HiFi-Friends: A Distributed Music Sharing System

Description

This is our implementation of a distributed music sharing system as a final project for CS 262: Introduction to Distributed Computing.

Video Demo

Replication and persistence using Paxos demo

Demo2_ReplicationPersistencePaxos.mp4

Synced Audio Play/Pause/Skip demo

Demo1_PlayPauseSkipSynchronization.mp4

Built on

We built a server and client using the socket and threading native Python libraries for our wire protocol implementation.

How to run the app

HiFi Friends can be run cross-platform on multiple machines. However, on MacOS, before attempting to start the service, run

sudo sysctl -w net.inet.udp.maxdgram=65535

in order to change the size of the messages that can be transmitted through UDP ports. To start the service, ensure you are in the root directory, and have created the following subdirectories:

server_0_files
server_1_files
server_2_files

Then, run the servers

python3 src/server_paxos.py -s 0 
python3 src/server_paxos.py -s 1
python3 src/server_paxos.py -s 2 

Connect the clients to the server. Modify the HOST variable of line 15 of client-paxos.py to be the IP address of the server, and update the ports to correspond with the respective machine in machines.py.

python3 src/client_paxos.py

After starting the client and connecting to the server successfully, you will be prompted to input an operation code. The client can used these operations to queue, play, pause, and skip songs as specified below:

Enter Operation Code:
1 -> Upload a song to the server. You will be prompted the file name
2 -> Queue a song to the server. You will be prompted the file name. The song will automatically start playing after the current song finishes (if no song is playing, it will start playing immediately)
3 -> List the songs available in the server. These are the songs that can be queued
4 -> List the current queue
5 -> Pause the current song
6 -> Play the current song
7 -> Skip the current song

Note that when a song is queued, paused, played, or skipped, this affects all clients; i.e., all clients are listening to a synchronized/shared audio stream.

How to run the tests

Navigate into the src directory and run the following command

python3 -m unittest tests

All tests should pass.

Folder Structure

├── src                         # All of the source code is here
|   ├── __init__.py             # Initializes application from config file
|   ├── deprecated              # Deprecated Files
|   |   ├── static     
|   |   │   ├── script.js       # Supporting JavaScript for the client (deprecated)
|   |   │   ├── sound.gif       
|   |   |   └── styles.css      # Supporting style file for the client (deprecated)
|   |   ├── templates           # Supporting templates for Flask app (deprecated)
|   |   |   └── index.html      # HTML files
|   |   ├── music_service.py    # Code for the music service (deprecated)          
|   |   ├── app.py              # Code for Flask client (deprecated)
|   |   ├── client.py           # Code to support the client (deprecated)
|   |   └── server.py           # Code for server (deprecated)
|   ├── client_paxos.py         # Code for the client
|   ├── server_paxos.py         # Code for the server
│   ├── paxos.py                # Code supporting the Paxos algorithm
│   ├── tests.py                # Contains unit tests
│   ├── wire_protocol.py        # Code for defining the wire protocol
│   ├── machines.py             # Code defining the machines and their IPs and ports
|   └── utils.py                # Defines common functions used by the application
├── .gitignore	
├── NOTEBOOK.md                 # Engineering notebook	
└── README.md                   # README