Cleaning up: ActiveRecord::Dirty 5.2 API Changes

With the release of Rails 5.2 just around the corner (Rails 5.2 RC1 is already available!), we will be taking a look at some of the upcoming changes to the ActiveRecord::Dirty module. If you're running Rails 5.1, you may have already seen some of the deprecation warnings related to the API changes contained in it. Most of them are behavior changes, and there are some new additions as well.

To better understand these modifications, we'll take a look at sample projects in Rails 5.1 and Rails 5.2.

Read more »

Upgrade Rails from 3.2 to 4.0

This article is part of our Upgrade Rails series. To see more of them, click here.

A previous post covered some general tips to take into account for this migration. This article will try to go a bit more in depth. We will first go from 3.2 to 4.0, then to 4.1 and finally to 4.2. Depending on the complexity of your app, a Rails upgrade can take anywhere from one week for a single developer, to a few months for two developers.

Read more »

AWS S3 Policies for Carrierwave

When you create IAM credentials and policies for your app, you should make sure that they have access to the resources that they need and not more than that!.

This way, if anyone gets access to those credentials, the impact of this leak is reduced to the resources associated with them (and not all the buckets in your S3 account)

Read more »

'Flaky' tests: a short story

One of the hardest failing tests to debug are those which fail randomly, also known as "flaky" tests. You write your test cases, you run the tests in your environment (in random order), and see them all pass. Afterwards, you push your code, your CI server runs them and one test fails.

This is not an uncommon scenario, and one too common when using integration tests which use JS, with Capybara-Webkit or Selenium. But if your failing test doesn't communicate with an external API, doesn't use JS, and passes locally, it can be a bit nerve-wracking.

After you have identified the failing test, and it still passes after running it locally, one way to figure out why it's failing is running its context multiple times.

To automate this process a bit, I like to use the following command:

Read more »

How to run multiple dependent builds on Circle CI

We all know the importance of having a CI tool integrated in your project. It allows you to run your entire test suite every time you want to merge a set of changes. If you have a core project and many projects that depend on it, you want to run the tests for the core project and the dependent projects at the same time. This article explains how you can do it with Circle CI.

Read more »