Consul 0.6.1+ gives you a way to dynamically access and query powers for a given name, model class or record.
A common use case for this are generic helper methods, e.g. a method to display an "edit" link for any given record
if the user is authorized to change that record:

module CrudHelper

  def edit_record_action(record)
    if current_power.include_record?(:updatable, record)
      link_to 'Edit', [:edit, record]
    end
  end

end

You can find a full list of available dynamic calls bel...

validates_uniqueness_of is not sufficient to ensure the uniqueness of a value. The reason for this is that in production, multiple worker processes can cause race conditions:

1. Two concurrent requests try to create a user with the same name (and we want user names to be unique)
2. The requests are accepted on the server by two worker processes who will now process them in parallel
3. Both requests scan the users table and see that the name is available
4. Both requests pass validation and create a user with the seemingly available name...

Calling bundle update (without arguments) updates all your gems at once. Given that many gems don't care about stable APIs, this might break your application in a million ways.

To stay sane, update your gems using the applicable way below:

Projects in active development

Update the entire bundle regularily (e.g. once a week). This ensures that your libraries are up-to-date while it's easy to spot major version bumps which may break the app.

Projects that have not been updated in a while

1. [Update a single gem conservatively](htt...

Geordi now has a script that runs capistrano with all known deploy targets (i.e. staging, production...).

Use with

geordi capistrano deploy:migrations

or

geordi capistrano deploy

The abbrevation geordi cap ... works as well.

Apache HTTP server benchmarking tool (ab) is a nice tool to test performance on sites delivered by HTTP. If the site you're about to test is placed behind a login, follow these steps to successfully use ab on it.

1. Open the site to test in the browser of your choice. Do not login yet.
2. Use developer tools to show all cookies used by the site. (Chrome: Ctrl+Shift+i, open the 'Resources' tab and click on the site below 'Cookies' on the left. Firefox: Right-click on the site, open 'We...

If you say git stash, your stashed changes will be identified with an automatically generated message:

$ git stash
Saved working directory and index state WIP on master: 77af0df Merge branch 'production'

While this is okay to temporarily stash away stuff, you may want a better identifier for your changes so you can find them more easily if you stash often.
Of course, there is a way to do it with git:

$ git stash save doing crazy things
Saved working directory and index state On master: doing crazy things

Note that you n...

When calling a scope like current_power.user?(user), Consul will no longer trigger a query if the users power selects all records (SELECT * from users). This should make such checks much faster for users who can access many records, like admins.

You can now define multiple powers at once:

power :users, :updatable_users, :creatable_users do
  ...
end

Example input:

li.active a:link

Example output (specificity):

| 0 | 2 | 2 |

See also: https://www.codecaptain.io/tools/css-specificity-calculator

Axlsx is an incredible gem to generate "Office Open XML" spreadsheet files (XLSX). Does not break on large spreadsheets and supports a ton of features like graphs.

API looks mature and existing code is easy to migrate when coming from the spreadsheet gem.
The documentation of some methods is a bit out of date, but you'll find your way around the gem's code.

No support for reading files, however. :( If you want to open XLSX spreadsheets (for example to confirm your output in tests), you can use [roo](h...

jquery-timing is a very useful jquery plugin that helps to remove lots of nested anonymous functions. It's API provides you some methods that help you to write readable and understandable method chains. See yourself:

Example

// before
$('.some').show().children().doThat();
window.setTimeout(function(){
  $('some').children().doSomething().hide(function() {
    window.setTimeout(function() {
      otherStuffToDo();
    }, 1000);
  });
}, 500);

// after
$('.some').s...

The bash offers control over the behavior of autocompletion.

The most primitive example is this (just run it in your bash; if you want it available everywhere, put the complete ... line into your .bashrc):

> complete -W "list of all words for an automatic completion" command_to_be_completed
> command_to_be_completed a<TAB>
all an automatic

With complete you define how the specified command shall be completed. For basic needs, -W (as in "word list") should be enough, but you may also specify a function, a glob patte...

When searching for text in a MySQL table, you have two choices:

• The LIKE operator
• FULLTEXT indexes (which currently only work on MyISAM tables, but will one day work on InnoDB tables. The workaround right now is to extract your search text to a separate MyISAM table, so your main table can remain InnoDB.)

I always wondered how those two methods would scale as the number of records incr...

If - for whatever reason - you have to render stylesheets dynamically, the following snippet might be of help. It emulates what "sprockets" would to when precompiling your assets, and give your stylesheets access to all the regular bells and whistles (like asset_path, proper @imports etc):

class DynamicStylesheetsController < ApplicationController

    def show
      logical_path = RELATIVE_PATH_TO_YOUR_TEMPLATE
      path = File.join(Rails.root, logical_path)
      template = Sass::Rails::SassTemplate.new(path)
      environment = ...

Our old solution for cronjobs, the "craken" plugin, is no longer maintained and does not work on Rails 3.2+.

We will instead use the whenever gem.

"Whenever" works just like "craken", by putting your rake tasks into the server's cron table. Everything seems to work just like we need it.

Installation for new projects

1. Add "whenever" to your Gemfile:

    group :deploy do
      gem 'whenever', require: false
    end
   

2. Add it to your config/deploy.rb:
   ...

For two years we've been using SearchableTrait which gives models the ability to process Googlesque queries like this:

Contact.search('a mix of words "and phrases" and qualified:fields')

This trait used to be a huge blob of code without tests and documentation, so I made a gem out of it. Check out https://github.com/makandra/dusen for code, tests, and a huge README.

You should use the Dusen gem and delete SearchableTrait in all future projects.

Note that the syntax to define query proc...

If you can now longer hear or record sounds after upgrading Ubuntu, you probably need to re-tell Ubuntu which devices to use for playback/recording.

Fix sound output

• Open the PulseAudio Volume Control (pavucontrol). If you don't have that application, install it with sudo apt-get install pavucontrol.
• Start playback of an MP3 so you can see when changes take effect.
• Under "Output devices" use the "Mute" buttons to figure our which output device is the correct one. When you found it, also set it as the fallback dev...

In Rails 2, when calling instance_eval or instance_exec on a scope, the scope will fetch its records from the database.

This has been fixed in Rails 3+.

A technique to vastly reduce the number of join model records that need to be stored in the database.

The technique is only effective when there is a high redundancy in your data, e.g. combinations of the same 20 tags are used to label thousands of books.

The technique is also limited in that your join models cannot have additional logic, such as attributes or callbacks.

Ther has-many-with-set gem is an implementation of this technique.

Since I use this a lot in my daily work and there were no scripts working properly for me, I made one myself.
It's actually not bound to Xfce but should work on any window manager (haven't tried it, though).

Installation

1. If you don't yet have xdotool, install it:

   sudo apt-get install xdotool
   

2. If you don't yet have wmctrl, install it:

   sudo apt-get install wmctrl
   

3. Store the attached file in some place that's in your PATH.
   The cool kids use ~/bin/.

4. Make it executable: `chmod +x ~/bin/move-to-next-mo...

When you have two models in a has_many, has_one or belongs_to association, the :inverse_of option in Rails tells ActiveRecord that they're two sides of the same association.

Example with a has_many / belongs_to association:

class Forum < ActiveRecord::Base
  has_many :posts, inverse_of: :forum
end

class Post < ActiveRecord::Base
  belongs_to :forum, inverse_of: :posts
end

Knowing the other side of the same association Rails can optimize object loading so forum and forum.posts[0].forum will reference the same o...

JavaScript engines such as Google’s V8 (Chrome, Node) are specifically designed for the fast execution of large JavaScript applications. As you develop, if you care about memory usage and performance, you should be aware of some of what’s going on in your user’s browser’s JavaScript engine behind the scenes.