Unlock the Power of Deno: Building a SMTP Mail Client
Deno, the brainchild of Ryan Dahl, the creator of Node.js, is a revolutionary runtime for JavaScript and TypeScript. With its V8 JavaScript engine and Rust foundation, Deno offers a unique approach to building applications. One of its standout features is its first-class TypeScript support, making it easy to set up and use.
No Package Manager? No Problem!
Unlike Node, Deno doesn’t rely on a package manager. Instead, it uses URLs to host and import packages. While this approach has its pros and cons, it offers a fresh perspective on building applications.
Building a Deno Application
In this tutorial, we’ll create a Deno application that sends mail to another user using Deno’s SMTP mail client. To follow along, you’ll need a basic understanding of JavaScript, a text editor (we’ll be using VS Code), and POSTMAN installed on your local machine.
Installing Deno
The easiest way to install Deno is by using HomeBrew. Simply open up your terminal and type:
brew install deno
When the installation is complete, run deno on your terminal to confirm that it was successful.
Setting Up the Deno Server
Next, let’s set up a server for our application. We’ll use Oak, a middleware framework for Deno’s HTTP server that also supports routing, to build our server. Create a server.ts file and add the following code:
import { Application } from 'https://deno.land/x/oak/mod.ts';
const app = new Application();
app.listen({ port: 3000 });
Creating Routes
Now, let’s create a routes.ts file to define our routes, which will communicate with a controller file. Add the following code:
import { Router } from 'https://deno.land/x/oak/mod.ts';
const router = new Router();
router.get('/', (ctx) => {
ctx.response.body = 'This is the home route.';
});
Implementing the Mailer Function
Next, we’ll create a controller.ts file to define our route method. Add the following code:
import { mailer } from './mailer.ts';
export async function sendMail(ctx: Context) {
const body = ctx.request.body();
const mailerObj = new mailer();
await mailerObj.sendMail(body);
ctx.response.body = 'Mail sent successfully!';
}
Setting Up the Deno SMTP Client
Create an index.ts file and add the following code to set up the Deno SMTP client:
import { SmtpClient } from 'https://deno.land/[email protected]/net/smtp.ts';
const smtp = new SmtpClient();
smtp.connect({
hostname: 'mtp.gmail.com',
port: 587,
username: Deno.env.get('GMAIL_USERNAME'),
password: Deno.env.get('GMAIL_PASSWORD'),
});
Using Environment Variables
To store sensitive configuration details securely, let’s modify our code to use environment variables. Create a .env file in the root of the application and add the following:
[email protected]
GMAIL_PASSWORD=your_password
Testing the Application
To test the application, open up POSTMAN and make a post request. After making the request, you can open up the receiver’s mail to confirm that the mail was sent.
Security Best Practices
Remember to store sensitive configuration details in environment variables for better security. Also, always create an .env.example file with the same keys stored in the .env file but without values, and add the .env file to the .gitignore file.
By following this tutorial, you’ve learned how to set up a Deno application that sends mail using the Deno SMTP client. With its ease of use and flexibility, Deno is an exciting new player in the world of JavaScript runtimes.