Implement singleton design pattern with strict null check

[e-mobility-charging-stations-simulator.git] / src / charging-station / ocpp / OCPPResponseService.ts

diff --git a/src/charging-station/ocpp/OCPPResponseService.ts b/src/charging-station/ocpp/OCPPResponseService.ts
index c0dd3f767ea14ff8546195556c48daf3aec3dc0c..624659aeec5e18cb78a6c5dd31d498ce2648489d 100644 (file)
--- a/src/charging-station/ocpp/OCPPResponseService.ts
+++ b/src/charging-station/ocpp/OCPPResponseService.ts
@@ -1,21 +1,64 @@
-import type ChargingStation from '../ChargingStation';
+import { JSONSchemaType } from 'ajv';
+import Ajv from 'ajv-draft-04';
+import ajvFormats from 'ajv-formats';
+
+import OCPPError from '../../exception/OCPPError';
 import { JsonType } from '../../types/JsonType';
 import { RequestCommand } from '../../types/ocpp/Requests';
+import logger from '../../utils/Logger';
+import type ChargingStation from '../ChargingStation';
+import { OCPPServiceUtils } from './OCPPServiceUtils';
+
+const moduleName = 'OCPPResponseService';
 
 export default abstract class OCPPResponseService {
-  private static readonly instances: Map<string, OCPPResponseService> = new Map<string, OCPPResponseService>();
-  protected readonly chargingStation: ChargingStation;
+  private static instance: OCPPResponseService | null = null;
+  private ajv: Ajv;
 
-  protected constructor(chargingStation: ChargingStation) {
-    this.chargingStation = chargingStation;
+  protected constructor() {
+    this.ajv = new Ajv();
+    ajvFormats(this.ajv);
   }
 
-  public static getInstance<T extends OCPPResponseService>(this: new (chargingStation: ChargingStation) => T, chargingStation: ChargingStation): T {
-    if (!OCPPResponseService.instances.has(chargingStation.id)) {
-      OCPPResponseService.instances.set(chargingStation.id, new this(chargingStation));
+  public static getInstance<T extends OCPPResponseService>(this: new () => T): T {
+    if (OCPPResponseService.instance === null) {
+      OCPPResponseService.instance = new this();
     }
-    return OCPPResponseService.instances.get(chargingStation.id) as T;
+    return OCPPResponseService.instance as T;
   }
 
-  public abstract handleResponse(commandName: RequestCommand, payload: JsonType | string, requestPayload: JsonType): Promise<void>;
+  protected validateResponsePayload<T extends JsonType>(
+    chargingStation: ChargingStation,
+    commandName: RequestCommand,
+    schema: JSONSchemaType<T>,
+    payload: T
+  ): boolean {
+    if (!chargingStation.getPayloadSchemaValidation()) {
+      return true;
+    }
+    const validate = this.ajv.compile(schema);
+    if (validate(payload)) {
+      return true;
+    }
+    logger.error(
+      `${chargingStation.logPrefix()} ${moduleName}.validateResponsePayload: Response PDU is invalid: %j`,
+      validate.errors
+    );
+    throw new OCPPError(
+      OCPPServiceUtils.ajvErrorsToErrorType(validate.errors),
+      'Response PDU is invalid',
+      commandName,
+      JSON.stringify(validate.errors, null, 2)
+    );
+  }
+
+  // eslint-disable-next-line @typescript-eslint/no-empty-function
+  protected emptyResponseHandler() {}
+
+  public abstract responseHandler(
+    chargingStation: ChargingStation,
+    commandName: RequestCommand,
+    payload: JsonType,
+    requestPayload: JsonType
+  ): Promise<void>;
 }