serverless/docs/providers/azure/guide/intro.md

Serverless Framework - Build web, mobile and IoT applications with serverless architectures using AWS Lambda, Azure Functions, Google CloudFunctions & more

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title: Serverless Framework - Azure Functions Guide - Introduction
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description: An introduction to using Azure Functions with the Serverless Framework.
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### [Read this on the main serverless docs site](https://www.serverless.com/framework/docs/providers/azure/guide/intro)

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# Azure - Introduction

The Serverless Framework helps you develop and deploy serverless applications using Azure Functions. It's a CLI that offers structure, automation and best practices for deployment of both code and infrastructure, allowing you to focus on building sophisticated, event-driven, serverless architectures, comprised of [Functions](#functions) and [Events](#events).

## Core Concepts

Here are the Framework's main concepts and how they pertain to Azure Functions…

### Functions

A Function is an [Azure Function](https://docs.microsoft.com/en-us/azure/azure-functions/functions-reference). It's merely code, deployed in the cloud, that is most often written to perform a single job such as:

- _Saving a user to the database_
- _Processing a file in a database_
- _Performing a scheduled task_

You can perform multiple jobs in your code, but we don't recommend doing that without good reason. Separation of concerns is best and the Framework is designed to help you easily develop and deploy Functions, as well as manage lots of them.

### Events

Anything that triggers an Azure Function to execute is regarded by the Framework as an **Event**. Events are platform events on Azure Functions such as:

- _An HTTP Trigger (e.g., for a REST API)_
- _A scheduled timer (e.g., run every 5 minutes)_
- _A Service Bus Queue trigger (e.g. a workitem from another Function)_
- _An IoT/Event Hub message (e.g., a message from a device or service)_
- _A Webhook fires (e.g., Github project update)_
- _And more..._

When you define an event for your Azure Function in the Serverless Framework, the Framework will automatically translate this into [bindings](https://docs.microsoft.com/en-us/azure/azure-functions/functions-triggers-bindings) needed for that event and configure your functions to listen to it.

### Function App

A **Function App** is the Framework's unit of organization. You can think of it as a project file, though you can have multiple services for a single application. It's where you define your Functions, the Events that trigger them, and the Resources your Functions use, all in one file by default entitled `serverless.yml` (or `serverless.json` or `serverless.js`). It looks like this:

```yml
# serverless.yml

service: users

functions: # Your "Functions"
  usersCreate:
    events: # The "Events" that trigger this function
      - http: true
        name: req
          methods:
            - post
          route: /users/create
  usersDelete:
    events:
      - http: true
        name: req
          methods:
            - delete
          route: /users/delete
```

When you deploy with the Framework by running `serverless deploy`, everything in `serverless.yml` (or the file specified with the `--config` option) is deployed at once.

### Plugins

You can overwrite or extend the functionality of the Framework using **Plugins**. Every `serverless.yml` can contain a `plugins:` property, which features multiple plugins.

```yml
# serverless.yml

plugins:
  - serverless-plugin-identifier
  - serverless-another-plugin
```