Get the root class of an ActiveRecord STI hierarchy
Use
base_class
Show archive.org snapshot
.
This traverses up the hierarchy until it encounters either
- a class inheriting from
ActiveRecord::Base
or - a class inheriting from an abstract class (inheriting from
ActiveRecord::Base
)
Related cards:
The JavaScript Object Model: Prototypes and properties
Speaker today is Henning Koch, Head of Development at makandra.
This talk will be in German with English slides.
Introduction
As web developers we work with JavaScript every day, even when our backend code uses anothe...
The Ruby Object Model
In Ruby (almost) everything is an Object
. While this enables a lot of powerful features, this concept might be confusing for developers who have been programming in more static languages, such as Java or C#. This card should help understanding t...
The many gotchas of Ruby class variables
TLDR: Ruby class variables (@@foo
) are dangerous in many ways. You should avoid them at all cost. See bottom of this card for alternatives.
Class variables are shared between a class hierarchy
---------------------------------------------------...
How to create giant memory leaks in AngularJS (and other client-side JavaScript)
This guide shows how to create an AngularJS application that consumes more and more memory until, eventually, the browser process crashes on your users.
Although this guide has been written for Angular 1 originally, most of the advice is relevant...
Fixing "A copy of Klass has been removed from the module tree but is still active"
This can happen during development when classes without automatic reloading are pointing to classes with automatic reloading. E.g. some class in lib
is calling Model.static_method
.
Workaround A
Stop referencing autoloaded classes fro...
Get Moving With Angular 1.2 Animation and Animate.css
Motion is quickly becoming one of the most important emerging techniques in building a quality user experience on the web. Angular 1.2, currently in release candidate form, provides an overhaul of Angular's animation system and makes it spectacu...
CSS: Matching against attributes and their values (or parts of them)
You probably know that you can use CSS selectors to match against elements and their attributes, such as:
a[title] { /* any <a> that has a "title" */ }
a[data-fancy="true"] { /* any <a> that has their "data-fancy" attribute set to "true" *...
Get all associations of an ActiveRecord class
YourClass.reflect_on_all_associations.map(&:name)
Get the class name by calling class_name
, or the type of the association (belongs_to, has_many,...) by calling macro
What collapsing margins are, how they work and when margins do not collapse
Imagine you have 2 HTML boxes. The first one has a margin-bottom
of let's say 30px
and the second one a margin-top
of 20px
. After rules of collapsing margins have been applied we ha...
Rails: Rest API post-mortem analysis
This is a personal post-mortem analysis of a project that was mainly build to provide a REST API to mobile clients.
For the API backend we used the following components:
- Active Model Serializer (AMS) to serializer our Active Record models to J...