Azure Communication Services callback issue

Question

Hi Team,

We are trying to integrate Azure Communication Services (ACS) within one of our applications. We have deployed a node app on our AKS cluster and this node app uses the ACS SDKs to use ACS to make a phone call.

We are able to make the phone call however we are not receiving any call events to our callback API. This callback API has been provided to ACS as the callback URI parameter in order to receive the call events. As per the documentation here https://learn.microsoft.com/en-us/azure/communication-services/how-tos/call-automation/secure-webhook-endpoint?pivots=programming-language-javascript we have followed all the instructions and have an external public endpoint (deployed on APIM) that we use for the callback.

The documentation mentions that we need to send an API keys as part of the request to ACS. But it does not mention the query parameter key that needs to be used which will carry our auth token forward. Could you provide any advice here?

Specifically around this paragraph

"A common way you can improve this security is by implementing an API KEY mechanism. Your webserver can generate the key at runtime and provide it in the callback URI as a query parameter when you answer or create a call. Your webserver can verify the key in the webhook callback from Call Automation before allowing access"

Thanks,

Vyas