This begins a short series on Azure Functions and Durable Functions from the perspective of building APIs. This is based on material from my book Programming APIs with C# and .NET that I wrote with Joseph Dluzen (to tell the truth, the Functions chapters were initially written by Joe!)
Understanding Functions – Don’t Panic
Azure Functions are very important when focusing on event-driven data processing. Functions allow for ease of development, deployment and scaling. Functions are considered to be serverless in that you don’t have to manage individual instances.
The main way to execute an Azure Function is with a trigger. There are a variety of triggers, what they have in common is that they all react to external events: e.g., queue polling to ServiceBus pushing. They can also react to blob or Database record changes. For APIs we mostly care about HTTP triggers.
HTTP triggers are fired by a request-response to a normal API request. These requests come from a browser, or webhooks, service calls and etc. They are routed to individual functions using built-in routing templates.
There are a number of ways to host functions, including (and especially) Docker. (More on Docker in a future post), as well as Zip files.
Next: a walk through of creating a new Functions project.
