Book Image

Learning Azure Functions

Book Image

Learning Azure Functions

Overview of this book

Functions help you easily run small pieces of code in cloud with Azure functions without worrying about a whole application or the infrastructure to run it. With Azure functions, you can use triggers to execute your code and bindings to simplify the input and output of your code. This book will start with the basics of Azure Functions. You will learn the steps to set up the environment and the tools that we will be using in the further chapters. Once you have a better understanding of this, we will be creating our first hello world function app. Later you will be introduced to triggers, how they are used to activate a function, and how binding can be used to output results of a function.You will also explore the steps to create an assembly with complex functionality that can be used by functions. Next, this book will teach you to scale your functions and use them to process data, integrate systems, and build simple APIs and microservices. Finally, this book will cover some diagnostic techniques with Azure App services and best practices of working with Azure Functions. By the end of this book, you will be well-versed with the techniques of scaling your Azure functions and making the most of serverless architecture.
Table of Contents (17 chapters)
Title Page
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Customer Feedback
Dedication
Preface

Using an event with an Azure Function


Events are things that trigger our Azure Functions to run. Events can be HTTP endpoints, message queues, blob updates, and cron-scheduled events. To elaborate more by giving an example, what if you want to be notified when a file is uploaded on blob storage or you want to immediately process a file when it is uploaded to blob storage?

The following diagram shows how the Azure Function works, which gets triggered when an event occurs:

The following are the types of event that cause the function to run:

  • HTTP Trigger: This is an event that causes the function to run whenever it receives an HTTP request.
  • Timer Trigger: This type of trigger is run on the basis of a schedule. We can set the time for the trigger and the function runs at that specified time.
  • Queue Trigger: The Azure Function will run whenever a message is added to a specified Azure queue storage.
  • Blob Trigger: The Azure Function will run whenever a blob is added to a specified container, for example...