What response data required for Mandatory Customer data request Web hook

[SteveBurns]

We are receiving Notification to implement Mandatory GDPR Web hook for our existing Shopify App, since there are 3 mandatory GDPR web hook
1. Customer data request
2. Customer data erasure
3. Shop data erasure
wherein we receives Customer data request,
so we have some queries for Customer data request,
what would be the customer data payload format and the file type,
also want to know the endpoint where we will have to Post those Customer data.
Please let us know so that we could send and test that webhook.