🌱 PoC Azure FrontDoor

PoC to secure Azure Function behind an Azure FrontDoor, gaining load balancing, DSA and WAF capabilities.

TL/DR

Gist containing artefacts: https://gist.github.com/myreli/fd37b6f29957c9b9180bed984ae5f1bd
Total costs R$0.21 on Azure App Service (Due to the serverfarms, all other resources fall into always free services)

Concept

Expose azure apps and functions through a secure FrontDoor instead of direct access (which is insecure) or API Gateway setup (which is a bit more complex, but combining both is a common approach).

Client → Azure FrontDoor → Azure Functions

[File: b5315926-c0ec-43c0-aa3c-99e4eaab82f1]

Deployment

Create a resource group and deploy the template:

az group create --name poc-frontdoor --location "East US"

az deployment group create \
    --resource-group poc-frontdoor \
    --template-file poc.bicep \
    --parameters appName=poc

All parameters are optional:

location defaults to resourceGroup location
appName defaults to auto-generated string
frontDoorEndpointName defaults to auto-generated string

All other resources are deployed using a auto-generated string or its own name, eg:

resource frontDoorOriginGroup 'Microsoft.Cdn/profiles/originGroups'
  name: 'frontDoorOriginGroupName'

resource hostingPlan 'Microsoft.Web/serverfarms'
  name: 'hpe${uniqueString(resourceGroup().id)}'

Testing

Access the app without FrontDoor (the demo public function): [File: faf2cd3f-91fd-4e2b-9378-8fc03cd47de8]
Access the app with FrontDoor (the demo private function): [File: 580d19d6-93b3-40aa-9066-7f263b71eb47]
Access the app trough FrontDoor:[File: 7b4b34da-ab56-4b5f-a1a2-fe56eedbe609]