DevOps Curriculum

Based on the Ruby Basics Card in the developer Curriculum Ruby is the programming language we use on the backend...

In case you have trouble with the zeitwerk autoloader, you can check out the documentation Autoloading and Reloading Constants and...

Instead of using Puppet exported resources you can use the puppetdb_query feature. This can result in more complex code...

makandra Operations

How can I configure virtual IP's? There are two parameter to set up virtual ips in Keepalived: virtual_ipaddress...

tl;dr Since Rails 6.1+ you can use .compact_blank or .compact_blank! to remove blank values from collections (e.g...

When paginating records, we usually need to know the number of total records in order to render pagination links. Popular...

You can use the code below to check whether the browser can make connections to the current site: await isOnline...

Somewhat regularly, you will need to filter a list down to some items and then map them to another value...

joshmcarthur.com

I recently wanted to add a model for address information but also wanted to add a unique index to those...

blog.saeloun.com

Imagine these models and associations: class Deck < ApplicationRecord has_many :cards end class Card < ApplicationRecord belongs_to :deck, optional: true...

When changing code in mailers, updating the corresponding mailer preview can be forgotten very easily. Mailer previews can be tested...

When redirecting you should take care to use the right HTTP status code. From controllers When redirecting from a controller...

Recent IRB versions include a multi-line autocomplete which may be helpful to novice users but can be distracting.

It might sometimes be useful to check whether your Rails application accesses the file system unnecessarily, for example if your...

Testing file download links in an end-to-end test can be painful, especially with Selenium. The attached download_helpers.rb provides...

makandracards.com

If you get an error message like this: You have already activated some-gem 1.2.3, but your Gemfile requires some...

While verifying doubles in RSpec is a good default, it is limited in the amount of methods it actually is...

I recently had the problem that embedded code boxes crashed my layout. It turned out that pres break out of...

tl;dr With ES2021 you now can use str.replaceAll(), Promise.any(), logical assignment operators, numeric separators and WeakRef on all major...

Code quality can be measured in four levels: (Working code) Reliable code (minimum) Readable code (ok for short-lived code...

DevOps Curriculum

Der Begriff systemd wird immer umfassender da es sich nicht mehr (wie ursprünglich) nur um ein init Systemd handelt, sondern...

DevOps Curriculum

Linux Kernel Parameter werden üblicherweise schon zur Compile und Startzeit mit brauchbaren Default-Werten geliefert. Allerdings muss man, je nach...

makandra dev

You'll need openssl-3 or newer for servers running 22.04 Ruby version 3.1 uses by default the gem openssl...

Unter Linux gibt es mehrere Dateisysteme. Es ist gut einen Überblick zu haben welche existieren und wie man die Dateisysteme...