Azure Functions with VNet integration

Azure Functions is a serverless computing service offered by Microsoft Azure that enables developers to build and deploy applications as small, independent units of code called “functions”. It can be triggered by a variety of sources, such as an HTTP request, a change to a file in Azure Storage, or a message being added to an Azure Service Bus queue, and can be written in a range of programming languages, including C#, F#, JavaScript, and Python.

One of the key benefits of using Azure Functions is the ability to scale on demand. When a function is triggered, Azure automatically allocates the necessary resources to run the function. This means that the function can handle a large number of requests without any additional configuration required by the developer.

In this article, we will look at how to create and deploy an Azure Function, and how to connect it to a virtual network (VNet) to enable private connectivity between the function and other resources within the VNet.

Prerequisites

Before we get started, there are a few prerequisites that you will need:

• An Azure account. If you don’t have one, you can sign up for a free trial at https://azure.com.
• The Azure Functions extension for Visual Studio Code. You can install it from the Visual Studio Code Marketplace.

Creating an Azure Function

To create an Azure Function, follow these steps:

1. Open Visual Studio Code and click on the Azure icon in the activity bar on the left-hand side of the window.
2. Click on the “Create a new project” button.
3. Select “Azure Functions” as the project type, and then click on the “Next” button.
4. Select the desired runtime and language for your function, and then click on the “Next” button.
5. Choose a location for your function project, and then click on the “Create” button.

This will create a new Azure Functions project in Visual Studio Code, with a default function already created for you.

Deploying an Azure Function

To deploy your Azure Function to Azure, follow these steps:

1. In Visual Studio Code, click on the Azure icon in the activity bar on the left-hand side of the window.
2. Click on the “Sign in to Azure…” button, and then follow the prompts to sign in to your Azure account.
3. Once you are signed in, click on the “Create Function App in Azure…” button.
4. In the “Create Function App in Azure” window, enter a name for your function app, and then select the desired resource group and hosting plan.
5. Click on the “Create” button to create the function app in Azure.

This will create a new function app in Azure, and deploy your function to it.

Connecting an Azure Function to a VNet

To connect an Azure Function to a VNet, follow these steps:

1. In the Azure portal, navigate to the function app that you want to connect to a VNet.
2. Click on the “Networking” tab in the left-hand menu.
3. Click on the “Add Virtual Network” button.
4. In the “Add Virtual Network” window, select the desired VNet and subnet, and then click on the “Add” button.

This will enable private connectivity between your function and other resources within the VNet.