Blog from Feb 03, 2012

The last time AppFuse had an update done to its look and feel was in way back in 2006. I've done a lot of consulting since then, which has included a fair bit of page speed optimization, HTML5 development and integrating smarter CSS. It was way back in '05 when we first started looking at adding a CSS Framework to AppFuse. It was Mike Stenhouse's CSS Framework that provided the inspiration and my CSS Framework Design Contest that provided its current themes (puzzlewithstyle, andreas01 and simplicity).

Since then, a lot of CSS Frameworks have been invented, including Blueprint in 2007 and Compass in 2008. However, neither has taken the world by storm like Twitter Bootstrap. From Building Twitter Bootstrap:

A year-and-a-half ago, a small group of Twitter employees set out to improve our team’s internal analytical and administrative tools. After some early meetings around this one product, we set out with a higher ambition to create a toolkit for anyone to use within Twitter, and beyond. Thus, we set out to build a system that would help folks like us build new projects on top of it, and Bootstrap was conceived.
...
Today, it has grown to include dozens of components and has become the most popular project on GitHub with more than 13,000 watchers and 2,000 forks.

The fact that Bootstrap has become the most popular project on GitHub says a lot. For AppFuse.next, I'd like to integrate a lot of my learnings over the past few years, as well as support HTML5 and modern browsers as best we can. This means page speed optimizations, getting rid of Prototype and Scriptaculous in favor of jQuery, adding wro4j for resource optimization and integrating HTML5 Boilerplate. I've used Twitter Bootstrap for my Play More! app, as well as some recent client projects. Its excellent documentation has made it easy to use and I love the way you can simply add classes to elements to make them transform into something beautiful.

Last week, I spent a couple late nights integrating Twitter Bootstrap 2.0 into the Struts 2 and Spring MVC versions of AppFuse. The layout was pretty straightforward thanks to Scaffolding. Creating the Struts Menu Velocity template to produce dropdowns wasn't too difficult. I added class="table table-condensed" to the list screen tables, class="well form-horizontal" to forms and class="btn primary" to buttons.

I also added validation errors with the "help-inline" class. This is also where things got tricky with Struts and Spring MVC. For the form elements in Bootstrap, they recommend you use a "control-group" element that contains your label and a "controls" element. The control contains the input/select/textarea and also the error message if there is one. Here's a sample element waiting for data:

Below is what that element should look like to display a validation error:

You can see this markup is pretty easy, you just need to add an "error" class to control-group and span to show the error message. With Struts 2, this was pretty easy thanks to its customizable templates for its tags. All I had to do was create a "template/css_xhtml" directory in src/main/webapp and modify checkbox.ftl, controlfooter.ftl, controlheader-core.ftl and controlheader.ftl to match Bootstrap's conventions.

Spring MVC was a bit trickier. Since its tags don't have the concept of writing an entire control (label and field), I had to do a bit of finagling to get things to work. In the current implementation, Struts 2 forms have a single line for a control-group and its control-label and controls.

With Spring MVC, it's a bit more complex:

You could probably overcome this verbosity with Tag Files.

Figuring out if a control-group needed an error class before the input tag was rendered was probably the hardest part of this exercise. This was mostly due to Bootstrap's great documentation and useful examples (viewed by inspecting the markup). Below are some screenshots of the old screens and new ones.

Before the holiday break, I spent some time upgrading AppFuse to use the latest releases of Spring and Spring Security. I started with Spring Security in early December and quickly discovered its 3.1 XSD required some changes. After changing to the 3.1 XSD in my security.xml, I had to change its <http> element to use security="none" instead of filters="none". With Spring Security 3.0.5, I had:

After upgrading to 3.1, I had to change this to:

The next thing I had to change was UserSecurityAdvice.java. Instead of using Collection<GrantedAuthority> for Authentication's getAuthority() method, I had to change it to use >Collection<? extends GrantedAuthority>.

Lastly, I discovered that SPRING_SECURITY_CONTEXT_KEY moved to HttpSessionSecurityContextRepository. Click here to see the changelog for this upgrade in AppFuse's FishEye.

You can read more about what's new in Spring Security 3.1 on InfoQ. I'm especially pumped to see http-only cookie support for Servlet 3.0. I discovered Spring Security didn't support this when Pen-Testing with Zed Attack Proxy.

Upgrading to Spring Framework 3.1
Compared to the Spring Security upgrade, upgrading to Spring 3.1 was a breeze. The first thing I discovered after changing my pom.xml's version was that Spring Security required some additional exclusions in order to get the latest Spring versions. Of course, this was communicated to me through the following cryptic error.

Without these additional exclusions, Spring Security pulled in Spring 3.0.6. I had to exclude spring-expression, spring-context and spring-web from spring-security-taglibs to get the 3.1.0.RELEASE version of Spring.

I also had to exclude spring-context from spring-security-config and spring-context and spring-expression from spring-security-core. Isn't Maven wonderful?

After making these changes, I got a bit further, but ended up being blocked by a bug in Tapestry 5's Spring support. Basically, after upgrading to Spring 3.1, I started seeing the following error:

Luckily, I was able to easily fix this with advice I found on Tapestry's mailing list. Unfortunately, even though I submitted a fix on December 15th, it didn't make it into Tapestry's 5.3.1 release on December 21st. As soon as Tapestry 5.3.2 is released, I hope to get the AppFuse's build passing again (it's currently failing).

I hope this article helps you upgrade your AppFuse-started applications to the latest versions of Spring and Spring Security. Over the next few weeks, I'll be exploring many of Spring 3.1's new features and implementing them as I see fit. Right now, I'm thinking environments/profiles, Servlet 3 / Java 7 support and Hibernate 4 support. These seem to be the best new features to learn about for my talk in a few weeks.