Azure Functions Documentation

Build and run event-driven applications without managing infrastructure.

Introduction to Azure Functions

Azure Functions is a serverless compute service that enables you to run code on-demand without explicitly provisioning or managing infrastructure. With this fully managed platform, you can trigger your application using various sources, such as HTTP requests, timers, or messages from other Azure services.

Key benefits include:

  • Event-Driven: Respond to events from a wide range of Azure and third-party services.
  • Scalable: Automatically scales based on demand, from a few requests per day to thousands per second.
  • Cost-Effective: Pay only for the compute time you consume.
  • Choice of Languages: Support for popular languages like C#, Java, JavaScript, Python, and PowerShell.

Key Features

Triggers & Bindings

Easily connect your functions to other services with declarative triggers and bindings, reducing boilerplate code.

Serverless Architecture

Focus on writing code, not managing servers. Azure handles the underlying infrastructure and scaling.

Language Support

Develop in your preferred language with excellent tooling support across the board.

Scalability

Automatically scales to meet the demands of your application, ensuring high availability.

Cost Optimization

Benefit from a pay-as-you-go model, making it an economical choice for many workloads.

Timer Triggers

Schedule your functions to run at specific times or intervals, perfect for background tasks.

Getting Started

1. Create an Azure Functions Project

You can create a new project using the Azure Functions Core Tools, Visual Studio, or Visual Studio Code. For example, using the Core Tools:

func init MyFunctionProject --worker-runtime dotnet --docker

2. Develop Your Functions

Write your function code, defining triggers and bindings. Here's a simple HTTP-triggered JavaScript example:

module.exports = async function (context, req) {
    context.log('JavaScript 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. Pass a name in the query string or in the request body for a personalized response.';

    context.res = {
        body: responseMessage
    };
};

3. Deploy Your Functions

Deploy your function app to Azure using the Azure portal, Azure CLI, or CI/CD pipelines.

Use the Azure CLI to deploy:

az functionapp deployment source config-zip -g  -n  --src-zip ./MyFunctionProject.zip

Common Use Cases

  • Web APIs: Build lightweight RESTful APIs.
  • Real-time Data Processing: Process streaming data from IoT devices or queues.
  • Scheduled Tasks: Run background jobs at regular intervals.
  • Event Processing: React to events from databases, storage, or messaging services.
  • Orchestration: Coordinate workflows across multiple functions using Durable Functions.