Monday, 2 June 2008

RIA + SOA – The AltioLive Solution

I finally managed to get around to reading magazines I picked up at JavaOne and one article stands out for me. SOA World Magazine, June 2008 (http://soa.sys-con.com/read/513263_2.htm) contains an article called "RIA + SOA : The Next Episode, Building next-generation web platform" which describes how RIA and SOA are shifting web applications architecture back to Client Server from Model View Controller (MVC). So I've decided to pick up on this article and analyse it in the context of AltioLive which uses a far simpler implementation methodology – basically all the hard work is done for you.

Complimenting Technologies

I believe Rich Internet Application (RIA) frameworks provide a complimentary technology solution to enabling the user interface for Service Oriented Architecture (SOA). To quote the SOA World Magazine Article

in the standards-based world of HTML, CSS, and JavaScript, RIA developers have to assemble multiple third-party libraries
to build rich user interfaces. AltioLive provides a single framework to enable the rapid development of rich user interfaces and provides a loosely coupled server side framework to make use of SOA and legacy data sources. This enables an Agile development approach to be used to deliver a user front end that can be adapted quickly to meet user requirements.

Poaching the headers from SOA World Magazine

This section takes the headers from the article and replaces the list of possible HTML, CSS and JavaScript options with the simple AltioLive framework implementation. In my opinion having a choice of different frameworks and custom javascript is a maintenance nightmare and is something AltioLive architecture tries to avoid.

  1. Design the "look" of the application.
    For a complex solution requiring branding then a graphic designer can create and define an AltioLive skin. Skins provide the look and feel of borders, scroll bars etc. no need to understand HTML, CSS. For business developers who just want to get on and provide end users with a working system this saves a lot of effort without the need to think about colour codes and styles etc. The design of the user interface is a simple case of dragging and dropping widgets, setting properties and binding them to data.
  2. Integrate Widgets.
    If a component is not defined as a standard control or business widget (AltioLive Composite Control) then a Java developer can create a new Swing or JavaFX widget by extending the base AltioLive custom control or extending existing controls.
  3. Add dynamic behaviour to the user interface
    see next section
  4. Consume Services
    No need to do anything in AltioLive, dynamic user interface interaction with the server comes for free. Plus with AltioLive you get context based routing, ability to poll database tables or HTML service to simulate real time updates to the client. If the infrastructure is available then simply subscribe to a message queue using JMS service requests.
    Not to forget the ultimate aim of connecting to a SOA web service – then just use the Web Service Wizard to create a SOAP service request. No complicated API's to understand and no code to implement, all the business logic is either in the web service or the SQL statement. Validation and data manipulation can all be done in the AltioLive user interface if necessary.
  5. Create Services
    If the server side business logic does not exist then some hard work will be required. Web Services or alternative business services will need to be written, if a short term solution is needed then it may be possible to use AltioLive JDBC Service Requests to retrieve and insert data while putting logic into the user interface.

The article goes on to discuss the need to "Provide an Open Widget Framework", I feel that this is possibly the most important point. The industry needs to have standards that enable Java Applets, Microsoft Silverlight, Macromedia Flash and AJAX widgets to communicate effectively so that a widget that meets the user's needs can be selected regardless of the underlying technology. The key to enabling this standard will probably be JavaScript as it is not tightly coupled to any single vendor solution.

Provide an Integrated RIA Programming Model. This integrated model exists if you use AltioLive. The primary focus for AltioLive is on creating a user interface as simply, quickly and cheaply as possible – through drag and drop and setting properties. The source of the user interface is stored in a plain text file as XML and so can be manually edited if there is a real desire to do so. The drawback of this is that developers can't get their hands as dirty as they may like to. If, as a developer, you really want to get into the depths of the code then a developer can write their own widgets, or focus upon the business logic at the server side. I believe Todd Fast is right when he made the statement "Applications for the masses by the masses: why engineers are an endangered species" (http://www.regdeveloper.co.uk/2008/05/09/developers_endangered_species/ ), the user interface should be about making it easy for the user. Although, I believe there will remain the need for software engineers but their focus should be on providing frameworks and the enablers for the masses to easily create applications.

Provide an Integrated Services Platform. Again AltioLive meets the need to have the following attributes:

  • Support for creating services in any programming language
  • Seamless interoperability between the RIA and SOA tiers
  • Ability to consume local mock services

The AltioLive Presentation Server provides the mechanism to interact with server side components and allows for JMS, JDBC, SOAP, HTTP connections. This means it is possible to make use of direct SQL connections or to write a web service using .Net and call it through the SOAP or HTTP request. While AltioLive is primarily a Java technology it's loosely coupled framework doesn't make Java based services mandatory.

As mentioned through this document AltioLive provides a simple approach to create a service request using one technology and allows migration to another with little or no impact upon the overall application architecture, thus providing seamless interoperability between the RIA and SOA tiers.

Mock services have been a part of AltioLive since its inception. The AltioLive IDE allows a service request to be created with example response data built in, more complex solutions can be created using Composite Service Requests so that different responses can be provided based upon input values. When testing the user interface it may be preferable to replace heavy weight services with a XML file that contains the expected response and then use a HTTP service request to retrieve the data from the XML file. The HTTP service request can simply be replaced with the request to the fully implemented business logic later in the implementation.

Conclusion

The business challenge of moving to SOA

I have yet to work with an organisation that has implemented a SOA architecture from scratch as a green field project, in my experience there has always been legacy integration required to deliver the final solution.

AltioLive overcomes this by allowing the implementation team to expose AltioLive Service Requests. An AltioLive Service Request exposes the same interface regardless of the underlying technology that the data is being retrieved from or written to. This means that an implementation team can initially create a JDBC connection direct to a database and then when a full SOA architecture exposing web-services is in place then the service request can be changed to a Web Service request without any changes to the user interface. This approach enables the rapid development of the user interface required to meet business needs and then a more formal approach can be used to deliver a well defined and structured SOA.

And what about the Enterprise Service Bus (ESB)?

Well using AltioLive the move to a ESB is achieved by modifying the AltioLive server side request to use message queues. If the solution implemented using AltioLive has been well designed then there will be no changes to the XML structure passed to or from the user interface, and now a system will be able to push updates from the message queue to the user interface without any major system changes to the presentation layer.

1 comment:

Anonymous said...

Gary, you may find this project interesting from a SOA perspective.

http://www.ibm.com/developerworks/spaces/zero

Karl