setup the express server, and added API endpoints

.gitignore

@@ -1,3 +1,4 @@
 node_modules/
 build/
 .env
+.env.development

backend/index.js

@@ -0,0 +1,70 @@
+const express = require('express');
+const cors = require('cors');
+const app = express();
+
+app.use(cors());
+app.use(express.json());
+
+let tasks = [{ id: 1, title: 'Laundry', description: 'wash, dry and fold clothes', status: "not yet completed" }];
+
+const getNewId = () => {
+    const ids = tasks.map(task => task.id);
+    let newId = tasks.length + 1;
+    while(true) {
+        if (!ids.includes(newId)) return newId;
+        newId++;
+    }
+}
+
+app.get('/tasks', (req, res) => {
+    res.status(200).json(tasks);
+});
+app.post('/tasks', (req, res) => {
+    // expect title, description, status in the request body
+    const newTask = req.body;
+    if (newTask.title && newTask.description && newTask.status) {
+        newTask.id = getNewId();
+        tasks.push(newTask);
+        res.status(201).json(newTask)
+    } else {
+        res.status(400).send('Unable to create task. Invalid or incorrect data');
+    }
+});
+app.get('/tasks/:id', (req, res) => {
+    const { id } = req.params;
+    const numId = Number(id);
+    const index = tasks.findIndex(task => task.id === numId);
+    if (index !== -1) {
+        res.status(200).json(tasks[index]);
+    } else {
+        res.status(404).send('Task not found');
+    }
+})
+app.put('/tasks/:id', (req, res) => {
+    // can update title, description or status
+    const { id } = req.params;
+    const numId = Number(id);
+    const index = tasks.findIndex(task => task.id === numId);
+    if (index !== -1) {
+        tasks[index] = { ...tasks[index], ...req.body };
+        res.status(200).json(tasks[index]);
+    } else {
+        res.status(404).send('Task not found');
+    }
+})
+app.delete('/tasks/:id', (req, res) => {
+    const { id } = req.params;
+    const numId = Number(id);
+    const index = tasks.findIndex(task => task.id === numId);
+    if (index !== -1) {
+        tasks.splice(index, 1);
+        console.log("task deleted");
+        res.status(200).json('Task successfully deleted');
+    } else {
+        res.status(404).send('Task not found');
+    }
+})
+
+module.exports = {
+    app: app
+};