Welcome to dmuth.org!

“Who disturbs my nap?”

Welcome to my website and blog! It has been been around in one form or another for well over a decade. It’s changed purposes a few times, and at this point is now a mostly tech blog where I share things I’ve learned or made.

Feel free to have a look around, or consider checking out some of the more popular posts I’ve made over the years:

Thanks for visiting, and feel free to reach out if you have any comments or just want to chat!

Behold! A QR Code Generator That Doesn’t Suck!

Awhile ago, I got into QR Codes. I’ve found them increasingly handy because I could make QR codes based on documents that I had stored in Google Docs, and then I could invite people to scan those QR Codes in person if I wanted to share what was in the doc. The QR Codes themselves could be printed out on paper, be saved to my phone and scanned from them, or even put on my Apple Watch.

But I ran into a challenge: creating QR Codes. When I did searches for QR Code generators, most of the ones I found online either generated small QR Codes, had ads, required money, or all three! It was very much Not Fun, and I felt it was a minor injustice that being able to create something as useful as QR Codes was off limits for so many people.

So I decided to create my own.

After reading some tutorials on how to do it, I found one that talked about how to make QR Codes in Python. I then remembered, that I had an app with a bunch of API endpoints available, and it was written in Python! So, I figured, why not add a QR Code generator, expose it as another endpoint, and create a form which submits to that API?

And that’s exactly what I did, you can find the QR Code generator here:

https://httpbin.dmuth.org/qrcode/

This is 100% free with no ads, no tracking, and no spam. Just QR Codes when you want them.

Enjoy!

Mirror on Medium.

Introducing Docker in Vagrant

If you’re a Mac user, you have a few options for running Docker. Aside from Docker’s official client, there also exists Rancher Desktop and Podman. I’ve used them all, and they’re all decent implementations of Docker. However, I ran into some limitations in each platform that are beyond the scope of this post that nonetheless prompted me to try building out my own Docker offering.

Having used VirtualBox and Vagrant before, I found myself wondering if I could use Vagrant to stand up an instance of Docker, proxy connections to Docker over SSH, and mount directories on the host machine’s filesystem.

It turns out I could.

Continue reading “Introducing Docker in Vagrant”

Displaying Your Wireless Network in the Touch Bar on a Macbook

If you have a Macbook laptop, you’re probably familiar with the touch bar. It’s a neat little LED display above the top row of your keyboard that Mac OS/X uses to display context-sensitive widgets. However, you don’t just have to accept the widgets that Apple provides–you can in fact customize the touchbar however you like.

“But why would I want to do this?”, I hear you ask. Well, maybe you need to have a custom status of some kind displayed on your menu bar. For me, it was… wireless networks.

MTMR is my new favorite utility.

That sounds confusing, but hear me out. Sometimes when I am traveling, I get kicked off of whatever wireless network I’m on. I wanted a way to easily determine what network I was on, without having to keep clicking on the wireless icon in my menu bar. I found that the touch bar was a convenient way to do that, and in this post, I will show you how I did it.

First, download an app called MTMR. MTMR stands for “My Touchbar. My rules.” Installation instructions are on that page, but most users will want the dmg file.

Once that’s installed, you can edit the file $HOME/Library/Application Support/MTMR/items.json to change what appears in the menu bar. The contents of the file are JSON, and you can edit this in whichever editor you like. Furthermore, once you save changes, they take effect immediately–no restarts of the MTMR app are necessary!

Continue reading “Displaying Your Wireless Network in the Touch Bar on a Macbook”

I Created an AI Chatbot of Gritty, and it is Horrifying

Living 20 minutes from downtown Philadelphia, I’m a big fan of our hockey mascot, Gritty. Recently I’ve been playing around with a website called character.ai, and one of the neat things that site lets you do is create bots based on characters, real or imaginary. For example, there is one character based on Albert Einstein, and another is based on Darth Vader. So I decided I would create a character based on Gritty.

I immediately regretted that.

The AI powering that site is… frightfully good, to say the least. After seeding the character with just a handful of tweets from Gritty’s Twitter feed, the bot quickly took on a life of its own and said things that I would absolutely expect the real Gritty to say.

For example, let’s start with the no-fly list:

Well then.

Next I asked Gritty about his diet, and the answers the bot gave were concerning, to say the least:

Continue reading “I Created an AI Chatbot of Gritty, and it is Horrifying”

Introducing FastAPI Httpbin

I write a lot of back end code and sometimes have to make use of HTTP endpoints. Sometimes I want to test those endpoints. I used to use httpbin.org for my endpoint testing, but over time noticed that some of the endpoints were returning HTTP 5xx errors. Some investigation reveals that the project seems to be abandoned, with open issues going all the way back to 2017. That’s not so good.

So I decided to build my own.

In this post I’d like to talk about FastAPI Httpbin. But before I can, I need to talk about FastAPI itself. FastAPI is a framework for building high-performance frameworks in Python based on Python type hints. The really neat thing about FastAPI is that your function definition for each endpoint is the source of truth–FastAPI handles argument validation for any calls to that endpoint, and generates the appropriate Swagger documentation for that endpoint.

Continue reading “Introducing FastAPI Httpbin”

Using the Makeresults in Command in Splunk

If you’re been reading this blog for awhile, you’ll know that I’m a big fan of Splunk, and I even went so far as to Dockerize it for use in a lab/testing environment.

CSI: Logfiles

Well today I want to talk about a command in Splunk which I believe is seriously underrated: makeresults.

Makeresults (documented here) lets you generate fake events for testing purposes. No indexes are queried, no disks are touched, which means that makes results is very very fast. And when a query runs quickly, that means you can run it more times which means new queries and content will be developed faster.

In this post, I’m going to walk you through a way to use makeresults to learn the difference between the streamstats and eventstats commands.

Continue reading “Using the Makeresults in Command in Splunk”

Back Up Your Google Drive Files with Rclone

Trust, but always make backups.

Google Drive is one of my favorite apps for storing and editing documents and spreadsheets. If don’t currently use Google Drive in place of Microsoft Office, I would recommend checking it out!

That said, while it’s a useful tool, your files are being stored on somebody else’s computer, which means that if your Google account should get hacked or suspended, you will lose access to your files. Not good.

In this post, I will show you how to back up the contents of your Google Drive onto your filesystem. You will need a medium level of knowledge and some experience with the command line for this.

Installing and Configuring Rclone

First, start by downloading Rclone. Rclone is a command line app for managing, copying, and syncing files across over 40 different cloud providers. In addition to Google Drive, it has support for Dropbox, AWS S3, Microsoft OneDrive, and a whole list of cloud providers that I’ve never even heard of!

Once you have Rclone downloaded, start up its configuration wizard by typing:

rclone config
Continue reading “Back Up Your Google Drive Files with Rclone”

Learning Prometheus, Grafana, and Loki with Docker

If you’ve read this blog for any length of time, you’ll know that I’m a big fan of Splunk, and using Splunk to solve everyday problems. But while Splunk excels at being able to eat nearly any kind of event or data, sometimes you need a more specific tool when working with a specific type of data.

That’s where Prometheus, Loki, and Grafana all come in. Prometheus is a time series database built for storing metrics. Loki is a log collection system which scales horizontally and is useful for collecting application logs, and Grafana is the dashboard app which is used to view metrics from either platform!

I wanted to learn more about each of these apps, and I figured the best way to do so was to build out something in Docker that let me ingest data immediately, and then to build some sample dashboards on top of that. I then open sourced it, and the entire project can be found at https://github.com/dmuth/grafana-playground

Getting Started

First, clone the repo and start up all of the Docker containers:

git clone https://github.com/dmuth/grafana-playground.git
cd grafana-playground
docker-compose up -d

This will start up several containers, some of which will ingest data, some of which will store data.

Continue reading “Learning Prometheus, Grafana, and Loki with Docker”

Stupid UNIX Tricks: Find Videos You Posted To Twitter

I’ve seen complaints pop up on Twitter that people are getting their accounts suspended over years old tweets that happen to contain copyrighted music. So let’s say that, like me, you have a Twitter account over 10 years old and you want to go through your old tweets so you can pull any such video before Twitter does — how do you go about doing that?

Well here’s the thing: the UNIX command line is incredibly powerful if you know how to use it. In this post, I’ll show you how to use the bash shell in Linux or Mac OS/X to find those videos so that you can remove them.

“UNIX is basically a simple operating system, but you have to be a genius to understand the simplicity.” — Dennis Ritchie

The first thing you gotta do is download your entire Twitter archive. There are instructions on how to do that here. Once you put in the request, you’ll hear back from Twitter within a day when the download is ready. Expect the file to be rather large — in my case it was over 2 Gigs. Download that file and unzip it.

At the time of this writing, all of your media will be found in the folder data/tweet_media/, so cd into that directory and see how many files there are:

ls -l |wc -l
 10085
Continue reading “Stupid UNIX Tricks: Find Videos You Posted To Twitter”

Getting the Most out of Obsidian

In Part 1, I wrote about how to get your data out of Evernote and into Obsidian. In this post, I’m going to cover how to get the most out of Obsidian in terms of functionality.

Organizing in Obsidian

At a high level, I like to use The PARA Method, which consists of 4 high-level folders for storing your notes. Those folders are:

Projects: Projects are things you are actively researching or working on, such as this blog post. They have deliverables and they have deadlines. Notes should not exist in your project folder forever, but instead be moved into another folder.

Areas of Responsibility: The literal definition that I’ve seen elsewhere is “activity with a standard to be maintained over time”. If you’re using Obsidian for work, it might be for platforms which you own and perform occasional maintenance on, runbooks for dealing with specific issues, etc. If you’re using Obsidian for personal use, it might be for taking notes from books you read, notes about your health, your car, finances, etc.

Resources: A resource is defined as “a topic or theme of ongoing interest”. This might be things like recipes, ideas for home improvement, and the like. I will be the first to admit that sometimes the line blurs between Resources and Areas. The best advice I can offer is to try not to sweat the details here.

Archives: Stuff you’re not using anymore, such as projects you’ve finished or travel plans for trips taken. I recommend ZIPing the folders that hang out in this directory. (Obsidian won’t mind)

Continue reading “Getting the Most out of Obsidian”