GWT - best practices

GWT tutorials is a good way to learn basics and even to build simple prototypes, but it's certainly not enough information to start building real life application. That's why I was so glad to find this video from Google I/O 2009 which describes best practices for architectecting GWT application.

-=Oleg=-

New Direction - Google App Engine

As it often happened in developers life, as soon as you become an expert in something, the life throws you a new project which requires you to learn brand new  languages, platforms, frameworks, technologies, etc... Suddenly your work day routine changes from 80% coding and 20% research to 99% of learning and researching.

Only six month ago I started working with Silverlight. We had some fun playing with new power tool, we've built the a series of prototypes... and that was the end of Silverlight journey.

New mission is Google App Engine.  Our language of choice is Java. My experience with Java - none. So far looking at zillions of Java frameworks makes me dizzy. After spending 2 days on learning Struts 2 I've realized that the learning curve is expected to be very deep. I'm diving in... - wish me good luck.

-=Oleg=-

More about IIS performance

One more article about IIS performance from trusted source i.e. from Microsoft:

http://blogs.technet.com/mscom/archive/2008/06/09/microsoft-com-operations-performance-analysis-of-iis-7-0-windows-server-2008.aspx

-=Oleg=-

SVN Rollback - restoring deleted files and folders

Preface

I'm not an expert in SVN version control and I don't like using command line. I'm regular Windows user and so it was easy for me to learn how to use "Commit" and "Update" buttons in TortoiseSVN. It was easy until one day when I had to figure out how to restore delete folders.

A day when sources disappeared

One beautiful morning I checked out my sources from SVN and discovered that the most of the files and folders are gone. Apparently the night before one of the developers was cleaning SVN working folder on his machine and ... Well, if you don't know what that big red button is for it might be not a good idea to press it...

So, if don't know what to do - ask Google. Google said - don't worry, it's impossible to lose anything in SVN, just do the reverse merge using following command line params... 

The problem is I didn't want to use command line. I wanted to use beautiful TortoiseSVN UI for that. So, I found "Revert to this revision" and "Revert changes from this revision" and thought my problem is solved, but for some reason SVN was failing this task with an error "'/svn/sources/!svn/bc/373/Test' path not found". Finally, after asking an SVN expert, I figured that there was a small detail which I was missing. The revision of your working copy has to be a "HEAD".

Steps to recover deleted files or undo the submit in SVN:

1. Get the HEAD revision from SVN it to your working folder. Working folder is the key word here. (I suggest using temporary folder)


2. Click on Show Log


3. In the Log window, select revision you want to undo and click on the "Revert changes from this version" in the popup menu. This will execute the merge command of the corresponding revisions.


4. Wait for SVN to update your working folder. Working folder is the key word again. SVN updates your working folder first, so you can review the change before you commit it to SVN.


5. Make sure your sources merged correctly and then commit the change to SVN.

Best luck recovering your sources!

-=Oleg=-

IIS Performance

Yesterday we had a little debate in the office about the max number or requests IIS can handle per second. So I did a little research and found that majority of the people are not able to go higher than 300-600 requests/sec, however some claim they were able to get 20000 req/sec. I guess it depends on how much processing work your request does i.e. if IIS is simply returning a HTML page or if it processes ASP.NET page doing authentication, making database requests and constructs the HTML page at the end.

Anyhow, I discovered that IIS 7  has some interesting features wich I was not aware of http://blogs.iis.net/bills/archive/2007/05/07/iis-vs-apache.aspx. I especially like the one that allows you to Troubleshooting Failed Requests Using Tracing in IIS 7.0 http://learn.iis.net/page.aspx/266/troubleshooting-failed-requests-using-tracing-in-iis-70/.

-=Oleg=-

Silverlight Styling

Changing the styling of the Silverlight controls is simple. It’s somewhat similar to CSS, but it's more robust and syntax is completely different. What is different in Silverlight and WPF is that you can completely re-define control’s UI and behavior using styles. It took me about 20 minutes from absolute zero to the “Aha!” moment and become an expert in styling WPF and Silverlight applications. Here are the 3 links that helped me to clear the mistery behind Silverlight styles:

1.       Using Style Elements to Better Encapsulate Look and Feel – a good example of how to change control’s properties using styles

2.       Using Control Templates to Customize a Control's Look and Feel – a step further that shows how to make control look anyway you want. In other words how to draw control’s UI from scratch or combine several controls into one. All using styles! Pretty amazing yet simple.

3.       MSDN: Customizing the Appearance of an Existing Control by Using a ControlTemplate – the final piece of puzzle is about how to make control to react on events like Pressed or Disabled and change its appearance. Just few more words about this. Basically every control has a list of pre-defined events (they called states in Silverlight) which can be referenced by ControlTemplate. The list of states differs for each control. This information is available in MSDN on control’s Class page as a list of TemplateVisualStateAttribute attributes applied to the class.

-=Oleg=-

Silverlight 3 has been released

Long awaited Silverlight 3 has been released. Here is the download link:

http://www.microsoft.com/silverlight/get-started/install/default.aspx

New features:

Media: New codec support (H.264, AAC, MPEG-4), raw bitstream Audio/Video API, and improved logging for media analytics

Graphics: GPU Acceleration and hardware compositing, perspective 3D, bitmap and pixel API, pixel shader effects, and Deep Zoom improvements

SEO: Deep linking

Application development: multi-touch support, 60+ controls available, and library caching support

Data: Data-binding improvements, validation error templates, server data push improvements, binary XML networking support, and multi-tier REST data support

-=Oleg=-