When you print something from within your .bashrc file you will run into trouble when copying something onto your machine using scp for example.

This is because the output from your .bashrc interferes with scp. The solution is to decide whether the bash shell is started interactively (you start a terminal on your screen) or not (scp).

if [ ! -z "$PS1" ]; then
  # This happens in interactive shells only and does not interfere with scp.
  echo "Learn!"
fi

# Attach a file
#
# Example:
#
#   Company.new.logo = File.new…
#
#   Given the file "…" was attached as logo to the company above
#
#
# Example:
#
#   class Gallery
#     has_many :images, :as => :owner
#   end
#
#   class Image
#     belongs_to :owner, polymorphic: true
#   end
#
#   # so container = Image.new; container.file = File.new… , container.owner = object
#
#   Given the file "…" was attached as Image/file to the company above
#
#
# Example:
#
#   Set updated_at with
#
#     Given … above at "2011-11-11 11:11"
#

This error occurs when you already have a database.yml which defines the database for the cucumber environment instead of test. (Spreewald database.sample.yml has changed)

Fix

Change cucumber to test in your databse.yml

test:    # <---
  adapter: mysql2
  database: spreewald_test
  encoding: utf8
  host: localhost
  username: root
  password: password

Say you have a User with a Carrierwave attribute #avatar:

class User < ActiveRecord::Base
  mount_uploader :avatar, AvatarUploader
end

When whitelisting the avatar field in the controller, you might do this:

params[:user].permit(:avatar)

But you probably want this:

params[:user].permit(:avatar, :avatar_cache, :remove_avatar)

In this example:

• :avatar_cache allows a newly upload image to persist through form roundtrips in the case of validation errors (something that isn't possibl...

When you want to find out the data type of an attribute, you can just use ActiveRecord's columns_hash method.

It returns a hash of column objects that include a type attribute (and more database-related information).

Example:

Contract.columns_hash['id'].type
 => :integer
Contract.columns_hash['active'].type
 => :boolean
Contract.columns_hash['updated_at'].type
 => :datetime

If you get a Quota error with OpenStack, it doesn't have to be what it tell.

For example, I've got this message because the RAM Quota was exceed:

2013-11-11 17:13:25 WARNING nova.compute.api [req-bdasdfas-f5d7-4fcd-bf1b-asdfasdf229e ba2c21dadasdfasdf1d6asdfasdfa0f bfe2db2aasdfasdfb8ea686asdfasdfb] Quota exceeded for bfe2db2aasdfasdfb8ea686asdfasdfb, tried to run 1 instances. Cannot run any more instances of this type.
2013-11-11 17:13:25 INFO nova.api.openstack.wsgi [req-bd003113-f5d7-4fcd-bf1b-asdfasdf229e ba2c21dadasdfasdf1d6asdf...

Sometimes you need to monitor a connection from your machine to a specific, single host or network in order to identify which network hop between your machine and the target causes trouble. You can use the following shell script to easily achieve this kind of monitoring.
If the target host is unable to respond to the specified number of ICMP packets, you will get an eMail together with a mtr to see on which hop the problem occurs.

#!/bin/bash

TARGET=8.8.8.8 # Target host or IP address to be monitored.
MAIL_RECIPIENT=you@exam...

Font Combiner offers a way to tweak and adjust any TTF or OTF font (license permitting), by bringing in font glyphs as vector shapes, providing a completely overhauled font generated to the user's specification with alternative metrics options, alternative hinting types, kerning and spacing options and the facility to make any average free font look great.

Examples are here

One of many useful techniques when your test suite needs to talk to a remote API.

If you need to enable NewRelic monitoring on certain machines within the same Rails environment, a simple solution is to utilize the respective hostnames of you machines.

For example, if you have 8 application servers (e.g. app1.example.com, app2.example.com, ...) and want to enable NewRelic on app1 and app2 only, utilize those steps to do so:

1. Put the attached file into your config directory (config/custom_new_relic_configuration.rb).
2. Specify on which hosts NewRelic should be enabled (see NEWRELIC_HOSTS constant and list ...

Rails has always included a scaffold script that generates a default controller implementation for you. Unfortunately that generated controller is unnecessarily verbose.

When we take over Rails projects from other teams, we often find that controllers are the unloved child, where annoying glue code has been paved over and over again, negotiating between request and model using implicit and convoluted protocols.

We prefer a different approach. We believe that among all the classes in a Rails project, controllers are some of the hardest to...

You're better off using debugger-ruby_core_source:

gem install debugger-ruby_core_source

If you can't do this, try the following.

Here is how to fix the following error when installing the debugger gem fails:

Gem::Installer::ExtensionBuildError: ERROR: Failed to build gem native extension

Note: The following example is for a project using Ruby 1.9.3-p448 -- adjust accordingly for your project.

1. Fetch the source for your Ruby version, if you do not yet have it:

   rvm fetch ruby-1.9.3-p448
   

2. Install t...

It is good programming practice to Don't Repeat Yourself (or DRY). In Ruby on Rails we keep our code DRY by sharing behavior by using inheritance, modules, traits or partials.

When you reuse behavior you want to reuse tests as well. You are probably already reusing examples in unit tests. Unfortunately it is much harder to reuse code when writing integration tests with Cucumber, where you need to...

Geordi 0.16+ supports running selenium tests with project-specific firefox versions.

Just update the gem. It will still default to using the old 5.0.1 firefox. If you want another one, add a file .firefox-version to your project, containing your preferred version.

geordi cucumber will prompt (and guide) you to install the given version. You can delete any old installation sitting in /opt/firefox-for-selenium if you have one.

If you need to test interaction with a remote API, check out the VCR gem as an alternative to Webmock or stubbing hell.

The idea behind VCR is that is performs real HTTP requests and logs the interaction in a .yml file. When you run the test again, requests and responses are stubbed from the log and the test can run offline.

It's a great way to mock network requests to an external service without going through the pain of log...

So you client has asked you to implement a row of buttons to like the URL on Facebook, Twitter and Google+. Here are some things you should know about this.

0. Security considerations

Each "like" button is implemented by including a Javascript on your site. This means you are running fucking remote code on your page. You are giving Facebook, Twitter and Google+ full permission to e. g. copy user cookies. Check with your client if she is cool with that. Also note that if you're site is suggesting security by operating under HTTPS ...

You might not know that Rails disables CSRF protection in tests. This means that if you accidentally forget to send the CSRF token for non-GET requests, your tests will be green even though your application is completely broken (a failed CSRF check usually logs out the user). Rails probably does this because CSRF protection sort of requires Javascript.

You want to enable CSRF protection in Cucumber scenarios that can speak Javascript. To do so, copy the a...

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...

There may be reasons to change the locale of your Postgres cluster. A popular one is your development system's locale being used by default (which may be annoying). Here is how to do that.

Beware: By following the steps below, you will drop and recreate your cluster. You will lose all data (including roles). Instructions below include a procedure for dumping and restoring all cluster data (including roles). While it worked at the time of writing, you should have extra backup strategies for a production database.

1. Find the cluster you...

We sometimes send calender data or tasks using iCalendar (ICS) via eMail as specified in RFC 5545.

Recently, a customer noticed that Outlook automatically moved eMails containing such ICS data to deleted items folder and shows the events as tentative on calendar.
This problem is reported on TechNet, for example.

It ...

In contrast to RSpec's included allow_value matcher, the attached matcher will also work on associations, which makes it ideal for testing assignable_values.

Usage example

describe Unit do

  describe '#building' do
    it 'should only allow buildings that a user has access to' do
      building = build(:building)
      other_building = build(:building)
      unauthorized_building = build(:building)

      power = Power.new(build(:user))

      Power.with_power(power) do
        expect(power).to receive(:buildings).at_least...

Preface: Normally, you would not need this in integrations tests (probably that's why it is so hard to achieve), because it is no actual "integration testing". If you use this step, know what you are doing.

Destroying a record with Capybara is not as easy as calling visit user_path(user, method: :delete), because RackTest's visit can only perform GET requests.

With this step you can destroy a records using either Selenium or RackTest. Ex...