When Rails does not recognize Rake tasks in lib/tasks
When you put a Rake task into lib/tasks, but running it fails with...
Don't know how to build task name:of:task
... does your Rake task's filename end in .rb? It needs to end in .rake instead.
Related cards:
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...
PSA: "index: true" in Rails migrations does not work as you'd expect
Several Rails migration methods accept index: true as an option to create an index. In some cases (like #add_column), this option is silently discarded. Know what you are doing, or use #add_index instead.
Example
Consider the following ...
The JavaScript Object Model: A deep dive into 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...
Lightning Talk: Coverage based Test Case Prioritization in Ruby on Rails
For my computer science bachelor's thesis I programmed and evaluated a CLI Test Case Prioritization (TCP) tool for makandra. It has been written as a Ruby Gem and was tested and evaluated against one Ruby on Rails project....
Caching in Rails < 6.1 may down parts of your application when using public cache control
Proxy caching is a good feature to serve your publicly visible application content faster and reduce load on your servers. It is e.g. available in nginx, but also affects proxies delivered by ISPs.
Unfortunately, there is a little problem in Rail...
Rails logs are not flushed automatically (in Rake tasks)
The Rails logger will store its content in a buffer and write it into the file system every 1000 lines. This will come back to bite you when using Rails.logger.info to write log output during Rake tasks or on a production console.
You often won...
How to make changes to a Ruby gem (as a Rails developer)
At makandra, we've built a few gems over the years. Some of these are quite popular: spreewald (> 1M downloads), active_type (> 1M downloads), and geordi (> 200k downloads)
Developing a Ruby gem is different from developing Rails applications, w...
Differences between transactions and locking
Web applications can be used by multiple users at the same time. A typical application server like Passenger has multiple worker processes for a single app. In a distributed deployment setup like we use at makandra you w...
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...
How to negate scope conditions in Rails
Sometimes you want to find the inverse of an ActiveRecord scope. Depending on what you want to achieve, this is quite easy with Rails 7, and a bit more complicated with Rails 6 and below, or when the inverse scope may contain NULL values. [1]
[...