Max Presentation – Flex Development with Cairngorm

At Max Milan last week, I gave a presentation on Flex Development with Cairngorm. The presentation was based largely on the “Cairngorm: Tips and Tricks from the Experts” presentation my colleagues Peter Martin and Eric Garza gave at Max in San Francisco, but after seeing the number of hands raised when Peter asked who was using Cairngorm, I thought I’d change the emphasis (and the content) a bit for the Milan audience.
I wanted to answer a number of common questions surrounding Cairngorm:
* How do I get data from my Commands to my Model?
* How do I get data to my view?
* How can I be notified that new data has arrived on the view?
* How should Responders be implemented?
* How should I use the Model Locator?
So, the presentation is split into three main sections:
1) Cairngorm Overview
The first section is a back-to-basics introduction to Cairngorm, but with a twist. If you’ve been following some of the Adobe Consulting blogs recently, you’ll have seen us talk about the Presentation Model pattern. Another of our consultants, Paul Williams, covered this in his well received series of Presentation Patterns and I show how the Presentation Model fits in with the standard Cairngorm Data Flow.

Cairngorm Data Flow

2) Cairngorm Best Practices
In the second section of the presentation, I provide some Adobe Consulting best practices for the use of Flex and Cairngorm, based on our many and varied engagements on mid to large scale enterprise applications.
The main topics covered are:
* Using the Presentation Model
* Using the Model Locator
* Events, Commands, Responders
* Updating Views with Data
During the talk, I went into detail on the Presentation Model in particular, and how it addresses many of the common questions we hear on handling data in Flex applications.

Presentation Model

I also touched on unit testing with Cairngorm, Cairngorm and Modules, and Cairngorm and Data Management Services (part of LiveCycle Data Services).
3) Cairngorm Myths and Anti-Patterns
The presentation also gave me the opportunity to challenge a number of the misconceptions and misunderstandings I have seen on blog posts and architecture face-off discussions at conferences. I also spoke about some of the recurring mistakes we see people make when using Flex and Cairngorm. I covered the following:
* Do I Always Need to use a Framework?
* Do I Need to use every Cairngorm Pattern?
* Business Logic in Cairngorm Classes
* Use of the ModelLocator
* Use of Commands and Responders
* Use of the Controller
I hope to find time to provide more details on these best practices and myths in future blog posts.
At Max San Francisco, Peter Martin also announced the launch of the Cairngorm Plugin for FlexBuilder to allow the quick creation of FrontControllers, Events and Commands. The presentation ends with some details of that, and some road-map details.

Cairngorm Plugin

My Max Milan presentation can be found on Adobe acrobat.com, here. You can download it via the Download link near the top-right of that page.

FlexUnit on Adobe Open Source

flexunit.jpg
Following on from the news that Cairngorm has been moved to Adobe Open Source, it is my pleasure to announce that FlexUnit, the unit testing framework for Flex applications, now has a new home on Adobe Open Source.
FlexUnit started its life almost 5 years ago, when I first wrote AS2Unit; at that time, it home was the iteration::two website. FlexUnit was borne from that project, and was released shortly after Flex 1.0 in March 2004.
With the release of Flex 2, a team from Adobe Developer Relations migrated the framework to ActionScript 3 and gave it a new home on Adobe Labs. However, it was soon on its move again, and ended up on Google Code as a 0.85 release of as3flexunit.
Since that time, a number of bugs have been identified, and a number fixed, but there has been no real visibility of ownership; no-one has the responsibility to build and test and release new versions to the community and the 0.85 version is fast approaching 2 years old.
We see this move as bringing FlexUnit back to its Adobe home, where it can get the attention and care it deserves.
Adobe Open Source brings a number of benefits:
* Source available via a Source Control System (Subversion)
* Availability of a bugbase for bugs and enhancement requests (JIRA)
* Developer forums for the discussion of features and roadmap
* Ability to submit code patches
Alongside this move, we’ve also taken the opportunity to do some bug fixes and have also add some new features to FlexUnit. The codebase for this release is based on revision 20 from Google Code. We realize that there have been a few subsequent changes made to that codebase since we had to branch to make our own bug fixes and enhancements, and we look to the community to reintegrate any of these changes, as necessary. We have chosen to go down this route rather than delay the release further.
The most visible set of changes to FlexUnit, and something you’ve probably already noticed from the screenshot above, is in the graphical test runner, designed by the User Experience team at Adobe Consulting.
Within the runner, we’ve added more information about the tests being run. We’ve provided the average number of asserts per test case, and also the number of asserts in each individual test case.
flexunit-summary.jpg
When tests do fail, we’ve extracted the failure information to make it clearer to the user, and, so long as you have compiled your tests with debug set to true, and are running with the debug flash player, you will also see the stack trace, to give that extra level of information not necessarily previously available.
flexunit-results.jpg
Finally, you can now also filter your test results, for those larger projects where you have hundreds of test cases.
You can filter on individual test case names, test names, expected results or actual results, and also choose to see results based on all test cases, only those with errors or failures, or just empty test cases.
flexunit-filter.jpg
We are incredibly excited about this move, and look forward to the community getting involved through the submission of enhancement requests, code patches, documentation and taking part in the discussions around FlexUnit.
I was hoping to contact the project members of the existing as3flexunit project; unfortunately, Google Code does not let me easily identify the current members. So, if you wish to contribute to the project, please contact me.
The FlexUnit home page on Adobe Open Source can be found here.

Cairngorm on Adobe Open Source – One Week On

So, Cairngorm has been on Adobe Open Source for over one week now, and I thought I’d summarize what’s happened since.
It has been interesting to watch the community response to my announcement. To Adobe Consulting, this was a move of an already open source project from Adobe Labs to Adobe Open Source, but while the response has been extremely positive, many of the reports read as if Cairngorm becoming open source was something new.
I guess this says something about our previous messaging, and the fact that the setup on Adobe Labs wasn’t the same as Adobe Open Source, where we now a full governance and have the source code hosted on Subversion and available to all, rather than a single ZIP download of the source.
As i explained in my announcement, we made a conscious decision not to add any new features in the process of the move. We did, however, provide the facility for community feedback, and already, we’ve had a good amount of involvement.
Over on the Cairngorm Forums, we’ve had various discussions, including those on creating a test suite for Cairngorm, tooling support for Cairngorm within Flex Builder and how we should approach extending Cairngorm.
The Cairngorm Bugbase has sprung into life too, and Christophe Herreman has already submitted patches containing some initial unit tests, alongside two other bug reports with patches. We’ve also had an enhancement request, for better support for Cairngorm with Flex Modules.
JIRA, on which the Cairngorm bugbase runs, has a voting facility, so please get invovled, and vote on the bugs and enhancement requests you think should be part of a future release.
What next?
A team from Adobe Consulting met on Monday of this week to discuss the Cairngorm roadmap, both in the short-term, to apply the patches provided and ensure Cairngorm is fully up to date with the latest releases of the Flex SDK, BlazeDS and LiveCycle Data Services, and also looking to the future, and Cairngorm 3.
We’ll be socializing our thinking over the coming weeks
In the meantime, we encourage you to get involved in the discussions taking place on the forums or to submit enhancement requests to the bugbase.

Cairngorm Moved to Adobe Open Source

Adobe Consulting is pleased to announce that the Cairngorm Micro-architecture has moved onto Adobe Open Source.
Its hard to believe that Cairngorm is approaching 4 years old – Steven and I announced it at the Max conference in New Orleans in October 2004 and the first version was released soon thereafter.
We’ve gone through a number of different versions since then, but each one has always held true our vision: Provide a lightweight MVC architectural framework around which to build Rich Internet Applications with Adobe Flex or Adobe AIR.
The latest version, Cairngorm 2.2.1, was released back in October 2007 and, although we at Adobe Consulting consider that being a good reflection as to the maturity of the framework, there have been some questions on when the next release would be made available and what new features it would have, alongside some specific feature requests.
At Adobe Consulting, we’ve always had a minimalist approach to Cairngorm; we don’t want to add feature for feature sake, add functionality that doesn’t belong within an architectural framework, or introduce another design pattern into the mix because it’s the latest fad in the software industry. The framework is there to allow us to build well-architected software solutions, and we’ve only ever added features we truly believe helps us do that.
There are no new features in this release – at this time we are simply moving Cairngorm 2.2.1 from Adobe Labs to Adobe Open Source.
However, we do listen to the community and to our customers, and this announcement is in response to this invaluable feedback. We hope that this launch will emphasize the commitment that Adobe has to the framework, and reinforce the message that the framework is the one that Adobe Consulting visibly advocates.
There are many benefits to having Cairngorm on Adobe Open Source. Alongside having a well defined home for downloading the framework, its documentation and samples, Adobe Open Source also provides additional resources one would expect of an open source project:
* Source available via a Source Control System (Subversion)
* Availability of a bugbase for bugs and enhancement requests (JIRA)
* Developer forums for the discussion of features and roadmap
* Ability to submit code patches
Alongside this move, we are also introducing a level of governance, a charter that explains how the Cairngorm project will be managed, and how leaders in the Flex community can get involved in the project.
We are also extending an open invitation to the community to submit bugs or feature requests and take part in the Cairngorm discussion forums.
The community has read-only access to the Cairngorm source code by default, and contributors will also be able to submit code patches.
We are incredibly excited about this move, and look forward to the community getting involved in the framework, through the submission of enhancement requests, sample applications, code patches, documentation and taking part in the discussions on the future direction of Cairngorm.
The Cairngorm home page on Adobe Open Source can be found here.

Cairngorm – Commands and Responders

Recently, I’ve seen a few questions around Cairngorm and how commands and responders fit together when using asynchronous services with Flex. I’d like to clarify a couple of points.

A Command need only implement the Flex IResponder interface if it is to be the responder for an asynchronous service call.

This is probably obvious to many, but I’ve seen Command classes which implement IResponder, but don’t do any ansychrnous service calls and have empty result() and fault() methods. In this cases, the Command should implement the ICommand interface only and not the IResponder interface.

The Command class does not have to be the responder for asychronous service calls.

I’ve not seen many implementations like this, but the Cairngorm command pattern is designed in such a way that your responder can be an instance of another class, as in this example:

public class AddTaskCommand implements Command
{
public function execute( event : CairngormEvent ):void
{
var addTaskEvent : AddTaskEvent = event as AddTasksEvent;
var task : Task = addTaskEvent.task;
var addTaskResponder : AddTaskResponder = new AddTaskResponder( task );
var delegate : TaskDelegate = new TaskDelegate( addTaskResponder );
delegate.addTask( task );
}
}

public class AddTaskResponder implements IResponder
{
private var task : Task;
public function AddTaskResponder( task : Task )
{
this.task = task;
}
public function result( event : Object ):void
{
//handle the result here
}
public function fault( event : Object ):void
{
//handle the fault here
}
}

This implementation allows better separation of logic and potential reuse of responders, and also makes things easier to test.

Cairngorm 2.2.1 Released

After a few months of being in beta, Cairngorm 2.2.1 for Flex has been released on Adobe Labs.

There is nothing new in this release over previous releases; it’s only purpose is to align Cairngorm with the moving of SWC libraries in Flex 2.0.1 with Hotfix 2 and LiveCycle Data Services 2.5.x.

Flex Scheduling Framework – Now on FlexLib

The Flex Scheduling Framework, previously on Adobe Labs, now has a new home, as part of the FlexLib project on Google Code.

The Flex Scheduling Framework was borne out of Adobe Consulting engagements, as is not part of the Flex SDK. As such, maintenance and bug fixes were mainly community led, with Adobe Consulting staff members spending their own time to apply any fixes.

The latest release on FlexLib includes a number of bug fixes when compared to the original version that appeared on Adobe Labs. I’d like to give a thanks to those people who identified bugs and submitted fixes, and to Alex Uhlmann who applied those fixes, and some of his own, to the framework before we handed it over to FlexLib.

FlexLib contains a full source code repository, so if you want to see any new features as part of the Flex Scheduling Framework, download the source and submit your proposed changes back, for inclusion in the code repository and subsequent framework builds.

The full set of ASDocs for the Flex Scheduling Framework can be found on FlexLib, but other content is quite light on Flex Lib at present – we will migrate the Adobe Labs content to FlexLib over time.

As always, your feedback is welcome.

New Release – Cairngorm 2.2.1 for Flex 2.0.1 with Hotfix 2

I posted last Friday about the release of Hotfix 2 for Flex 2.0.1, and how the moving of classes between the core Flex SDK and LiveCycle Data Services was causing a compiler error unless you had fds.swc on your library path.

The fix at that time was to include fds.swc on your library path, even if you did not use or need LiveCycle Data Services 2.5.

I’ve now created a new build of Cairngorm and Cairngorm Enterprise that is aligned with the new packaging of Flex 2.0.1 with Hotfix 2 applied and with LiveCycle Data Services 2.5. This packaging should also work for standard Flex 2.0.1 installations.

I’ve had to put this package together quite quickly and full testing hasn’t taken place, so this release is a Beta for now.

The only change in this release is the moving of the Consumer and Producer service locator methods from the base Cairngorm ServiceLocator into the Cairngorm Enterprise EnterpriseServiceLocator class.

You can download the packages here:

I’ve leave these package on this blog for now, until feedback has been received, and then I’ll get them moved over onto the Cairngorm page on Adobe Labs.

Flex 2.0.1 Hotfix 2 and Cairngorm

Flex 2.0.1 Hotfix 2 has been released today, containing a collection of Flex 2.0.1 bug fixes.

As part of this release, some classes, which are not required as part of the core SDK, have been moved into Flex Data Services (FDS), now rebranded LiveCycle Data Services 2.5 (LCDS 2.5) and newly released.

However, because the ServiceLocator class of Cairngorm has a soft reference onto the Flex framework’s Consumer class, applying Hotfix 2 will cause the following compiler error in your Cairngorm application, unless you have fds.swc on your classpath.

1046: Type was not found or was not a compile-time constant: Consumer.

We will be releasing another version of Cairngorm and Cairngorm Enterprise, which will align themselves with the new class locations in Hotfix 2, and also be compatible with the standard Flex 2.0.1 release. In the meantime, if you update to Hotfix 2 or switch to LiveCycle Data Services 2.5, ensure you have fds.swc on your classpath. You can get this from the new LiveCycle Data Services 2.5 release.

Cairngorm 2.2 – Cairngorm Enterprise

In today’s post about the recent release of Cairngorm 2.2, I’ll give the reasoning behind the most obvious change made to the distrubution of the framework – the splitting of it into two parts, Cairngorm and Cairngorm Enterprise.

The main reason for the change at this time was to remove Cairngorm’s dependancy, introduced in Cairngorm 2.1, on the Flex Data Management Services library, fds.swc. This dependency forced developers to download Flex Data Services, even if they were using Cairngorm with a relatively simple applications that used RemoteObject, HTTPService or WebService only.

Mea culpa, as they once said.

However, this change also hints at the longer term roadmap view of where Cairngorm is heading.

Our vision is that Cairngorm will have a core framework, which mid-sized applications will use. Alongside that, we foresee the need for a set of additional modules, for use in enterprise-scale applications.

These modules will contain repeatable, best-practice solutions to common application problems and will address areas such as:

  • Extended support for Flex Data Management Services
  • Extended support for Flex Messaging Services
  • Platform specific module for Apollo
  • Product specific module for LiveCycle Enterprise Suite
  • Security and authentication modules
  • Others we haven’t thought about yet

The modules could vary in architecture, from a simple set of command, delegate and service definitions, or even some server side Java code (eg, for LiveCycle ES), through to new sets of classes that implement the common patterns we see emerging in our solutions.

We expect the modules to surface as best practices out of our day-to-day consulting work, rather than by us attempting to determine the solutions upfront. As such, we cannot commit to any specific date for any new features, but we can say that they will remain free and open-source.

As always, we welcome your feedback on our thoughts.