feat: add QuestionDetails value object

Author: joschonarth

src/domain/forum/application/repositories/questions-repository.ts

@@ -1,9 +1,11 @@
 import { PaginationParams } from '@/core/repositories/pagination-params'
 import { Question } from '../../enterprise/entities/question'
+import { QuestionDetails } from '../../enterprise/entities/value-objects/question-details'
 
 export abstract class QuestionsRepository {
   abstract findById(id: string): Promise<Question | null>
   abstract findBySlug(slug: string): Promise<Question | null>
+  abstract findDetailsBySlug(slug: string): Promise<QuestionDetails | null>
   abstract findManyRecent(params: PaginationParams): Promise<Question[]>
   abstract save(question: Question): Promise<void>
   abstract create(question: Question): Promise<void>

src/domain/forum/application/use-cases/get-question-by-slug.ts

@@ -1,8 +1,8 @@
 import { Either, left, right } from '@/core/either'
-import { Question } from '../../enterprise/entities/question'
 import { QuestionsRepository } from '../repositories/questions-repository'
 import { ResourceNotFoundError } from '@/core/errors/resource-not-found-error'
 import { Injectable } from '@nestjs/common'
+import { QuestionDetails } from '../../enterprise/entities/value-objects/question-details'
 
 interface GetQuestionBySlugUseCaseRequest {
   slug: string
@@ -11,7 +11,7 @@ interface GetQuestionBySlugUseCaseRequest {
 type GetQuestionBySlugUseCaseResponse = Either<
   ResourceNotFoundError,
   {
-    question: Question
+    question: QuestionDetails
   }
 >
 
@@ -22,7 +22,7 @@ export class GetQuestionBySlugUseCase {
   async execute({
     slug,
   }: GetQuestionBySlugUseCaseRequest): Promise<GetQuestionBySlugUseCaseResponse> {
-    const question = await this.questionsRepository.findBySlug(slug)
+    const question = await this.questionsRepository.findDetailsBySlug(slug)
 
     if (!question) {
       return left(new ResourceNotFoundError())

src/domain/forum/enterprise/entities/value-objects/question-details.ts

@@ -0,0 +1,63 @@
+import { UniqueEntityID } from '@/core/entities/unique-entity-id'
+import { ValueObject } from '@/core/entities/value-object'
+import { Slug } from './slug'
+import { Attachment } from '../attachment'
+
+export interface QuestionDetailsProps {
+  questionId: UniqueEntityID
+  authorId: UniqueEntityID
+  author: string
+  title: string
+  content: string
+  slug: Slug
+  attachments: Attachment[]
+  bestAnswerId?: UniqueEntityID | null
+  createdAt: Date
+  updatedAt?: Date | null
+}
+
+export class QuestionDetails extends ValueObject<QuestionDetailsProps> {
+  get questionId() {
+    return this.props.questionId
+  }
+
+  get authorId() {
+    return this.props.authorId
+  }
+
+  get author() {
+    return this.props.author
+  }
+
+  get title() {
+    return this.props.title
+  }
+
+  get content() {
+    return this.props.content
+  }
+
+  get slug() {
+    return this.props.slug
+  }
+
+  get attachments() {
+    return this.props.attachments
+  }
+
+  get bestAnswerId() {
+    return this.props.bestAnswerId
+  }
+
+  get createdAt() {
+    return this.props.createdAt
+  }
+
+  get updatedAt() {
+    return this.props.updatedAt
+  }
+
+  static create(props: QuestionDetailsProps) {
+    return new QuestionDetails(props)
+  }
+}

test/repositories/in-memory-questions-repository.ts

@@ -1,14 +1,19 @@
 import { DomainEvents } from '@/core/events/domain-events'
 import { PaginationParams } from '@/core/repositories/pagination-params'
-import { QuestionAttachmentsRepository } from '@/domain/forum/application/repositories/question-attachments-repository'
 import { QuestionsRepository } from '@/domain/forum/application/repositories/questions-repository'
 import { Question } from '@/domain/forum/enterprise/entities/question'
+import { InMemoryStudentsRepository } from './in-memory-students-repository'
+import { InMemoryAttachmentsRepository } from './in-memory-attachments-repository'
+import { InMemoryQuestionAttachmentsRepository } from './in-memory-question-attachments-repository'
+import { QuestionDetails } from '@/domain/forum/enterprise/entities/value-objects/question-details'
 
 export class InMemoryQuestionsRepository implements QuestionsRepository {
   public items: Question[] = []
 
   constructor(
-    private questionAttachmentsRepository: QuestionAttachmentsRepository,
+    private questionAttachmentsRepository: InMemoryQuestionAttachmentsRepository,
+    private attachmentsRepository: InMemoryAttachmentsRepository,
+    private studentsRepository: InMemoryStudentsRepository,
   ) {}
 
   async findById(id: string) {
@@ -31,6 +36,57 @@ export class InMemoryQuestionsRepository implements QuestionsRepository {
     return question
   }
 
+  async findDetailsBySlug(slug: string) {
+    const question = this.items.find((item) => item.slug.value === slug)
+
+    if (!question) {
+      return null
+    }
+
+    const author = this.studentsRepository.items.find((student) => {
+      return student.id.equals(question.authorId)
+    })
+
+    if (!author) {
+      throw new Error(
+        `Author with ID "${question.authorId.toString()}" does not exist.`,
+      )
+    }
+
+    const questionAttachments = this.questionAttachmentsRepository.items.filter(
+      (questionAttachment) => {
+        return questionAttachment.questionId.equals(question.id)
+      },
+    )
+
+    const attachments = questionAttachments.map((questionAttachment) => {
+      const attachment = this.attachmentsRepository.items.find((attachment) => {
+        return attachment.id.equals(questionAttachment.attachmentId)
+      })
+
+      if (!attachment) {
+        throw new Error(
+          `Attachment with ID "${questionAttachment.attachmentId.toString()}" does not exist.`,
+        )
+      }
+
+      return attachment
+    })
+
+    return QuestionDetails.create({
+      questionId: question.id,
+      authorId: question.authorId,
+      author: author.name,
+      title: question.title,
+      slug: question.slug,
+      content: question.content,
+      bestAnswerId: question.bestAnswerId,
+      attachments,
+      createdAt: question.createdAt,
+      updatedAt: question.updatedAt,
+    })
+  }
+
   async findManyRecent({ page }: PaginationParams) {
     const questions = this.items
       .sort((a, b) => b.createdAt.getTime() - a.createdAt.getTime())