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CSS: Set content from other attributes

You can use the content CSS attribute to set an element's content – which is especially useful for the :before and :after pseudo elements:

a:before {
  content: 'Click me: ';
}

The above example would prepend "Click me:" to any link on the page.

Note that you can also refer the contents of other attributes of the element. So, if your links have a helpful title set, you could do this:

a:before {
  content: attr(title) ": ";
}

There also is a jsFiddle for the examp…

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hint.css - A tooltip library in CSS

A tooltip library that does not use Javascript. Works in IE9+.

This library (or the technique used by it) could be a great choice for projects with a lot of tooltips, which are hard to do fast with Javascript.

Useful methods to process tables in Cucumber step definitions

When you accept a table in your Cucumber step definition, that table object will have the cryptic type Cucumber::Ast::Table. Don't immediately call table.raw to convert it into an array of arrays! Cucumber::Ast::Table has a lot of useful methods for tasks such as:

table.raw
Turn the table into an array of arrays
table.hashes
Convert the table to an array of hashes, where the keys are the table headers from the first row

table.headers

git "fatal: bad config file line" after checking out branch

If git gives you an error message such as "fatal: bad config file line 123 in .git/config" after you tried to checkout a branch with a very long branch name, you very likely come across a bug in git version < 1.8.

You should ask someone with a newer git version (someone pushed the branch right?) to rename the branch to something shorter:

git -m old-very-very-long-branch-name new-short-branch-name

Setting expiry dates for images, JavaScript and CSS

When deploying Rails applications you might have noticed that JS and CSS are not cached by all browsers.

In order to force Apache to add expiry dates to its response, add the attached .htaccess to the public directory. This will add a header such as Expires: Thu, 07 Oct 2010 07:21:45 GMT to the httpd response.

Configuring Apache

Check that you have mod_expires enabled. You need it for the attached .htaccess to work:
sudo a2enmod expires

Configuring Nginx

You can add this:
i…

Consul: Dynamically access and query powers for a given name, model class or record

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 …

MySQL: For each group, retrieve a comma-separated list of values in a given column

The technique described in this card has an important caveat: The result of GROUP_CONCAT is truncated to the maximum length that is given by the group_concat_max_len system variable, which has a default value of 1024. This will cause horrible, data-destroying bugs in production. For this reason you should probably not use GROUP_CONCAT ever. At least you must set the value of group_concat_max_len to an insanely high value on every database server your application runs on.


Lik…

High Performance Networking in Google Chrome

About Chrome's network stack and optimizations to load web pages faster.

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What The Rails Security Issue Means For Your Startup

January has been a very bad month for Ruby on Rails developers, with two high-severity security bugs permitting remote code execution found in the framework and a separate-but-related compromise on rubygems.org, a community resource which virtually all Ruby on Rails developers sit downstream of. Many startups use Ruby on Rails. Other startups don’t but, like the Rails community, may one day find themselves asking What Do We Do When Apocalyptically Bad Things Happen On Our Framework of Choice? I thought I’d explain that for the general c…

Migrating IMAP accounts from server to server

Do not investigate in the 2342 tools that exist for migrating IMAP accounts from one server to another. They all suck.

Try your luck with imapsync.
We have no clue why the guys suggest buying the script on their site, maybe they missed removing that part after this April fool's trick.

Go to https://fedorahosted.org/released/imapsync/ and get the sources there.

External content

Amazon Elastic Transcoder

Amazon Elastic Transcoder is video transcoding in the cloud. It is designed to be a highly scalable, easy to use and a cost effective way for developers and businesses to convert (or “transcode”) video files from their source format into versions that will playback on devices like smartphones, tablets and PCs.

This might be a good alternative for services like Panda which charge a large monthly fee just to be available for your encoding requests. Amazon's service bills by usage instead:

A 10 minute sourc…

Memcache: Your cache node may degenerate over time, check your settings

We recently had a problem on a Memcache cluster, where one of the servers showed a significantly worse cache hit rate and a lot more evictions.

It turned out that the only reason was that the server was running for a few months longer than the others. Some investigation showed this to be a known problem with Memcache: Once your cache gets full, it might be "hardwired" for your specific usage patterns. If those change (and you for example start to store larger values), memory is no longer allocated optimally, in extreme cases Memcache might …

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5 reasons why I won't steal your idea

Since I'm a software architect and a web developer, I get often approached by people with their new ideas. In most cases, for some quality feedback, and on lucky days, for a rough quote about the costs of such a project. These people are usually very secretive about what they have, making me explain to them that it's far from my interest to steal that idea. (…) Focus on your product, and don't worry about me stealing your idea. I won't. I have at least five reasons not to.

How to test your website for different Internet Explorer versions?

Virtualization

Microsoft provides images with different IE and Windows combinations for different hosts.
There are also Virtual Box images for Linux hosts.

IETester

IETester is a web browser for Windows which allows you to use different IE rendering and JavaScript engines.

How to express ordinality with numbers in Rails

If you have an integer and want to use it to represent an element's position (like "1st" for 1, or "2nd" for 2), you can use ActiveSupport's ordinalize:

1.ordinalize     # => "1st"
2.ordinalize     # => "2nd"
1002.ordinalize  # => "1002nd"
1003.ordinalize  # => "1003rd"
-11.ordinalize   # => "-11th"
-1001.ordinalize # => "-1001st"

Test that a form field is visible with Cucumber/Capybara

Spreewald now comes with a step that tests if a form field is visible:

Then the "Due date" field should be visible
But the "Author" field should not be visible

The step works by looking up the field for the given label, then checks if that field is hidden via CSS (or Javascript).

It is not currently tested if the label is visible or hidden. For this see: [Check that an element is visible or hidden via CSS with Cucumber/Capybara](https://makandracards.com/makandra/1049-check-that-an-elem…

Consul: Querying a power that might be nil

Consul 0.6.1+ gives your Power class a number of static methods that behave neutrally in case Power.current is nil. This allows you to create authorization-aware models that still work when there is no user at the end of a web browser, e.g. on the console, during tests or during batch processes.


You will often want to access Power.current from another model, to e.g. iterate through the list of accessible users:

class UserReport

  def data
    Power.current.users.c...
External content

Behave.js

Behave.js is a lightweight library for adding IDE style behaviors to plain text areas, making it much more enjoyable to write code in. Features include:

  • Custom Code/Behavior Fencing
  • Hard and Soft Tabs
  • Auto Open/Close Parenthesis, Brackets, Braces, Double and Single Quotes
  • Auto delete a paired character
  • Overwrite a paired character
  • Multi-line Indentation/Unindentation
  • Automatic Indentation
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