Azure App Service custom sign-in

Implementation of Customized sign-in/sign-out using App Service Authentication.

Interface that executes the authentication flow:

1 - Create the infrastructure

Create the App Service resorces:

az group create -n rgapp -l eastus
az appservice plan create -g rgapp -n planapp --is-linux --sku B1
az webapp create -g rgapp -p planapp -n appcustomsignin789 -r "DOTNETCORE:7.0" --https-only
az webapp config set -g rgapp -n appcustomsignin789 --always-on true

Add the required app settings (environment variables):

az webapp config appsettings set -g rgapp -n appcustomsignin789 \
        --settings WEBSITE_RUN_FROM_PACKAGE=1

Set up CORS:

az webapp cors add -g rgapp -n appcustomsignin789 --allowed-origins "*"

Restart the app:

az webapp restart -g rgapp -n appcustomsignin789

2 - Add Authentication to App Services

Using the Portal, add an identity provider:

• Identity Provider: Microsoft
• App Registration Type: Create new
• Supported account types: Current / Single tenant
• Restrict access: Require
• Unauthenticated requests: HTTP 401
• Token store: No (Uncheck the box)

➡️ Open the configuration and change the Issuer URL to the updated one:

• Issuer URL: https://login.microsoftonline.com/{TENANT_ID}

Make sure the token audiences is configured:

• Allowed token audiences: api://{APPLICATION_ID}

3 - Update the App Registration

Delete the Web App platform.

Create a new SPA platform with redirect URI http://localhost:4200.

Do not select any token generation for the Authentication endpoint. This will trigger the app registration to use Auth Code Flow + PKCE.

4 - Deploy the Web API to Azure

Enter the application directory:

cd webapi

Build and deploy the webapi to App Services:

bash build.sh
az webapp deployment source config-zip -g rgapp -n appcustomsignin789 --src ./bin/webapi.zip

5 - Call the APIs

To run the Angular client locally, create the angular\src\environments\environment.development.ts file:

export const environment = {
  production: false,
  APPSERV_ENDPOINT_URL: "https://appcustomsignin789.azurewebsites.net",
  AZUREAD_CLIENT_ID: "{APPLICATION_ID}",
  AZUREAD_TENANT_ID: "{TENANT_ID}"
};

Start the Angular app:

npm install
ng serve

The website should be available at http://localhost:4200

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Destroy the Azure resources to avoid costs.