If validations failed for a record, and you want to find out if a specific validation failed, you can leverage ActiveModel's error objects.
You rarely need this in application code (you usually just want to print error messages), but it can be u...

When localizing model attributes via I18n you may run into errors like this:

I18n::InvalidPluralizationData: translation data { ... } can not be used with :count => 1. key 'one' is missing.

They seem to appear out of the blue and the ...

The way MySQL's FULLTEXT tokenizer splits text into word tokens might not always be what you need. E.g. it splits a word at period characters.

Since the tokenizer has near-zero configuration options (minimum word length and stopwords list), you n...

tl;dr

• Use form models to handle this problem
• Or soften the validation to validates_presence_of :parent

Usually you would validate presence of parent object id, like in this example:

class Parent < ActiveRecord::Base
  has_many ...

While upgrading CarrierWave from version 0.11.x to 3.x, we encountered some very nasty fails. Below are the basic changes you need to perform and some behavior you may eventually run into when upgrading your application. This aims to save you some...

The way Rational#to_s works on Ruby has changed from Ruby 1.9 on. Here is how to get the old behavior back.

You may want this for things where Rationals are being used, like when subtracting Date objects from one another.

What's happening?...

One of the most common production errors are ActionController::MethodNotAllowed errors. They usually happen when someone reloads a form by pressing enter/return in the URL field, or by opening JavaScript links incorrectly.

The attached init...

If you get errors from your development WEBrick that contain unicode salad, you are probably requesting the page via SSL. \
Since WEBrick does not speak SSL, so change the URL in your browser to use http instead of https.

The error looked li...

Usually you add errors to :base in ActiveRecord, in case no appropriate attribute could be used to add the error.

Simple Form...