Tuesday 18 October 2011

Generating SwitchYard BPEL applications

With the release of Savara Eclipse Tools 2.0.0.M5, it is now possible to generate BPEL projects that can be deployed to the new jboss.org ESB called SwitchYard. This post explains how to generate an example application and deploy it to the ESB. BPEL support will be available in version 0.3 of SwitchYard, due to be released early November 2011.

Setting up your Eclipse environment

First step is to set up your Eclipse environment. If you don't already have an Eclipse environment, then we suggest downloading the JEE version of Indigo from http://www.eclipse.org/downloads/.

Once you have installed Eclipse, run it up and go to the Help->Install New Software menu item. Enter the Savara Update Site (http://downloads.jboss.org/savara/releases/updates/2.0.x) location into the top text field and press the return key. In the main panel it will show a tree with the categories Savara and Savara Dependencies at the top level. Select both of these categories, and then press the Finish button. Follow the instructions presented by the update manager until you will be requested to restart your Eclipse environment.

Importing the Purchasing Example project

The purchasing example can be found here: http://downloads.jboss.org/savara/examples/purchasing.zip

Once this file has been downloaded, go to the Eclipse environment and select the context menu from within the Project Explorer. Select the "Import ...->General->Existing Projects into Workspace" menu item, then when the dialog is displayed, choose the "Select archive file" radio button and use the "Browse" button to locate the downloaded purchasing.zip file.

When the 'Finish' button is pressed, the purchasing project will be imported into the Project Explorer.

Generate the SwitchYard BPEL Projects

When the purchasing project is expanded, you will find a choreography file in the top level folder called PurchaseGoods.cdm. Select the context menu for this file, and choose the menu item "Savara->Generate->Service", as shown in the following image:


This menu item will cause the following dialog to be displayed:


Select the 'Switchyard BPEL' Service Type for each of the service roles, and then press the 'OK' button to generate the three projects.

If you expand the PurchaseGoodsProcess-Store project, you will see that the artifacts for the Switchyard BPEL application are primarily contained within the src/main/resources folder:


Adding Implementation Details

The generated project contains an 'abstract' version of the BPEL process definition, outlining how it interacts with any consumers, or external services. However it does not contain all of the implementation logic, as this is not available within the choreography description from which the BPEL process was generated.

As a short cut, we have provided a version of the BPEL processes for this example, with the implementation details fully completed. This can be downloaded from here: http://downloads.jboss.org/savara/examples/purchasing_bpel_impl.zip

In this zip you will find three BPEL processes. These should be used to replace the generated versions - although if curious, first copy them to another location in your Eclipse environment, and perform a comparison to see the differences. For example, select the PurchaseGoodsProcess_Store.bpel from the generated project, and the version obtained from the downloaded zip, and use the "Compare With->Each Other" menu item and you will see:


The generated version on the left contains the main structure of the process, and the interaction statements (e.g. receive, reply, invoke). The 'one we prepared earlier' version on the right adds assignment and condition statements.

Running the Example

The final step is to package and deploy the SwitchYard applications. The SwitchYard version we will be using is the 0.3 AS7 based distribution. (Note: version 0.3 will be released early November 2011).

For each of the generated projects, from the project node in the explorer select "Export ..." from the context menu. From the dialog select "Java->JAR file", and in the next dialog specify the location of where the Jar should be stored. For example, you could create a Store.jar, CreditAgency.jar and Logistics.jar.

Once the SwitchYard server has been started, using the "./standalone.sh" command in the bin folder, copy the three SwitchYard BPEL applications into the $AS7/standalone/deployments folder.

When a service has been successfully deployed, you will see messages similar to the following associated with the LogisticsService:

14:46:48,820 INFO  [org.apache.cxf.endpoint.ServerImpl] (MSC service thread 1-2) Setting the server's publish address to be http://127.0.0.1:18001/LogisticsService
14:46:48,858 INFO  [org.jboss.as.server.controller] (DeploymentScanner-threads - 1) Deployed "Logistics.jar"

Lastly, using your favourite SOAP client (e.g. SOAPUI), send the following message to http://127.0.0.1:18001/StoreService:

<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:stor="http://www.jboss.org/examples/store">   <soapenv:Header/>
<soapenv:Body>
<stor:BuyRequest id="1" product="bike" customer="Joe"/>
</soapenv:Body>
</soapenv:Envelope>

you will get a response:

<soap-env:Envelope xmlns:soap-env="http://schemas.xmlsoap.org/soap/envelope/">
<soap-env:Header>
<soap-env:Body>
<BuyConfirmed id="1" xmlns="http://www.jboss.org/examples/store" />
</soap-env:Body>
</soap-env:Header>
</soap-env:Envelope>

If you now change the request so the customer is "Fred", then you will receive an 'AccountNotFound' fault.

Thursday 21 July 2011

Savara 2.0.0.M4 is released with initial BPMN2 and SCA support

The Savara team are pleased to announce the release of milestone 4 of Savara 2.0. The Savara project provides tools in support of the Testable Architecture methodology, which aims to ensure that artifacts defined at different stages of the software development lifecycle are valid against each other, ensuring that the delivered system meets the original business requirements.

The main new features in this release are:

  • First 'technical preview' of the choreography to BPMN2 process model generation. Currently this still uses the WS-CDL based choreography, but will use the BPMN2 choreography model in a future release.
  • Generation of SCA Java based service implementations from a choreography. This creates a Java project, including the SCA composite descriptor, WSDL and XSD files (representing the external service contract), the Java interfaces and template Java service implementation class.
  • Update to simulation framework, to enable different roles within a scenario to be simulated against different models.
  • SCA Simulator, to enable a scenario to be simulated against SCA Java based service implementations.
  • Upgrade to latest version of Scribble (draft 1.0 version of protocol spec). Scribble is a notation for representing protocols, and provides the underlying canonical model for describing behaviour across artifacts in Savara.
  • Many bug fixes.

Full details can be found here: https://issues.jboss.org/secure/ReleaseNote.jspa?projectId=12310870&version=12316424

Thursday 7 April 2011

Scenario format and editor changed in Savara 2.0.0.M2

Savara 2.0.0.M2 has just been released as an Eclipse update site version only. This is because all the work for this milestone has been in the core OSGi bundles and the Eclipse plugins, so no reason to build a new server integration distribution.

The main purpose of this milestone release is to perform some refactoring to enable extensibility in the contract/service generation areas, and the simulation of roles defined in a scenario. This has resulted in two main changes:

1) In previous releases the particular target generation format was selected on the context menu associated with the choreography description. From this milestone release, the generation menu now only provides two options, Contract and Service. These options launch a dialog window that enables the user to select the specific generation format for all relevant roles in the source model. So this means that all of the relevant contracts or services can be generated in one step, potentially using different target formats. Currently only BPEL and WSDL are supported.

2) New simplified Scenario format and associated editor. The new scenario format only contains the basic information required (equivalent to the business view in Savara1 scenarios) and is no longer tied to a particular (ws-cdl) model, which has its pros and cons. The pros are that it can be used against multiple models, which also means that each role can be simulated against a different model (or service implementation). The cons relate to the ease of specifying the scenario, as there is no direct reference model. However scenarios are intended to be specified before the model (in terms of the methodology when used top down), so in those situations a model wouldn't be available anyway. A future enhancement could be to enable artifacts to be associated with the scenario in a less explicit manner, which could be used by the editor to infer information that could be useful to the user in constructing the scenario.

Note that currently there are no docs for these changes. The aim is to make the features available as soon as possible, to encourage feedback - therefore a quick overview of the new scenario capability is described below.

The first change is that Savara scenarios (as opposed to the pi4soa Scenarios previously used) have their own category in the New menu.


The scenario editor itself is very similar. From first appearence it only looks like a few of the palette items have disappeared. These are the 'Assert State' and 'Record State' items, which were very limited in their capability and specific to WS-CDL. A future enhancement of the new scenario format could investigate ways of specifying assertions.


The main change to note here is the properties associated with the selected message link. With the new scenario format a message link now only identifies whether an error is expected, the optional operation and fault names, and one or more parameters. A parameter is comprised of two pieces of information, the parameter type and the URL to the message value.

The next change is the way in which scenarios are simulated. Previously when the simulation was triggered, it would immediately simulate the scenaro against the WS-CDL choreography description that had been directly referenced from within the scenario.

In this new version, performing the simulation action (i.e. pressing the green 'play' button or selecting scenario->simulate on the context menu), will show the following dialog window:


The main region of the dialog is composed of a repetitive group, one per role in the scenario. This group enables the (a) model (i.e. choreography), (b) role within the model, and (c) simulator, to be selected. There are also checkboxes at the top of the dialog (checked by default) that enable the same values for the model and simulator to be applied to all roles within the scenario - making it more efficient in the case where only a single model and simulator implementation is being used.

To load the model, simply press the '...' button by the first role's model text field. This will display a dialog box that can be used to find the appropriate model. The list of model roles, and simulators, will update once a model has been selected, to reflect the available roles and simulators that are appropriate to the model. So if you select any old file, then don't expect any values to appear in these comboboxes. Currently the only model type supported is the .cdm files.

In our example project we have a PurchaseGoods.cdm model. When this is selected, the dialog window makes its best estimate at the model role mappings:


When the OK button is pressed, this will trigger the simulation, which will be reflected in the graphical representation of the scenario as before:






Feedback on these new changes, and any enhancements required, would be welcome. Simply post to the user forum or raise an issue in the Savara jira.


To install the release, simply download the JEE version of Eclipse Helios, and then install the following using the "Help->Install New Software" menu option:

1) Savara 2.0.0.M2 from: http://downloads.jboss.org/savara/releases/updates/2.0.x

and if you wish to generate and/or view BPEL processes, then

2) SOA Development->JBoss BPEL Editor from: http://download.jboss.org/jbosstools/updates/stable/helios/

The example project used above can be found here: http://downloads.jboss.org/savara/releases/2.0.0.M2/samples.zip


The details for this release can be found here: https://issues.jboss.org/secure/ReleaseNote.jspa?projectId=12310870&version=12316056

Savara at last years SOA and Cloud Symposium

Last year in Berlin I had the fortune to speak back to back at the SOA and Cloud Symposium and then at JBoss World.

The SOA and Cloud Symposium released the following recording of the talk. Hope you enjoy it.

Happy to send the ppt to anyone that wants it. Just email me at steve.ross-talbot@cognizant.com.

Cheers

Steve T

Wednesday 6 April 2011

First glimpse of the BPMN2 editor that will be used in Savara

Red Hat recently commissioned the development of a BPMN2 editor from a company called Codehoop. This editor will become the core of the BPMN2 based tooling in Savara - hopefully starting to appear in the near future.

The guys at Codehoop have done a great job! And here is a couple of movies they have put together to help users install the editor and view the OMG BPMN2 examples.

Note: the editor is based on Graphiti, which is only at version 0.7.1, and an early version of the Eclipse BPMN2 meta-model, so this is still a work in progress. So expect to find issues with any of the new technologies. However I would encourage you to download the editor and have a play.

The current editor provides the base level capabilities for creating a BPMN2 compliant model and diagram. However as with any new UI, there are areas where usability improvements would be required. This is work that will happen over the coming months, so feel free to express your views on how the use experience can be improved.

At the moment the issue reporting for the editor is through the jBPM project, using the 'Eclipse' component. However we are working towards moving this editor to Eclipse.org .... so watch this space.

Friday 11 February 2011

Savara goes TAPless

Before anyone gets too excited, let me explain.

Savara 1 recently introduced the concept of the Testable Architecture Project (TAP). This is an XML representation of (as the name suggests) a testable architecture project, defining the different artifacts associated with the stages of the software development lifecycle, and the dependencies between them.

Savara 1 has been primarily focused on the Eclipse environment, and therefore a mechanism was needed to define the artifact dependencies, so that the static validation between various artifacts could be triggered when a change occurred.

However we always had an eye on the future, and that Savara 1 should ideally be working with an SOA repository, and that Savara 2 would be more web centric than Eclipse based. So the problem the TAP was attempting to address was to enable dependencies to be represented when no repository was available.

The problem it introduced was how the dependencies in the TAP would be synchronized with the dependencies that may be defined when those artifacts were also stored in a repository. This was one of the main objections raised to the use of the TAP on the Savara forums, but at the time it was difficult to see how dependency information could be managed without being fully dependent upon the artifacts being stored in the repository - i.e. static validation would only occur when changes were made and committed back to the repository.

However now there may be light at the end of the tunnel. There have been discussions about the creation of a general purpose repository project, with profiles suitable for specific domains (e.g. rules and SOA). There is potential for the Savara project to feed in its requirements, and help contribute to this repository project, to find a solution that would work with and without a repository being available (i.e. online).

Watch this space ........