Mixtape

A social music app where friends share songs, build collaborative playlists, and track listening stats.

This is the starter repo for Project 5: Mixtape Bug Hunt. The app has five open issues in its tracker. Your job is to find, fix, and document at least three of them.

---

App Structure

ai201-project5-mixtape-starter/
├── app.py                      # Flask app factory and DB setup
├── models.py                   # SQLAlchemy models for all entities
├── routes/
│   ├── songs.py                # Song sharing, search, and rating routes
│   ├── playlists.py            # Playlist creation and song management
│   ├── users.py                # User profiles, streaks, notifications
│   └── feed.py                 # Friends listening now, activity feed
├── services/
│   ├── streak_service.py       # Listening streak logic
│   ├── feed_service.py         # Friends listening now feed logic
│   ├── search_service.py       # Song search logic
│   ├── notification_service.py # Notification creation and retrieval
│   └── playlist_service.py     # Playlist retrieval logic
├── tests/
│   ├── test_streaks.py
│   ├── test_search.py
│   └── test_playlists.py
├── seed_data.py                # Populates DB with test data
├── requirements.txt
└── .gitignore

The bugs live in the services/ layer. The routes call services — if something is broken in an endpoint, trace it back to the service it calls.

---

Setup

Create and activate a virtual environment:

python -m venv .venv

# macOS / Linux
source .venv/bin/activate

# Windows (Command Prompt)
.venv\Scripts\activate.bat

# Windows (Git Bash)
source .venv/Scripts/activate

Install dependencies:

pip install -r requirements.txt

Seed the database with test data:

python seed_data.py

Run the app:

FLASK_APP=app:create_app flask run

macOS note: If the app starts but requests hang or return connection refused, try http://127.0.0.1:5000 instead of http://localhost:5000. On macOS, localhost sometimes resolves to an IPv6 address that Flask isn't listening on.

Run tests:

pytest tests/

---

The Five Open Issues

#	Title	Affected service
1	My listening streak keeps resetting	streak_service.py
2	Friends Listening Now shows people from yesterday	feed_service.py
3	The same song keeps showing up twice in search	search_service.py
4	I got notified when a friend added my song to a playlist but not when they rated it	notification_service.py
5	The last song in a playlist never shows up	playlist_service.py

Full issue descriptions are in the Project 5 brief. Read them carefully before opening any service file.

---

How to Read the Code

Start with models.py to understand the data model. Then trace a feature through from its route to its service. For example:

• A user rates a song → POST /songs/<song_id>/rate → routes/songs.py → notification_service.rate_song()
• A user views a playlist → GET /playlists/<id>/songs → routes/playlists.py → playlist_service.get_playlist_songs()

Understanding the full call chain is part of the exercise — don't skip to the service file directly.

---

Submission

Create a branch named bugfix/mixtape for your fixes. Each bug fix should be its own commit using conventional format:

fix: correct Sunday boundary condition in streak reset logic

See the project brief for full submission requirements.