RobotSlam Server

This is the RobotSlam Server, written in Node.JS using ECMAScript 2017.

Requirements

• Node v7.6
• Postgres v9.5 (with PostGIS)

Development

During development it is recommended to use nodemon since it automatically restart the application when it detects a file change.

But it's also possible to run it using npm start.

The application uses the ROS_MASTER_URI environment variable to decide on which host it should attempt to connect to.

Production

Prior to deploying, the clientside JavaScript has to be built

npm run client:build

The production environment is an EC2 server, which can be accessed on https://robotslam.thinxmate.com.

The server can then be started in production mode using:

NODE_ENV=production npm start

Configuring Server

For best compatibility with this guide, ensure the server is running Ubuntu 16.04 LTS. It should be fairly trivial to port to newer versions.

Installing VPN

In order to ensure bi-directional communication between the Robot and RobotSlam server they need to be on the same local network. This is easily achieved by setting up a OpenVPN instance.

Installing and configuring OpenVPN is easily achived using https://github.com/Nyr/openvpn-install.

wget https://git.io/vpn -O openvpn-install.sh && bash openvpn-install.sh

Remember to check that the ports used by OpenVPN are open (Security Groups in EC2 settings).

Installing nginx as reverse proxy

sudo npm install nginx

Installing SSL certificate from Lets Encrypt

Follow the instructions at https://certbot.eff.org/#ubuntuxenial-nginx

sudo add-apt-repository ppa:certbot/certbot
sudo apt-get update
sudo apt-get install certbot

Adding configuration to nginx

Create the file /etc/nginx/sites-available/robotslam with the following content.

server {
    listen 80;
    server_name robotslam.thinxmate.com;

    location / {
        return 301 https://$server_name$request_uri;
    }
}

server {
    listen 443 ssl;
    server_name robot.thinxmate.com;

    client_max_body_size 10G;

    location / {
        # Basic authentication
        auth_basic "Restricted Content";
        auth_basic_user_file /etc/nginx/.htpasswd;

        proxy_pass http://localhost:3000;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header Host $http_host;
        proxy_set_header X-Forwarded-Proto $scheme;
        proxy_buffering off;
    }

    ssl on;
    ssl_certificate /etc/letsencrypt/live/robotslam.thinxmate.com/fullchain.pem;
    ssl_certificate_key /etc/letsencrypt/live/robotslam.thinxmate.com/privkey.pem;
    ssl_prefer_server_ciphers On;
    ssl_protocols TLSv1 TLSv1.1 TLSv1.2;
    ssl_ciphers ECDH+AESGCM:DH+AESGCM:ECDH+AES256:DH+AES256:ECDH+AES128:DH+AES:ECDH+3DES:DH+3DES:RSA+AESGCM:RSA+AES:RSA+3DES:!aNULL:!MD5:!DSS;
}

Enable the new site using sudo ln -s /etc/nginx/sites-available/robotslam /etc/nginx/sites-enabled/ and restart nginx sudo systemctl restart nginx.

Installing NVM

In order to ensure we install the correct Node version, we use the Node Version Manager, https://github.com/creationix/nvm.

nvm install 7.*
nvm alias default 7.*

Configuring Systemd (Node.js)

Create the file /lib/systemd/system/robotslam.service with the following content, making sure to replace "<APPLICATION_FOLDER>" with the application path.

[Unit]
Description=Robotslam Node.js application
After=network.target

[Service]
Environment=NODE_ENV=production
Type=simple
User=ubuntu
WorkingDirectory=<APPLICATION FOLDER>
ExecStart=<APPLICATION FOLDER>/start.sh
Restart=on-failure

[Install]
WantedBy=multi-user.target

Manual Deploy

Upload the new version of the project to the server to the APPLICATION FOLDER. Then run the following commands in the APPLICATION FOLDER.

# Install the npm dependencies
$ npm install

# Compile the clientside JavaScript
$ npm run client:build

# Restart the service
sudo systemctl restart robotslam