SpotiApp

A local Shiny app to analyze and reorganize your Spotify playlists using clustering.

What it does

Clustering tab

• Select up to 2 of your playlists
• Run k-means or DBSCAN clustering on their tracks using artist and track features (popularity, duration, explicitness, release year, artist popularity, genre tags)
• Browse results by cluster, see a feature comparison chart, download clusters as CSV, or save them directly as new private playlists in your Spotify account

Backup tab

• Export any of your playlists as CSV
• Or download all of them at once as a ZIP (one CSV per playlist)

Tech stack

Package	Role	Why
shiny	Web framework	Reactive UI in pure R, no separate backend needed
httr	Spotify API + OAuth2	Direct API access; spotifyr's audio features endpoint returns 403 on new apps, so we call /v1/artists ourselves
spotifyr	Auth helpers only	get_my_playlists() and get_my_profile() — kept for convenience
DT	Interactive tables	Sortable, searchable tables with zero config
plotly	Lollipop chart	Interactive via ggplotly(), tooltip shows real values
dbscan	DBSCAN clustering	Density-based alternative to k-means; doesn't require choosing k, isolates noise tracks
zip	Multi-file export	Bundles multiple CSVs into a ZIP for the full backup
renv	Dependency management	Reproducible installs for anyone who clones the repo

Key decisions:

• No audio features endpoint: Spotify deprecated /v1/audio-features (403 on apps created after ~2024). Features are derived from /v1/artists (popularity, genres) and track metadata (duration, explicit, release year).
• Local only: OAuth via httr works fine locally. No deployment needed.
• k-means + DBSCAN: k-means is the simple baseline (you choose k). DBSCAN is offered as an exploratory alternative when you don't know how many groups exist — tracks that don't fit any cluster are labeled "Unclassified" rather than forced into a group.

Setup

1. Spotify credentials

Go to developer.spotify.com, create an app, and copy the Client ID and Client Secret. Under the app settings, add this Redirect URI:

http://127.0.0.1:1410/

Create a .Renviron file in the project root (use .Renviron.example as reference):

SPOTIFY_CLIENT_ID=your_client_id
SPOTIFY_CLIENT_SECRET=your_client_secret
SPOTIFY_CLIENT_REDIRECT_URI=http://127.0.0.1:1410/

Restart your R session after saving.

2. Install dependencies

renv::restore()

3. Run the app

shiny::runApp("spotify_app")

Or open spotify_app/app.R in RStudio/Positron and click Run App.

The app opens at http://127.0.0.1:3838. A browser window will prompt you to authorize your Spotify account.