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Prevent MediaWiki showing PHP version with new extension: ControlSpecialVersion

By Greg Sabino Mullane
October 29, 2014

Sok Kwu Wan

I recently created a new MediaWiki extension named ControlSpecialVersion whose purpose is to allow some control over what is shown on MediaWiki’s “special” page Special:Version. The latest version of this extension can be downloaded from Mediawiki.org. The primary purpose of the module is to prevent showing the PHP and database versions to the public.

As with most MediaWiki extensions, installation is easy: download the tarball, unzip it into your extensions directory, and add this line to your LocalSettings.php file:

require_once( "$IP/extensions/ControlSpecialVersion/ControlSpecialVersion.php" );

By default, the extension removes the PHP version information from the page. It also changes the PostgreSQL reported version from its revision to simply the major version, and changes the name from the terrible-but-official “PostgreSQL” to the widely-accepted “Postgres”. Here is what the Software section of bucardo.org looks like before and after the extension is used:

Note that we are also eliding the git revision information (sha and date). You can also do things such as hide the revision information from the extension list, remove the versions entirely, or even …

Another Round of Tidbits: Browser Tools, Performance, UI

By Steph Skardal
October 20, 2014

It’s been a while since I shared a blog article where I share End Point tidbits, or bits of information passed around the End Point team that don’t necessarily merit a single blog post, but are worth mentioning and archiving. Here are some notes shared since that last post that I’ve been collecting:

• Skeuocard and creditcard.js are intuitive user interface (JS, CSS) plugins for credit card form inputs (card number, security code, billing name).

Skeuocard Screenshot

• StackExchange UX is a Stack Overflow resource for user interface Q&A.
• wpgrep is an available tool for grepping through WordPress databases.
• Here is a nifty little tool that analyzes GitHub commits to report on language convention, e.g. space vs. tab indentation & spacing in argument definitions.

Example comparison of single vs. double quote convention in JavaScript.

• Ag (The Silver Searcher) is a document searching tool similar to ack, with improved speed. There’s also a Ag plugin for vim.
• GitHub released Atom earlier this year. Atom is a desktop application text editor; features include Node.js support, modular design, and a full feature list to compete with existing text editors.
• SpeedCurve is a web …

Updating Firefox and the Black Screen

By Jeff Boes
October 16, 2014

If you are updating your Firefox installation for Windows and you get a puzzling black screen of doom, here’s a handy tip: disable graphics acceleration.

The symptoms here are that after you upgrade Firefox to version 33, the browser will launch into a black screen, possibly with a black dialog box (it’s asking if you want to choose Firefox to be your default browser). Close this as you won’t be able to do much with it.

Launch Firefox by holding down the SHIFT key and clicking on the Firefox icon. It will ask if you want to reset Firefox (Nope!) or launch in Safe mode (Yes).

Once you get to that point, click the “Open menu” icon (three horizonal bars, probably at the far right of your toolbar). Choose “Preferences”, “Advanced”, and uncheck “Use hardware acceleration when available”.

Close Firefox, relaunch as normal, and you should be AOK. You can try re-enabling graphics acceleration if and when your graphics driver is updated.

Reference: here.

Postgres copy schema with pg_dump

By Greg Sabino Mullane
October 9, 2014

Manny Calavera (animated by Lua!)
Image by Kitt Walker

Someone on the #postgresql IRC channel was asking how to make a copy of a schema; presented here are a few solutions and some wrinkles I found along the way. The goal is to create a new schema based on an existing one, in which everything is an exact copy. For all of the examples, ‘alpha’ is the existing, data-filled schema, and ‘beta’ is the newly created one. It should be noted that creating a copy of an entire database (with all of its schemas) is very easy: CREATE DATABASE betadb TEMPLATE alphadb;

The first approach for copying a schema is the “clone_schema” plpgsql function written by Emanuel Calvo. Go check it out, it’s short. Basically, it gets a list of tables from the information_schema and then runs CREATE TABLE statements of the format CREATE TABLE beta.foo (LIKE alpha.foo INCLUDING CONSTRAINTS INCLUDING INDEXES INCLUDING DEFAULTS). This is a pretty good approach, but it does leave out many types of objects, such as functions, domains, FDWs, etc. as well as having a minor sequence problem. It’s also slow to copy the data, as it creates all of the indexes before populating the table via INSERT.

My preferred approach …

Liquid Galaxy at the Ryder Cup 2014

By Will Plaut
October 6, 2014

End Point was proud to present the Liquid Galaxy for the French Golf Federation at this year’s Ryder Cup in Gleneagles, Scotland. The French Golf Federation will be hosting the cup in 2018 at Le Golf National, which is just outside of Paris and is also the current venue of the French Open.

Throughout the event, thousands of people came in and tried out the Liquid Galaxy. The platform displayed one of its many hidden talents and allowed golf fans from around the world to find and show off their home courses. One of the most interesting things to witness was watching golf course designers accurately guess the date of the satellite imagery based on which course changes were present.

This deployment presented special challenges: a remote location (the bustling tented village adjacent to the course) with a combination of available hardware from our European partners and a shipment from our Tennessee office. Despite these challenges, we assembled the system, negotiated the required network connectivity, deployed the custom interface, and delivered a great display for our sponsoring partners. The event was a great success and all enjoyed the unseasonably mild Scottish weather.

Rails Recursive Sorting for Multilevel Nested Array of Objects

By Selvakumar Arumugam
October 6, 2014

Whenever you display data as a list of records, sorting them in a particular order is recommended. Most of the time, Rails treats data as an array, an array of objects, or as a nested array of objects (tree). We would like to use a general sorting mechanism to display the records in ascending or descending order, to provide a decent view to end users. Luckily, Rails comes with a sorting method called ‘sort_by’ which helps to sort the array of objects by specific object values.

Simple Array:

Trivially, an array can be sorted just by sorting using the “sort” method:

my_array = [ 'Bob', 'Charlie', 'Alice']

my_array = my_array.sort;  # (or just my_array.sort!)

This is the most basic way to sort elements in an array and is part of Ruby’s built-in API.

Array of Objects:

Usually, the result set of the Rails will have an array of objects and should be sorted based on specific attributes of the object in the array. Here is a sample array of objects which need to be sorted by date and fullname.

s_array =
[  
    {
        "date"=> "2014-05-07",
        "children"=> [],
        "fullname"=> "Steve Yoman" …

Liquid Galaxy at UNC Chapel Hill

By Dave Jenkins
October 3, 2014

End Point has brought another academic Liquid Galaxy online! This new display platform is now on the storied campus of University of North Carolina - Chapel Hill. With a strong background in programming and technology, UNC wanted a premiere interactive platform to showcase the GIS data and other presentations the school researchers are putting together.

Neil Elliott, our hardware manager for Liquid Galaxy, first assembled, preconfigured, and tested the computer stack at our facility in Tennessee, bringing together the head node, display nodes, power control units, switches, and cases to build a “Liquid Galaxy Express”: an entirely self-contained Liquid Galaxy unit that fits in just under 1-meter cubed. From there, Neil drove the computers and custom-built frame directly to Chapel Hill. Our install manager Neil described it as: “It’s a great drive from our office in Tennessee over the mountains to Chapel Hill. When I arrived, the UNC staff was on-hand to help assemble things, lay out the space, and it all went very quickly. We were live by 4pm that same day.”

Overall, the installation took just over 6 hours, including assembly and final configuration. The University’s library …

Parsing Email Addresses in Rails with Mail::Address

By Patrick Lewis
October 3, 2014

I’ve recently discovered the Mail::Address class and have started using it for storing and working with email addresses in Rails applications. Working with an email address as an Address object rather than a String makes it easy to retrieve different parts of the address and I recommend trying it out if you’re dealing with email addresses in your application.

Mail is a Ruby library that handles email generation, parsing, and sending. Rails’ own ActionMailer module is dependent on the Mail gem, so you’ll find that Mail has already been included as part of your Rails application installations and is ready for use without any additional installation or configuration.

The Mail::Address class within the library can be used in Rails applications to provide convenient, object-oriented ways of working with email addresses.

The class documentation provides some of the highlights:

a = Address.new('Patrick Lewis (My email address) <patrick@example.endpoint.com>')
a.format       #=> 'Patrick Lewis <patrick@example.endpoint.com> (My email address)'
a.address      #=> 'patrick@example.endpoint.com
a.display_name #=> 'Patrick …