Azure app service - how do I whitelist an endpoint (not IP address)

Question

I have Azure app service (Web API) and have restricted access to everyone and allowed access by Ipaddress using access restrictions ( https://docs.microsoft.com/en-us/azure/app-service/app-service-ip-restrictions )

I want to allow a particular domain/endpoint access to the API doesn't matter which IP address they are coming from. Is there any way possible to do it.

Answer 1

Unfortunately, It's impossible to whitelist a particular domain/endpoint to the Azure app service using access restrictions as essentially the domain name will be resolved to a real IP address via DNS when the client access the web API in the Azure app service.

Not sure why you want to only allow a particular domain. Perhaps, you just want to map a custom domain to Azure App Service . Then you can access the web API using your multiple custom domain URLs.

Furthermore, optionally, you could apply an Application gateway in front of your web API, then you could access your backend web API using a custom domain URL or Application gateway URL. Application Gateway can make routing decisions based on additional attributes of an HTTP request, for example, URI path or host headers. Also, you could whitelist the Application gateway frontends in your app service access restrictions. See Configure App Service with Application Gateway for more details.

I hope it's helpful for you.