Blog — » Henry J Schmale's Blog

Exposing Pandoc to Create PDFs using AWS Lambda 2024 November 26

I needed an endpoint to convert markdown to a standard PDF for reasons. This is how I made a simple low traffic markdown to pdf converter using AWS Lambda and pandoc. When evaluating solutions I discovered that everything either required webkit or a native LaTeX installation. All options that are painful to maintain from a user perspective for a script I was building. This solution ensures that it will keep working into the future by freezing the dependencies. AWS Lambda is really neat because it will let you put whatever you want inside of a docker image and expose it openly on the internet. The hard part is putting together all the steps and doing the docker stuff. So here’s what I did to make it.

Batman Dialer Part 2 - Hardware Testing 2024 September 12

Lets continue on with my batman dialer project. The entire goal here is to hide a secret control panel in some kind of statue. What that control panel does is completely up in the air. So here’s my current progress. I have gotten the analog rotary dialer working. I have also gotten sound working using the MAX98357A breakout board.

Batman Dialer Project #1 2024 August 21

I want to build a security combination lock out device hidden inside of a statue bust of a later to be determined character1. I want to extend this project to do many different features and be a sort of entertaining puzzle for people to play with. To do that I’ve decided to start a series of blog posts describing my thought process through this, the inspiration, and how I built it. Hopefully you enjoy my description of the process and you find some interest or learn something new from this. I’m debating between Athena, Da Vinci, or some possibly obscure Futurama reference. ↩

Using SQLite Extensions with Gorm 2024 August 10

I’ve been building a site in Golang using Gorm as my object relational mapper because it’s a pain to map things into a struct and use the scan interface. Not really using it as a query builder, but it’s still handy. I recently wanted to use some extensions in my queries to do things like unicode normalization and similar functions. I was also sick of waiting for Cgo compilation times so I switched to a webassembly build of sqlite embedded into my go project.

Using the SQLite Shell the Right Way 2024 July 04

I’ve been using the SQLite shell a lot lately to slice and dice data is slightly too large for excel. It’s a very powerful tool to get SQL on the command line without spinning up a large Postres server, and supports most of the SQL standard with syntax similar to Postgres. It’s super fast and supports loading CSV. I want to talk about some quality of life features in it that you probably don’t know about.

Karlovy Vary Weekend Trip 2024 May 27

One of my colleagues is from Karlovy Vary and told me that it’s a great place to visit. It’s an old school spa town known for its geothermal springs. The water from the springs is fully potable and loaded with minerals. It comes out very warm. I spent the weekend exploring this small town and here’s what I did. I treated this as a normal tourist place to visit. I visited alone, but I think it would be better as a family trip for most people.

Kuttna Hora, The Bone Church, and My Corpse 2024 May 22

The other day my colleague invited me to go to Kuttna Hora. It’s a small town about an hour away from Prague. He described it as a town straight up out of fantasy. He was NOT wrong. It’s such a cool town. We visited 3 separate churches and walked around the town. I had a crisis of my own mortality from one of the churches which I will describe later. The wine was very good too. The weather wasn’t great but we made do. It was still super cool to walk around the town.

Ender’s Game, Revisited Thoughts and Issues 2024 May 08

I used to think that “Ender’s Game” was one of the deepest novels and series I’ve ever read. I’ve since reconsidered my opinion on this significantly. I’ve since decided its quite dumb and overplayed. The characterization of the children is too much. There’s an obsession with hyper intelligent children that isn’t realistic or believable in this day and age. I’ve revised this opinion because I’ve been listening to the audio drama version of it with “Ender’s Game Alive,” it a great audio production with an extremely high production values with a full cast and excellent voice actors. It’s been really nice to revisit this novel and revise my opinions on this novel. Also all spoilers are unmarked and may include details in the other novels. This is not quite a book review, its more a rant about organizations and how to build a stable system.

Unveiling the Risks of sts:GetFederationToken, You Probably Don't Need It 2024 May 02

Let’s talk about sts:GetFederationToken and why we should disable it within our AWS Accounts. This call allows the creation of temporary access credentials that can be associated to any user identity. These credentials are difficult to revoke from the console, and cannot be revoked using the standard deny all credentials created before X time policy. It is much better to use standard built in identity providers like the OpenID Connect for CICD Operations or IAM Identity Center for federated user access. We’ll walk through how this call works, what it was originally intended for, and some threat detection.

How I Updated Ruby on My Arch Box Cause the System One Was Out of Date 2024 April 15

I just moved my laptop to run an arch derivative because I got a new SSD installed for more exiciting projects. To my surprise the current version of ruby in the repos was out of date by 9 months. So I had to learn how to use rbenv in order to build my blog and deploy new posts. It’s just like virtual environments with python, but unfamiliar because I only use ruby because I did this site in Jekyll, and to migrate would defeat the purpose of this site which is to share my writing and show off the cool things I built.

A Diagram to Explain the Various Magic the Gathering Formats 2024 March 26

I was struggling to explain the various formats of magic the gathering to my friend, so I made this diagram using d2lang, a nifty diagram creation language. There’s about 5 commonly played formats on paper and then there’s the digital formats. Each format has different card pools and its own banlist to enhance the health of the meta. Each format may also have different set construction rules, but the only special one is commander.

The Magic of Beer Can Chicken 2024 March 19

Beer can chicken and it’s derivatives are my favorite thing to cook. I have laid out in this post some notes on cooking it well, and how to do it right. It’s not something that is explained easily or obviously. These are my personal notes on how I do it, and will be updated as I learn new things about it.

Linting IAM Policies Automatically in Your Pipeline 2024 February 16

When writing IAM policies there are a lot of concerns that must be taken into account. These JSON documents can be the cause of a lot of hurt when deploying them. People often mess up formating, write overly broad permissions, and just don’t get them perfect the first time. Sure you could use a dumb linter just for JSON, but that doesn’t cover all the potential screw ups. So I want to share a smarter linter I found and how we integrated into our deployment pipeline.

Porting a Linux Program to Run in Browser using Emscripten 2023 December 21

On my infinitely long list of things I wanted to implement one of them was taking a binary and stuffing it into a webpage to run entirely client side. Today I have accomplished just that with my new Atari 2600 IDE. This allows you to write an assembly program entirely in browser and run it without setting up any kind of toolchain on your own machine. The following are my notes on getting emscripten, a way to compile c/c++ to run in browser using llvm and wasm, to generate a binary and interfacing that binary with some vanilla Javascript.

Easy Access of Cloudformation Lambda Environment Variables. 2023 September 11

Sometimes you want to run your lambda function deployed as a cloudformation stack locally for testing purposes but you don’t want to hard code any of the underlying resources into your environment. These resources might be things like DynamoDB tables, SNS topics or SQS urls. Their names aren’t hard coded, and shouldn’t be hard coded otherwise you have a singleton stack. Sometimes you’re just a bit too impatient to spin everything up using the SAM cli, and don’t want to debug docker issues, so this helps.