How to Dockerize a Deno app 👀

Recently, I was in Developer Communities Whatsapp's groups talking about new technologies, many of them were telling me about a new one created by the creator of Node.js…

Wait… what was its name again? Deno? What Deno is?

Deno is a modern and secure runtime for JavaScript and TypeScript that uses V8 Javascript Engine and it's built in Rust, made by the Node.js creator, Ryan Dahl. Today we'll build a simple Deno App and make a container with it.

What will you need to succeed?

• Docker installed on your PC.
• Deno Installed on your PC.
• Git… maybe?

(PD: Could be a MacOs Machine too) :D

So…. Let's start!

1. Create a new folder and add a new file, the name will be "Main.ts".
2. Let's make a "Hello World" server for testing purposes; paste this code on your Main.ts:

import { serve } from "https://deno.land/std/http/server.ts"

const port:number = 42069;
const server = serve({ port: port});

const url:string = "http://localhost:" + port;

console.log('Server running on: ' + url );

for await(const req of server){
    req.respond({ body: "Hi, guys from #DenoDominicana, this is a Hello World server example."});
}

1. Let's run this on your terminal window!

If we open "http://localhost:42069" on our browser, we can confirm that the server is up and running.

Now we know everything is running cool and smooth, let's create a new Docker Container with our server. :D

1. Create a new dockerfile.

1. Paste this:

FROM hayd/alpine-deno:1.2.2

EXPOSE 42069

WORKDIR /app

USER deno

COPY . .
RUN deno cache main.ts

CMD ["run", "--allow-net", "main.ts"]

This dockerfile ensures to use an image named "hayd/alpine-deno" to use Deno in our pc without even install it!

1. Let's build and run the dockerfile on the terminal window; write the following command and hit enter.

docker build -t app . && docker run -it --init -p 42069:42069 app

Now the app is running inside a docker container

and when we go to "http://localhost:42069" in our browser, the server is running without problems.

With this approach, we can achieve a lot of advantages isolating your Deno backend and putting it run on whatever environment you want thanks to Docker.

Take a look to the Repository on Github.

🔗 https://github.com/kevinHernandez05/DockerizeDenoApp