 'response';
- case MessageType.CALL_ERROR_MESSAGE:
- return 'error';
+ (messagePayload as OCPPError).code,
+ (messagePayload as OCPPError).message,
+ (messagePayload as OCPPError).details ?? {
+ command: (messagePayload as OCPPError).command
+ }
+ ] satisfies ErrorResponse)
+ break
}
+ return messageToSend
}
- private handleSendMessageError(
+ private cacheRequestPromise (
chargingStation: ChargingStation,
+ messageId: string,
+ messagePayload: JsonType,
commandName: RequestCommand | IncomingRequestCommand,
- error: Error,
- params: HandleErrorParams<EmptyObject> = { throwError: false }
+ responseCallback: ResponseCallback,
+ errorCallback: ErrorCallback
): void {
- logger.error(`${chargingStation.logPrefix()} Request command '${commandName}' error:`, error);
- if (params?.throwError === true) {
- throw error;
- }
+ chargingStation.requests.set(messageId, [
+ responseCallback,
+ errorCallback,
+ commandName,
+ messagePayload
+ ])
}
// eslint-disable-next-line @typescript-eslint/no-unused-vars
public abstract requestHandler<ReqType extends JsonType, ResType extends JsonType>(
chargingStation: ChargingStation,
commandName: RequestCommand,
+ // FIXME: should be ReqType
commandParams?: JsonType,
params?: RequestParams
- ): Promise<ResType>;
+ ): Promise<ResType>
}