As enterprises continue to adopt serverless (and Platform-as-a-Service, or PaaS) solutions, they often need a way to integrate with existing resources on a virtual network. These existing resources could be databases, file storage, message queues or event streams, or REST APIs. In doing so, those interactions need to take place within the virtual network. Until relatively recently, combining serverless/PaaS offerings with traditional network access restrictions was complex, if not nearly impossible.
This post will demonstrate how to create an Azure Function with private site access. Private site access refers to a way for resources within a virtual network to reach out to an Azure Function. Configuring private site access ensures that the specified Azure Function is not able to be triggered via the public internet. Instead, the function can only be accessed via a specific virtual network. The function is private to the specified virtual network.