I don’t like the name unit tests.

Jul 10, 2020

I think it leads to arguing along the lines of hey this isn’t a unit test.

I prefer to focus on three qualities of good automated tests

  • Fast (or non-slow)
  • Sturdy (or non-brittle)
  • Isolated (or non-coupled)

Generating Globally Unique IDs

May 29, 2020

Imagine you are building a system to assign unique numbers to each resource that you manage. You want the IDs to be guaranteed unique i.e. no UUIDs. Since these ids are globally unique, each id can only be given out at most once.

Here is a summary of my solution.

def handle_call(:get_id, _from, %{node_id: node_id, counter: counter} = state) do
  <<id::size(64)>> = <<node_id::10, timestamp()::47, counter::7>>
  {:reply, id, %{state | counter: counter + 1}}

git rebase -i HEAD~25

Oct 11, 2019

Andrew Forward's talk on git rebase -i HEAD~25 at WebCamp Zagreb

WebCamp Zagreb 2019 was great. Here’s areview of my talk on time travel and git rebase.

Thank you to the organizing committee of Web Camp Zagreb, everything was amazing.

The Code I Didn’t Write

July 6, 2019

I enjoy reading job listings. There’s the “what’s trending” angle to see the types of skills that appear to be in bemand. There’s the pyschological angle where we as the reader get a peak at what a company values (or doesn’t value) when it comes to hiring and employees.

Installing Packer For Image Creation

June 19, 2019

After you install Golang, it’s easy to install Packer from source.

mkdir -p ~/src && \
  cd ~/src && \
  git clone https://github.com/hashicorp/packer.git && \
  cd packer && \
  make dev

LiveView Talk at Empex 2019

May 18, 2019

My talk at Empex 2019 is Live(View). Click on Read More to get the links to related articles and GitHub Repos.

Andrew Forward's talk on LiveView at Empex 2019

Connecting to AWS using SAML

May 29, 2019

In this article we will connect to our AWS account using SAML, this will allow us to run AWS CLI commands using the same authentication as you use in the browser.

Once complete, you will be able to run

saml2aws login -a 10xdev

An and then have a (configurable) 12 hour session to from the command line.

Phoenix LiveView Examples

May 29, 2019 (originally posted May 18)

LiveView for Phoenix on Elixir is definitely scratching an itch in the world of rich client apps, without having to go full-on client-side framework. Here’s a list of open source projects, some with online demos and other where you can (easily) run the code locally.

Screenshot Description References
Empex Display Manipulating a SVG graphic for the 2019 Empex NY conference Empex SVG Demo <br> Empex SVG Source

HackerRank Template in Elixir

May 27, 2019

Here’s a template for answering HackerRank in Elixir. This is based on the Two Character question

defmodule Solution do
  def go() do
    num = input(:int)
    text = input(:string)
    IO.puts("INPUTS #{num} and #{text}")

  def input(:string), do: IO.read(:line) |> String.trim()
  def input(:int), do: input(:string) |> String.to_integer()

# Now run your code

Now go forth and HackerRank!!!

Getting Started With ChefDK

May 22, 2019

I am getting back into Chef, and the landscape seems to have changed quite a bit in the last 10 years. I am going to documenting the journey in a series of bite sized articles.

Official install docs are here. So follow them, and read along.

LiveView storing Session Data on Redirect

May 21, 2019

How can you have your LiveView login form update the user’s session across pages?

Adding authenticated user to flash

Run Custom JS on LivePage Reload

May 20, 2019

In your LiveView LEEX, you can add a script tag and append a @tick to the id. This will force for the MorphDOM differ to always re-render (aka re-run) that code on the client.

Create a script with tick ID

Falco “From 0% to 100% tested code”

May 15, 2019

Highlights of Llewellyn Falco - From 0% to Cleanly Refactored 100% tested code

Gives you some legacy code to practice.

The video goes through the Gilded Rose Kata to add the following feature.

Continuous Testing with Elixir

Dec 2, 2015

There is great power in having your tests always run, all the time when writing code, it stops the minor interruptions.

$ mix test.watch

Running tests...
Finished in 0.04 seconds (0.04s on load, 0.00s on tests)
104 tests, 0 failures
Randomized with seed 386800

Simple encryption in Elixir

October 24, 2015

Of course you don’t know anyone that actually stores user passwords in plaintext, or database passwords directly in a repository, so this is more for those theoretical developers to provide them with just a little bit more security; without adding much more complexity.

# Encrypt a password and store it in pwd
iex> pwd = Safetybox.encrypt("helloworld")

# Later on, you can validate the user provided password
# against the encrypted stored password
# Oopses, not the same
iex> Safetybox.is_decrypted("goodbyeworld", pwd)

# Ok, validated!
iex> Safetybox.is_decrypted("helloworld", pwd)

A simple web crawler in Golang

June 7, 2014

An exploration of the Go language (golang) to build a simple webcrawler, all code is available on Github. This application was written as an exploration of the language and demonstration of the various features of the language; it is not feature complete but should be complex enough to provide some examples of using Go’s various concurrent features, tied together in a simple command line and web interface.