WIP - first shot of massive ddd-hexagon refactor

src/libs/api/api-error.response.ts

@@ -0,0 +1,19 @@
+export class ApiErrorResponse {
+  readonly statusCode: number;
+
+  readonly message: string;
+
+  readonly error: string;
+
+  readonly correlationId: string;
+
+  readonly subErrors?: string[];
+
+  constructor(body: ApiErrorResponse) {
+    this.statusCode = body.statusCode;
+    this.message = body.message;
+    this.error = body.error;
+    this.correlationId = body.correlationId;
+    this.subErrors = body.subErrors;
+  }
+}

src/libs/api/id.response.dto.ts

@@ -0,0 +1,7 @@
+export class IdResponse {
+  constructor(id: string) {
+    this.id = id;
+  }
+
+  readonly id: string;
+}

src/libs/api/paginated.response.base.ts

@@ -0,0 +1,8 @@
+import { Paginated } from '../ddd';
+
+export abstract class PaginatedResponseDto<T> extends Paginated<T> {
+  readonly count: number;
+  readonly limit: number;
+  readonly page: number;
+  abstract readonly data: readonly T[];
+}

src/libs/api/response.base.ts

@@ -0,0 +1,23 @@
+import { IdResponse } from './id.response.dto';
+
+export interface BaseResponseProps {
+  id: string;
+  createdAt: Date;
+  updatedAt: Date;
+}
+
+/**
+ * Most of our response objects will have properties like
+ * id, createdAt and updatedAt so we can move them to a
+ * separate class and extend it to avoid duplication.
+ */
+export class ResponseBase extends IdResponse {
+  constructor(props: BaseResponseProps) {
+    super(props.id);
+    this.createdAt = new Date(props.createdAt).toISOString();
+    this.updatedAt = new Date(props.updatedAt).toISOString();
+  }
+
+  readonly createdAt: string;
+  readonly updatedAt: string;
+}

src/libs/db/prisma-repository.base.ts

@@ -0,0 +1,46 @@
+import { EventEmitter2 } from '@nestjs/event-emitter';
+import { AggregateRoot, Mapper, RepositoryPort } from '../ddd';
+import { ObjectLiteral } from '../types';
+import { LoggerPort } from '../ports/logger.port';
+import { None, Option, Some } from 'oxide.ts';
+import { PrismaRepositoryPort } from '../ports/prisma-repository.port';
+
+export abstract class PrismaRepositoryBase<
+  Aggregate extends AggregateRoot<any>,
+  DbModel extends ObjectLiteral,
+> implements RepositoryPort<Aggregate>
+{
+  protected constructor(
+    protected readonly prisma: PrismaRepositoryPort<Aggregate> | any,
+    protected readonly mapper: Mapper<Aggregate, DbModel>,
+    protected readonly eventEmitter: EventEmitter2,
+    protected readonly logger: LoggerPort,
+  ) {}
+
+  async findOneById(uuid: string): Promise<Option<Aggregate>> {
+    try {
+      const entity = await this.prisma.findUnique({
+        where: { uuid },
+      });
+
+      return entity ? Some(this.mapper.toDomain(entity)) : None;
+    } catch (e) {
+      console.log('ouch on findOneById');
+    }
+  }
+
+  async insert(entity: Aggregate): Promise<void> {
+    try {
+      await this.prisma.create({
+        data: this.mapper.toPersistence(entity),
+      });
+    } catch (e) {
+      console.log(e);
+      console.log('ouch on insert');
+    }
+  }
+
+  async healthCheck(): Promise<boolean> {
+    return true;
+  }
+}

src/libs/db/prisma-service.ts

@@ -0,0 +1,15 @@
+import { INestApplication, Injectable, OnModuleInit } from '@nestjs/common';
+import { PrismaClient } from '@prisma/client';
+
+@Injectable()
+export class PrismaService extends PrismaClient implements OnModuleInit {
+  async onModuleInit() {
+    await this.$connect();
+  }
+
+  async enableShutdownHooks(app: INestApplication) {
+    this.$on('beforeExit', async () => {
+      await app.close();
+    });
+  }
+}

src/libs/ddd/aggregate-root.base.ts

@@ -0,0 +1,35 @@
+import { Entity } from './entity.base';
+import { EventEmitter2 } from '@nestjs/event-emitter';
+import { LoggerPort } from '@libs/ports/logger.port';
+import { DomainEvent } from './domain-event.base';
+
+export abstract class AggregateRoot<EntityProps> extends Entity<EntityProps> {
+  private _domainEvents: DomainEvent[] = [];
+
+  get domainEvents(): DomainEvent[] {
+    return this._domainEvents;
+  }
+
+  protected addEvent(domainEvent: DomainEvent): void {
+    this._domainEvents.push(domainEvent);
+  }
+
+  public clearEvents(): void {
+    this._domainEvents = [];
+  }
+
+  public async publishEvents(
+    logger: LoggerPort,
+    eventEmitter: EventEmitter2,
+  ): Promise<void> {
+    await Promise.all(
+      this.domainEvents.map(async (event) => {
+        logger.debug(
+          `"${event.constructor.name}" event published for aggregate ${this.constructor.name} : ${this.id}`,
+        );
+        return eventEmitter.emitAsync(event.constructor.name, event);
+      }),
+    );
+    this.clearEvents();
+  }
+}

src/libs/ddd/command.base.ts

@@ -0,0 +1,52 @@
+import { v4 } from 'uuid';
+import { ArgumentNotProvidedException } from '../exceptions';
+import { Guard } from '../guard';
+
+export type CommandProps<T> = Omit<T, 'id' | 'metadata'> & Partial<Command>;
+
+type CommandMetadata = {
+  /** ID for correlation purposes (for commands that
+   *  arrive from other microservices,logs correlation, etc). */
+  readonly correlationId: string;
+
+  /**
+   * Causation id to reconstruct execution order if needed
+   */
+  readonly causationId?: string;
+
+  /**
+   * ID of a user who invoker the command. Can be useful for
+   * logging and tracking execution of commands and events
+   */
+  readonly userId?: string;
+
+  /**
+   * Time when the command occurred. Mostly for tracing purposes
+   */
+  readonly timestamp: number;
+};
+
+export class Command {
+  /**
+   * Command id, in case if we want to save it
+   * for auditing purposes and create a correlation/causation chain
+   */
+  readonly id: string;
+
+  readonly metadata: CommandMetadata;
+
+  constructor(props: CommandProps<unknown>) {
+    if (Guard.isEmpty(props)) {
+      throw new ArgumentNotProvidedException(
+        'Command props should not be empty',
+      );
+    }
+    this.id = props.id || v4();
+    this.metadata = {
+      correlationId: props?.metadata?.correlationId,
+      causationId: props?.metadata?.causationId,
+      timestamp: props?.metadata?.timestamp || Date.now(),
+      userId: props?.metadata?.userId,
+    };
+  }
+}

src/libs/ddd/domain-event.base.ts

@@ -0,0 +1,52 @@
+import { ArgumentNotProvidedException } from '../exceptions';
+import { Guard } from '../guard';
+import { v4 } from 'uuid';
+
+type DomainEventMetadata = {
+  /** Timestamp when this domain event occurred */
+  readonly timestamp: number;
+
+  /** ID for correlation purposes (for Integration Events,logs correlation, etc).
+   */
+  readonly correlationId: string;
+
+  /**
+   * Causation id used to reconstruct execution order if needed
+   */
+  readonly causationId?: string;
+
+  /**
+   * User ID for debugging and logging purposes
+   */
+  readonly userId?: string;
+};
+
+export type DomainEventProps<T> = Omit<T, 'id' | 'metadata'> & {
+  aggregateId: string;
+  metadata?: DomainEventMetadata;
+};
+
+export abstract class DomainEvent {
+  public readonly id: string;
+
+  /** Aggregate ID where domain event occurred */
+  public readonly aggregateId: string;
+
+  public readonly metadata: DomainEventMetadata;
+
+  constructor(props: DomainEventProps<unknown>) {
+    if (Guard.isEmpty(props)) {
+      throw new ArgumentNotProvidedException(
+        'DomainEvent props should not be empty',
+      );
+    }
+    this.id = v4();
+    this.aggregateId = props.aggregateId;
+    this.metadata = {
+      correlationId: props?.metadata?.correlationId,
+      causationId: props?.metadata?.causationId,
+      timestamp: props?.metadata?.timestamp || Date.now(),
+      userId: props?.metadata?.userId,
+    };
+  }
+}

src/libs/ddd/entity.base.ts

@@ -0,0 +1,150 @@
+import {
+  ArgumentNotProvidedException,
+  ArgumentInvalidException,
+  ArgumentOutOfRangeException,
+} from '../exceptions';
+import { Guard } from '../guard';
+import { convertPropsToObject } from '../utils';
+
+export type AggregateID = string;
+
+export interface BaseEntityProps {
+  id: AggregateID;
+  createdAt: Date;
+  updatedAt: Date;
+}
+
+export interface CreateEntityProps<T> {
+  id: AggregateID;
+  props: T;
+  createdAt?: Date;
+  updatedAt?: Date;
+}
+
+export abstract class Entity<EntityProps> {
+  constructor({
+    id,
+    createdAt,
+    updatedAt,
+    props,
+  }: CreateEntityProps<EntityProps>) {
+    this.setId(id);
+    this.validateProps(props);
+    const now = new Date();
+    this._createdAt = createdAt || now;
+    this._updatedAt = updatedAt || now;
+    this.props = props;
+    this.validate();
+  }
+
+  protected readonly props: EntityProps;
+
+  /**
+   * ID is set in the concrete entity implementation to support
+   * different ID types depending on your needs.
+   * For example it could be a UUID for aggregate root,
+   * and shortid / nanoid for child entities.
+   */
+  protected abstract _id: AggregateID;
+
+  private readonly _createdAt: Date;
+
+  private _updatedAt: Date;
+
+  get id(): AggregateID {
+    return this._id;
+  }
+
+  private setId(id: AggregateID): void {
+    this._id = id;
+  }
+
+  get createdAt(): Date {
+    return this._createdAt;
+  }
+
+  get updatedAt(): Date {
+    return this._updatedAt;
+  }
+
+  static isEntity(entity: unknown): entity is Entity<unknown> {
+    return entity instanceof Entity;
+  }
+
+  /**
+   *  Checks if two entities are the same Entity by comparing ID field.
+   * @param object Entity
+   */
+  public equals(object?: Entity<EntityProps>): boolean {
+    if (object === null || object === undefined) {
+      return false;
+    }
+
+    if (this === object) {
+      return true;
+    }
+
+    if (!Entity.isEntity(object)) {
+      return false;
+    }
+
+    return this.id ? this.id === object.id : false;
+  }
+
+  /**
+   * Returns entity properties.
+   * @return {*}  {Props & EntityProps}
+   * @memberof Entity
+   */
+  public getProps(): EntityProps & BaseEntityProps {
+    const propsCopy = {
+      id: this._id,
+      createdAt: this._createdAt,
+      updatedAt: this._updatedAt,
+      ...this.props,
+    };
+    return Object.freeze(propsCopy);
+  }
+
+  /**
+   * Convert an Entity and all sub-entities/Value Objects it
+   * contains to a plain object with primitive types. Can be
+   * useful when logging an entity during testing/debugging
+   */
+  public toObject(): unknown {
+    const plainProps = convertPropsToObject(this.props);
+
+    const result = {
+      id: this._id,
+      createdAt: this._createdAt,
+      updatedAt: this._updatedAt,
+      ...plainProps,
+    };
+    return Object.freeze(result);
+  }
+
+  /**
+   * There are certain rules that always have to be true (invariants)
+   * for each entity. Validate method is called every time before
+   * saving an entity to the database to make sure those rules are respected.
+   */
+  public abstract validate(): void;
+
+  private validateProps(props: EntityProps): void {
+    const MAX_PROPS = 50;
+
+    if (Guard.isEmpty(props)) {
+      throw new ArgumentNotProvidedException(
+        'Entity props should not be empty',
+      );
+    }
+    if (typeof props !== 'object') {
+      throw new ArgumentInvalidException('Entity props should be an object');
+    }
+    if (Object.keys(props as any).length > MAX_PROPS) {
+      throw new ArgumentOutOfRangeException(
+        `Entity props should not have more than ${MAX_PROPS} properties`,
+      );
+    }
+  }
+}

src/libs/ddd/index.ts

@@ -0,0 +1,7 @@
+export * from './aggregate-root.base';
+export * from './command.base';
+export * from './domain-event.base';
+export * from './entity.base';
+export * from './mapper.interface';
+export * from './repository.port';
+export * from './value-object.base';

src/libs/ddd/mapper.interface.ts

@@ -0,0 +1,11 @@
+import { Entity } from './entity.base';
+
+export interface Mapper<
+  DomainEntity extends Entity<any>,
+  DbRecord,
+  Response = any,
+> {
+  toPersistence(entity: DomainEntity): DbRecord;
+  toDomain(record: any): DomainEntity;
+  toResponse(entity: DomainEntity): Response;
+}

src/libs/ddd/repository.port.ts

@@ -0,0 +1,42 @@
+import { Option } from 'oxide.ts';
+
+/*  Most of repositories will probably need generic
+    save/find/delete operations, so it's easier
+    to have some shared interfaces.
+    More specific queries should be defined
+    in a respective repository.
+*/
+
+export class Paginated<T> {
+  readonly count: number;
+  readonly limit: number;
+  readonly page: number;
+  readonly data: readonly T[];
+
+  constructor(props: Paginated<T>) {
+    this.count = props.count;
+    this.limit = props.limit;
+    this.page = props.page;
+    this.data = props.data;
+  }
+}
+
+export type OrderBy = { field: string | true; param: 'asc' | 'desc' };
+
+export type PaginatedQueryParams = {
+  limit: number;
+  page: number;
+  offset: number;
+  orderBy: OrderBy;
+};
+
+export interface RepositoryPort<Entity> {
+  insert(entity: Entity | Entity[]): Promise<void>;
+  findOneById(id: string): Promise<Option<Entity>>;
+  healthCheck(): Promise<boolean>;
+  // findAll(): Promise<Entity[]>;
+  // findAllPaginated(params: PaginatedQueryParams): Promise<Paginated<Entity>>;
+  // delete(entity: Entity): Promise<boolean>;
+
+  // transaction<T>(handler: () => Promise<T>): Promise<T>;
+}

src/libs/ddd/value-object.base.ts

@@ -0,0 +1,71 @@
+import { ArgumentNotProvidedException } from '../exceptions';
+import { Guard } from '../guard';
+import { convertPropsToObject } from '../utils';
+
+/**
+ * Domain Primitive is an object that contains only a single value
+ */
+export type Primitives = string | number | boolean;
+export interface DomainPrimitive<T extends Primitives | Date> {
+  value: T;
+}
+
+type ValueObjectProps<T> = T extends Primitives | Date ? DomainPrimitive<T> : T;
+
+export abstract class ValueObject<T> {
+  protected readonly props: ValueObjectProps<T>;
+
+  constructor(props: ValueObjectProps<T>) {
+    this.checkIfEmpty(props);
+    this.validate(props);
+    this.props = props;
+  }
+
+  protected abstract validate(props: ValueObjectProps<T>): void;
+
+  static isValueObject(obj: unknown): obj is ValueObject<unknown> {
+    return obj instanceof ValueObject;
+  }
+
+  /**
+   *  Check if two Value Objects are equal. Checks structural equality.
+   * @param vo ValueObject
+   */
+  public equals(vo?: ValueObject<T>): boolean {
+    if (vo === null || vo === undefined) {
+      return false;
+    }
+    return JSON.stringify(this) === JSON.stringify(vo);
+  }
+
+  /**
+   * Unpack a value object to get its raw properties
+   */
+  public unpack(): T {
+    if (this.isDomainPrimitive(this.props)) {
+      return this.props.value;
+    }
+
+    const propsCopy = convertPropsToObject(this.props);
+
+    return Object.freeze(propsCopy);
+  }
+
+  private checkIfEmpty(props: ValueObjectProps<T>): void {
+    if (
+      Guard.isEmpty(props) ||
+      (this.isDomainPrimitive(props) && Guard.isEmpty(props.value))
+    ) {
+      throw new ArgumentNotProvidedException('Property cannot be empty');
+    }
+  }
+
+  private isDomainPrimitive(
+    obj: unknown,
+  ): obj is DomainPrimitive<T & (Primitives | Date)> {
+    if (Object.prototype.hasOwnProperty.call(obj, 'value')) {
+      return true;
+    }
+    return false;
+  }
+}

src/libs/exceptions/exception.base.ts

@@ -0,0 +1,63 @@
+export interface SerializedException {
+  message: string;
+  code: string;
+  correlationId: string;
+  stack?: string;
+  cause?: string;
+  metadata?: unknown;
+  /**
+   * ^ Consider adding optional `metadata` object to
+   * exceptions (if language doesn't support anything
+   * similar by default) and pass some useful technical
+   * information about the exception when throwing.
+   * This will make debugging easier.
+   */
+}
+
+/**
+ * Base class for custom exceptions.
+ *
+ * @abstract
+ * @class ExceptionBase
+ * @extends {Error}
+ */
+export abstract class ExceptionBase extends Error {
+  abstract code: string;
+
+  public readonly correlationId: string;
+
+  /**
+   * @param {string} message
+   * @param {ObjectLiteral} [metadata={}]
+   * **BE CAREFUL** not to include sensitive info in 'metadata'
+   * to prevent leaks since all exception's data will end up
+   * in application's log files. Only include non-sensitive
+   * info that may help with debugging.
+   */
+  constructor(
+    readonly message: string,
+    readonly cause?: Error,
+    readonly metadata?: unknown,
+  ) {
+    super(message);
+    Error.captureStackTrace(this, this.constructor);
+  }
+
+  /**
+   * By default in NodeJS Error objects are not
+   * serialized properly when sending plain objects
+   * to external processes. This method is a workaround.
+   * Keep in mind not to return a stack trace to user when in production.
+   * https://iaincollins.medium.com/error-handling-in-javascript-a6172ccdf9af
+   */
+  toJSON(): SerializedException {
+    return {
+      message: this.message,
+      code: this.code,
+      stack: this.stack,
+      correlationId: this.correlationId,
+      cause: JSON.stringify(this.cause),
+      metadata: this.metadata,
+    };
+  }
+}

src/libs/exceptions/exception.codes.ts

@@ -0,0 +1,15 @@
+/**
+ * Adding a `code` string with a custom status code for every
+ * exception is a good practice, since when that exception
+ * is transferred to another process `instanceof` check
+ * cannot be performed anymore so a `code` string is used instead.
+ * code constants can be stored in a separate file so they
+ * can be shared and reused on a receiving side (code sharing is
+ * useful when developing fullstack apps or microservices)
+ */
+export const ARGUMENT_INVALID = 'GENERIC.ARGUMENT_INVALID';
+export const ARGUMENT_OUT_OF_RANGE = 'GENERIC.ARGUMENT_OUT_OF_RANGE';
+export const ARGUMENT_NOT_PROVIDED = 'GENERIC.ARGUMENT_NOT_PROVIDED';
+export const NOT_FOUND = 'GENERIC.NOT_FOUND';
+export const CONFLICT = 'GENERIC.CONFLICT';
+export const INTERNAL_SERVER_ERROR = 'GENERIC.INTERNAL_SERVER_ERROR';

src/libs/exceptions/exceptions.ts

@@ -0,0 +1,82 @@
+import {
+  ARGUMENT_INVALID,
+  ARGUMENT_NOT_PROVIDED,
+  ARGUMENT_OUT_OF_RANGE,
+  CONFLICT,
+  INTERNAL_SERVER_ERROR,
+  NOT_FOUND,
+} from '.';
+import { ExceptionBase } from './exception.base';
+
+/**
+ * Used to indicate that an incorrect argument was provided to a method/function/class constructor
+ *
+ * @class ArgumentInvalidException
+ * @extends {ExceptionBase}
+ */
+export class ArgumentInvalidException extends ExceptionBase {
+  readonly code = ARGUMENT_INVALID;
+}
+
+/**
+ * Used to indicate that an argument was not provided (is empty object/array, null of undefined).
+ *
+ * @class ArgumentNotProvidedException
+ * @extends {ExceptionBase}
+ */
+export class ArgumentNotProvidedException extends ExceptionBase {
+  readonly code = ARGUMENT_NOT_PROVIDED;
+}
+
+/**
+ * Used to indicate that an argument is out of allowed range
+ * (for example: incorrect string/array length, number not in allowed min/max range etc)
+ *
+ * @class ArgumentOutOfRangeException
+ * @extends {ExceptionBase}
+ */
+export class ArgumentOutOfRangeException extends ExceptionBase {
+  readonly code = ARGUMENT_OUT_OF_RANGE;
+}
+
+/**
+ * Used to indicate conflicting entities (usually in the database)
+ *
+ * @class ConflictException
+ * @extends {ExceptionBase}
+ */
+export class ConflictException extends ExceptionBase {
+  readonly code = CONFLICT;
+}
+
+/**
+ * Used to indicate that entity is not found
+ *
+ * @class NotFoundException
+ * @extends {ExceptionBase}
+ */
+export class NotFoundException extends ExceptionBase {
+  static readonly message = 'Not found';
+
+  constructor(message = NotFoundException.message) {
+    super(message);
+  }
+
+  readonly code = NOT_FOUND;
+}
+
+/**
+ * Used to indicate an internal server error that does not fall under all other errors
+ *
+ * @class InternalServerErrorException
+ * @extends {ExceptionBase}
+ */
+export class InternalServerErrorException extends ExceptionBase {
+  static readonly message = 'Internal server error';
+
+  constructor(message = InternalServerErrorException.message) {
+    super(message);
+  }
+
+  readonly code = INTERNAL_SERVER_ERROR;
+}

src/libs/exceptions/index.ts

@@ -0,0 +1,3 @@
+export * from './exception.base';
+export * from './exception.codes';
+export * from './exceptions';

src/libs/guard.ts

@@ -0,0 +1,55 @@
+export class Guard {
+  /**
+   * Checks if value is empty. Accepts strings, numbers, booleans, objects and arrays.
+   */
+  static isEmpty(value: unknown): boolean {
+    if (typeof value === 'number' || typeof value === 'boolean') {
+      return false;
+    }
+    if (typeof value === 'undefined' || value === null) {
+      return true;
+    }
+    if (value instanceof Date) {
+      return false;
+    }
+    if (value instanceof Object && !Object.keys(value).length) {
+      return true;
+    }
+    if (Array.isArray(value)) {
+      if (value.length === 0) {
+        return true;
+      }
+      if (value.every((item) => Guard.isEmpty(item))) {
+        return true;
+      }
+    }
+    if (value === '') {
+      return true;
+    }
+
+    return false;
+  }
+
+  /**
+   * Checks length range of a provided number/string/array
+   */
+  static lengthIsBetween(
+    value: number | string | Array<unknown>,
+    min: number,
+    max: number,
+  ): boolean {
+    if (Guard.isEmpty(value)) {
+      throw new Error(
+        'Cannot check length of a value. Provided value is empty',
+      );
+    }
+    const valueLength =
+      typeof value === 'number'
+        ? Number(value).toString().length
+        : value.length;
+    if (valueLength >= min && valueLength <= max) {
+      return true;
+    }
+    return false;
+  }
+}

src/libs/ports/logger.port.ts

@@ -0,0 +1,6 @@
+export interface LoggerPort {
+  log(message: string, ...meta: unknown[]): void;
+  error(message: string, trace?: unknown, ...meta: unknown[]): void;
+  warn(message: string, ...meta: unknown[]): void;
+  debug(message: string, ...meta: unknown[]): void;
+}

src/libs/ports/prisma-repository.port.ts

@@ -0,0 +1,4 @@
+export interface PrismaRepositoryPort<Entity> {
+  findUnique(options: any): Promise<Entity>;
+  create(entity: any): Promise<Entity>;
+}

src/libs/types/index.ts

@@ -0,0 +1,6 @@
+/** Consider creating a bunch of shared custom utility
+ * types for different situations.
+ * Alternatively you can use a library like
+ * https://github.com/andnp/SimplyTyped
+ */
+export * from './object-literal.type';

src/libs/types/object-literal.type.ts

@@ -0,0 +1,6 @@
+/**
+ * Interface of the simple literal object with any string keys.
+ */
+export interface ObjectLiteral {
+  [key: string]: unknown;
+}

src/libs/utils/convert-props-to-object.util.ts

@@ -0,0 +1,47 @@
+/* eslint-disable @typescript-eslint/no-explicit-any, @typescript-eslint/explicit-module-boundary-types */
+import { Entity } from '../ddd/entity.base';
+import { ValueObject } from '../ddd/value-object.base';
+
+function isEntity(obj: unknown): obj is Entity<unknown> {
+  /**
+   * 'instanceof Entity' causes error here for some reason.
+   * Probably creates some circular dependency. This is a workaround
+   * until I find a solution :)
+   */
+  return (
+    Object.prototype.hasOwnProperty.call(obj, 'toObject') &&
+    Object.prototype.hasOwnProperty.call(obj, 'id') &&
+    ValueObject.isValueObject((obj as Entity<unknown>).id)
+  );
+}
+
+function convertToPlainObject(item: any): any {
+  if (ValueObject.isValueObject(item)) {
+    return item.unpack();
+  }
+  if (isEntity(item)) {
+    return item.toObject();
+  }
+  return item;
+}
+
+/**
+ * Converts Entity/Value Objects props to a plain object.
+ * Useful for testing and debugging.
+ * @param props
+ */
+export function convertPropsToObject(props: any): any {
+  const propsCopy = structuredClone(props);
+
+  // eslint-disable-next-line guard-for-in
+  for (const prop in propsCopy) {
+    if (Array.isArray(propsCopy[prop])) {
+      propsCopy[prop] = (propsCopy[prop] as Array<unknown>).map((item) => {
+        return convertToPlainObject(item);
+      });
+    }
+    propsCopy[prop] = convertToPlainObject(propsCopy[prop]);
+  }
+
+  return propsCopy;
+}

src/libs/utils/index.ts

@@ -0,0 +1 @@
+export * from './convert-props-to-object.util';