Wavespacer

An application that lets you remove unwanted songs from your playlist. Log in with your Spotify account and get started.

Features

• View your most listened-to genres
• Spotify OAuth login
• View your most played song from the last month
• Playlist cleaner that suggests tracks for deletion
• User profile & settings page
• Light mode support

Notice

This was a student project built for a course. The AWS environment that powers the backend will be shut down, and the Spotify API only allows access to approved users. Because of this, the live application cannot be tested or used unless you set up your own Spotify credentials and backend.

Running Wavespacer Locally

To run this project on your own machine, you must create your own backend environment, including both:

• A Spotify Developer application

• A database (local or hosted)

1 Create Environment Variables

Inside /backend folder, create a .env file.

Backend .env should include:

NODE_ENV
SPOTIFY_CLIENT_ID  
SPOTIFY_CLIENT_SECRET
JWT_SECRET
DB_HOST
DB_USER
DB_PASS
DB_NAME
PORT
FRONTEND_URL
ENCRYPTION_KEY

📊 Database Schema

The application uses a relational database designed to store users, their Spotify data, listening history, songs, and the relationships between artists and genres.

User

Field	Type	Description
id	INT (PK)	Internal user ID
cognito_sub	VARCHAR(45)	Cognito user identifier
spotify_user_id	VARCHAR(200)	Spotify user ID
registered_at	DATE	Registration date

---

User_tokens

A user can have multiple tokens (access/refresh).

Field	Type	Description
id	INT (PK)	Token ID
type	ENUM	e.g. spotify_access_token / spotify_refresh_token
token	VARCHAR(1000)	Token value
expires_at	INT	Unix timestamp
User_id	INT (FK → User.id)	Owning user

---

Subscription

Represents a user’s subscription (free or paid).

Field	Type
id	INT (PK)
plan	ENUM('free', 'plus')
start_date	DATE
end_date	DATE
active	TINYINT
User_id	INT (FK → User.id)

---

Song

Songs the user has listened to.

Field	Type
id	INT (PK)
spotify_track_id	VARCHAR(200)
name	VARCHAR(45)
amount	INT
User_id	INT (FK → User.id)
track_image	VARCHAR(300)

---

Play_history

Individual listening events.

Field	Type
id	INT (PK)
played_at	DATETIME(3)
Song_id	INT (FK → Song.id)
User_id	INT (FK → User.id)

---

Artist

Field	Type
id	INT (PK)
name	VARCHAR(45)

---

Genre

Field	Type
id	INT (PK)
name	VARCHAR(45)

---

Artist_Song (Many-to-Many)

Field	Type
Artist_id	INT (FK → Artist.id)
Song_id	INT (FK → Song.id)

---

Genre_Artist (Many-to-Many)

Field	Type
Genre_id	INT (FK → Genre.id)
Artist_id	INT (FK → Artist.id)

---

2 Install and Run the Backend

cd backend
npm install
npm start

3 Install and Run the Frontend

cd frontend
npm install
npm run frontend

Testing the App

Once both servers are running:

1. Open the frontend in your browser

2. Log in with your Spotify Developer test account

3. Begin removing tracks from your playlist

Note: The app only works with Spotify users you have added to your Spotify Developer app.

Tech Stack

Frontend: Angular + TailwindCSS

Backend: Node.js + Express

Database: MySQL

API: Spotify Web API

Additional Notes

• Spotify's API requires whitelisting users for development apps.

• This project was originally deployed on AWS (EC2, RDS) but that infrastructure is now offline.