Classes and interfaces

Changed the topic model to use classes and interfaces instead of direct
assignments.

src/controllers/topicController.ts

@@ -1,22 +1,12 @@
 import { Request, Response, NextFunction } from 'express';
-import { topics, Topic } from '../models/topic';
+import { topics, Topic, TopicNode } from '../models/topic';
 import { finder } from '../utils'
 
 // Create a topic
 export const createTopic = (req: Request, res: Response, next: NextFunction) => {
   try {
-    const { name, content } = req.body;
+    const { name, content, parentTopicId } = req.body;
-
+    const newTopic = new TopicNode(name, content, null, null, null, parentTopicId)
-    const newTopic: Topic = {
-      id: Date.now(),
-      name,
-      content,
-      createdAt: new Date().toString(),
-      updatedAt: new Date().toString(),
-      version: 1,
-      parentTopicId: req.body.parentTopicId ?? undefined
-    };
-
     topics.push(newTopic);
 
     res.status(201).json(newTopic);
@@ -86,8 +76,7 @@ export const getTopicByIdRecursive = (req: Request, res: Response, next: NextFun
 export const updateTopic = (req: Request, res: Response, next: NextFunction) => {
   try {
     const id = parseInt(req.params.id, 10);
-    const { name } = req.body;
+    const { name, content, parentTopicId } = req.body;
-
     const oldTopicArray = topics.filter(t => t.id === id)
 
     if (oldTopicArray.length === 0) {
@@ -96,18 +85,7 @@ export const updateTopic = (req: Request, res: Response, next: NextFunction) =>
     }
 
     const oldTopic = oldTopicArray[oldTopicArray.length - 1]
-
+    const newTopic = oldTopic.update(name, content, parentTopicId)
-    const newTopic: Topic = {
-      id: oldTopic.id,
-      name: oldTopic.name,
-      content: oldTopic.content,
-      createdAt: oldTopic.createdAt,
-      updatedAt: new Date().toString(),
-      version: oldTopic.version + 1,
-      parentTopicId: oldTopic.parentTopicId ?? undefined
-    };
-
-    topics.push(newTopic)
 
     res.status(201).json(newTopic)
   } catch (error) {

src/models/topic.ts

@@ -6,6 +6,55 @@ export interface Topic {
   updatedAt: string
   version: number
   parentTopicId?: number
+
+  update(name:string, content: string, parentTopicId: number): Topic
+}
+
+export class TopicNode implements Topic {
+  id: number
+  name: string
+  content: string
+  createdAt: string
+  updatedAt: string
+  version: number
+  parentTopicId?: number
+
+  constructor(
+    name: string,
+    content: string,
+    id?: number,
+    createdAt?: string,
+    version?: number,
+    parentTopicId?: number
+  ) {
+    this.id = id ?? Date.now()
+    this.name = name
+    this.content = content
+    this.parentTopicId = parentTopicId ?? undefined
+    this.createdAt = createdAt ?? new Date().toString()
+    this.updatedAt = new Date().toString()
+    this.version = version ? version++ : 1
+  }
+
+  update(name: string, content: string, parentTopicId: number) {
+    const newName = name ?? this.name
+    const newContent = content ?? this.content
+    const newVersion = this.version + 1
+    const newParentTopicId = parentTopicId ?? this.parentTopicId
+
+    const newTopic = new TopicNode(
+      newName,
+      newContent,
+      this.id,
+      this.createdAt,
+      newVersion,
+      newParentTopicId
+    )
+
+    topics.push(newTopic)
+
+    return (newTopic)
+  }
 }
 
 export const topics: Topic[] = [];