Azure Functions

Introduction

• Azure Functions is a serverless compute service that allows you to run event-driven code without provisioning or managing infrastructure.
• It supports multiple programming languages and integrates seamlessly with other Azure services.

Triggers and Bindings

Triggers:

• Triggers cause a function to run.
• A trigger defines how a function is invoked and a function must have exactly one trigger.
• Triggers have associated data, which is often provided as the payload of the function.
• Common Types:
  1. HTTP Trigger
  2. Time Trigger
  3. Blob Storage Trigger
  4. Queue Trigger

Bindings:

• Binding to a function is a way of declaratively connecting another resource to the function; bindings may be connected as input bindings, output bindings, or both.
• Data from bindings is provided to the function as parameters.
• Binding Types:
  1. Input Binding
  2. Output Binding

Pricing Plans

Consumption	Premium Plan	App Service
Billing: a. Number of Executions b. Executino Time c. Memory Used d. Free Quota per month	Billing: a. Number of Core Seconds b. Memory Used c. Pre-warmed instances	Billing: a. Pay for App Service resources
Use Case: a. Apps requires scaling b. Intermittent traffic	Use Case: a. Apps that run continously b. Apps require more time	Use Case: a. Existing under-utilized VM’s b. Custom images to run functions

Azure Function Benefits

1. Simplified Programming Model
   • Easily run small pieces of code in cloud.
   • Eliminate bolier plate code
2. Choice of Language
   • Use it to run code in different programming languages
3. Pay-per-use Pricing Model
   • Only pay for the time the code runs
4. Bring Your Own Dependencies
   • NPM, NuGet and other package managers
5. Scales Automatically
   • Parallel invocation to meet demand
6. Open Source Code
7. Docker Runtime
   • Run function runtime in docker on premise or in other clouds
8. Serverless
9. Low Cost Prototyping
   • Quickly creates prototypes at low cost

Programming Language Support

• Below are the supported lanaguages in Azure Functions:
  1. C#
  2. JavaScript
  3. F#
  4. Java
  5. Powershell
  6. Python
  7. TypeScript

Azure Function Authorization Levels

1. Anonymous
   • No Key required.
   • Function can be called by anyone on the internet.
2. Function
   • Function or host key is required.
   • Function is scoped to a specific function.
   • Host key is scoped to all the functions within function app.
3. Admin
   • Master Key required.
   • Provides admin level privileges.
   • Should not be shared or used in client applications.

Use Cases

1. API creation
   • Quick secure API creation with HTTP triggers.
2. Serverless Mobile and Web Backend
   • API, Databases, Queues, etc.
3. Real Time Stream Processing
   • Analysis of telemetry data from cloud applications
4. IoT Data Processing
   • Analysis of IOT stream data
5. ETL