Deploying to Deno Deploy - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is Deno Deploy?

Deno Deploy is a cloud platform that runs JavaScript and TypeScript code close to users worldwide, making apps fast and easy to deploy.

beginner

Which command initializes a new Deno Deploy project?

You start by creating your project files locally. There is no special command to initialize a Deno Deploy project, but you prepare your code and then deploy it using the Deno Deploy dashboard or CLI.

intermediate

How do you deploy a Deno script to Deno Deploy using the CLI?

Use the command `deno deploy ` to upload and deploy your script to Deno Deploy. The `--project` flag is deprecated.

beginner

What file types can you deploy on Deno Deploy?

You can deploy JavaScript (.js), TypeScript (.ts), and JSON files. Deno Deploy runs these files directly without needing a build step.

intermediate

Why is deploying to Deno Deploy faster than traditional servers?

Deno Deploy runs your code at the edge, close to users, reducing delay. It also uses modern JavaScript/TypeScript runtime without extra setup, making deployment quick and simple.

What is the main benefit of deploying to Deno Deploy?

A Only supports Python scripts

B Requires complex server setup

C Runs code close to users for faster response

D Needs manual server maintenance

Deno Deploy runs your code at the edge, near users, which makes responses faster.

Which command deploys a script to Deno Deploy?

A deno run <file.ts>

B deno deploy <file.ts>

C npm deploy

D git push origin main

The `deno deploy` command with the file deploys your code to Deno Deploy.

Which file types can you deploy directly on Deno Deploy?

A .js and .ts

B .html and .css only

C .py and .rb

D .exe and .dll

Deno Deploy supports JavaScript (.js) and TypeScript (.ts) files directly.

What is NOT required when deploying to Deno Deploy?

A Using the Deno Deploy CLI or dashboard

B Writing JavaScript or TypeScript

C Having a Deno Deploy project

D Building or bundling your code

Deno Deploy runs your code directly without needing a build or bundle step.

Where does Deno Deploy run your code?

A At the edge, close to users worldwide

B On a central server far from users

C On your local machine only

D Only inside a Docker container

Deno Deploy runs code at the edge, meaning servers near users for faster access.

Explain the steps to deploy a simple TypeScript file to Deno Deploy.

Think about writing code, then using the CLI to send it to the cloud.

Describe why Deno Deploy is a good choice for fast web apps.

Focus on speed, simplicity, and modern code support.

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