waifud Progress Report #2

A 21 minute read.

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Image generated by MidJourney -- The legend of zelda breath of the wild, windows xp wallpaper, vaporwave style, anime influences, miyazaki moment

Hey, it's been a while since I wrote the last update on waifud, my cluster-oriented cloud-in-a-box solution for people with too much hardware and not enough things to do with them, and I've gotten a bunch of things done to make using it easier.

I now use waifud for all of my VM needs and it is more than living up to my expectations. I use waifud on stream constantly whenever I need to make a virtual machine as part of explaining concepts. I am slowly working towards a point where other people will be able to install and use it, but I am making sure to take the time to do it right as opposed to just shoving it out of the door and running away.

What is waifud?

waifud is a pet project of mine that I've been working on for over a year now to try and recreate the magic of the cloud on private infrastructure. I wanted to use it as a way to explore what the cloud could be if we re-evaluated all of the design options from scratch and made things conceptually simple. Right now it has two main parts:

  • waifud itself to order around machines running zfs and libvirt
  • waifuctl (waifu-cuddle) to give instructions to waifud with CLI commands.

These two things let me manage virtual machines across my homelab so that I can create fungible virtual machines based on the templates that distributions give to cloud providers. I wanted to see how far I could get by mostly reverse-engineering things and making things up when reverse-engineering failed.

Progress

Over the last 6 months I've managed to land these major features into waifud:

  • The beginnings of a real admin UI in a browser
  • Scrapers for distribution images
  • Addition and removal of a half-baked authentication system using paseto and yubikeys
  • NixOS modules to deploy waifud
  • A better name generator for new instances
  • manpages for waifuctl

Each of these things does a lot to make the waifud experience a lot more refined and easier to deal with. I'm gonna cover each of these in their own sections so that I can go into detail about what was changed, why it exists, and the benefits it brings.

Admin UI

One of the biggest pain points in waifud for me has been the fact that I've needed to SSH into one of my development machines in order to do things with it. This is fine, most of the time I usually have an SSH session open to one of those machines and can easily do what I need while hacking away.

However, reality is not nice enough to fit into clever boxes. Sometimes I want to just quickly "no u"-reboot a virtual machine or take a glance to see where I should put the next instance. In order to scratch that itch, I made an admin UI. Here's a screenshot of its home page:

There's a bunch going on here, so I'm going to do that writer thing where I hold you captive and write a bunch of words to explain what is going on.

Maud

HTML templating is annoying. In the past I've used things like ructe to template HTML from variables passed to it in Rust. This works, but it has a kinda crap user experience. I've been keeping my eye on a library called Maud that lets you do HTML templating a lot easier.

Maud is a rust macro that lets you write rust-like things and have it get turned into HTML for you at compile time. It's really nice and I've wanted to experiment with it more. I use it in waifud for all of the HTML in the admin console.

Breadcrumbs in the navbar

When you start in the admin UI the navbar will show a list of the high level waifud objects that you can peek at. It currently links to the distribution list page and the instance list page. Take a look at the top of the page here:

Mara is hacker
<Mara> Terminology hint! An "instance" in waifud is the combination of a virtual machine, a base image, a machine to run it on, and finally a user-supplied cloud-init configuration.

When you click on something, the navbar will change in order to highlight where you've been. Here's how the navbar looks when you go to the "create an instance" page:

This is implemented on the server side using a combination of some CSS on an unordered list and a clever bit of Rust. The main way that this works is that the base template function signature looks like this:


use maud::Markup;

pub fn base(
    title: Option<String>,
    crumbs: Option<&[(&str, Option<&str>)]>,
    user_data: User,
    body: Markup,
) -> Markup {
  // ...
}

The crumbs type contains a list of tuples with crumb metadata. The tuples have two components in them:

  • The name of the crumb (such as "Instances" or the instance name itself)
  • Maybe the admin UI relative link to the crumb

That is unpacked into this HTML template with Maud:


maud::html! {
    // ...
    ul {
        li { a href="/admin" { "waifud" } }
        @for (name, link) in crumbs {
            li {
                @match link {
                    Some(link) => a href=(link) {(name)},
                    None => span aria-current="page" {(name)},
                }
            }
        }
    }
    // ...
}

This allows me to have the breadcrumbs generated automatically without me having to care about them. It's pretty nice and I hope it will make my life easier when trying to navigate waifud's admin console. Here's the CSS that powers that:


.breadcrumb {
    padding: 0 .5rem;
}

.breadcrumb ul {
    display: flex;
    flex-wrap: wrap;
    list-style: none;
    margin: 0;
    padding: 0;
}

.breadcrumb li:not(:last-child)::after {
    display: inline-block;
    margin: 0 .25rem;
    content: "/";
}

Feel free to steal it.

Xess and cleancss

Like any good hacker, I have my own CSS femtoframework named Xess that I use on basically everything I write. It allows me to have a uniform, brutalist style that people have told me immediately identifies that I wrote or made something. The only major project of mine that does not use Xess is this website. I was going to make it use Xess at some point, but I'm lazy and spend a lot of my free time writing these articles so something has to give.

Xess is very minimal. It's designed to style native HTML components so that you can stop caring about them and focus on the webapp in question. At first, I was using Xess without making any changes to it. Then I wanted to add a little profile picture based on tailauth metadata and make it in the upper right hand corner of the page. At first I just edited Xess like I'm used to, but then I had a spark of brilliance.

Xess has a Nix package that I use in order to help shove it into various other projects. One of the tools that the build process uses is cleancss to minify the CSS within an inch of its life. I recently found out that cleancss supports minifying multiple files into one CSS file and I wrote a terrible script to do that:


#!/usr/bin/env nix-shell
#! nix-shell -p nodePackages.clean-css-cli -i bash

cleancss -o ./xess.css ./src/xess.css ./src/admin.css

I just run that script when I want to test the CSS changes. I was then able to do everything I wanted with ease.

Xeact JSX and TypeScript with Deno

I originally wrote Xeact as a satirical take on React, a JavaScript library that makes it easier to make frontend applications in browsers. One of the things I didn't really understand the point of was JSX, a syntax extension to JavaScript that lets you write HTML inline in JavaScript.

After writing and maintaining applications with Xeact, I understand the point of this. I have recently cursed Xeact with JSX support as a part of writing the admin UI for waifud. I use that with something I completely made up called the "Xeact Component Model" that standardizes the "main logic" for a page. Here is what a waifud admin page's JavaScript can look like:


/** @jsxImportSource xeact */

import { g, r, x, u } from "xeact";

type HipsumProps = {
    type: "hipster-centric" | "hipster-latin";
    sentences: number;
};

const getHipsum = async ({type, sentences}: HipsumProps): Promise<string[]> => {
    const resp = await fetch(u("http://hipsum.co/api/", {
        type, sentences, "start-with-lorem": "1"
    }));

    const text: string[] = await resp.json()
    return text;
}

const Hipsum = ({text}: {text: string[]}) => {
    return (
        <div>
            {text.map(para => <p>{para}</p>)}
        </div>
    );
}

export const Page = async () => {
    let paragraph = await getHipsum({type: "hipster-centric", sentences: 8});
    return (
        <div>
            <h1>Lumbersexual macchiatto</h1>
            <Hipsum text={paragraph} />
        </div>
    );
};

This makes it a lot easier to understand the structure of the pages in question. The default HTML for importing one of those JavaScript libraries will also pull in the Page function for you:


use maud::PreEscaped;

fn import_js(name: &str) -> PreEscaped<String> {
    PreEscaped(format!(
        r#"<script type ="module">
import {{ Page }} from "/static/js/{name}";

const g = (name) => document.getElementById(name);
const r = (callback) => window.addEventListener("DOMContentLoaded", callback);
const x = (elem) => {{
    while (elem.lastChild) {{
        elem.removeChild(elem.lastChild);
    }}
}};

r(async () => {{
  const page = await Page();
  const root = g("app");
  x(root);
  root.appendChild(page);
}});
</script>"#
    ))
}

Combined with the manually inlined Xeact functions there, everything gets taken care of by itself. It's pretty great. These pages also reuse the waifud API as much as possible, which means that I don't have to reinvent the waifud API but outputting to HTML instead.

I'm very happy with what I've done with the waifud admin panel and I hope it will be as useful as the CLI tool long-term.

HTML scrapers for distro images

One annoying thing that Linux distributions do is that they make the links for cloud images change constantly and only have a few images on their site at once. I understand why they do this. Storing all of those images is expensive. This is very annoying with how waifud was implemented previously because the giant dhall file of images and hashes was made under the assumption that everything was permalinks.

Cadey is coffee
<Cadey> They were not.

So now I scrape the HTML with the help of the scraper crate. It does what it says on the tin. It lets you turn HTML into structures you can loop over. I use that and some annoying fiddly code to do things like parse sha256sum files (I have to deal with four variants of sha256sum files at the time of writing).

It does work though, and every so often I run waifuctl distro scrape to update this list. I need to figure out how to automatically run it as part of waifud.

Introduced and removed paseto for authentication

waifud's API is kind of powerful. It lets you manage virtual machines and potentially delete data or make a machine become full of crap. I did not want to be known as that one person that gave people root over the network, so I made a stopgap solution: requiring authentication with paseto tokens. I bootstrapped that authentication with yubikey presses.

Yeah. It was bad. It's no more though. I ripped it all out and now I use Tailscale for authentication in waifud. The high level idea is to do this:

  • Only have your API visible over Tailscale
  • Every time an HTTP request is being processed, do a whois request on the remote IP address with tailscaled
  • There is no step 3

And that's it. I implemented it with this middleware that works as an Axum extractor to grab Tailscale metadata out of requests and annotate them with that metadata. It works really well. If you want to prevent people from accessing the waifud API, deny them access with Tailscale ACLs.

Friendship ended with paseto, now tailauth is my new friend

Better name generation with the power of Territorial Rotbart

The name generation in waifud used to be powered by a bunch of JSON files that had a bunch of data that I scraped out of fandom wikis. It would pick one of those names randomly. However, this is boring and not nearly as unhinged as it could be.

In Xenoblade games there are superbosses called "Unique monsters" that are usually very high level very tough to kill bosses scattered around the world so you are likely to stumble into them and get totally rekt. The naming pattern of these unique monsters is an adjective and a name. This gets you things like Territorial Rotbart, the terrifying monkey of doom that wanders around one of the first areas in Xenoblade Chronicles 2, Gormott.

This is not unhinged enough to make my trollish heart smile, so I took a look at all of the monsters in Xenoblade Chronicles 2 and I found similar patterns. There are usually "adjectives" that modify base monster names and different "adjectives" seem to correlate with different strength tiers of those monsters. So I chucked everything into a blender. Then I added some laundry sauce in the form of all of the names of Blaseball players, every Pokemon I could find, and all of the names of every pony in My Little Pony: Friendship is Magic.

This is unhinged enough to make my trollish heart smile. If you want to run unique-monster for yourself, run this nix run command:


$ nix run github:Xe/waifud/main#unique-monster
sentinel-taisei
wormeater-ekidno
solare-escavalier
denim-gourgeist
officer-ageshu

I may release rotbart as a separate library on crates.io if there is sufficient demand.

waifuctl UX improvements and manpages

waifuctl had an old version of clap. This has been fixed. With this newer version of clap, I can generate manpages.

The waifuctl.1 manpage at an early stage

Coming soon to a cluster near you!

Next Steps

These are the things I want to work on next as part of the first release of waifud, v0.2.0: Sena Kashiwazaki.

Installation instructions

waifud currently runs in a tmux session on one of my development machines. I need to stop doing this, but I am still actively working on it. When I get to a point where I am happy enough with it to not actively work on it all the time, I will get it working on my homelab and then write up how to replicate that. This is badly needed for other people to use it.

Finish the admin UI

The admin UI should be feature-complete and be able to do everything that the waifuctl command can do.

Some kind of crappy marketing site

It would be cool to have waifud.xeiaso.net have a bunch of shitposty marketingspeak to try and hype people up to wanting to use it. This will also end up being the home of the online documentation for the waifud project. I hope the project will be mature enough to be able to accept outside contributions at that point.

isekaid

It would be neat to move the metadata lookups into some kind of metadata service running at 169.254.169.254, like you do in AWS. I've been calling this idea isekaid and was thinking about implementing this component in Go and having it manage its own WireGuard config with a userspace network stack so it can have the magic IP address 169.254.169.254 all it wants.

Write a sphere-packing algorithm to spread load across the cluster

This isn't required for v0.2.0, but it would be nice to have some kind of algorithm automatically suggest a machine to run a new instance on if you don't specify one. I call it a "sphere-packing" algorithm because trying to put compute jobs into computers is like trying to pack spheres in a box. It works, but not too well.

Relicense to MIT

waifud is currently licensed under the terms of the Be Gay, Do Crimes license as a way to ward away companies from using it in this early state. It's not in an early state anymore, so this license isn't helping as much.


I hope this look into what I have been doing with waifud and the like is interesting. I want to make this a tool that I want to use every day and I hope that I can eventually make it into something you can be happy using every day as well.

Numa is delet
<Numa> Xeserv Public Cloud when


This post was written live on Twitch. You can check out the stream recording on Twitch here and on YouTube here.

This article was posted on M08 27 2022. Facts and circumstances may have changed since publication. Please contact me before jumping to conclusions if something seems wrong or unclear.

Series: waifud

Tags: zfs xeact

This post was WebMentioned at the following URLs:

The art for Mara was drawn by Selicre.

The art for Cadey was drawn by ArtZora Studios.