🎵 Music Time Machine

A Python CLI tool that generates a Spotify playlist of the top 50 songs from any week since October 1976. Enter a date, and the app scrapes the charts, finds each track on Spotify, and creates a ready-to-play playlist in your account — automatically.

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How It Works

1. You enter a date (e.g. 1994-11-05)
2. The app scrapes musicchartsarchive.com for the top 50 singles chart of that week
3. Each song is searched on the Spotify API by artist and title
4. A new playlist is created in your Spotify account and all found tracks are added
5. The playlist ID is saved to a local catalog (playlists_catalog.json) for future reference

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Features

• Manual OAuth 2.0 Authorization Code Flow — implemented from scratch without third-party Spotify wrappers (see flow diagram)
• Automatic token refresh — persists access and refresh tokens to disk; refreshes silently when expired
• Retry logic — handles transient API errors (429, 502, 503, 504) with configurable retries and sleep delay
• Date normalization — adjusts any input date to the nearest Saturday (how weekly charts are indexed)
• Input validation — rejects future dates and dates before the chart archive's earliest records (October 1976)
• Local playlist catalog — saves playlist name → Spotify ID mappings to playlists_catalog.json

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Setup

Prerequisites

• Python 3.12+
• A Spotify Developer account with an app created

1. Clone the repo

git clone https://github.com/your-username/music-time-machine.git
cd spotify-time-machine

2. Create and activate a virtual environment

python -m venv venv
source venv/bin/activate        # macOS/Linux
venv\Scripts\activate           # Windows

3. Install dependencies

pip install -r requirements.txt

4. Configure your Spotify credentials

Create a .env file in the project root:

SPOTIFY_CLIENT=your_client_id_here
SPOTIFY_SECRET=your_client_secret_here

In your Spotify Developer Dashboard, add the following Redirect URI to your app settings:

http://127.0.0.1:8888/callback

5. Run it

python main.py

On first run, a browser window will open asking you to log in to Spotify and grant permission. After that, your token is saved locally and reused automatically.

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Usage

Which year do you want to travel to? Type the date in this format YYYY-MM-DD: 1985-07-13

• Dates must be in YYYY-MM-DD format
• Earliest supported date: October 1976
• Future dates are rejected
• Type X at the prompt to exit

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Notes

• Dates must be in YYYY-MM-DD format, between October 1976 and today. Type X to exit.
• Songs not available on Spotify are skipped with a log message.

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Example Output

Access Token Loaded
1.  ('Every Breath You Take', 'The Police')
2.  ('Billie Jean', 'Michael Jackson')
...
Get song URI from spotify: 1/50
Get song URI from spotify: 2/50
...
Total songs URI: 47
Playlist added to the catalog!
Songs added!