Spotify-Visualiser-Service

Spotify-Visualiser-Service is a NodeJS application that will allow socket.io clients to connect, provide authentication and will then serve real-time Spotify playback information by polling the Spotify Developer API for playback and track information.

It will then send updates with the following information;

• Playback status - true or false
• Artist and Title of the currently playing track
• Percentage of how much of the current track has been played
• Human-readable timestamp of how much of the current track has been played
• The current music bar of the song
• The current beat of the song
• The current section of the song
• The current tempo of the current section of the song
• The current average loudness of the current section of the song

Depending on a number of factors (in particular, how fast a particular tracks tempo is) this service may send upwards of 4-5 updates per second.

You can find a changelog at the bottom of this page.

Requirements

Absolute minimum requirements are NodeJS to run the application and a MySQL server to store session tokens (and in a future update, cache Spotify track analysis JSON documents to limit API calls).

This tool was built using NodeJS v12.x and MySQL 5.7.x. - I haven't tested it on other versions, it may or may not work, if it does please let me know!

It is highly recommended you proxy access to this service through NGINX (or another suitable product) that can do SSL or rather TLS termination to help prevent MITM attacks. You can find a guide on how to set that up with NGINX here.

You probably want something to keep the process running too, perhaps something like forever or even better, PM2.

You will also need a Spotify Developer App Client ID (which you get by creating an application). This also means you will be bound by the Spotify Developer terms of service.

Installation

Use the NodeJS npm command line tool to install the dependencies. Here's a quick installation guide;

git clone https://github.com/jasongaunt/Spotify-Visualiser-Service.git
cd Spotify-Visualiser-Service/
npm install

After installation, you must copy config.json-sample to config.json, open it in your favourite editor and fill in all the fields.

Next you must set up the MySQL, first we need to create a database and a user;

mysql -u your_db_admin_username -p

CREATE DATABASE spotify_visualiser;
CREATE USER 'spotify_visualiser_user'@'localhost' IDENTIFIED BY 'SECURE_PASSWORD_HERE';
GRANT ALL ON myspotify_visualiser_db.* TO 'spotify_visualiser_user'@'localhost';
FLUSH PRIVILEGES;

Feel free to change the spotify_visualiser, spotify_visualiser_user values, but you must change the SECURE_PASSWORD_HERE value for something more secure!

Finally, import the included SQL schema;

mysql -u your_db_admin_username -p spotify_visualiser < misc/schema.sql

And that's it. You should be ready to rock.

Usage

Launching the application is as simple as running;

nodejs Spotify-Visualiser-Service.js

The application will then launch, and if successful, you should see the following...

[[22:40:02.198]] [LOG]    Attempting to connect to MySQL...
[[22:40:02.442]] [LOG]    Successfully connected to MySQL.
[[22:40:03.063]] [LOG]    listening on *:8081

And once a client has connected...

[[22:40:07.181]] [LOG]    Client Y9cjJ0OmLieuBrTiAAAB connected from 192.168.1.100.
[[22:40:07.211]] [LOG]    Client Y9cjJ0OmLieuBrTiAAAB attempting to log in with session ID cd86d5ccfc26c60a42a204bb61f56824
[[22:40:07.212]] [LOG]    Client cd86d5ccfc26c60a42a204bb61f56824 not found in our poller yet, adding now...
[[22:40:07.215]] [LOG]    Spotify API call for cd86d5ccfc26c60a42a204bb61f56824: /v1/me
[[22:40:07.264]] [LOG]    Spotify API call for cd86d5ccfc26c60a42a204bb61f56824: /v1/me/player/currently-playing
[[22:40:07.374]] [LOG]    Spotify authenticated cd86d5ccfc26c60a42a204bb61f56824
[[22:40:07.378]] [LOG]    Spotify API call for cd86d5ccfc26c60a42a204bb61f56824: /v1/audio-analysis/39ILxwgD5t1TUEyuz9VxGN
[[22:40:07.908]] [LOG]    Spotify API call for cd86d5ccfc26c60a42a204bb61f56824: /v1/me/player/currently-playing
[[22:40:08.533]] [LOG]    Spotify API call for cd86d5ccfc26c60a42a204bb61f56824: /v1/me/player/currently-playing
[[22:40:09.126]] [LOG]    Spotify API call for cd86d5ccfc26c60a42a204bb61f56824: /v1/me/player/currently-playing
...

Stopping the application is as simple as pressing ctrl+c to quit it.

Contributing

Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change.

Please make sure to update tests as appropriate.

License

This software is released under the GNU General Public License v3.0 license, to summarise though;

• You may use this however you see fit, providing you make your source code publicly accessible under this same license so others can learn and give back to the community
• I take no responsibility for any losses that you may incur directly or indirectly using this software, it is provided without warranty and "as-is"

One more note; despite my best intention to make this safe and reliable, do not trust my code (or anyone else's for that matter) without reviewing it first!

Changelog

• May 25th, 2020 - v0.01 - Initial release