See this Railscast.

Basically you can simply write views like index.xlsx.erb:

<?xml version="1.0"?>
<Workbook xmlns="urn:schemas-microsoft-com:office:spreadsheet"
  xmlns:o="urn:schemas-microsoft-com:office:office"
  xmlns:x="urn:schemas-microsoft-com:office:excel"
  xmlns:ss="urn:schemas-microsoft-com:office:spreadsheet"
  xmlns:html="http://www.w3.org/TR/REC-html40">
  <Worksheet ss:Name="Sheet1">
    <Table>
      <Row>
        <Cell><Data ss:Type="String">ID</Data></Ce...

At TaskRabbit, we have gone through a few iterations on how we make our app(s). In the beginning, there was the monolithic Rails app in the standard way with 100+ models and their many corresponding controllers and views. Then we moved to several apps with their own logic and often using the big one via API. Our newest project is a single “app” made up of several Rails engines. We have found that this strikes a great balance between the (initial) straightforwardness of the single Rails app and the modularity of the more service-oriented ar...

Lets say we have a user with a contract whereas contract is a mounted carrierwave file.

Now we want to send the link to the contract in a mail. For this use case join the root_url with the public contract path in the mailer view:

Plain text email

URI.join(root_url, @user.contract.url)

HTML email

link_to('Show contract', URI.join(root_url, @user.contract.url).to_s)

Note: You need to follow [http://guides.rubyonrails.org/action_mailer_basics.html#g...

GoodJob is a new background worker gem. It's compatible with ActiveJob.

We're huge fans of Sidekiq for its stability and features. One advantage of GoodJob over Sidekiq is that GoodJob doesn't require Redis. So in cases where you don't have Redis or don't want to pay for a Redis HA quorum node, this might be an alternative worth checking out.

Sometimes you might want to limit the number of associated records in a has_many association, but cannot add a foreign key to the other model (using belongs_to).

There are many takes on limiting the number of associated records in has_many associations, but none feels smooth.

However, when your...

Artifice allows you to replace the Net::HTTP subsystem of Ruby with an equivalent that routes all requests to a Rack application.

You can use Sinatra, raw Rack, or even Rails as your application, allowing you to build up an equivalent to the remote service you are mocking out using familiar and convenient tools to route requests and build up responses.

The migration DSL now supports adding and removing foreign keys. They are dumped to schema.rb as well. At this time, only the mysql, mysql2 and postgresql adapters support foreign keys. @rubyonrails

Workings

add_foreign_key(:comments, :users)

adds a database constraint

ALTER TABLE "comments" ADD CONSTRAINT comments_user_id_fk FOREIGN KEY ("user_id") REFERENCES "user" ("id")

Disadvantage

Foreign key constraints double the validatio...

Did you know?

rake stats # => LOC per controllers, models, helpers; code ratios, and more
rake notes # => collects TODO, FIXME and other Tags from comments and displays them
rake about # (Rails 3+) => Rails, Ruby, Rake, Rack etc. versions, used middlewares, root dir, etc.

If you want to have routes that are only available in tests (e.g. for testing obscure redirects), you can use the with_routing helper -- but that one destroys existing routes which may break a specs that require them to work.

To keep both "regular" and test routes, do this:

class MyApplicationController < ActionController::Base
  def show
    render text: 'Welcome to my application'
  end
end

test_routes = Proc.new do
  get '/my_application' => 'my_application#show'
end
Rails.application.routes.ev...

Ever wondered if there is a reverse for Rails' .each(&:to_s) idiom? Turns out there is...

You probably already know, that you can abbreviate code like

dogs.each { |dog| dog.bark! }

with

dogs.each(&:bark!)

Now suppose it is the other way round and you have

bones.each { |bone| dog.eat!(bone) }

Good old Ruby already has a solution:

bones.each(&dog.method(:eat!))

There is a bug in Rails 3's dbconsole script, which makes the following command open a database console for the development environment:

rails dbconsole -p test

You need to write this instead:

rails dbconsole test -p

Passenger gives you the possibility to define in which environment your app should be started.
This has to be added to the VirtualHost configuration for Apache for Rails 2 applications:

RailsEnv development

When running Rails 3, you need

RackEnv development

Adds missing native PostgreSQL data types to ActiveRecord and convenient querying extensions for ActiveRecord and Arel for Rails 4.x

Common table expressions

• Relation#with
• Model.from_cte

Arrays

Face.where.contains tags: %w[happy smiling] # Matching faces have both 'happy' and 'smiling' tags
Face.where.overlap tags: %w[happy smiling] # Matching faces have at least one of these tags
Face.where.any tags: 'happy' # Matching faces include the 'happy' tag
Face.where.all tags: 'dunno' # Not documented, try for yourself

...

Free Hoptoad/Airbrake alternative which can capture exceptions from any platform. It comes with a Rails notifier and a RESTful API to write your own notifiers for Javascript, etc.

Should we some day wish to do away with the current way we deal with exceptions, this might be a good place to start.

Our new scope-based authorization gem for Ruby on Rails has been released. This might one day replace Aegis as our standard authorization solution.

Adds a slide out panel to your Rails application that directs clients to test stories that have been marked as 'delivered' in Pivotal Tracker.

Wrapper from Globalite API to the Rails 2.2 I18n API

I am a huge fan of SASS (Syntactically Awesome Stylesheets) for styling Rails applications. I have been using it on all of my projects for quite a while now and have developed some great techniques that make it much easier to organize, write, and read stylesheets in an application

Noel Rappin discusses ways to keep up with edge Rails.

A Rails FormBuilder with semantically rich and accessible markup.

Rails’ script/console makes it easy to fetch, view and edit your database records. But can you edit those records as quickly as you edit code in your text editor? Riiight, like editing our database records in an editor is gonna happen? It already has.

Simplifies plugin testing by creating an isolated Rails environment that simulates its usage in a real application

A Rails plugin that delivers a special message to DiggBar users, or runs frame-killer javascript.

Effortless backend interface for Ruby on Rails applications. (Admin scaffold generator.)