Getting started with Azure Functions

Tutorial 1 of 5

Introduction

In this tutorial, we will focus on how to get started with Azure Functions, a serverless solution provided by Microsoft that allows you to run small pieces of code ('functions') without having to explicitly provision or manage infrastructure.

By the end of this tutorial, you'll have learned how to set up your development environment, create your first function, and deploy it on Azure.

Prerequisites:
- Basic knowledge of JavaScript or C#
- Azure account

Step-by-Step Guide

Setting Up Your Development Environment

First, you need to set up the Azure Functions Core Tools on your local development machine. These tools provide a local development experience for creating, developing, testing, running, and debugging Azure Functions.

Installation:

For Windows users, you can use npm:

npm i -g azure-functions-core-tools@3 --unsafe-perm true

For MacOS users, use brew:

brew tap azure/functions
brew install azure-functions-core-tools@3

Creating your First Function

After setting up your environment, it's time to create your first function.

  1. Open your terminal or command prompt and create a new folder for your project, then navigate into it:
mkdir MyFirstFunction
cd MyFirstFunction
  1. Run the following command to create a new function project:
func init
  1. Choose a language for your project (we'll use JavaScript in this tutorial).

  2. To create a function, run the following command:

func new
  1. Select a template for your function. We'll use HTTP trigger for this tutorial.

  2. Finally, provide a name for your function.

Deploying your Function on Azure

After creating your function, the next step is to deploy it on Azure.

  1. Log in to your Azure account using the Azure CLI:
az login
  1. Deploy your function using the 'func azure functionapp publish' command. Replace '' with the name of your function app.
func azure functionapp publish <APP_NAME>

Code Examples

Here is an example of a simple HTTP trigger function in JavaScript:

module.exports = async function (context, req) {
    context.log('HTTP trigger function processed a request.');

    const name = (req.query.name || (req.body && req.body.name));
    const responseMessage = name
        ? "Hello, " + name + ". This HTTP triggered function executed successfully."
        : "This HTTP triggered function executed successfully. Pass a name in the query string or in the request body for a personalized response.";

    context.res = {
        // status: 200, /* Defaults to 200 */
        body: responseMessage
    };
}

In this code:

  • context is an object that provides methods to log information and manipulate the response sent to the function caller.
  • req is an object that contains information about the HTTP request that invoked the function.
  • context.log is used to log information to the console.
  • context.res is used to send a response back to the caller of the function.

Summary

In this tutorial, we've learned how to set up our development environment for Azure Functions, create an HTTP-triggered function, and deploy it on Azure. The next step would be to explore different types of triggers and bindings and how to use them.

Practice Exercises

  1. Create an HTTP triggered function that returns a simple "Hello, World!" message.
  2. Create a Timer triggered function that logs a message every 5 minutes.
  3. Deploy these functions on Azure and verify that they work correctly.

Additional Resources