How to Deploy a SvelteKit Web Application on Ubuntu

Updated on October 16, 2023

Introduction

SvelteKit is a web application framework that simplifies the process of building efficient and high-performance web applications. It's based on the Svelte JavaScript framework and offers a complete solution for building web applications that include routing, server-side rendering, and a flexible architecture.

This article explains how you can deploy a SvelteKit web application on a Vultr Ubuntu server. You will deploy a sample application that implements the Wordle game and secure your SvelteKit project with HTTPS to secure client requests on the server.

Prerequisites

Before you begin:

Deploy a fresh Ubuntu server on Vultr
Set up a Domain A record pointing to the Server IP Address
Using SSH, access the server as a non-root user with sudo privileges
Update the Ubuntu server.

This article uses the following example values. Replace them with your actual server details:

Sudo user: example_user
Ubuntu Server IP: 192.0.2.100
Project domain: sveltekit.example.com
Project name: my-app

Install Node.js Using NVM

Using SSH, access the server as a non-root sudo user
```
 $ ssh example_user@192.0.2.100
```

Download the latest NVM installer script

 $ wget https://raw.githubusercontent.com/creationix/nvm/master/install.sh

Run the installation script

 $ bash install.sh

Output:

 => Downloading nvm as script to '/home/example_user/.nvm'
 => Appending nvm source string to /home/example_user/.bashrc
 => Appending bash_completion source string to /home/example_user/.bashrc

Run the source ~/.profile command to reload the environment variables
```
 $ source ~/.profile
```
Install the latest Node.js version. SvelteKit requires at least version 20.0.0 to run on your server
```
 $ nvm install node
```
Verify the installed Node.js version
```
 $ node -v
```
Output:
```
 v20.7.0
```

Create the SvelteKit Project

Using npm, create a new SvelteKit project my-app

 $ npm create svelte@latest my-app

When prompted, enter y and press Enter to start the project initialization script. Use the Up and Down arrow keys to select an option, then, press Enter to set up the project as displayed in the following output:

 create-svelte version 5.0.6

   Welcome to SvelteKit!

   Which Svelte app template?
   SvelteKit demo app

   Add type checking with TypeScript?
   Yes, using JavaScript with JSDoc comments

   Add type checking with TypeScript?
   Yes, using JavaScript with JSDoc comments

   Select additional options (use arrow keys/space bar)
   none

   Your project is ready!

When successful, switch to the project directory
```
 $ cd my-app
```
Using npm, install the project dependencies
```
 $ npm install
```
Install other project dependency packages
```
 $ npm install dotenv express helmet @godaddy/terminus
```
The above command installs the following packages:
- dotenv: Loads environment variables in a production environment
- express: Creates a custom server that you can run with additional security middleware and server cleanup functions
- helmet: Provides security improvements for the express server functions
- @godaddy/terminus: Provides cleanup functions for HTTP applications

Set Up the SvelteKit Adapter

By default, SvelteKit uses adapter-auto, but it may fail to detect and choose the correct environment. To specify a target environment, use the Node.js adapter as described below.

Install the Node.js adapter-node package

 $ npm install -D @sveltejs/adapter-node

Back up the original svelte.config.js file

 $ mv svelte.config.js svelte.config.ORIG

Using a text editor such as Nano, recreate the file
```
 $ nano svelte.config.js
```

Add the following adapter configurations to the file

 import adapter from '@sveltejs/adapter-node';
 import { vitePreprocess } from '@sveltejs/kit/vite';

 const config = {
     preprocess: vitePreprocess(),
     kit: {
         adapter: adapter()
     }
 };

 export default config;

Save and close the file.

The above configuration implements the Node.js adapter as the default project package. Create the necessary server files to make use of the adapter.

Create a Custom Server

In this section, create a custom server that performs the following functions:

Load environment variables
Enable security improvements
Enable graceful shutdown (automatically close all open connections and run cleanup functions)

Implement these features in a custom server definition file as described below.

Create a new custom server file server.js
```
 $ nano server.js
```

Add the following code to the file

 import 'dotenv/config'

 import { handler } from './build/handler.js';
 import express from 'express';
 import helmet from "helmet";
 import http from 'http';
 import { createTerminus } from '@godaddy/terminus'

 const app = express();

 app.use(
   helmet({
     contentSecurityPolicy: {
       directives: {
         ...helmet.contentSecurityPolicy.getDefaultDirectives(),
         "script-src": ["'self'", "'unsafe-inline'"],
       }
     },
     referrerPolicy: {
       policy: ["same-origin"],
     },
   })
 )

 app.use(handler);

 const server = http.createServer(app)

 createTerminus(server, {
   signals: ['SIGTERM', 'SIGINT'],
   onSignal: async () => {
     // Call your cleanup functions below. For example:
     // db.shutdown()
   }
 })

 server.listen(3000, () => {
   console.log('Listening on port 3000');
 });

Save and close the file.

Build the Project

Using npm, build the project with production variables

$ npm run build

Output:

> my-app@0.0.1 build
> vite build

vite v4.4.9 building SSR bundle for production...
"confetti" is imported from external module "@neoconfetti/svelte" but never used in "src/routes/sverdle/+page.svelte".
✓ 102 modules transformed.

vite v4.4.9 building for production...
✓ 92 modules transformed.
.svelte-kit/output/client/_app/version.json                                                         0.03 kB │ gzip: 0.05 kB

.svelte-kit/output/server/entries/pages/sverdle/_page.server.js                                   146.19 kB

Run npm run preview to preview your production build locally.

> Using @sveltejs/adapter-node
  ✔ done
✓ built in 10.54s

As displayed in your output, verify that a successful build notice ✓ built in 10.54s displays.

Run the Project Using PM2

PM2 is a Node.js package that allows you to run applications as background processes and restart them in case of failures. Using PM2, run the SvelteKit project as described in the steps below.

Using npm, install PM2 as a global package
```
 $ npm install -g pm2
```

Using PM2, start the SvelteKit project using your custom server file

 $ pm2 start server.js

Output:

 [PM2] PM2 Successfully daemonized
 [PM2] Starting /home/linuxuser/my-app/server.js in fork_mode (1 instance)
 [PM2] Done.

View the server logs and verify that the project is running correctly without errors
```
 $ pm2 logs
```
Output:
```
 /home/linuxuser/.pm2/logs/server-out.log last 15 lines:
 0|server   | Listening on port 3000
```
If you want to stop your application:
```
 $ pm2 stop server
```

Configure Caddy as a Reverse Proxy and Enable HTTPS Access

Caddy is a web server package that automatically generates SSL certificates for configured domain entries. To enable HTTPS access on the SvelteKit project, install Caddy and set up the configuration file to connect to the SvelteKit server on port 3000 as described in the steps below.

To install Caddy, add the official repository GPG key

 $ curl -1sLf 'https://dl.cloudsmith.io/public/caddy/stable/gpg.key' | sudo gpg --dearmor -o /usr/share/keyrings/caddy-stable-archive-keyring.gpg

Add the Caddy repository to your APT sources

 $ curl -1sLf 'https://dl.cloudsmith.io/public/caddy/stable/debian.deb.txt' | sudo tee /etc/apt/sources.list.d/caddy-stable.list

Update the server packages to activate the repository changes
```
 $ sudo apt update
```
Install the Caddy web server
```
 $ sudo apt install caddy
```

Back up the default Caddyfile configuration file

 $ sudo mv /etc/caddy/Caddyfile /etc/caddy/Caddyfile.ORIG

Create a new Caddy configuration file
```
 $ sudo nano /etc/caddy/Caddyfile
```
Add the following configurations to the file. Replace sveltekit.example.com with your actual domain
```
 sveltekit.example.com {
   reverse_proxy localhost:3000
 }
```
Save and close the file.
Restart Caddy to apply changes
```
 $ sudo systemctl restart caddy
```
To enable access to the SvelteKit server over HTTPS, allow port 443 through the default UFW firewall table
```
 $ sudo ufw allow 443/tcp
```
Restart the firewall to apply changes
```
$ sudo ufw reload
```
When using additional firewalls such as the Vultr Firewall, allow the HTTP port 443 through the firewall to enable access to the SvelteKit server.

Test the SvelteKit Web Application

Using a web browser such as Firefox, visit your configured SvelteKit domain
```
 https://sveltekit.example.com
```
Verify that your SvelteKit web application displays correctly in the browser
On the top navigation menu, click Sverdle or include it in your URL
```
 https://sveltekit.example.com/sverdle
```
A SvelteKit Wordle game should display. To play the game, enter the keyword apple to continue with your next guess to complete the game.

To further test the game functionality, enter the keyword water to complete the game sequence

If you don't receive any error page, or log entry, your SvelteKit project is running correctly. Configure the project to match your needs and handle site visitor connection requests over HTTPS.

Troubleshooting

If you encounter the following errors while running your SvelteKit project, troubleshoot them as described in the solutions below.

The SvelteKit Website Loads Indefinitely

View the PM2 server logs and verify that no error displays
```
 $ pm2 logs
```
Using Curl, verify that the SvelteKit server runs on the default port 3000 specified in your configuration
```
 $ curl 127.0.0.1:3000
```
Allow the HTTPS port 443 through the firewall
```
 $ sudo ufw allow 443/tcp
```

The SvelteKit Web Application Displays with a Broken Layout and No Styling

The helmet middleware only accepts HTTPS connections to your web application in a production environment. Configure a domain record and generate SSL certificates to use HTTPS on the server. To use the server without a domain record and HTTPS access, remove the helmet parts from your server.js configuration file.

Conclusion

You have deployed a SvelteKit web application on a Vultr Ubuntu server using the latest Node.js version with NVM. Depending on your use case, you can configure your SvelteKit project to run and serve site visitors with ready applications such as the Wordle game applied in this article. For more information, visit the SvelteKit documentation.

How to Deploy a SvelteKit Web Application on Ubuntu

Introduction

Prerequisites

Install Node.js Using NVM

Create the SvelteKit Project

Set Up the SvelteKit Adapter

Create a Custom Server

Build the Project

Run the Project Using PM2

Configure Caddy as a Reverse Proxy and Enable HTTPS Access

Test the SvelteKit Web Application

Troubleshooting

The SvelteKit Website Loads Indefinitely

The SvelteKit Web Application Displays with a Broken Layout and No Styling

Conclusion

Products

Features

Marketplace

Resources

Company