implements a category route

services/CategoryService.js

@@ -0,0 +1,29 @@
+const createError = require('http-errors');
+const CategoryModel = require('../models/CategoryModel');
+const CategoryInstance = new CategoryModel();
+
+module.exports = class CategoryService {
+    async getAll() {
+        const result = await CategoryInstance.getAll();
+        if (!result) throw createError(404, "Resource not found.");
+        return result;
+    }
+
+    async getById(id) {
+        const result = await CategoryInstance.getById(id);
+        if (!result) throw createError(404, "Resource not found.");
+        return result;
+    }
+    
+    async getByName(name) {
+        const result = await CategoryInstance.getByName(name);
+        if (!result) throw createError(404, "Resource not found.");
+        return result;
+    }
+
+    async create(data) {
+        const result = await CategoryInstance.insertOne(data);
+        if (!result) throw createError(404, "Resource not found.");
+        return result;
+    }
+}