Deploying to Deno Deploy

Introduction

Deno Deploy lets you put your Deno apps on the internet quickly. It makes your code available to anyone through a web address.

You want to share a small web app or API with friends or users.

You need to test your Deno code live without setting up servers.

You want to host serverless functions that run on demand.

You want a fast and simple way to publish your Deno projects online.

Syntax

Deno

deno deploy [project-name-or-url]

Use this command in your terminal inside your project folder.

You need to be logged in with your Deno account to deploy.

Examples

This deploys your current folder as a project named 'my-first-app'.

Deno

deno deploy my-first-app

This deploys a project directly from a GitHub repository URL.

Deno

deno deploy https://github.com/username/repo

Sample Program

This simple Deno program creates a web server that responds with a greeting message. Deploying this to Deno Deploy will make the message available on the web.

Deno

import { serve } from "https://deno.land/std@0.201.0/http/server.ts";

serve((_req) => new Response("Hello from Deno Deploy!"));

Important Notes

Make sure your main file is named main.ts or specify the entry file when deploying.

Deno Deploy automatically handles HTTPS and scaling for you.

Check your deployment URL in the terminal after deploying to visit your live app.

Summary

Deno Deploy lets you publish Deno apps online easily.

Use deno deploy command with your project or repo.

Your deployed app runs serverless and is accessible via a URL.

Practice

1. What is the main purpose of deno deploy in Deno?

easy

A. To run Deno scripts locally without internet

B. To install Deno on your computer

C. To create a new Deno project template

D. To publish your Deno app online as a serverless function

Solution

1. Step 1: Understand the command purpose

   deno deploy is used to publish apps online, not for local installs or running scripts.

2. Step 2: Match the description to the command

   Publishing as serverless functions matches the description of deno deploy.

3. Final Answer:

   To publish your Deno app online as a serverless function -> Option D

4. Quick Check:

   deno deploy = publish app online [OK]

Hint: Remember: deploy means publish online [OK]

Common Mistakes:

• Confusing deploy with install
• Thinking deploy runs code locally
• Assuming deploy creates projects

2. Which of the following is the correct command to deploy a Deno project located in the current folder?

easy

A. deno deploy --install

B. deno deploy .

C. deno run deploy

D. deno start deploy

Solution

1. Step 1: Identify the correct deploy syntax

   The command deno deploy . tells Deno to deploy the current folder project.

2. Step 2: Check other options for correctness

   Options B, C, and D are invalid commands for deployment.

3. Final Answer:

   deno deploy . -> Option B

4. Quick Check:

   Deploy current folder = deno deploy . [OK]

Hint: Use dot (.) to deploy current folder [OK]

Common Mistakes:

• Using deno run instead of deno deploy
• Adding wrong flags like --install
• Using deno start which is not a Deno command

3. Given this command run in your terminal: deno deploy https://github.com/user/myapp, what will happen?

medium

A. Deno will deploy the app from the GitHub repo URL as a serverless app

B. Deno will clone the repo locally but not deploy

C. Deno will throw a syntax error because URLs are not allowed

D. Deno will run the app locally without deploying

Solution

1. Step 1: Understand deploying from a repo URL

   Deno Deploy supports deploying directly from GitHub repo URLs.

2. Step 2: Analyze the command behavior

   The command deploys the app serverlessly from the given URL, no local clone or syntax error occurs.

3. Final Answer:

   Deno will deploy the app from the GitHub repo URL as a serverless app -> Option A

4. Quick Check:

   Deploy from URL = deploy serverless app [OK]

Hint: Deploy accepts GitHub URLs directly [OK]

Common Mistakes:

• Thinking deploy clones repo locally
• Assuming URLs cause syntax errors
• Confusing deploy with local run

4. You run deno deploy myapp but get an error saying "No such file or directory". What is the most likely cause?

medium

A. You forgot to install Deno before deploying

B. The internet connection is down

C. The folder or file named 'myapp' does not exist in the current directory

D. You need to run deno run myapp first

Solution

1. Step 1: Interpret the error message

   "No such file or directory" means the path 'myapp' is missing locally.

2. Step 2: Match error to cause

   Since deploy expects a valid path or URL, missing folder causes this error.

3. Final Answer:

   The folder or file named 'myapp' does not exist in the current directory -> Option C

4. Quick Check:

   Missing folder = No such file error [OK]

Hint: Check folder exists before deploying [OK]

Common Mistakes:

• Assuming Deno is not installed
• Blaming internet connection for local file errors
• Confusing deploy with run command

5. You want to deploy a Deno app that uses environment variables securely on Deno Deploy. Which approach is best?

hard

A. Set environment variables in Deno Deploy dashboard and access them via Deno.env.get()

B. Hardcode environment variables in your source code before deploying

C. Pass environment variables as command line arguments to deno deploy

D. Store environment variables in a local .env file and deploy it with your app

Solution

1. Step 1: Understand environment variable best practices

   Hardcoding or deploying .env files risks exposing secrets publicly.

2. Step 2: Use Deno Deploy features

   Deno Deploy dashboard allows secure environment variable setup accessed by Deno.env.get().

3. Final Answer:

   Set environment variables in Deno Deploy dashboard and access them via Deno.env.get() -> Option A

4. Quick Check:

   Secure env vars = dashboard + Deno.env.get() [OK]

Hint: Use dashboard for env vars, not code files [OK]

Common Mistakes:

• Hardcoding secrets in code
• Uploading .env files publicly
• Trying to pass env vars via deploy command