Shortest path algorithm, tests and Postman

- Added algorithm and endpoint to find the shortest path between two
  topics;
- Added respective test;
- Added a JSON collection with API calls that can be imported into
  Postman for the convenience of the user.

src/controllers/topicController.ts

@@ -1,110 +1,127 @@
-import { Request, Response, NextFunction } from 'express';
-import { topics, Topic, TopicNode } from '../models/topic';
-import { finder } from '../utils'
+import { Request, Response, NextFunction } from 'express'
+import { topics, Topic, TopicNode } from '../models/topic'
+import { finder, shortestPath } from '../utils'
 
 // Create a topic
 export const createTopic = (req: Request, res: Response, next: NextFunction) => {
   try {
-    const { name, content, parentTopicId } = req.body;
+    const { name, content, parentTopicId } = req.body
     const newTopic = new TopicNode(name, content, null, null, null, parentTopicId)
-    topics.push(newTopic);
+    topics.push(newTopic)
 
-    res.status(201).json(newTopic);
+    res.status(201).json(newTopic)
   } catch (error) {
-    next(error);
+    next(error)
   }
-};
+}
 
 // Retrieve all topics
 export const getTopics = (req: Request, res: Response, next: NextFunction) => {
   try {
-    res.json(topics);
+    res.json(topics)
   } catch (error) {
-    next(error);
+    next(error)
   }
-};
+}
 
 // Retrieve single topic
 export const getTopicById = (req: Request, res: Response, next: NextFunction) => {
   try {
-    const id = parseInt(req.params.id, 10);
-    const topic = topics.find((i) => i.id === id);
+    const id = parseInt(req.params.id, 10)
+    const topic = topics.find((i) => i.id === id)
     if (!topic) {
-      res.status(404).json({ message: 'Topic not found' });
-      return;
+      res.status(404).json({ message: 'Topic not found' })
+      return
     }
-    res.json(topic);
+    res.status(302).json(topic)
   } catch (error) {
-    next(error);
+    next(error)
   }
-};
+}
 
 // Retrieve single version of a topic
 export const getTopicByIdVersion = (req: Request, res: Response, next: NextFunction) => {
   try {
-    const id = parseInt(req.params.id, 10);
+    const id = parseInt(req.params.id, 10)
     const version = parseInt(req.params.version, 10)
-    const topic = topics.find((i) => i.id === id && i.version === version);
+    const topic = topics.find((i) => i.id === id && i.version === version)
     if (!topic) {
-      res.status(404).json({ message: 'Topic not found' });
-      return;
+      res.status(404).json({ message: 'Topic not found' })
+      return
     }
-    res.json(topic);
+    res.status(302).json(topic)
   } catch (error) {
-    next(error);
+    next(error)
   }
-};
+}
 
-// Retrive topic and all subtopics recursively
+// Retrieve topic and all subtopics recursively
 export const getTopicByIdRecursive = (req: Request, res: Response, next: NextFunction) => {
   try {
-    const id = parseInt(req.params.id, 10);
-    const topic = topics.find((i) => i.id === id);
+    const id = parseInt(req.params.id, 10)
+    const topic = topics.find((i) => i.id === id)
     if (!topic) {
-      res.status(404).json({ message: 'Topic not found' });
-      return;
+      res.status(404).json({ message: 'Topic not found' })
+      return
     }
     const result = finder(topic.id)
 
-    res.json(result);
+    res.status(302).json(result)
   } catch (error) {
-    next(error);
+    next(error)
   }
-};
+}
 
 // Update a topic (create nenw version)
 export const updateTopic = (req: Request, res: Response, next: NextFunction) => {
   try {
-    const id = parseInt(req.params.id, 10);
-    const { name, content, parentTopicId } = req.body;
+    const id = parseInt(req.params.id, 10)
+    const { name, content, parentTopicId } = req.body
     const oldTopicArray = topics.filter(t => t.id === id)
 
     if (oldTopicArray.length === 0) {
-      res.status(404).json({ message: 'Topic not found' });
-      return;
+      res.status(404).json({ message: 'Topic not found' })
+      return
     }
 
     const oldTopic = oldTopicArray[oldTopicArray.length - 1]
     const newTopic = oldTopic.update(name, content, parentTopicId)
 
-    res.status(201).json(newTopic)
+    res.status(202).json(newTopic)
   } catch (error) {
-    next(error);
+    next(error)
   }
-};
+}
 
 // Delete a topic
 export const deleteTopic = (req: Request, res: Response, next: NextFunction) => {
   try {
-    const id = parseInt(req.params.id, 10);
-    const topicIndex = topics.findIndex((i) => i.id === id);
+    const id = parseInt(req.params.id, 10)
+    const topicIndex = topics.findIndex((i) => i.id === id)
     if (topicIndex === -1) {
-      res.status(404).json({ message: 'Topic not found' });
-      return;
+      res.status(404).json({ message: 'Topic not found' })
+      return
     }
-    const deletedTopic = topics.splice(topicIndex, 1)[0];
-    res.json(deletedTopic);
+    const deletedTopic = topics.splice(topicIndex, 1)[0]
+    res.status(202).json(deletedTopic)
   } catch (error) {
-    next(error);
+    next(error)
   }
-};
+}
+
+// Find shortest path between topics
+export const getShortestPath = (req: Request, res: Response, next: NextFunction) => {
+  try {
+    const idA = parseInt(req.params.idA, 10)
+    const idB = parseInt(req.params.idB, 10)
+    const result = shortestPath(idA, idB)
+
+    if (result.length === 0 || result.name) {
+      res.status(404).json('path does not exist')
+    } else {
+      res.status(302).json(result)
+    }
+  } catch (error) {
+    next(error)
+  }
+}