In order to request a SSL certificate from any dealer, you usually need a CSR certificate. As both the CSR as well as key are created in this step, make sure you save this certificate on a trusted, secure machine only. Usually this is your production environment.

Run this on the server (not on your machine) as root.\
Replace your-domain.tld with the domain you request the certificate for and YYYY with the current year so you will not have any conflicts when requesting a certificate next year.

openssl req -new -sha256 -out www.your-dom...

If you would like to enrich your website with semantic markup like contact data, places or events you should have a look at schema.org. "Search engines including Bing, Google and Yahoo! rely on this markup to improve the display of search results, making it easier for people to find the right web pages."

The following example from the schema.org documentation shows you how to describe a movie with semantic markup:

<div itemscope itemtype ="http://schema.org/Movie">
  <h1 itemp...

If you want to enforce soft tabs (spaces instead of tabstops) in Vim put this into your ~/.vimrc (Linux) or C:\Users\<Username>\_vimrc (Windows):

set tabstop=2
set softtabstop=2
set shiftwidth=2
set expandtab

You can also call those commands in a running Vim instance (using ":set ...") to switch on soft tabs temporarily.

On a side note: remember the :mkvimrc command that saves active settings to a vimrc file.

Put the attached file into config/initializers/ to be able to say created_within on any ActiveRecord or its scope chain. This will return a scope of all records created between two given timestamps.

Use it like that:
Booking.created_within(1.year.ago, Date.yesterday).count
User.active.created_within(1.hour.ago, DateTime.now)

It explicitly looks at the database table name so you are usually fine when joining other tables.

You probably already manage servers you often connect to inside the ~/.ssh/config file. What is nice: you may define alias names for hosts so that you can say something like ssh foobar-staging.

This is especially helpful for servers whose hostnames are hard to remember or who don't have a DNS record at all (and must be accessed via their IP address).

To achieve the above, you can define something like this in your ~/.ssh/config:

Host foobar-staging
  Hostname staging.example.com

Note that SSH will only match this for `ssh f...

When your cucumber features grow massively over time, the test execution can take a lot of time.
One easy way to speed up your test execution is to use the parallel_tests gem.
It comes along with some useful rake tasks that let you setup your local test environment shortly to run your features, specs or unit-tests in parallel.

Follow these steps to get it to work.

1. Add the parallel_tests gem to your Gemfile test sections like that:

   # ./Gemfile
   
   group :development, :test do
   

...

Soon after having written our shell-for script, we wanted to easily get dumps of our productions machines, too. This is how we do it:

dump-for staging [-s]

It will copy the dump to your project's tmp directory and name it according to the capistrano stage you're calling for, here: staging.dump. When you pass the optional -s option, the dump will automatically been sourced into your local development database.

This script ...

After having written useful scripts into makandra notes for a long time, we’ve now tied them into a powerful new gem: geordi.

It gives you the power to

• get a dump from your production database with dump-for production
• install your local gems to the production machine with install-gems-remotely
• execute rake tasks to several environments at the same time with power-rake db:migrate
• and much more

Check it out from github.

Asset pipeline, HTTP streaming, jQuery as default framework, auto-reversable migrations, identity map for ActiveRecord.

Ruby 1.8.x support will be dropped with or after Rails 4.

Sometimes PDF cucumber tests fail at the first test run and succeed at the second run. You can fix this with this step:

When PDF generation is ready
And I follow "Save as PDF"
# Checks for PDF contents go here

Here is the step definition:

When /^PDF generation is ready$/ do
  Then 'I should see ""'
end

Install Ubuntu Server

• Download an image from this site
• Select File > New… to and follow the instructions, choose the .iso file you downloaded as image file
• Deselect "Simple installation" – you want to configure your system yourself
• Start the new virtual machine and follow the instructions

Install VMware Tools

• Choose Virtual Machine > Install VMware Tools from the VMware menu, then:

^
# install required packages
sudo apt-get install build-essential psmisc

# m...

Validations that need to access an associated object may lead to some trouble. Let's exemplify that using this example:

class Project < ActiveRecord::Base
   has_one :note
end

class Note < ActiveRecord::Base
   belongs_to :project
end

Now say we need a validation that ensures that a description is set (validates_presence_of :description) within Note but only if the Project has a flag called external set to true. The following code will lead to some problems as the associated object is not present when creatin...

Occasionally you need to do something directly on the server -- like having all records recalculate something that cannot be done in a migration because it takes a long time.

Let's say you do something like this:

Project.all.each(&:recalculate_statistics!)

Even though you may have been successful with this on your development machine or the staging server, keep in mind that production machines often hold a lot more records. Using all may just work, even with lots of records, but when you iterate over such records and fetch a...

You can seriously speed up deployments with Capistrano when using a local git repository on the server you are deploying to.

Simply add

set :deploy_via, :remote_cache
set :copy_exclude, [ '.git' ]

to your config/deploy.rb and Capistrano will create a clone in shared/cached-copy. This will be updated using git pull when deploying which transfers less bytes and is usually much faster. If deploy_via is set to use default settings (being "export"), Capistrano will do a full clone of the repository from your git host otherwi...

When storing floating-point numbers such as prices or totals in an SQL database, always use a DECIMAL column. Never use FLOAT or kittens will die.

DECIMAL columns are parametrized with a precision and a scale. These parameters describe which numbers can be stored in that column. E.g. a decimal with a precision of 5 and a scale of 2 can store numbers from -999.99 to 999.99, but not 1000 or 1.234.

This card explains what various databases do when you try to store a number in a DECIMAL field, and that number exceeds that colum...

If you save a non-standard object (not a String or Fixnum, etc) like the AwesomeClass from your application in the session of visitors be prepared that some time you will get this exception:

ActionController::SessionRestoreError: Session contains objects whose class definition isn't available. Remember to require the classes for all objects kept in the session. (Original exception: ...)

This happens when you remove your AwesomeClass but users come back to your site and still have the serialization of such objects in their session....

The Edge Rider gem will define a method collect_ids on your ActiveRecord models, scopes, integer scalars and collections, which will return a list of their IDs:

User.last.collect_ids # => [9]
[User.first, User.last].collect_ids # => [1, 9]
User.active.collect_ids # => [4, 5, 6]
[4, 5, 6].collect_ids # => [4, 5, 6]
7.collect_ids #=> [7]

This allows you to parametrize scopes with a variety of argument types:

class Note < ActiveRecord::Base
  named_scope :for_users, lamb...

ActiveRecord gives you the :include option to load records and their associations in a fixed number of queries. This is called preloading or eager loading associations. By preloading associations you can prevent the n+1 query problem that slows down a many index view.

You might have noticed that using :include randomly seems to do one of the following:

1. Execute one query per involved table with a condit...

Rails 3

User.active.to_sql

Rails 2

Use either the Edge Rider or fake_arel gem to get #to_sql backported to Rails 2.

If you don't want to use a gem for this, you can do this with vanilla Rails 2:

User.active.construct_finder_sql({})

Note: ActiveRecord::Base#becomes has a lot of quirks and inconsistent behavior. You probably want to use ActiveType.cast instead.

ActiveRecord models have with a method becomes(klass) which you can use to cast the record into an instance of its subclasses or superclass. This is useful because some parts of Rails reflect on the class of an instance, e....

Bryan talked about the differences between imperative and declarative scenarios. In my opinion, both styles have benefits and should be used appropriately based on the situation. The majority of examples on rspec's story runner currently on the web, including mine, are of the imperative type. Since the declarative type has many advantages I thought it would be worth while to present some examples and contrast the differences between the two styles.

When using ActionMailer, you can set an array of email addresses as recipients. If this array is generated by e.g. collecting email addresses from the database, it might sometimes be empty.

To prevent ActionMailer to deliver mails to nobody, simply overwrite the deliver! method like this:

# In your mailer.rb
def deliver!(mail = @mail)
  return false if (recipients.nil? || recipients.empty?) && (cc.nil? || cc.empty?) && (bcc.nil? || bcc.empty?)
  super
end