Travis changed their default distribution from Ubuntu 14.04 (trusty) to 16.04 (precise). This might break your test setup for new builds.

You can solve this issue by freezing your test distribution in the .travis.yml to Ubuntu 14.04 until you have the time to solve all the issues you will have in 16.04:

dist: trusty

Error details

Here are few indicators that you ran into this issue:

Connection to the PostgreSQL database does not work anymore

Your travis-ci builds might have started failing on the usual

psql -c...

When installing a gem you can use version comparators like >= or ~>. That way it is possible to fetch the latest version of Bundler 1 with this command:

gem install bundler -v '~>1'

How to install bundler for Ruby < 2.3 is a common usecase where you might need Bundler 1.

Cucumber up to version 2 had a neat feature called Step Argument Transforms which was dropped in favor of Cucumber 3 ParameterTypes. While I strongly encourage you to drop your legacy Transforms when upgrading to Cucumber 3, it might not always be possible due to their different design.
This is a guide on how to keep the exact same functionality of your old Transforms while writing them in the style of new `Paramet...

Until Capybara 2, node finders that accept a text option were able to find nodes based on rendered text, even if it spans over multiple elements in the HTML. Imagine a page that includes this HTML:

<div class='haystack'>
  Hi!
  <br>
  Try to match me.
</div>

Even though the text is separated by a <br> tag in the HTML, it is matched until Capybara 2 which used to "squish" text prior to the comparison.

# Capyabara 1 or 2
page.find(...

To keep JavaScript sources small, it can sometimes make sense to split your webpack bundles. For example, if your website uses some large JavaScript library – say TinyMCE – which is only required on some selected pages, it makes sense to only load that library when necessary.

In modern webpack this is easily doable by using the asynchronous import function.

Say we have an unpoly compiler that sets up TinyMCE like this (code is somewhat simplified):

// TinyMCE as part of the main bundle!

import tinymce from 'tinymce/tinymce'

// U...

We're always striving towards keeping our website's JavaScript as small as possible.

If you're using webpack(er), you can use the webpack-bundle-analyzer plugin to get a good overview, which of your JavaScript modules take up how much space, and where you can optimize.

To use it, add it via npm or yarn

yarn add webpack-bundle-analyzer

Then add this to your environment.js:

// Uncomment this code to show statistics of bundle sizes. Generated file will automatically...

Tod is a gem for working with daytimes.

Another additional gem?

Thus SQL has a time datatype for storing time of day in the format hh:mm:ss, neither Ruby nor Rails themselves offer an elegant way to deal with day times.

Time and DateTime both handle daytime values AND calendar date, using them to only store the time of day will end in inconsistent and thus confusing data, e. g. Time.new will initialize with the current Time in your Timezone, DateTime.new initializes at January 1, at an undefined year, without a timezone o...

This is a short overview of things that are required to upgrade a project from the Asset Pipeline to Webpacker. Expect this upgrade to take a few days even the diff is quite small afterwards.

Preparations

1. Find all libraries that are bundled with the asset pipeline. You can check the application.js and the application.css for require and import statements. The source of a library is most often a gem or a vendor directory.
2. Find an working example for each library in the application and write it down.
3. Find out the ver...

Many mail clients do not support external style sheets. Some even require all styling inline, which means you'll have to do your styling inline. For Rails applications, you can use Roadie or premailer, which lets you keep your well-structured CSS files and do the inlining for you.

See Designing HTML email

Since Roadie is now in passive maintenance mode, we go with premailer:

Include premailer in your Gemfile:

gem 'premailer-ra...

While deploying an Ruby update to an old application these days, we encountered the following misleading error:

*** [err :: some-host.makandra.de] You are trying to install in deployment mode after changing
*** [err :: some-host.makandra.de] your Gemfile. Run `bundle install` elsewhere and add the
*** [err :: some-host.makandra.de] updated Gemfile.lock to version control.
*** [err :: some-host.makandra.de] 
*** [err :: some-host.makandra.de] You have deleted from the Gemfile:
*** [err :: some-host.makandra.de] *

We found out a newe...

When we want to use our own (or bought) fonts in an application with Webpack(er), we have two options. We can

• put the fonts directly into your Webpack's assets folder or
• write an npm package with an own sass file that can be imported from the Webpack manifest.

Load fonts from your assets folder

The first option turns out to be straightforward: Import the stylesheets in the index.js of the pack you're using:

// webpack_source_path/application/index.js

import './stylesheets/reset'
import...

Webpacker is Rails' way of integrating Webpack, and version 4 has been released just a few days ago, allowing us to use Webpack 4.

I successfully upgraded an existing real-world Webpack 3 application. Below are notes on everything that I encountered.
Note that we prefer not using the Rails asset pipeline at all and serving all assets through Webpack for the sake of consistency.

Preparations

• Remove version locks in Gemfile for webpacker
• Remove version locks in package.json for webpack and webpack-dev-server
• Install by ca...

We forked trusty memoizer to make two changes:

1. Memoized methods now preserve their arity. Previously all memoized methods had an arity of -1.
2. Memoized methods are now faster at runtime. This will only be noticable if you call a memoized methods many times in the same request.

We published our fork as a new gem named memoized.

memoized is API-compatible to memoizer, you just need to include Memoized instead of `M...

Bundler 2 requires at least Ruby 2.3.0 and RubyGems 2.5.0. You might get the following error when you try to install bundler for Ruby < 2.3:

ERROR:  Error installing bundler:
	bundler requires Ruby version >= 2.3.0.

To fix this error upgrade your project's ruby version or install the last supported version of Bundler for Ruby < 2.3:

gem install bundler -v '~>1'

You will also see an error if your [RubyGems versi...

Summary

• We want to move away from jQuery in future projects
• Motivations are performance, bundle size and general trends for the web platform.
• The native DOM API is much nicer than it used to be, and we can polyfill the missing pieces
• Unpoly 0.60.0 works with or without jQuery

Is jQuery slow?

From: Sven
To: unpoly@googlegroups.com
Subject: performance on smartphones and tablets

Hello

I just used your framework in one project and must say,
I am really pleased with it -- but only on a desktop computer.

Have you benchm...

I had this error:

> gem install bundler
Successfully installed bundler-2.0.1
1 gem installed

> bundle install
Traceback (most recent call last):
	2: from /home/henning/.rbenv/versions/2.5.1/bin/bundle:23:in `<main>'
	1: from /home/henning/.rbenv/versions/2.5.1/lib/ruby/2.5.0/rubygems.rb:308:in `activate_bin_path'
/home/henning/.rbenv/versions/2.5.1/lib/ruby/2.5.0/rubygems.rb:289:in `find_spec_for_exe': can't find gem bundler (>= 0.a) with executable bundle (Gem::GemNotFoundException)

The cause was that Bundler 2 requires RubyG...

When building an application that sends e-mails to users, you want to avoid those e-mails from being classified as spam. Most obvious scoring issues will not be relevant to you because you are not a spammer.

However, your application must do one thing by itself: When sending HTML e-mails, you should include a plain-text body or tools like SpamAssassin will apply a significant score penalty. Here is how to do that automatically.

1. Add premailer-rails to your Gemfile and bundle.
2. Done! ...

If your app does not need to support IE11, you can use most ES6 features without a build step. Just deliver your plain JavaScript without transpilation through Babel or TypeScript, and modern browsers will run them natively.

Features supported by all modern browsers include:

• fat arrow functions (() => { expr })
• let / const
• class
• async / await
• Promises
• Generators
• Symbols
• Rest arguments (...args)
• Destructuring

You won't be able to use import and export, or use npm modules.

See this [ES6 compatibility mat...

In ruby you can easily read and write CSVs with the standard CSV library class.

On top of this, you can use the gem smarter_csv for reading (not writing) CSVs in a more comfortable way:

• Keep in mind, that the development of this gem is in an unknown state and the 2.0 release seems to happen never
• The API will change completely for 2.0, so you might find a bunch of unrelated documentation for 1.2

Here is an example...

Cucumber has an output format that prints step definitions only. You can use this to find unused ones:

1. Temporarily add require_relative 'env' to the top of the first file in features/support. --dry-run makes Cucumber skip loading env.rb.
2. Open a really wide terminal window.
3. bundle exec cucumber --dry-run --format stepdefs | grep -B1 'NOT MATCHED' --no-group-separator | grep features/step_definitions

This will print all unused step definitions from your project – however, the result will include false positives. Step...

When upgrading Rails versions -- especially major versions -- you will run into a lot of unique issues, depending on the exact version, and depending on your app.

However, it is still possible to give some generic advice on how you want to tackle the update in principle.

If you are not really confident about upgrading Rails, have a look at Rails LTS.

How many update steps?

Besides the Rails upgrade itself, you might also want to upgrade your other gems and upgrade your Ruby version.
First decide in how many st...

The exception_notification gem supports to provide custom data to e.g. the fail mail within foreground or background jobs.

ExceptionNotifier.notify_exception(_ex_, :data => {:message => "was doing something wrong"})

Still this can be blocked if you have an initializer where you override the default sections and background_sections option. So remember to add the data option to the desired section if required. In case you raise an exception without a data object, the fail...