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To ask or not to ask? Debug first.

By Miguel Alatorre
February 18, 2013

Jumping head first into a project, the ramp up will likely lead to questions galore. In the eagerness of getting things done, it seems like the best thing to do when stuck is to just ask the seasoned developers to tell you how to move forward. After all, they did build the application. However, when to reach out for help can be dependent on the deadline and priority of the task at hand as well as your subjective definition of “stuck.” Knowing when it’s too early, just right, or too late to get help can be a tricky thing. Here are some things to consider when reaching out for help early:

Pros.

 1. Time/money is of the essence and getting a quick answer is best.

 2. Time saved debugging a particular issue that does not further your understanding of the application can be applied elsewhere.

Cons.

 1. You risk a learning opportunity by throwing in the towel too early.

 2. You risk looking lazy or unprepared if the person whom you are reaching out to believes you could have done more.

 3. Developers are busy, too.

All cases being different, there is no right time to reach out for help but steps can be taken to ensure that you have your part. First, get better at reading source code. The …

Configuring RailsAdmin 0.0.5 with CKeditor 3.7.2

By Marina Lohova
February 15, 2013

If you like adventures, read on! Because recently I went trough a really tough one with RailsAdmin 0.0.5 and Ckeditor 3.7.2 in production mode. I only needed to enable the WYSIWYG editor for one of the fields in admin, yet it turned out to be a bit more than just that.

After I installed ckeditor gem, created the custom config file as described in Ckeditor gem readme and added ckeditor support to the field as suggested by RailsAdmin configuration tutorial, both frontend and backend in production mode were broken in pieces with JavaScript errors. So what did I do wrong?

The problem with frontend

After careful investigation it turned out that ckeditor files were not loading on the frontend, but my custom ckeditor configuration file was. And because CKEDITOR was not defined anywhere, the following code in my config.js failed:

CKEDITOR.editorConfig = function( config )
 {
   config.toolbar = 'Basic';
   config.toolbar_Basic =
   [
     ['Source', 'Bold', 'Italic', 'NumberedList', 'BulletedList', 'Link', 'Unlink']
   ];

   config.enterMode = CKEDITOR.ENTER_BR;
   config.shiftEnterMode = CKEDITOR.ENTER_BR; …

Kamelopard Updates

By Josh Tolley
February 15, 2013

I’ve just pushed Kamelopard v0.0.10 to RubyGems. With the last couple of releases, Kamelopard has gained a couple of useful features I felt deserved some additional attention.

Support for viewsyncrelay actions

Many of our Liquid Galaxy tours require more than just Google Earth. For instance, it’s not uncommon to want audio or video media to play at a certain point in the tour. We may want our Liquid Galaxy enabled panoramic image viewer to start up and display an image, or perhaps we need to signal some other external process. Unfortunately Google Earth tours don’t support configuration to run these actions directly upon reaching a certain point, but there are alternatives. Google Earth synchronizes nodes in a Liquid Galaxy with what are called ViewSync packets, which tell all the slave nodes exactly where a master node’s camera is positioned, in terms of latitude, longitude, tilt, etc. We can watch this traffic to determine the master node’s progress through a tour and trigger actions at defined locations, and we use an application called viewsyncrelay (available here) to do exactly that. We configure viewsyncrelay to run certain actions when the ViewSync traffic matches a set of …

Git as rsync

By Jeff Boes
February 14, 2013

I had a quick-and-dirty problem to solve recently:

The clients had uploaded many assorted images to a development camp, but the .gitignore meant those updates were not picked up when we committed and pushed and rolled out to the live site. Normally, one would just rsync the files, but for various reasons this was not practical.

So my solution, which I think can get filed under “Stupid ‘git’ tricks (as opposed to Tricks of a Stupid Git)”:

(on the source repo)

$ git checkout -b images_update
$ git add -f path-to-missing-images
$ git commit -m 'Do not push me! I'm just a silly temporary commit'

(“add -f” forces the images into the index, overriding our gitignore settings)

(on the target repo)

$ git remote add images /path/to/source/repo
$ git fetch
$ git checkout -f images/images_update path-to-missing-images
$ git remote rm images
$ git reset HEAD path-to-missing-images

That last “git reset” is because the newly-restored images will be git-added by default, and we didn’t want them committed to the central repo.

So what did we do here? For those dumbfounded by the level of silly, we used git to record the state of all the files in a certain path; then we pulled them back …

Detecting Bufferbloat

By Brian Buchalter
February 11, 2013

Bufferbloat is topic which has been gaining broader attention, but is still not widely understood. This post will walk you through the basics of bufferbloat and how to determine if you are the victim of bufferbloat.

A Brief Synopsis of the Bufferbloat Problem

The topic of bufferbloat has been explained wide and far, but I’ll add to the conversation too, focusing on brevity. This summary is based on the highly informative and technical talk Bufferbloat: Dark Buffers in the Internet, a Google Tech Talk by Jim Gettys. There is an assumption in the design of TCP that if there is network congestion, there will be timely packet loss. This packet loss triggers well designed TCP flow control mechanisms which can manage the congestion. Unfortunately, engineers designing consumer grade routers and modems (as well as all sorts of other equipment) misunderstood or ignored this assumption and in an effort to prevent packet loss added large FIFO (first-in-first-out) buffers. If users congest a network chokepoint, typically an outgoing WAN link, the device’s large buffers are filled with packets by TCP and held instead of being dropped. This “bufferbloat” prevents TCP from controlling flow and …

Ghost Table Cells in IE9

By Greg Davidson
February 8, 2013

What’s this about ghosts?

I recently came across an arcane layout issue in my work on a redesigned client site. The problem was specific to Internet Explorer 9 (IE9). The related CSS styles had been well tested and rendered consistently across a variety of browsers including IE7 and 8. Everything was fine and dandy until some new content was introduced into the page for a “Quickview” feature. While all of the other browsers continued to behave and render the page correctly, the layout would break in random and confusing ways in IE9.

The following screenshots compare the correct layout with an example of the broken layout in IE9.

Correct grid layout:

Broken layout in IE9:

The Stage

The following is a list of the factors at work on the page in question:

• Internet Explorer 9
• Browser mode: IE9, Document mode: IE9 standards
• Some content manipulation performed via JavaScript (and jQuery in this case)
• Lots of table cells

Debugging

The page included a list of products. The first “page” of twelve results was shown initially while JavaScript split the rest of the list into several additional pages. Once this JavaScript pagination function was complete, users could cycle …

Getting started with Heroku

By Marina Lohova
February 7, 2013

It’s becoming increasingly popular to host applications with a nice cloud-based platform like Engine Yard or Heroku.

Here is a little guide showing how to join the development of a Heroku-based project. In Heroku terms it’s called “collaborating on the project”. The official tutorial does provide answers to most of the questions, but I would like to enhance it with my thoughts and experiences.

First essential question: how to get your hands on the app source code?

I wish Heroku had something like devcamps service provided, so you wouldn’t need to experience the hassle of launching the application locally, dealing with the database and system processes needed for development. With Heroku the code does need to be cloned to the local environment like this:

$ heroku git:clone --app my_heroku_app

Second, how to commit the changes?

I got this error when trying to push to the repository:

! Your key with fingerprint xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx is not authorized
to access my_heroku_app.
fatal: The remote end hung up unexpectedly

Turned out I needed to add the new identity to my local machine.

Also, if you previously had accounts with Heroku with different email address, …

Install SSL Certificate from Network Solutions on nginx

By Brian Buchalter
February 5, 2013

Despite nginx serving pages for 12.22% of the web’s million busiest sites, Network Solutions does not provide instructions for installing SSL certificates for nginx. This artcle provides the exact steps for chaining the intermediary certificates for use with nginx.

Chaining the Certificates

Unlike Apache, nginx does not allow specification of intermediate certificates in a directive, so we must combine the server certificate, the intermediates, and the root in a single file. The zip file provided from Network Solutions contains a number of certificates, but no instructions on the order in which to chain them together. Network Solutions’ instructions for installing on Apache provide a hint, but let’s make it clear.

cat your.site.com.crt UTNAddTrustServer_CA.crt NetworkSolutions_CA.crt > chained_your.site.com.crt

This follows the general convention of “building up” to a trusted “root” authority by appending each intermediary. In this case UTNADDTrustServer_CA.crt is the intermediary while NetworkSolutions_CA.crt is the parent authority. With your certificates now chained together properly, use the usual nginx directives to configure SSL.

listen                 443;
ssl …