Preview what your markdown would look like on Github. Helpful e.g. when writing or extending a Readme for your gem or projects.

Installation

sudo apt-get install cmake libicu-dev # required for building native extensions
gem install octodown

Know that this will install at least 12 other gems. However, the beautiful output should be worth it.

Usage

octodown README.md

Add gem 'database_cleaner' to your Gemfile. Then:

Cucumber & Rails 3+

# features/support/database_cleaner.rb

DatabaseCleaner.clean_with(:deletion) # clean once, now
DatabaseCleaner.strategy = :transaction
Cucumber::Rails::Database.javascript_strategy = :deletion

Cucumber & Rails 2

The latest available cucumber-rails for Rails 2 automatically uses database_cleaner when cucumber/rails/active_record is required -- but only if transactional fixtures are off. To have database_cleaner work correctly:

1. Add the ...

When a gem author releases a new version to Rubygems, usually a tag with the version number (e.g. v1.2.0) is created an pushed to Github, so everyone can check out or take a look at the source code at this point version release at a later time.

If you'd like to take a look at the Readme of a specific Gem version, you can easily switch to that git tag on Github.

Jonas Nicklas, the author of Carrierwave and Capybara, has released Refile, a gem for handling file uploads in Rails. It handles direct uploads (also direct uploads to Amazon S3) better than Carrierwave.

The story and reasoning behind some of the decisions in Refile, and how it's different from Carrierwave, by the author himself, is a good read before deciding which way you'll go.

Big Caveat: Refile only stores the original image and r...

Make sure you have libcurl3-dev installed:

sudo apt-get install libcurl3-dev
gem install typhoeus

Capybara-screenshot can automatically save screenshots and the HTML for failed Capybara tests in Cucumber, RSpec or Minitest.

Requires Capybara-Webkit, Selenium or poltergeist for making screenshots. Screenshots are saved into $APPLICATION_ROOT/tmp/capybara.

Manually saving a page

Additionally you can trigger the same behavior manually from the test using Capybara::Session#save_and_open_page and [...

Databound provides Javascript a simple API to the Ruby on Rails CRUD.

Tries to expose a full model CRUD as an API. Not sure if this is useful for more refined requirements.

Rails guide that covers PostgreSQL-specific column types and usages for Active Record.

You should especially keep in mind the special datatypes that PostgreSQL offers. \
Types like json and array take away a lot of the pain that you had on MySQL projects.

Example use cases for array are tags or storing foreign keys (instead of a join model). You can even index them.

Chances are you're seeing the warning repeated a lot of times, maybe thousands of times. Here's how to reproduce the issue:

Example 1

# bad code
(Time.current .. Time.current + 1.hour).include?(Time.current)

# Use Range#cover? instead of Range#include? since the former does no typecasting into integers.
(Time.current .. Time.current + 1.hour).cover?(Time.current)

Example 2

# bad code
Post.where(:created_at => min_date.beginning_of_day .. max_date.end_of_day)

# Use 'BETWEEN x AND y'
Post.where(['posts.created_at BETWEEN...

Traveling Ruby is a project which supplies self-contained, "portable" Ruby binaries: Ruby binaries that can run on any Linux distribution and any OS X machine. This allows Ruby app developers to bundle these binaries with their Ruby app, so that they can distribute a single package to end users, without needing end users to first install Ruby or gems.

Option 0: Download from the official page (preferred)

• Open https://googlechromelabs.github.io/chrome-for-testing/
• In Section "Stable" > chromedriver / linux64 > Download ZIP from URL
• Take the chromedriver binary from the ZIP file and put it e.g. into ~/bin.

Chromedriver must be available in your path. You can add ~/bin to your path like this:

echo "export PATH=$PATH:$HOME/bin" >> $HOME/.bash_profile

If you're also using Geordi, disable automatic updating of chromedriver in ~/.config/geordi/global.yml:

a...

Shortener is a Rails Engine Gem that makes it easy to create and interpret shortened URLs on your own domain from within your Rails application. Once installed Shortener will generate, store URLS and “unshorten” shortened URLs for your applications visitors, all whilst collecting basic usage metrics.

Upgrading from Ruby 1.8.7 to 2.1.2 took me an hour for a medium-sized application. It involved hardly any changes except

• removing the occasional monkey patch where I had backported functionality from modern Rubies
• Migrating from require to require_relative where I loaded RSpec factories in Cucumber's env.rb (the Rails application root is no longer in the load path by default)
• replacing the old debugger with byebug
• removing sytem_timer from Gemfile (see [this SO thread](http://stackoverflow.com/questions/7850216/how-to-inst...

For our production servers we use Passenger as a Ruby application server. While it is possible to use Passenger for development as an Apache module, the installation process is not for the faint of heart.

Luckily Passenger also comes as a standalone binary which requires zero configuration.

You can Passenger Standalone as a replacement for Webrick or Thin if you'd like to:

• Use SSL certificates locally
• Get performance behavior that is closer to ...

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...

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
---------...

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

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:

   • Update your Cucumber-related gems as described in Upgrading Cucumber and Capybara, including cucumber_spinner and launchy.

   • If you...

If you have this problem when you update your FreeBSD Ports:

===>>> Launching child to update ruby19-iconv-1.9.3.547,1 to ruby20-iconv-2.0.0.576,1

===>>> All >> ruby19-iconv-1.9.3.547,1 (17/17)

===>>> Currently installed version: ruby19-iconv-1.9.3.547,1
===>>> Port directory: /usr/ports/converters/ruby-iconv

	===>>> This port is marked IGNORE
	===>>> Not needed with Ruby 2.0 or newer


	===>>> If you are sure you can build it, remove the
	       IGNORE line in the Makefile and try again.

===>>> Update for ruby19-iconv-1.9.3.547,1 f...

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 ...

We upgraded a Rails 2 application to Rails 3.2 and Ruby 2.1, changed the mysql adapter from mysql to mysql2, but did not activitate the asset pipeline. Instead we used Sass the old-school way (stylesheets in public/sass/*.sass) and relied on stylesheet_link_tag to activate the Sass compiler.

Now all Sass-generated stylesheets inserted the following text into body:before:

Encoding::CompatibilityError: incompatible character encodings: UTF-8 and ASCII-8BIT

I could get rid of this by removing all generated .css files in `...

Create beautiful Javascript charts with one line of Ruby.

Promising chart library for easily rendering charts with Google Charts.

This seems to not submit your data points to Google.

tl;dr: Use with_index

ActiveRecord's find_each with index

If you do not provide a block to find_each, it will return an Enumerator for chaining with other methods:

Person.find_each.with_index do |person, index|
  person.award_trophy(index + 1)
end

Ruby's map with index

Similarly, you may need an index when using other methods, like map, flat_map, detect (when you need the index for detection), or similar. Here is an example for map:

people...