Let the browser choose the protocol

Use protocol independent URLs whenever possible so that the browser will choose the protocol related to the protocol which the page is delivered with.

Example issues

  • When your page is delivered via https and you provide a youtube video only via http the most browsers (e.g. Firefox, Chrome) won't display the video.
  • When you deliver your youtube video via https://youtu.be/jyElDp98HdI your test which checks that the embeded video is rendered in the view will fail because your test server doesn't use https

Solution

Let your lin...

Get Moving With Angular 1.2 Animation and Animate.css

Motion is quickly becoming one of the most important emerging techniques in building a quality user experience on the web. Angular 1.2, currently in release candidate form, provides an overhaul of Angular's animation system and makes it spectacularly easy to bring your interface to life.

International Address Fields in Web Forms :: UXmatters

Advice for address forms that work with address structures from multiple countries.

Enable NewRelic monitoring [for Rails] on specific hosts only

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 ...

A simpler default controller implementation

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...

How to not repeat yourself in Cucumber scenarios

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...

Implementing social media "like" buttons: Everything you never wanted to know

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 ...

RailsPanel chrome extension

Chrome extension that shows all info from your rails log (like parameters, response times, view rendering times, DB requests) inside a chrome panel.

Rails 3/4: How to add routes for specs only

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...

You don't need each, collect or select in Coffeescript

Working with lists in Javascript is painful because the native Array class is so poorly designed.

One way to reduce the pain is to to use Underscore.js's functions like _.each, _.map or _.select, which unfortunately clutters your code with awkward calls to the _ helper.

Fortunately when you use CoffeeScript you don't need any of that. CoffeeScript has a very versatile for keyword that can do anything that each, collect or select can do. Enjoy!

each

f...

PostgreSQL cheat sheet for MySQL lamers

So you're switching to PostgreSQL from MySQL? Here is some help...

General hints on PostgreSQL

  • \? opens the command overview
  • \d lists things: \du lists users, \dt lists tables etc

Command comparison

Description MySQL command PostgreSQL equivalent
Connect to the database mysql -u $USERNAME -p sudo -u postgres psql
Show databases SHOW DATABASES; \l[ist]
Use/Connect to a database named 'some_database' USE some_database; \c some_dat...

Disable text-transforms in Selenium tests

Using text-transform: uppercase - especially on form labels - can cause you serious headaches in Selenium tests. Sometimes the web driver will see the uppercase text, sometimes it won't, and umlauts will be a problem as well.

Simply disable it in tests, by

  • adding a body class for tests

    %body{'data-environment' => Rails.env}
    
  • overriding the transforms

    [data-environment="test"] *
      text-transform: none !important
    

List of Compass Mixins

Since we are migrating from our homegrown mixins.sass and helpers.sass to Compass, here is a list of all the mixins provided by Compass.

Compiling Javascript template functions with the asset pipeline

The asset pipeline (which is actually backed by sprockets) has a nice feature where templates ending in .jst are compiled into Javascript template functions. These templates can be rendered by calling JST['path/to/template'](template: 'variables'):

<!-- templates/hello.jst.ejs -->
<div>Hello, <span><%= name %></span>!</div>

// application.js
//= require templates/hello
$("#hello").html(JST["templates/hello"]({ name: "Sam" }));

Whatever is in the <% ... %> is evaluated in Javascript...

Getting rid of space between inline-block elements

When two elements with display: inline-block are sitting next to each other, whitespace between becomes a space character.

Solutions, in decreasing order of awesomeness:

  1. Don't have whitespace between two elements! See Whitespace Removal in Haml if you're using Haml.
  2. Don't use inline-block. Use floating elements instead (don't forget to clear them!).
  3. Try to compensate for the space with a negative margin. Unfortunately you will never be able to negate ...

Font Awesome: List of Unicode glyphs and HTML entities

A list of FontAwesome icons in the form of copyable Unicode characters or HTML entities.

You might prefer to use FontAwesome by simply typing out these characters instead of using CSS classes. Of course you need to then give the containing element as style:

font-family: FontAwesome

Nested controller routes (Rails 2 and 3)

In order to keep the controllers directory tidy, we recently started to namespace controllers. With the :controller option you can tell Rails which controller to use for a path or resource. For nested resources, Rails will determine the view path from this option, too.

That means the following code in routes.rb

resources :users do
  resource :profile, controller: 'users/profiles' #[1]
end

… makes Rails expect the following directory structure:

app/
  controllers/
    users/
      profiles_controller.rb
    users_control...

Rails: Output helpers for migrations

When you're writing migrations that do more than changing tables (like, modify many records) you may want some output. In Rails > 3.1 you have two methods at hand: announce and say_with_time.

In the migration:

class AddUserToken < ActiveRecord::Migration

  class User < ActiveRecod::Base; end

  def up
    add_column :users, :token, :string
    
    announce "now generating tokens"
    User.find_in_batches do |users|
      say_with_time "For users ##{users.first.id} to ##{users.last.id}" do
        users.each do |user|
        ...

Font sizing with rem - Snook.ca

CSS3 comes with new unit rem. It works like em but it is always relative to the <html> element instead of the parent element.

rem units are supported by all browsers and IE9+.

Git & Mac: Working with Unicode filenames

I had some problems with Git and the file spec/fixtures/ČeskýÁČĎÉĚÍŇÓŘŠŤÚŮÝŽáčďéěíňóřšťúůýž. After pulling the latest commits, it would show that file as untracked, but adding and committing it would throw error: pathspec 'check in unicode fixture file once again' did not match any file(s) known to git.

Solution

Install Git version > 1.8.2 using homebrew and set

git config --global core.precomposeunicode true

Done.

Reason

According to the linked Stackoverflow post ...

... the cause is the different im...

Testing shared traits or modules without repeating yourself

When two classes implement the same behavior (methods, callbacks, etc.), you should extract that behavior into a trait or module. This card describes how to test that extracted behavior without repeating yourself.

Note that the examples below use Modularity traits to extract shared behavior. This is simply because we like to do it that way at makandra. The same techniques apply for modules and overriding self.included.

Example
---...

Render a view from a model in Rails

In Rails 5 you can say:

ApplicationController.render(
  :template => 'users/index',
  :layout => 'my_layout',
  :assigns => { users: @users }
)

If a Request Environment is needed you can set attributes default attributes or initialize a new renderer in an explicit way (e.g. if you want to use users_url in the template):

ApplicationController.renderer.defaults # =>
{
  http_host: 'example.org',
  https:      false,
  ...
}
...

Rails: Disable options of a select field

Simply give the select helper an option :disabled, passing either a single value or an array. You need to specify the option's value, not its text.

= form.select :country, Address.countries_for_select, :include_blank => true, :disabled => ['disabled-value1', 'disabled-value-2']

Also see Cucumber: Check if a select field contains a disabled option on how to test this.

exception_notification 3.0.0+ lets you send errors as HTML e-mails

Exception notifications contain a lot of information: Backtraces, HTTP headers, etc. exception_notification tries its best to format this wall of information using ASCII art, but you can also make it send those notification as simple HTML e-mails that have some simple formatting for clarity, but no images etc. To do so, activate this option:

:email_format => :html

Those HTML notifications are still delivered with a text-only version, so if you are using a console cli...