Add tutorial for building a fitness app

ISSUE_TEMPLATE.md

@@ -37,3 +37,4 @@ Thanks for your contribution! If you're submitting a tutorial, please ensure it
 * [ ] Web Search Engine
 * [ ] Web Server
 * [ ] Uncategorized
+* [ ] Fitness App

README.md

@@ -35,6 +35,7 @@ It's a great way to learn.
 * [Web Browser](#build-your-own-web-browser)
 * [Web Server](#build-your-own-web-server)
 * [Uncategorized](#uncategorized)
+* [Fitness App](#build-your-own-fitness-app)
 
 ## Tutorials
 
@@ -408,6 +409,10 @@ It's a great way to learn.
 * [**Python**: _Implementing a RESTful Web API with Python & Flask_](http://blog.luisrei.com/articles/flaskrest.html)
 * [**Ruby**: _Building a simple websockets server from scratch in Ruby_](http://blog.honeybadger.io/building-a-simple-websockets-server-from-scratch-in-ruby/)
 
+#### Build your own `Fitness App`
+
+* [**JavaScript**: _Build a simple fitness app similar to Fitbud_](tutorials/fitness-app.md)
+
 #### Uncategorized
 
 * [**(any)**: _From NAND to Tetris: Building a Modern Computer From First Principles_](http://nand2tetris.org/)

tutorials/fitness-app.md

@@ -0,0 +1,195 @@
+# Build a Simple Fitness App
+
+In this tutorial, we will build a simple fitness app similar to Fitbud. The app will allow users to track their workouts, set goals, and monitor their progress. We will use JavaScript and a few other technologies to create this app.
+
+## Step 1: Setting Up the Project
+
+First, let's set up our project. Create a new directory for your project and initialize a new Node.js project:
+
+```bash
+mkdir fitness-app
+cd fitness-app
+npm init -y
+```
+
+Next, install the necessary dependencies:
+
+```bash
+npm install express body-parser mongoose
+```
+
+## Step 2: Creating the Server
+
+We will use Express to create our server. Create a new file called `server.js` and add the following code:
+
+```javascript
+const express = require('express');
+const bodyParser = require('body-parser');
+const mongoose = require('mongoose');
+
+const app = express();
+const port = 3000;
+
+app.use(bodyParser.json());
+
+mongoose.connect('mongodb://localhost/fitness-app', { useNewUrlParser: true, useUnifiedTopology: true });
+
+app.listen(port, () => {
+  console.log(`Server is running on port ${port}`);
+});
+```
+
+## Step 3: Creating the User Model
+
+We will use Mongoose to create our user model. Create a new file called `models/User.js` and add the following code:
+
+```javascript
+const mongoose = require('mongoose');
+
+const userSchema = new mongoose.Schema({
+  username: { type: String, required: true, unique: true },
+  password: { type: String, required: true },
+  workouts: [{ type: mongoose.Schema.Types.ObjectId, ref: 'Workout' }]
+});
+
+const User = mongoose.model('User', userSchema);
+
+module.exports = User;
+```
+
+## Step 4: Creating the Workout Model
+
+Next, create a new file called `models/Workout.js` and add the following code:
+
+```javascript
+const mongoose = require('mongoose');
+
+const workoutSchema = new mongoose.Schema({
+  user: { type: mongoose.Schema.Types.ObjectId, ref: 'User', required: true },
+  date: { type: Date, required: true },
+  exercises: [{
+    name: { type: String, required: true },
+    sets: { type: Number, required: true },
+    reps: { type: Number, required: true },
+    weight: { type: Number, required: true }
+  }]
+});
+
+const Workout = mongoose.model('Workout', workoutSchema);
+
+module.exports = Workout;
+```
+
+## Step 5: Creating the User Routes
+
+Create a new file called `routes/user.js` and add the following code:
+
+```javascript
+const express = require('express');
+const router = express.Router();
+const User = require('../models/User');
+
+router.post('/register', async (req, res) => {
+  try {
+    const user = new User(req.body);
+    await user.save();
+    res.status(201).send(user);
+  } catch (error) {
+    res.status(400).send(error);
+  }
+});
+
+router.post('/login', async (req, res) => {
+  try {
+    const user = await User.findOne({ username: req.body.username, password: req.body.password });
+    if (!user) {
+      return res.status(401).send({ error: 'Invalid credentials' });
+    }
+    res.send(user);
+  } catch (error) {
+    res.status(400).send(error);
+  }
+});
+
+module.exports = router;
+```
+
+## Step 6: Creating the Workout Routes
+
+Create a new file called `routes/workout.js` and add the following code:
+
+```javascript
+const express = require('express');
+const router = express.Router();
+const Workout = require('../models/Workout');
+
+router.post('/', async (req, res) => {
+  try {
+    const workout = new Workout(req.body);
+    await workout.save();
+    res.status(201).send(workout);
+  } catch (error) {
+    res.status(400).send(error);
+  }
+});
+
+router.get('/:userId', async (req, res) => {
+  try {
+    const workouts = await Workout.find({ user: req.params.userId });
+    res.send(workouts);
+  } catch (error) {
+    res.status(400).send(error);
+  }
+});
+
+module.exports = router;
+```
+
+## Step 7: Integrating the Routes
+
+Update the `server.js` file to include the user and workout routes:
+
+```javascript
+const express = require('express');
+const bodyParser = require('body-parser');
+const mongoose = require('mongoose');
+const userRoutes = require('./routes/user');
+const workoutRoutes = require('./routes/workout');
+
+const app = express();
+const port = 3000;
+
+app.use(bodyParser.json());
+
+mongoose.connect('mongodb://localhost/fitness-app', { useNewUrlParser: true, useUnifiedTopology: true });
+
+app.use('/users', userRoutes);
+app.use('/workouts', workoutRoutes);
+
+app.listen(port, () => {
+  console.log(`Server is running on port ${port}`);
+});
+```
+
+## Step 8: Testing the API
+
+You can use a tool like Postman to test the API. Here are some example requests:
+
+- Register a new user:
+  - POST http://localhost:3000/users/register
+  - Body: `{ "username": "testuser", "password": "password123" }`
+
+- Login a user:
+  - POST http://localhost:3000/users/login
+  - Body: `{ "username": "testuser", "password": "password123" }`
+
+- Create a new workout:
+  - POST http://localhost:3000/workouts
+  - Body: `{ "user": "userId", "date": "2021-01-01", "exercises": [{ "name": "Squat", "sets": 3, "reps": 10, "weight": 100 }] }`
+
+- Get workouts for a user:
+  - GET http://localhost:3000/workouts/userId
+
+## Conclusion
+
+Congratulations! You have built a simple fitness app similar to Fitbud. You can now extend this app by adding more features such as goal tracking, progress monitoring, and more. Happy coding!