X-Git-Url: https://git.piment-noir.org/?a=blobdiff_plain;f=src%2Fcharging-station%2FBootstrap.ts;h=5b23676f24e39049cedf24f7581132f5b265a925;hb=401fa922baa555f5997732052918ae2ab5ff184c;hp=1550f6a7dc8ee92547fda280dbe4f569592f753e;hpb=34c200d5d7239aed80b68da98b664b573bf6e8bd;p=e-mobility-charging-stations-simulator.git

diff --git a/src/charging-station/Bootstrap.ts b/src/charging-station/Bootstrap.ts
index 1550f6a7..5b23676f 100644
--- a/src/charging-station/Bootstrap.ts
+++ b/src/charging-station/Bootstrap.ts
@@ -1,29 +1,33 @@
 // Partial Copyright Jerome Benoit. 2021-2023. All Rights Reserved.
 
-import { EventEmitter } from 'node:events';
-import { dirname, extname, join } from 'node:path';
-import { fileURLToPath } from 'node:url';
-import { isMainThread } from 'node:worker_threads';
+import { EventEmitter } from 'node:events'
+import { dirname, extname, join } from 'node:path'
+import process, { exit } from 'node:process'
+import { fileURLToPath } from 'node:url'
 
-import chalk from 'chalk';
-import { availableParallelism } from 'poolifier';
+import chalk from 'chalk'
+import { availableParallelism } from 'poolifier'
 
-import { waitChargingStationEvents } from './ChargingStationUtils';
-import type { AbstractUIServer } from './ui-server/AbstractUIServer';
-import { UIServerFactory } from './ui-server/UIServerFactory';
-import { version } from '../../package.json' assert { type: 'json' };
-import { BaseError } from '../exception';
-import { type Storage, StorageFactory } from '../performance';
+import { waitChargingStationEvents } from './Helpers.js'
+import type { AbstractUIServer } from './ui-server/AbstractUIServer.js'
+import { UIServerFactory } from './ui-server/UIServerFactory.js'
+import { version } from '../../package.json'
+import { BaseError } from '../exception/index.js'
+import { type Storage, StorageFactory } from '../performance/index.js'
 import {
   type ChargingStationData,
   type ChargingStationWorkerData,
   type ChargingStationWorkerMessage,
   type ChargingStationWorkerMessageData,
   ChargingStationWorkerMessageEvents,
+  ConfigurationSection,
   ProcedureName,
   type StationTemplateUrl,
   type Statistics,
-} from '../types';
+  type StorageConfiguration,
+  type UIServerConfiguration,
+  type WorkerConfiguration
+} from '../types/index.js'
 import {
   Configuration,
   Constants,
@@ -32,96 +36,110 @@ import {
   handleUncaughtException,
   handleUnhandledRejection,
   isNotEmptyArray,
-  isNullOrUndefined,
   logPrefix,
-  logger,
-} from '../utils';
-import { type WorkerAbstract, WorkerConstants, WorkerFactory } from '../worker';
+  logger
+} from '../utils/index.js'
+import { type WorkerAbstract, WorkerFactory } from '../worker/index.js'
 
-const moduleName = 'Bootstrap';
+const moduleName = 'Bootstrap'
 
 enum exitCodes {
+  succeeded = 0,
   missingChargingStationsConfiguration = 1,
   noChargingStationTemplates = 2,
+  gracefulShutdownError = 3,
 }
 
 export class Bootstrap extends EventEmitter {
-  private static instance: Bootstrap | null = null;
-  public numberOfChargingStations!: number;
-  public numberOfChargingStationTemplates!: number;
-  private workerImplementation: WorkerAbstract<ChargingStationWorkerData> | null;
-  private readonly uiServer!: AbstractUIServer | null;
-  private readonly storage!: Storage;
-  private numberOfStartedChargingStations!: number;
-  private readonly version: string = version;
-  private initializedCounters: boolean;
-  private started: boolean;
-  private starting: boolean;
-  private stopping: boolean;
-  private readonly workerScript: string;
+  private static instance: Bootstrap | null = null
+  public numberOfChargingStations!: number
+  public numberOfChargingStationTemplates!: number
+  private workerImplementation?: WorkerAbstract<ChargingStationWorkerData>
+  private readonly uiServer?: AbstractUIServer
+  private storage?: Storage
+  private numberOfStartedChargingStations!: number
+  private readonly version: string = version
+  private initializedCounters: boolean
+  private started: boolean
+  private starting: boolean
+  private stopping: boolean
 
-  private constructor() {
-    super();
+  private constructor () {
+    super()
     for (const signal of ['SIGINT', 'SIGQUIT', 'SIGTERM']) {
-      process.on(signal, this.gracefulShutdown);
+      process.on(signal, this.gracefulShutdown.bind(this))
     }
     // Enable unconditionally for now
-    handleUnhandledRejection();
-    handleUncaughtException();
-    this.started = false;
-    this.starting = false;
-    this.stopping = false;
-    this.initializedCounters = false;
-    this.initializeCounters();
-    this.workerImplementation = null;
-    this.workerScript = join(
-      dirname(fileURLToPath(import.meta.url)),
-      `ChargingStationWorker${extname(fileURLToPath(import.meta.url))}`,
-    );
-    Configuration.getUIServer().enabled === true &&
-      (this.uiServer = UIServerFactory.getUIServerImplementation(Configuration.getUIServer()));
-    Configuration.getPerformanceStorage().enabled === true &&
-      (this.storage = StorageFactory.getStorage(
-        Configuration.getPerformanceStorage().type,
-        Configuration.getPerformanceStorage().uri,
-        this.logPrefix(),
-      ));
-    Configuration.setConfigurationChangeCallback(async () => Bootstrap.getInstance().restart());
+    handleUnhandledRejection()
+    handleUncaughtException()
+    this.started = false
+    this.starting = false
+    this.stopping = false
+    this.initializedCounters = false
+    this.initializeCounters()
+    this.uiServer = UIServerFactory.getUIServerImplementation(
+      Configuration.getConfigurationSection<UIServerConfiguration>(ConfigurationSection.uiServer)
+    )
+    Configuration.configurationChangeCallback = async () => {
+      await Bootstrap.getInstance().restart(false)
+    }
   }
 
-  public static getInstance(): Bootstrap {
+  public static getInstance (): Bootstrap {
     if (Bootstrap.instance === null) {
-      Bootstrap.instance = new Bootstrap();
+      Bootstrap.instance = new Bootstrap()
     }
-    return Bootstrap.instance;
+    return Bootstrap.instance
   }
 
-  public async start(): Promise<void> {
-    if (!isMainThread) {
-      throw new Error('Cannot start charging stations simulator from worker thread');
-    }
-    if (this.started === false) {
-      if (this.starting === false) {
-        this.starting = true;
-        this.initializeCounters();
-        this.initializeWorkerImplementation();
-        await this.workerImplementation?.start();
-        await this.storage?.open();
-        this.uiServer?.start();
+  public async start (): Promise<void> {
+    if (!this.started) {
+      if (!this.starting) {
+        this.starting = true
+        this.on(ChargingStationWorkerMessageEvents.started, this.workerEventStarted)
+        this.on(ChargingStationWorkerMessageEvents.stopped, this.workerEventStopped)
+        this.on(ChargingStationWorkerMessageEvents.updated, this.workerEventUpdated)
+        this.on(
+          ChargingStationWorkerMessageEvents.performanceStatistics,
+          this.workerEventPerformanceStatistics
+        )
+        this.initializeCounters()
+        const workerConfiguration = Configuration.getConfigurationSection<WorkerConfiguration>(
+          ConfigurationSection.worker
+        )
+        this.initializeWorkerImplementation(workerConfiguration)
+        await this.workerImplementation?.start()
+        const performanceStorageConfiguration =
+          Configuration.getConfigurationSection<StorageConfiguration>(
+            ConfigurationSection.performanceStorage
+          )
+        if (performanceStorageConfiguration.enabled === true) {
+          this.storage = StorageFactory.getStorage(
+            // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+            performanceStorageConfiguration.type!,
+            // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+            performanceStorageConfiguration.uri!,
+            this.logPrefix()
+          )
+          await this.storage?.open()
+        }
+        Configuration.getConfigurationSection<UIServerConfiguration>(ConfigurationSection.uiServer)
+          .enabled === true && this.uiServer?.start()
         // Start ChargingStation object instance in worker thread
-        for (const stationTemplateUrl of Configuration.getStationTemplateUrls()) {
+        // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+        for (const stationTemplateUrl of Configuration.getStationTemplateUrls()!) {
           try {
-            const nbStations = stationTemplateUrl.numberOfStations ?? 0;
+            const nbStations = stationTemplateUrl.numberOfStations ?? 0
             for (let index = 1; index <= nbStations; index++) {
-              await this.startChargingStation(index, stationTemplateUrl);
+              await this.startChargingStation(index, stationTemplateUrl)
             }
           } catch (error) {
             console.error(
               chalk.red(
-                `Error at starting charging station with template file ${stationTemplateUrl.file}: `,
+                `Error at starting charging station with template file ${stationTemplateUrl.file}: `
               ),
-              error,
-            );
+              error
+            )
           }
         }
         console.info(
@@ -130,226 +148,256 @@ export class Bootstrap extends EventEmitter {
               this.version
             } started with ${this.numberOfChargingStations.toString()} charging station(s) from ${this.numberOfChargingStationTemplates.toString()} configured charging station template(s) and ${
               Configuration.workerDynamicPoolInUse()
-                ? `${Configuration.getWorker().poolMinSize?.toString()}/`
+                ? `${workerConfiguration.poolMinSize?.toString()}/`
                 : ''
             }${this.workerImplementation?.size}${
               Configuration.workerPoolInUse()
-                ? `/${Configuration.getWorker().poolMaxSize?.toString()}`
+                ? `/${workerConfiguration.poolMaxSize?.toString()}`
                 : ''
-            } worker(s) concurrently running in '${Configuration.getWorker().processType}' mode${
-              !isNullOrUndefined(this.workerImplementation?.maxElementsPerWorker)
+            } worker(s) concurrently running in '${workerConfiguration.processType}' mode${
+              this.workerImplementation?.maxElementsPerWorker != null
                 ? ` (${this.workerImplementation?.maxElementsPerWorker} charging station(s) per worker)`
                 : ''
-            }`,
-          ),
-        );
+            }`
+          )
+        )
         Configuration.workerDynamicPoolInUse() &&
           console.warn(
             chalk.yellow(
-              'Charging stations simulator is using dynamic pool mode. This is an experimental feature with known issues.\nPlease consider using static pool or worker set mode instead',
-            ),
-          );
-        console.info(chalk.green('Worker set/pool information:'), this.workerImplementation?.info);
-        this.started = true;
-        this.starting = false;
+              'Charging stations simulator is using dynamic pool mode. This is an experimental feature with known issues.\nPlease consider using fixed pool or worker set mode instead'
+            )
+          )
+        console.info(chalk.green('Worker set/pool information:'), this.workerImplementation?.info)
+        this.started = true
+        this.starting = false
       } else {
-        console.error(chalk.red('Cannot start an already starting charging stations simulator'));
+        console.error(chalk.red('Cannot start an already starting charging stations simulator'))
       }
     } else {
-      console.error(chalk.red('Cannot start an already started charging stations simulator'));
+      console.error(chalk.red('Cannot start an already started charging stations simulator'))
     }
   }
 
-  public async stop(): Promise<void> {
-    if (!isMainThread) {
-      throw new Error('Cannot stop charging stations simulator from worker thread');
-    }
-    if (this.started === true) {
-      if (this.stopping === false) {
-        this.stopping = true;
-        await this.uiServer?.sendInternalRequest(
-          this.uiServer.buildProtocolRequest(
-            generateUUID(),
-            ProcedureName.STOP_CHARGING_STATION,
-            Constants.EMPTY_FREEZED_OBJECT,
-          ),
-        );
-        await Promise.race([
-          waitChargingStationEvents(
-            this,
-            ChargingStationWorkerMessageEvents.stopped,
-            this.numberOfChargingStations,
-          ),
-          new Promise<string>((resolve) => {
-            setTimeout(() => {
-              const message = `Timeout reached ${formatDurationMilliSeconds(
-                Constants.STOP_SIMULATOR_TIMEOUT,
-              )} at stopping charging stations simulator`;
-              console.warn(chalk.yellow(message));
-              resolve(message);
-            }, Constants.STOP_SIMULATOR_TIMEOUT);
-          }),
-        ]);
-        await this.workerImplementation?.stop();
-        this.workerImplementation = null;
-        this.uiServer?.stop();
-        await this.storage?.close();
-        this.resetCounters();
-        this.initializedCounters = false;
-        this.started = false;
-        this.stopping = false;
+  public async stop (stopChargingStations = true): Promise<void> {
+    if (this.started) {
+      if (!this.stopping) {
+        this.stopping = true
+        if (stopChargingStations) {
+          await this.uiServer?.sendInternalRequest(
+            this.uiServer.buildProtocolRequest(
+              generateUUID(),
+              ProcedureName.STOP_CHARGING_STATION,
+              Constants.EMPTY_FROZEN_OBJECT
+            )
+          )
+          try {
+            await this.waitChargingStationsStopped()
+          } catch (error) {
+            console.error(chalk.red('Error while waiting for charging stations to stop: '), error)
+          }
+        }
+        await this.workerImplementation?.stop()
+        delete this.workerImplementation
+        this.removeAllListeners()
+        await this.storage?.close()
+        delete this.storage
+        this.resetCounters()
+        this.initializedCounters = false
+        this.started = false
+        this.stopping = false
       } else {
-        console.error(chalk.red('Cannot stop an already stopping charging stations simulator'));
+        console.error(chalk.red('Cannot stop an already stopping charging stations simulator'))
       }
     } else {
-      console.error(chalk.red('Cannot stop an already stopped charging stations simulator'));
+      console.error(chalk.red('Cannot stop an already stopped charging stations simulator'))
     }
   }
 
-  public async restart(): Promise<void> {
-    await this.stop();
-    await this.start();
+  public async restart (stopChargingStations?: boolean): Promise<void> {
+    await this.stop(stopChargingStations)
+    Configuration.getConfigurationSection<UIServerConfiguration>(ConfigurationSection.uiServer)
+      .enabled === false && this.uiServer?.stop()
+    await this.start()
+  }
+
+  private async waitChargingStationsStopped (): Promise<string> {
+    return await new Promise<string>((resolve, reject) => {
+      const waitTimeout = setTimeout(() => {
+        const message = `Timeout ${formatDurationMilliSeconds(
+          Constants.STOP_CHARGING_STATIONS_TIMEOUT
+        )} reached at stopping charging stations`
+        console.warn(chalk.yellow(message))
+        reject(new Error(message))
+      }, Constants.STOP_CHARGING_STATIONS_TIMEOUT)
+      waitChargingStationEvents(
+        this,
+        ChargingStationWorkerMessageEvents.stopped,
+        this.numberOfChargingStations
+      )
+        .then(() => {
+          resolve('Charging stations stopped')
+        })
+        .catch(reject)
+        .finally(() => {
+          clearTimeout(waitTimeout)
+        })
+    })
   }
 
-  private initializeWorkerImplementation(): void {
-    let elementsPerWorker: number;
-    if (Configuration.getWorker()?.elementsPerWorker === 'auto') {
-      elementsPerWorker =
-        this.numberOfChargingStations > availableParallelism()
-          ? Math.round(this.numberOfChargingStations / availableParallelism())
-          : 1;
+  private initializeWorkerImplementation (workerConfiguration: WorkerConfiguration): void {
+    let elementsPerWorker: number | undefined
+    switch (workerConfiguration?.elementsPerWorker) {
+      case 'auto':
+        elementsPerWorker =
+          this.numberOfChargingStations > availableParallelism()
+            ? Math.round(this.numberOfChargingStations / (availableParallelism() * 1.5))
+            : 1
+        break
+      case 'all':
+        elementsPerWorker = this.numberOfChargingStations
+        break
     }
-    this.workerImplementation === null &&
-      (this.workerImplementation = WorkerFactory.getWorkerImplementation<ChargingStationWorkerData>(
-        this.workerScript,
-        Configuration.getWorker().processType,
-        {
-          workerStartDelay: Configuration.getWorker().startDelay,
-          elementStartDelay: Configuration.getWorker().elementStartDelay,
-          poolMaxSize: Configuration.getWorker().poolMaxSize,
-          poolMinSize: Configuration.getWorker().poolMinSize,
-          elementsPerWorker:
-            elementsPerWorker ?? (Configuration.getWorker().elementsPerWorker as number),
-          poolOptions: {
-            workerChoiceStrategy: Configuration.getWorker().poolStrategy,
-            messageHandler: this.messageHandler.bind(this) as (message: unknown) => void,
-          },
-        },
-      ));
+    this.workerImplementation = WorkerFactory.getWorkerImplementation<ChargingStationWorkerData>(
+      join(
+        dirname(fileURLToPath(import.meta.url)),
+        `ChargingStationWorker${extname(fileURLToPath(import.meta.url))}`
+      ),
+      // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+      workerConfiguration.processType!,
+      {
+        workerStartDelay: workerConfiguration.startDelay,
+        elementStartDelay: workerConfiguration.elementStartDelay,
+        // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+        poolMaxSize: workerConfiguration.poolMaxSize!,
+        // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+        poolMinSize: workerConfiguration.poolMinSize!,
+        elementsPerWorker: elementsPerWorker ?? (workerConfiguration.elementsPerWorker as number),
+        poolOptions: {
+          messageHandler: this.messageHandler.bind(this) as (message: unknown) => void,
+          workerOptions: { resourceLimits: workerConfiguration.resourceLimits }
+        }
+      }
+    )
   }
 
-  private messageHandler(
-    msg: ChargingStationWorkerMessage<ChargingStationWorkerMessageData>,
+  private messageHandler (
+    msg: ChargingStationWorkerMessage<ChargingStationWorkerMessageData>
   ): void {
     // logger.debug(
     //   `${this.logPrefix()} ${moduleName}.messageHandler: Worker channel message received: ${JSON.stringify(
     //     msg,
-    //     null,
+    //     undefined,
     //     2
     //   )}`
-    // );
+    // )
     try {
-      switch (msg.id) {
+      switch (msg.event) {
         case ChargingStationWorkerMessageEvents.started:
-          this.workerEventStarted(msg.data as ChargingStationData);
-          this.emit(ChargingStationWorkerMessageEvents.started, msg.data as ChargingStationData);
-          break;
+          this.emit(ChargingStationWorkerMessageEvents.started, msg.data as ChargingStationData)
+          break
         case ChargingStationWorkerMessageEvents.stopped:
-          this.workerEventStopped(msg.data as ChargingStationData);
-          this.emit(ChargingStationWorkerMessageEvents.stopped, msg.data as ChargingStationData);
-          break;
+          this.emit(ChargingStationWorkerMessageEvents.stopped, msg.data as ChargingStationData)
+          break
         case ChargingStationWorkerMessageEvents.updated:
-          this.workerEventUpdated(msg.data as ChargingStationData);
-          this.emit(ChargingStationWorkerMessageEvents.updated, msg.data as ChargingStationData);
-          break;
+          this.emit(ChargingStationWorkerMessageEvents.updated, msg.data as ChargingStationData)
+          break
         case ChargingStationWorkerMessageEvents.performanceStatistics:
-          this.workerEventPerformanceStatistics(msg.data as Statistics);
           this.emit(
             ChargingStationWorkerMessageEvents.performanceStatistics,
-            msg.data as Statistics,
-          );
-          break;
+            msg.data as Statistics
+          )
+          break
+        case ChargingStationWorkerMessageEvents.startWorkerElementError:
+          logger.error(
+            `${this.logPrefix()} ${moduleName}.messageHandler: Error occured while starting worker element:`,
+            msg.data
+          )
+          this.emit(ChargingStationWorkerMessageEvents.startWorkerElementError, msg.data)
+          break
+        case ChargingStationWorkerMessageEvents.startedWorkerElement:
+          break
         default:
           throw new BaseError(
-            `Unknown event type: '${msg.id}' for data: ${JSON.stringify(msg.data, null, 2)}`,
-          );
+            `Unknown charging station worker event: '${
+              msg.event
+            }' received with data: ${JSON.stringify(msg.data, undefined, 2)}`
+          )
       }
     } catch (error) {
       logger.error(
         `${this.logPrefix()} ${moduleName}.messageHandler: Error occurred while handling '${
-          msg.id
+          msg.event
         }' event:`,
-        error,
-      );
+        error
+      )
     }
   }
 
-  private workerEventStarted = (data: ChargingStationData) => {
-    this.uiServer?.chargingStations.set(data.stationInfo.hashId, data);
-    ++this.numberOfStartedChargingStations;
+  private readonly workerEventStarted = (data: ChargingStationData): void => {
+    this.uiServer?.chargingStations.set(data.stationInfo.hashId, data)
+    ++this.numberOfStartedChargingStations
     logger.info(
       `${this.logPrefix()} ${moduleName}.workerEventStarted: Charging station ${
         data.stationInfo.chargingStationId
       } (hashId: ${data.stationInfo.hashId}) started (${
         this.numberOfStartedChargingStations
-      } started from ${this.numberOfChargingStations})`,
-    );
-  };
+      } started from ${this.numberOfChargingStations})`
+    )
+  }
 
-  private workerEventStopped = (data: ChargingStationData) => {
-    this.uiServer?.chargingStations.set(data.stationInfo.hashId, data);
-    --this.numberOfStartedChargingStations;
+  private readonly workerEventStopped = (data: ChargingStationData): void => {
+    this.uiServer?.chargingStations.set(data.stationInfo.hashId, data)
+    --this.numberOfStartedChargingStations
     logger.info(
       `${this.logPrefix()} ${moduleName}.workerEventStopped: Charging station ${
         data.stationInfo.chargingStationId
       } (hashId: ${data.stationInfo.hashId}) stopped (${
         this.numberOfStartedChargingStations
-      } started from ${this.numberOfChargingStations})`,
-    );
-  };
+      } started from ${this.numberOfChargingStations})`
+    )
+  }
 
-  private workerEventUpdated = (data: ChargingStationData) => {
-    this.uiServer?.chargingStations.set(data.stationInfo.hashId, data);
-  };
+  private readonly workerEventUpdated = (data: ChargingStationData): void => {
+    this.uiServer?.chargingStations.set(data.stationInfo.hashId, data)
+  }
 
-  private workerEventPerformanceStatistics = (data: Statistics) => {
-    this.storage.storePerformanceStatistics(data) as void;
-  };
+  private readonly workerEventPerformanceStatistics = (data: Statistics): void => {
+    this.storage?.storePerformanceStatistics(data) as undefined
+  }
 
-  private initializeCounters() {
-    if (this.initializedCounters === false) {
-      this.resetCounters();
-      const stationTemplateUrls = Configuration.getStationTemplateUrls();
+  private initializeCounters (): void {
+    if (!this.initializedCounters) {
+      this.resetCounters()
+      // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+      const stationTemplateUrls = Configuration.getStationTemplateUrls()!
       if (isNotEmptyArray(stationTemplateUrls)) {
-        this.numberOfChargingStationTemplates = stationTemplateUrls.length;
+        this.numberOfChargingStationTemplates = stationTemplateUrls.length
         for (const stationTemplateUrl of stationTemplateUrls) {
-          this.numberOfChargingStations += stationTemplateUrl.numberOfStations ?? 0;
+          this.numberOfChargingStations += stationTemplateUrl.numberOfStations ?? 0
         }
       } else {
         console.warn(
-          chalk.yellow("'stationTemplateUrls' not defined or empty in configuration, exiting"),
-        );
-        process.exit(exitCodes.missingChargingStationsConfiguration);
+          chalk.yellow("'stationTemplateUrls' not defined or empty in configuration, exiting")
+        )
+        exit(exitCodes.missingChargingStationsConfiguration)
       }
       if (this.numberOfChargingStations === 0) {
-        console.warn(
-          chalk.yellow('No charging station template enabled in configuration, exiting'),
-        );
-        process.exit(exitCodes.noChargingStationTemplates);
+        console.warn(chalk.yellow('No charging station template enabled in configuration, exiting'))
+        exit(exitCodes.noChargingStationTemplates)
       }
-      this.initializedCounters = true;
+      this.initializedCounters = true
     }
   }
 
-  private resetCounters(): void {
-    this.numberOfChargingStationTemplates = 0;
-    this.numberOfChargingStations = 0;
-    this.numberOfStartedChargingStations = 0;
+  private resetCounters (): void {
+    this.numberOfChargingStationTemplates = 0
+    this.numberOfChargingStations = 0
+    this.numberOfStartedChargingStations = 0
   }
 
-  private async startChargingStation(
+  private async startChargingStation (
     index: number,
-    stationTemplateUrl: StationTemplateUrl,
+    stationTemplateUrl: StationTemplateUrl
   ): Promise<void> {
     await this.workerImplementation?.addElement({
       index,
@@ -357,24 +405,32 @@ export class Bootstrap extends EventEmitter {
         dirname(fileURLToPath(import.meta.url)),
         'assets',
         'station-templates',
-        stationTemplateUrl.file,
-      ),
-    });
+        stationTemplateUrl.file
+      )
+    })
   }
 
-  private gracefulShutdown = (): void => {
-    console.info(`${chalk.green('Graceful shutdown')}`);
+  private gracefulShutdown (): void {
     this.stop()
       .then(() => {
-        process.exit(0);
+        console.info(`${chalk.green('Graceful shutdown')}`)
+        this.uiServer?.stop()
+        // stop() asks for charging stations to stop by default
+        this.waitChargingStationsStopped()
+          .then(() => {
+            exit(exitCodes.succeeded)
+          })
+          .catch(() => {
+            exit(exitCodes.gracefulShutdownError)
+          })
       })
       .catch((error) => {
-        console.error(chalk.red('Error while shutdowning charging stations simulator: '), error);
-        process.exit(1);
-      });
-  };
+        console.error(chalk.red('Error while shutdowning charging stations simulator: '), error)
+        exit(exitCodes.gracefulShutdownError)
+      })
+  }
 
-  private logPrefix = (): string => {
-    return logPrefix(' Bootstrap |');
-  };
+  private readonly logPrefix = (): string => {
+    return logPrefix(' Bootstrap |')
+  }
 }