Tag: deno app

Deno uses URL for dependency management and don’t have dependency module folder like Node has.

We can use GitHub to host our modules , if you wish. For that

• Need to create a repository
• Push the changes with Tag

Go to the repository and find module file / mod.ts and open it as raw , copy the url in to your project and use it as

import mod from 'https://raw.githubusercontent.com/manojap/Deno-CLI-create-app-master/master/src/deps.ts'

All of my Deno projects will be published on my GitHub Repo, so keep watching.

Deno is asynchronous JavaScript/TypeScript runtime. If you are not sure how and what’s of Deno, here is the links

• How to install Deno on Windows - Deno tutorial for beginners
• How to install Deno on Ubuntu Linux - Deno tutorial for beginners: how to install Deno on Windows
• Deno : next generation Node - About Deno TypeScript Runtime

Dotenv

dontenv is a musch familiar module for Node users, it is used to create environment variables to store secrets, Uri, port etc.

Deno have two types of module system standard and third party modules. Third party modules are from the opensource community. dontenv is one of them. You can also contribute modules to the third party library.

setup .env

Create a .env file and place the APP_PORT=3002 in the file where main.ts located.

• import the module
• create env constant
• access the values through constant

import { Application }  from 'https://deno.land/x/oak@v6.0.1/mod.ts'; 
import { config } from 'https://deno.land/x/dotenv/mod.ts';
 
const env = config()
const app = new Application();
const PORT = +env.PORT || 3000 //+convert it number  
app.use( ()=>{
    console.log('Hello world');    
});
app.listen({ port:PORT });
console.log(`Server running on port ${PORT}`);

Everything in .env file is string, it is ideal for placing API, urls, dblinks et. We used + to convert the port string to number because deno port should be anumber

To run the app we need two permission one for url and other for reading .env file.

deno run --allow-net --allow-read main.ts

Now jump into the browser access your route http://127.0.0.1/.

To stop the running server use Ctrl+C

All of my Deno projects will be published on my GitHub Repo, so keep watching.

In our base app tutorial we have seen how to create default page for our app. It is not a route, it’s middle-ware. In this example we create some basic routes using oak Router and add it as middle ware using the use method.

• How to create basic deno app - How to create basic app with deno

routes are the pages/links in a site, such as index page, about page, contact page etc

Create routes

We can create Oak router for our app in the same file. But as the application develop, the code become large, so in order to make it simple and easy to handle we keep routes in separate file and later include them as middle-ware to the main application.

In a folder called routes create a file route.ts

import { Router } from "https://deno.land/x/oak/mod.ts";

const router = new Router()

router.get('/', (ctx) => {
  ctx.response.body = 'Home Page'
  ctx.response.status = 200
  
})

router.get('/about', (ctx) => {
  ctx.response.body = 'About Page'
  ctx.response.status = 200
  
})

router.get('/products', (ctx) => {
  ctx.response.body = 'Products Page'
  ctx.response.status = 200
  
})

export default router;

In the first line we import the Router from the Oak module, which is used to create our basic site routes. Then we export the router and will call the routers in the main.ts as follows.

Here ‘/’ route is the default page / index page of our app.

Arrow function

Every routes carry a function (ctx) =>, which is arrow function (feature of js and ts) having a context argument.

In bigger applications the functions are separated from routes and placed under folder controllers.

Each route can send message as response , also send a status code (which can be seen using developer tools) .

//main.ts
import { Application } from "https://deno.land/x/oak/mod.ts";
import router from './routes/route.ts'
const app = new Application();

app.use(router.routes())
app.use((ctx) => {
    ctx.response.body = "Not found";
});

app.listen({ port: 8000 });
console.log('Server running on port 8000')

In the main.ts we added the route as middle ware, lets run the app with net permission.

deno run --allow-net main.ts

Now jump into the browser access your route http://127.0.0.1/.

To stop the running server use Ctrl+C

All of my Deno projects will be published on my GitHub Repo, so keep watching.