Galactus Sync Service

Introduction

This microservice exposes a WebSocket server on port 9595 which allows multiple clients to synchronize the position of their video players. It does this using the sync, status, pause, play, seek, and reset events. When sending a "sync" or "status" request to the server, it will respond with an event of the same name. It will also periodically send status events to clients to synchonize them with changes performed by other clients.

Join

The join event joins a room with the specified room code. This event should be called before status and update events.

Example Request:

{ code: 1234 }

Sync

The sync event responds with a client and server timestamp. This is used to perform an NTP-like timestamp synchronization between the server and clients.

Example Request:

{ timestamp: 1603253848 }

Example Response:

{ clientTimestamp: 1603253848350, serverTimestamp: 1603253848702 }

Status

The status event responds with a server timestamp and associated video position at that timestamp. If the video is currently playing, clients can get a more accurate video position estimation by subtracting the server timestamp from the client timestamp and summing this value with the video position.

Example Response:

{ playing: true, timestamp: 1603253848350, videoPosition: 60120 }

Update

The update event takes a play/pause boolean, a video position, and a server timestamp associated with that video position. Upon calling it, the server will store these values and broadcast them to all other clients in the room.

Example Request:

{ playing: true, timestamp: 1603253848350, videoPosition: 60120 }

Installation

1. Install nodejs and npm at https://nodejs.org if you don't already have it
2. Clone the repository with git clone https://github.com/galactus-player/sync-service
3. Run npm start in the root of the cloned repo