js0mmer/pismartled-server

A Socket.IO server for controlling a pi-connected LED strip

pismartled-server

A simple Socket.IO server for interfacing with a pi-connected LED strip. This project also includes a basic web interface to toggle the LEDs which can be expanded upon.

Table of Contents

• Getting Started
  • Prerequisites
  • Setup
  • Development
  • Production
• Communicating with the socket
  • Examples

Getting Started

Prerequisites

• Node.js
• Yarn

Setup

1. Clone the repository onto your pi and enter the directory

git clone https://github.com/js0mmer/pismartled-server pismartled && cd pismartled

2. Install node packages

yarn

3. Copy .env.example to .env and edit your port numbers with your text editor of choice. You should have the - end of your LED strip connected to ground and the + end to the GPIO port defined in .env. Here is a pinout diagram for reference. The number you define GPIO_PORT to should be the number that appears on the label GPIO ## in the first image, not the number within the circle.

cp .env.example .env
nano .env

Development

To run the project, simply run

yarn start

If everything was installed correctly, you should be able to view the web interface at http://your-pi-ip:port

Production

You'll want to set up a systemd service for the project to run in the background and on startup.

1. Copy the pismartled.service file to the systemd services folder

sudo cp pismartled.service /etc/systemd/system/pismartled.service

2. Open up the file you copied with your text editor of choice and verify that the working directory is correctly configured.

sudo nano /etc/systemd/system/pismartled.service

3. Start the service and enable automatic startup on boot

sudo systemctl start pismartled
sudo systemctl enable pismartled

If everything is working correctly, you should be able to view the web interface at http://your-pi-ip:port

You can also view the logs with

journalctl -u pismartled

Communicating with the socket

To control the LED from a client, simply run

socket.emit('led', 1);

or

socket.emit('led', 0);

where 1 is on and 0 is off.

Upon receiving an update to the LED, the server will emit an led event to all clients with the new value to keep them updated. A client can listen to updates by listening to the led event.

socket.on('led', data => {
  if (data == 1) {
    console.log('The light has been turned on!')
  } else if (data == 0) {
    console.log('The light has been turned off!')
  }
});

A client can retrieve the current status of the LED by emitting the status event and listening to a response on the led event

socket.emit('status');

socket.on('led', data => {
  if (data == 1) {
    console.log('The light is currently on!');
  } else if (data == 0) {
    console.log('The light is currently off!');
  }
});

Examples

Check out pismartled-android