Raible Designs

Thursday October 09, 2008

The Colorado Software Summit and Spring 3.0's SVN In a little over two weeks, my favorite conference begins in Keystone, Colorado. The reason I like it so much is because it's an annual gathering (this will be my 4th year) with friends and it's somewhat like a vacation, except you get to learn a lot. This year I'll be speaking about Appcelerator and Spring 3.0.

A few weeks ago, I wondered How open source is Spring and expressed my frustration in not being able to find the source code. At almost the same time, SpringSource's controversial maintenance policy was announced. Developers booed, Free Spring was founded and SpringSource changed their tune. In addition, someone sent me the FishEye URL for Spring 3.0's SVN. From that, I was able to figure out how to get Spring 3.0's source code.

svn co https://src.springframework.org/svn/spring-framework/trunk spring-3.0

The only bad news is FishEye shows the last change as "17 September 2008 ... (21 days ago)". If Spring 3.0 M1 is supposed to be released any day now, you'd think there would be more SVN commits. Anyone from SpringSource care to comment? Posted in Java at Oct 09 2008, 08:23:21 AM MDT 3 Comments

Tuesday October 07, 2008

Appcelerator with Matt Quinlan This evening I attended the Denver Open Source User Group meeting where the Basic Concepts talk was on Appcelerator. Matt Quinlan (Twitter, Blog, LinkedIn) was the presenter. I arrived 10 minutes late, so I didn't hear any of the intro stuff. Below are my notes from the event.

The Appcelerator developers liked the "onclick" syntax, but found it was too limited to do everything they wanted. Rather than onclick, they use an on attribute. For example:

<div on="click then l:show.box">
Click me
<div>

"DOM Manipulation is JavaScript cruft."

Appcelerator allows you to implement the Observer pattern in the browser. In addition to allowing DOM elements to subscribe to messages, server-side objects (in any language) can subscribe as well. In Appcelerator syntax "l:" means local and "r:" means remote. The messages that are passed to the server are JSON and have payloads. JSON is more popular than XML because you can eval() it and create JavaScript objects from it. Appcelerator allows you to do Declarative Ajax. On the server-side, you can annotation Java and C# classes with @Service to subscribe to messages. In other languages (i.e. PHP), Javadoc-style comments are used.

Tagline: The seamless fusion of RIA and SOA.

Web Expression Language
Goal is to eliminate 90% of the JavaScript you write. Example syntax:

on="[condition] then [action]"

Conditions include DOM events (click, focus, blur, change, mouse events), key events (up, down, press), other (history, drag/drop, selected, resize, iPhone orient, sortXYZ), subscribe to custom message. Actions include Scriptaculous effects (show/hide, fade, move, drop, grow), set element value (static, dynamic, bind), set CSS class or attribute, execute custom JavaScript, publish custom message.

Now Matt is doing a demo on http://try.appcelerator.org. This site consists of a form that allows you to type in Appcelerator code and run it. 3 attributes can be added to any tag: draggable, droppable and resizeable.

Client-Side
Add simple tags to your HTML to inject RIA widgets. Add single property to existing HTML elements for dynamic behavior. Eclipse Plugin built on Aptana, but is generally targeted towards web developers moreso than business analysts (no drag and drop of widgets).

Server-Side
Server-side development done with your IDE of choices. Based on your server-side tehchnology platform. Easily create services using annotations.

App Command
The app command is similar to Rails' GEM command. Allows you to build scaffolding and deploy to cloud (AppEngine, Amazon S3). It also allows you to pulldown components from the main server and auto-updating.

Examples:

• appTunes: widget that wraps Flex Cover Flow widget
• Snapshot: photo editing application
• Radio Javan: Persian music online
• SkyBlox: wireless company

Appcelerator allows you to create prototypes easily by using a JavaScript file with mocks for the server-side objects. In the next version, you can "annotate" the UI and allow end-users to Ctrl+Click on elements and add feedback. For an example of this, see http://dev.appcelerator.com/pearson.

When starting with Appcelerator, you can start by crawling (including appcelerator.js for widgets) then move to walking (decouple server-side and client-side) and finally running (developing working prototypes with mocks for server-side).

"Let's face it, ASP, JSP, PHP and Ruby are just lipstick on CGI." Posted in Open Source at Oct 07 2008, 07:08:19 PM MDT 3 Comments

Xebia RIA Framework Contest Last year, I blogged about the Xebia Web Framework Contest where Struts 2, GWT, Wicket and MyFaces (JSF) were all used to develop the same applications. It seems they've done it again this year, comparing RIA frameworks (English translation) this time.

The winner? Flex - which doesn't surprise me a whole lot.

After this day, the Flex team, has clearly demarcated from its competitors. After two sprints of development and ownership, it could devote the third and final sprint to get rich quick and easy application, focusing only on the features and user experience. It is thanks to the wealth of high-level components, the wealth of documentation available and a maturity framework that the team has made the Flex application's most successful.

Good stuff - thanks Xebia! Posted in Java at Oct 07 2008, 08:06:48 AM MDT 1 Comment

Ajaxified Body: Now with Back Button and Bookmarking Support I uploaded a new version of Ajaxified Body to its demo site a few minutes ago. Changelog:

Added RSH for history and bookmarking and changed to use Prototype and Scriptaculous from Google's CDN.

I found Really Simple History easy to use but poorly documented. Brad Neuberg's AJAX: How to Handle Bookmarks and Back Buttons article was the one that got me over the learning curve. Hat tip to Ignacio for the RSH suggestion.

Let me know if you see any issues or have suggestions for improvement. Posted in Java at Oct 07 2008, 12:14:00 AM MDT 1 Comment

Friday October 03, 2008

Ajaxified Body I've often wondered if it was possible to use Ajax to reload the main content of a web application without reloading the header, menu and footer. SiteMesh allows you to move these common elements to a decorator that gets wrapped around each page. Below is a diagram of how SiteMesh works.

You can read the Introduction to SiteMesh article if you're interested in learning more about SiteMesh's basic features. By default, SiteMesh decorates text/html responses and ignores any other content type (e.g. image/gif). It also contains an <excludes> configuration element that allows you to turn off decoration when a URL matches a certain pattern. For example, the following allows you to disable decoration when "ajax=true" is passed in the URL.

<excludes>
    <pattern>**ajax=true</pattern>
</excludes>

To optimize the loading of an application so the common elements aren't loaded for each page, it should be possible to create an Ajaxified Body where the primary content area (PCA) of the site is loaded via Ajax rather than refreshing the whole page. The header, footer and navigation bar often stays the same from page-to-page, so it doesn't seem to make a whole lot of sense to load them each time the page loads. The image below shows the PCA (of an AppFuse Light application) as a grey square with a red border.

Implementing an Ajaxified Body consists of the following steps:

1. Adding SiteMesh and moving common elements to a decorator.
2. Remove common elements from each individual page (if you're using includes).
3. Configure SiteMesh so decoration is disabled when the requested URL contains "ajax=true".
4. Write JavaScript that modifies all <a href=""> links (and buttons with onclick='location.href') in the PCA to have an onclick handler.
5. The onclick handler should call a JavaScript function that loads the link's URL + ajax=true using XMLHttpRequest (XHR).
6. Add XHR success handling to replace the PCA with the loaded content.
7. Add XHR error handling to go to the URL normally when response.status != 200.
8. Inspect the response HTML for <title> element and replace document.title if exists.
9. Inspect the response HTML for <head> element and append to current if exists.
10. Inspect the response HTML for <script> and <link> elements (JavaScript and CSS) and evaluate them if they exist.

As a proof of concept, I created a prototype using AppFuse Light (Prototype/Scriptaculous for Ajax). You can see a demo at the following URL. You can also download a patch or the source for this project.

http://demo.raibledesigns.com/ajaxifiedbody

Below are a number of things I discovered while writing this prototype:

• The hardest part of implementing this seems to be coding the exceptions. It's possible you'll have some links with existing onclick handlers and you may have to disable "ajaxifying links" for those links.
• A progress indicator is important or the page might load so fast that the user doesn't visually detect it changed. This can lead to a worse user experience because they don't see the flash of the blank page they're used to when a page load occurs.
• While forms can be submitted via Ajax, there's no harm in leaving existing form behavior in place where the full site is reloaded after submitting a form.
• If a particular page needs to change the common elements (header, menu, footer), it should be possible to do that with JavaScript after the PCA content loads.
• If the success/error indicator is outside the PCA, it may need to be populated and displayed/hidden with JavaScript after the PCA loads.

I'm sure my implementation can be improved, but I'm also curious to see what you think of this idea. I know it's not revolutionary, but it's something I'm considering adding by default to AppFuse and AppFuse Light. Do any Ajax frameworks do something like this out-of-the-box?

Update: Thanks to everyone for the great feedback - keep it coming. I agree that adding history support is a must. I'll try to do that in the next day or two. This post has also been featured on Javalobby and Ajaxian.

Update 2: Added history support. Posted in Java at Oct 03 2008, 02:33:09 PM MDT 18 Comments

Wednesday October 01, 2008

Oktoberfest: Best. Vacation. Ever. As mentioned earlier, a good friend (Miller) and I took a vacation to Oktoberfest last week. The flight over was brutal: Denver -> Newark (4 hour layover) -> Paris (2 hour layover) -> Munich. I was pretty disappointed to see "No Service" on my iPhone when we landed in France. This continued in Munich and I quickly decided connectivity wasn't necessary. After a 80 € cab ride from the airport, we arrived at our hotel around 1PM on Monday. We both woke up at 4AM on Sunday to start the journey, so we were pretty beat.

It didn't take us long to decide we had to suck it up and head to "The Tents" at Oktoberfest. We walked the 4 blocks in the rain and quickly ended up in the Armbrustschutzenzelt tent. The crowd was small and we found a table and enjoyed our first Liter.

I won't go into details about how much fun we had during the week, except for these simple stats:

• Made it into The Tents 5 days in a row
• Mostly slept in until 2 or 4PM each day
• No Hangovers (for me at least)

I've uploaded most of the pictures I took to an Oktoberfest 2008 set on Flickr. I would like to thank Peter and friends for being fabulous hosts and showing us a great time on Thursday night. Below is a video I took of what the festivities were like (yes, that is Bon Jovi):

If you ever get a chance to attend Oktoberfest, I highly recommend it. Posted in General at Oct 01 2008, 10:37:49 PM MDT 5 Comments

Saturday September 20, 2008

My Oktoberfest Adventure Begins A few months ago, a friend called me up and asked if I wanted to go to Oktoberfest. He said he had enough miles to cover both our tickets. I couldn't pass up the opportunity and hence we're leaving at the crack of dawn tomorrow for a week in Munich, Germany. We're not taking laptops and we don't plan on doing a whole lot more than having a great time.

If you'd like to see what we're doing on our adventure, you can follow me on Twitter. Posted in General at Sep 20 2008, 10:19:28 PM MDT 13 Comments

Friday September 19, 2008

Performance Testing Memcached Earlier this week, co-workers and I did some performance testing with Memcached. We wanted to see how long it'd take to send different sizes of objects over the wire to Memcached on a remote server.

We setup a simple environment with 2 Mac Pros both running 2 x 2.8 Ghz Quad-Core Intel Xeon processors and 12GB of RAM. We used one machine as a Memcached server and one machine running an application with the addition of a new Servlet Filter. The Servlet Fitler read a size parameter and used it to set the size of the object being written and read from the Memcached server. We used JMeter to put load on the box. The following describes the load and the results.

Write Times
Write tests were performed with a single user executing 1000 sequential remove then writes.

Read Times
Read tests were performed using 50 users with 1 sec. ramp times executing 100 reads each.

During our tests, Memcached was started using the following settings:

memcached -d -m 2048 -M -p 10171 -vv

If you've done similar performance testing with Memcached, we'd love to see your results. Posted in Open Source at Sep 19 2008, 11:29:33 AM MDT 5 Comments

RE: How Open Source is Spring? Peter Mularien has a very well written post titled How Open Source is Spring?: An Analytical Investigation:

This post is to expand on some of the thoughts I posted on the SpringSource Blog in response to Rod Johnson's excellent description of the SpringSource business model and its commitment to development of open source software.

Now that SpringSource has shown an ability to crank out new product releases on a seemingly weekly basis, I wanted to reflect on where Spring is positioned in the Java open source community, and how open the Spring Core project is to work done by the public.

The hypothesis of my experiment occurred to me when I happened to be reviewing Spring JIRA assignments one day. I was curious whether, following the bug assignments, the majority of development on the "Spring Core" projects (including Spring MVC and what we would consider "classic Spring") is performed solely by SpringSource employees.

Peter's post is near and dear to me because I'm doing a What's coming in Spring 3.0 talk at the Colorado Software Summit in October. The only information I was able to find on Spring 3.0 is from random blog posts and Juergen's presentation. When I give talks about technologies, I prefer to dig in and try them before talking about it. With Spring 3.0's source code nowhere to be found, this is very difficult to do.

I really hope Spring 3.0 becomes available in early October. If it does, I hope to upgrade AppFuse, AppFuse Light and Spring Kickstart. If it doesn't, my talk will most likely be a regurgitation of what Juergen's slides have and that's just not right. Posted in Java at Sep 19 2008, 09:54:48 AM MDT 14 Comments

Thursday September 18, 2008

Abbie gets her first tooth and The Bus looks great! Today was quite the day. First of all, Jack and I took Abbie to A Wild Smile to get a couple front teeth yanked. She has her first adult tooth coming in and her baby teeth weren't getting out of the way. Before and after pictures are below:

This afternoon, I drove to Colorado Springs to see The Bus and speak at the Colorado Open Source User Group. The Bus looked great. Motorworks Restorations has done a lot of very detailed work (i.e. replacing corners, stretching the frame, replacing window and door drains) in the last couple of months.

We talked for a good hour about the possibilities in wheels, transmission, engine, suspension, gauges and interior. My favorite topics were the air bags, 6-cylinder 911 engine and safari windows. Click here to see the full set of pictures I took. Quote of the night: "It's going to be better than it was when it was brand new."

After leaving the bus, I delivered my Web Frameworks of the Future Presentation to a bunch of guys (and gals) at a nearby library. It was a fun presentation because I got to meet a lot of folks I had name recognition for, but had never met. All in all, a very good day.

Tomorrow marks my last day of work before I head out on a week's vacation in Munich for Oktoberfest. I have a feeling the days are going to get a lot better from here on out. Posted in The Bus at Sep 18 2008, 11:49:49 PM MDT 1 Comment