PSA: Dont allow private gems to be pushed to rubygems.org

If you make a gem with Bundler, you will get a rake release task that will instantly publish your gem to rubygems.org for all the world to admire. For private gems this is very bad.

To make sure this cannot happen, rubygems 2.2+ allows you to restrict eligible push hosts:

Gem::Specification.new 'my_gem', '1.0' do |s|
  # ...
  s.metadata['allowed_push_host'] = 'https://gems.my-company.example'
end

In case you already messed up, [follow these instructions to get your gem removed](http://help.rubygems.org/kb/rubygems/removing-an-a...

Speed up JSON generation with oj

Using this gem I could get JSON generation from a large, nested Ruby hash down from 200ms to 2ms.

Its behavior differs from the default JSON.dump or to_json behavior in that it serializes Ruby symbols as ":symbol", and that it doesn't like an ActiveSupport::HasWithIndifferentAccess.

There are also some issues if you are on Rails < 4.1 and want it to replace #to_json (but you can always just call Oj.dump explicitely).

Security warning: Oj does not escape HTML entities in JSON
---------...

Downgrade Bundler in RVM

Confusingly, RVM installs the bundler gem into the @global gemset, which is available to all gemsets and Rubies.

You can get around this and install a particular bundler version like this:

rvm @global do gem uninstall bundler
rvm @global do gem install bundler -v 1.6.5

New Firefox and gem versions for our Selenium testing environment (Ubuntu 14.04+)

Firefox 5.0.1, which we were using for most Rails 2.3 projects, does not run on Ubuntu 14.04 any more. Here is how to update affected projects.

  1. Update (or create) .firefox-version with the content: 24.0
    If you haven't installed Firefox 24 yet, the next time you run tests with Geordi, it will tell you how to install it.

  2. On a Rails 2 project:

bower-rails can rewrite your relative asset paths

The asset pipeline changes the paths of CSS files during precompilation. This opens a world of pain when CSS files reference images (like jQuery UI) or fonts (like webfont kits from Font Squirrel), since all those url(images/icon.png) will now point to a broken path.

In the past we have been using the vendor/asset-libs folder ...

Angular-xeditable :: Edit in place for AngularJS

Angular-xeditable is a bundle of AngularJS directives that allows you to create editable elements.

Such technique is also known as click-to-edit or edit-in-place.

It is based on ideas of x-editable but was written from scratch to use power of angular and support complex forms / editable grids.

Wrapping Your API In A Custom Ruby Gem

Nice tutorial about packaging Ruby bindings to your API in a Ruby gem, with tests using VCR casettes.

Use a Bash function to alias the rake command to Spring binstubs or "bundle exec" fallback

There are different ways to run rake:

  • On Rails 4.1+ projects, you have Spring and its binstubs which dramatically improve boot-up time for Rake and similar. You need to run bin/rake to use them.
  • On older projects, you want to run "bundle exec rake" to avoid those ugly "already activated rake x.y.z" errors that hit you when different rake versions are installed for your current Ruby.

Here is a solution that gives you a plain rake command which uses a binstubbed bin/rake if available and falls back to bundle exec rake if necessar...

Using rbenv on Ubuntu 18.04+

We will be installing rbenv and ruby-build from our own fork, not from the Ubuntu sources.

Installing rbenv

  1. Install rbenv:

    git clone https://github.com/rbenv/rbenv.git ~/.rbenv
    

    For Bash:

    echo 'export PATH="$HOME/.rbenv/bin:$PATH"' >> ~/.bashrc
    echo 'eval "$(rbenv init -)"' >> ~/.bashrc
    

    For ZSH:

    echo 'export PATH="$HOME/.rbenv/bin:$PATH"' >> ~/.zshrc
    echo 'eval "$(rbenv init -)"' >> ~/.zshrc
    

    Now reinitialize ...

Ubuntu: Fix "An error occurred while installing pg"

If you get an error like this:

An error occurred while installing pg (0.17.1), and Bundler cannot continue.
Make sure that gem install pg -v '0.17.1' succeeds before bundling.

Then do this:

sudo apt-get install libpq-dev

... and run Bundler again.

What we know about PDFKit

What PDFKit is

  • PDFKit converts a web page to a PDF document. It uses a Webkit engine under the hood.
  • For you as a web developer this means you can keep using the technology you are familar with and don't need to learn LaTeX. All you need is a pretty print-stylesheet.

How to use it from your Rails application

  • You can have PDFKit render a website by simply calling PDFKit.new('http://google.com').to_file('google.pdf'). You can then send the...

Interacting with a Microsoft Exchange server from Ruby

Microsoft Exchange service administrators can enable Exchange Web Services (EWS) which is a rather accessible XML API for interacting with Exchange. This allows you to read and send e-mails, create appointments, invite meeting attendees, track responses, manage to-do tasks, check user availability and all other sorts of things that are usually only accessible from Outlook.

You can implement an EWS by hand-rolling your XML (the [docs](http://msdn.microsoft.com/en-us/...

Feedjira

Great gem to consume RSS feeds. I was missing some features on Ruby's RSS::Parser that I found in Feedjira:

  • Speed
  • Does not break on slightly malformed RSS feeds (like a missing length attribute on an <enclosure> tag on gizmodo.de's feed)
  • It automatically resolves Feedburner-mangled URLs (hooray!)

The GitHub project has only a minimalistic readme. You can find its documentation on their homepage.

gazay/ids_please

Parses URLs of social networks to extract IDs or screen names.

It does not get confused by child routes: you may also pass URLs like a user's twitter photo stream and the gem will extract their twitter ID .

Note that it just parses URLs, and does nothing magic like looking up IDs when the URL contains only a screen name (e.g. the Instagram API requires you to send the user ID almost always while you at first only know their screen name).

Use byebug on Ruby 2+

The debugger gem does not seem to be properly working on Ruby 2. Use byebug instead!

Byebug is a simple to use, feature rich debugger for Ruby 2. It uses the new TracePoint API for execution control and the new Debug Inspector API for call stack navigation, so it doesn't depend on internal core sources. It's developed as a C extension, so it's fast. And it has a full test suite so it's reliable. Note that byebug works only for ruby 2.0.0 or newer. For...

Rails Assets

Automatically builds gems from Bower packages (currently 1700 gems available). Packaged Javascript files are then automatically available in your asset pipeline manifests.

Why we're not using it

At makandra we made a choice to use bower-rails instead. While we believe Rubygems/Bundler to be superior to Javascript package managers, we wanted to use something with enough community momentum behind it that it won't go away in 10 years...

whenever: Make runner commands use bundle exec

In whenever you can schedule Ruby code directly like so:

every 1.day, :at => '4:30 am' do
  runner "MyModel.task_to_run_at_four_thirty_in_the_morning"
end

Combined with the best practice to hide background tasks behind a single static methods you can test, this is probably preferable to defining additional Rake tasks.

Unfortunately when whenever register a runner command, it doesn't use bundle exec in the resulting crontab. This gets you errors like this:

`gem_original_require': no suc...

shoulda-matcher methods not found in Rails 4.1

So you're getting an error message like the following, although your Gemfile lists shoulda-matchers and it has always worked:

NoMethodError:
  undefined method `allow_value' for #<RSpec::ExampleGroups::Person::Age:0x007feb239fa6a8>

This is due to Rails 4.1 (specifically, Spring) revealing a weak point of shoulda-matchers -- jonleighton explains why.

Solution

The solution is to follow [the gem's installation guide](https://github.com/thoughtbot/sh...

3 ways to run Spring (the Rails app preloader) and how to disable it

spring ...

The most obvious way to use spring is to call it explicitly:

spring rails console
spring rake db:migrate

Binstubs

Binstubs are wrapper scripts around executables. In Rails they live inside bin/. If you run spring binstub --all, your binstubs will be using Spring.

bin/rails console
bin/rake db:migrate

bundle exec rails ...

Bundle exec is inconsistent when it comes to spring. Some commands will use it, some won't.

bundle exec rails console # starts Spring...

How to test bundled applications using Aruba and Cucumber

Aruba is an extension to Cucumber that helps integration-testing command line tools.

When your tests involve a Rails test application, your tool's Bundler environment will shadow that of the test application. To fix this, just call unset_bundler_env_vars in a Cucumber Before block.

Previously suggested solution

Put the snippet below into your tool's features/support/env.rb -- now any command run through Aruba (e.g. via #run_simple) will have a clean Bundler envir...

mattheworiordan/capybara-screenshot

Using this gem, whenever a Capybara test in Cucumber, Rspec or Minitest fails, the HTML for the failed page and a screenshot (when using capybara-webkit, Selenium or poltergeist) is saved into $APPLICATION_ROOT/tmp/capybara.

Link via Binärgewitter Podcast (German).

If Guard takes forever to start...

For me guard recently took a very long to start (as in "minutes"), because I had lots of images in public/system.

Upgrading the listen gem (which is a dependency) to 2.7.7 fixed this.

assignable_values 0.11.0 can return *intended* assignable values

As you know, assignable_values does not invalidate a record even when an attribute value becomes unassignable. See this example about songs:

class Song < ActiveRecord::Base
  belongs_to :artist
  belongs_to :record_label

  assignable_values_for :artist do
    record_label.artists
  end
end

We'll create two record labels with one artist each and create a song for one artist. When we change the song's record label, its artist is still valid.

makandra = RecordLabel.create! name: 'makandra records'
dominik...

Things to consider when using Travis CI

Travis CI is a free continuous integration testing service. However, it is really fragile and will break more than it will work.

If you choose to use it anyway, learn the lessons we already learnt:

Use a compatible Rubygems for Rails 2.3 on Ruby 1.8.7

Ruby 1.8.7 is not compatible with current Rubygems versions (> 2.0). Runnig rvm rubygems latest-1.8 --force will fix this and install Rubygems version 1.8.29.

To make Travis CI do this, add `before_script: rvm rubygems latest-1....