Add a backlogged post about Azure Functions and Rust

_posts/2020-07-19-azure-functions-with-irc.md

@@ -0,0 +1,62 @@
+---
+layout: post
+title: "Building an Azure Function to send IRC notifications with Rust"
+tags:
+- rust
+- azure
+- github
+---
+
+
+Delivering a simple payload to IRC is an ideal use-case for Function-based
+cloud computing. Last year when GitHub discontinued their service for pushing
+notifications into IRC channels, I had a perfect situation to couch-hack with a
+library I had recently discovered: [Azure Functions for
+Rust](https://github.com/peterhuene/azure-functions-rs/)
+
+Functions-as-a-Service are a technology which I constantly kick myself for
+liking as much as I do. Functions, Lambdas, or whatever you wish to call them
+are a novel reinvention of [FastCGI](https://en.wikipedia.org/wiki/FastCGI),
+and lots of fun to mock, but like its predecessors: when appropriately used,
+Functions can be incredibly useful. I personally think Functions work well as
+low-throughput "glue". Binding simple services or components together which
+don't warrant an "always-on" application means Functions can make good
+technical and financial sense.
+
+I wrote [this simple function](https://github.com/rtyler/irc-push-function) a
+few months ago, before I actually knew what I was doing with Rust. In the span
+of an evening I was able to cobble something together which would read incoming
+JSON and write information into a [Freenode](https://freenode.net) channel:
+
+```rust
+#[func]
+pub fn webhook(req: HttpRequest) -> HttpResponse {
+    if let Ok(event) = req.body().as_json::<PushEvent>() {
+        info!("Parsed push event from {}", event.sender.login);
+        dispatch_to_irc(event);
+        return "Messages dispatched to IRC".into();
+    }
+    else {
+        return "Failed to parse event".into();
+    }
+}
+```
+
+([it's really simple, I swear](https://github.com/rtyler/irc-push-function/blob/master/src/functions/webhook.rs))
+
+I ended up learning more during this exercise about the Azure Functions Runtime
+For Linux, than Rust itself. Traditional Azure Functions run inside a Windows
+context, which aside from being totally hilarious, is incredibly limiting for
+people wanting to do anything serious that isn't built around C#. The Azure
+Functions for Linux support is exactly how I wish _all_ Functions-as-a-Service
+providers operated: just build the thing into a Docker container. While the
+[Dockerfile](https://github.com/rtyler/irc-push-function/blob/master/Dockerfile)
+is a bit esoteric, the end result is a conventional container which can be
+shipped off to a registry from a CI process, just like practically everything
+else in my world.
+
+Overall the "irc-push-function" I developed is simple enough, runs without a
+hitch, and hasn't cost much of anything the entire time it has been running.
+If you're already running workloads in Azure, I certainly recommend trying out
+[azure-functions-rs](https://github.com/peterhuene/azure-functions-rs/).
+