Implementing Rust newtype for errors in axum

Summary

TL;DR: GITHUB REPO. Tired of writing the same verbose error handling boilerplate in your Axum handlers? Me too! 🙄 By creating a custom AppError newtype that wraps anyhow::Error and implements IntoResponse + From<E>, you can ditch all those ugly match statements and embrace the beautiful ? operator. Your handler functions go from messy error-matching shenanigans to clean, readable code that automatically converts any error into proper HTTP responses. It’s like magic, but with more crabs! 🦀 Recently I’ve been digging a lot into the axum crate for any of my Rust web projects. There are plenty of options out there for Rust web applications, but it seems that we have all settled on Axum as the go to crate. Before you even start reading this, if you have not checked it out yet - do so now … I’ll wait. Okay, you’re back! Love it? YES! 🥳 Now, let’s talk about a learning project I am working on. Ever since I’ve discovered htmx I’ve been immersing myself in the world of web development with HATEOAS as my priority. Just the neatness of using hypermedia gives me a rush, and helps me with all that JavaScript fatigue. I do suggest you go and give hypermedia systems a read, a thing I have been doing over the past couple of weeks. So, in the spirit of this book, I was following along with building some hypermedia driven system. But instead of using Python and Flask as stated in the book, I’ve opted to put my crab hat on, and do it in Rust. Like the big boy I am. In this post I wont explain how I did that (link to a post from the future will go here), but rather explain how I used the amazing features of Rust to eliminate a lot of boilerplate code on my side. Errors Errors In order to be a good web builder, you want to make sure to return the proper HTTP status codes. (I’m looking at you 200 OK with an error message). So in my handler functions I make sure to explicitly return the Status code as part of my return tuple. Something like so: Ok((StatusCode::OK, Html("<h1>Hello World</h...