[Node.js] Installing on Digital Ocean Tutorial

Installing on Digital Ocean

This tutorial will show you how to setup your web application on Digital Ocean. Prior to this tutorial you should have:

• an account on a Digital Ocean server
• a domain name
• configuration of your domain name so that yourdomain.com points to the IP address of your server
• configuration of your domain name so that *.yourdomain.com likewise points to the IP address of your server.
• the ability to clone repositories from GitHub onto your Digital Ocean server

Install Mongo

Let's install MongoDB on your server. We will use the Ubuntu packages for this. Mongo recommends you use their official packages, but I have never had a problem with the Ubuntu packages.

Run the following:

sudo apt install mongodb

That should be it! You can verify that it is running:

sudo systemctl status mongodb

You should see a status that says active (running). If you ever need to stop, start, or restart Mongo, you can substitute those commands for status.

Setup your website

We need to configure your web server, nginx, so that it has a new server block for this application. Let's assume it is called museum.yourdomain.com. Substitute your own domain as needed.

First, make a directory, where you will store the files, for example:

sudo mkdir /var/www/museum.mydomain.com
sudo chown [username] /var/www/museum.mydomain.com

Next, navigate to the directory where nginx sites are configured:

cd /etc/nginx/sites-available

Create a new file there:

sudo touch museum.yourdomain.com

Edit this file with the editor of your choice. Be sure to use sudo. Put the following there:

server {
  listen 80;
  server_name museum.yourdomain.com;
  root /var/www/museum.yourdomain.com;
  index index.html;
  default_type "text/html";
  location / {
    # Serve static files from the root location above.
    try_files $uri $uri/ /index.html;
  }
  location /api {
    # Serve api requests here. This will connect to your node
    # process that is running on port 3000.
    proxy_pass http://localhost:3000;
    proxy_http_version 1.1;
    proxy_set_header Upgrade $http_upgrade;
    proxy_set_header Connection 'upgrade';
    proxy_set_header Host $host;
    proxy_cache_bypass $http_upgrade;
  }
}

This will setup nginx so that any requests to museum.yourdomain.com go to /var/www/museum.yourdomain.com, except if the request starts with /api. In that case, the request will be routed to your Node server running on port 3000.

This setup is called a reverse proxy. If you want to setup another application, say cp4.yourdomain.com, you can do that, but you need to run the Node server for that application on a different port.

The next step is to link this into the sites-enabled directory:

cd ../sites-enabled
sudo ln -s ../sites-available/museum.mydomain.com .

You should be able to see that this is working properly:

ls -al

You will see something like this:

lrwxrwxrwx 1 root root   34 Mar 14 01:20 museum.mydomain.com -> ../sites-available/museum.mydomain.com

This shows that the file is linked correctly. You can also try using cat to view the file and make sure it looks right.

The final step is to reload nginx so that this configuration takes effect:

sudo nginx -s reload

If nginx fails to reload properly, then most likely you have a syntax error in the configuration for a host, or your soft link (from ln -s) is incorrect. You can view the exact error with:

cat /var/log/nginx/error.log

Install nvm

You have probably already done this for a previous exercise!

Navigate to nvm and find the curl command used to install nvm.

For example:

curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.35.2/install.sh | bash

Then install the stable version of node and npm and use it:

source ~/.bashrc
nvm install stable
nvm use stable

Clone your code

Clone your repository into your home directory. For example:

cd ~/
git [PathToYourRepositoryOnGitHub]
cd [RepoDirectory]

Set up the back end

First install the packages you will need:

cd back-end
npm install

This will find all the packages in package-lock.json and install them into this directory.

Now, edit server.js. We setup node for your local machine. You need to make sure you configure multer in server.js so that it stores files in your public web server directory. For example:

const upload = multer({
  dest: '/var/www/museum.mydomain.com/images/',
  limits: {
    fileSize: 10000000
  }
});

You need to change dest so that it points to the correct directory.

Finally, make sure your server runs:

node server.js

You just want to make sure it starts without errors. Kill it after you check this with control-c.

Set up the front end

Build your public files:

cd front-end
npm install
npm run build

Now copy your public files to /var/www. For example:

cp -rp dist/* /var/www/museum.mydomain.com/

Run node forever

We will use a Node library called forever to run node -- it will keep running even if you log out.

npm install forever -g

Note that we use the -g option to install forever globally. This way it will be available to all apps on our machine.

You can run your server now with:

cd back-end
forever start server.js

You can check its status with:

forever list

Note that this will show the log file where output from server.js will be stored. This will come in handy!

You can also use:

forever stop 0

to stop forever job number 0.

Testing

Everything should be set up. You should be able to browse to your site, e.g museum.mydomain.com and have the site work.

Debugging

If your site is not working, you should (1) look at the JavaScript console, (2) look at the Network tab in Developer Tools, (3) look at the output of the forever log (see above).