# Sample Functions

Functions are blocks of code that run on demand without the need to manage any infrastructure. Develop on your local machine, test your code from the command line (using `doctl`), then deploy to a production namespace or App Platform — no servers required.

These repositories contain sample functions that you can [deploy as components to App Platform](https://docs.digitalocean.com/products/app-platform/how-to/manage-functions/index.html.md). Each repository contains the necessary `app-spec.yaml` for App Platform and the requisite [project structure](https://docs.digitalocean.com/products/functions/how-to/structure-projects/index.html.md), including `project.yml`.

## Node.js Example Projects

[JavaScript Hello, World!](https://github.com/digitalocean/sample-functions-nodejs-helloworld): This repository contains a project with a sample “Hello, World!” function written in Node.js JavaScript.

[QR Code Generator](https://github.com/digitalocean/sample-functions-nodejs-qrcode): This repository contains a project with a sample QR code generator function written in Node.js JavaScript.

## Python Example Projects

[Python Hello, World!](https://github.com/digitalocean/sample-functions-python-helloworld): This repository contains a project with a sample “Hello, World!” function written in Python.

[Jokes API](https://github.com/digitalocean/sample-functions-python-jokes): This repository contains a project with a sample API that returns jokes written in Python. It includes Pip requirements and a build script.

[Twilio SMS API](https://github.com/digitalocean/sample-functions-python-twilio-sms): This repository contains a project with a sample API that sends SMS messages using Twilio written in Python.

[SendGrid Emails API](https://github.com/digitalocean/sample-functions-python-sendgrid-email): This repository contains a project with a sample API that sends emails using SendGrid written in Python.

## PHP Example Projects

[PHP Hello, World!](https://github.com/digitalocean/sample-functions-php-helloworld): This repository contains a project with a sample “Hello, World!” function written in PHP.

[Numbers to Words API](https://github.com/digitalocean/sample-functions-php-numberstowords): This repository contains a project with a sample API that converts numerals to words written in PHP. It includes a required Composer library and a build script.

## Go Example Projects

[Go Hello, World!](https://github.com/digitalocean/sample-functions-golang-helloworld): This repository contains a project with a sample “Hello, World!” function written in Go.

[MySQL Database](https://github.com/digitalocean/sample-functions-mysql): This repository contains a project with a sample Go function that connects to a MySQL database.

[Spaces Presigned URL API](https://github.com/digitalocean/sample-functions-golang-presigned-url): This repository contains a project with a sample API that returns a presigned URL to upload or download a file to or from a DigitalOcean Space written in Go.