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Friday, July 29, 2016

Learner Series: Handling Dynamic Array in BPEL 2.0

Dynamic arrays are always tricky to handle within a BPEL process. Every now and then we encounter XML schemas that have generic name-value pair arrays that are unbounded. The challenge is assigning data to and from these dynamic arrays as there are no concrete XML target elements at runtime. Hence, the XML elements must be generated first before assigning values to them.

There are multiple ways this problem can be solved.

For one, you can choose XSLT over a simple assign. XSLT wields more granular control over how the XML elements are handled. You can instruct the XSL processor to loop over dynamic array list and assign values. This of course requires some level of XSLT skill (Although JDeveloper presents an easy XSL mapper, I prefer fiddling with the source) and in certain cases, you may have to pass some BPEL variables (properties) to XSLT in additions to the source and target variables.

Second option would be to use an XML literal (called XML fragment in BPEL 1.1) within your assign activity. Here you can pre-form the XML literal, assign it to the target and then map the values. Not so sophisticated and if you are not careful with namespaces, this could cause a lot of mapping troubles.

Thirdly, with BPEL 2.0 you can simply add an attribute to your copy action in your assign activity to achieve the same. Most simplest of all.

Since this is a learner series, let's get into some details on how to go about this;

Let's first understand the root-cause of the error;

The problem with assigning dynamic arrays within BPEL is that, for the first element in the array, since the XML element is always "available", the copy happens successfully.
However, starting with the second element, all copy rules within assign would fail due to a "selection failure" with the following error because the dynamic array XML elements are still not formed or is empty.

"Exception is thrown because the to-spec at line 140 is evaluated to be empty"
or
"Exception is thrown because the from-spec at line 160 is evaluated to be empty"

depending on whether you are trying to copy to a target or copy from a source.

Your XML schema containing dynamic array may look something like this;



Your typical assign would like the following - you will have to manually let BPEL know which element the values must be mapped - [1], [2], [3] .... [n]. Just append this to your root XML element which contains the dynamic array. In this case;



Now, starting with the second copy rule within your assign, right-click on the rule item and select "ignoreMissingFromData" or "insertMissingToData" depending on whether your dynamic array is being read or written to respectively.



This action would add a flag (attribute) to the copy rule instructing BPEL to handle the dynamic XML element - either ignore or insert.

<copy bpelx:insertMissingToData="yes">
or
<copy bpelx:ignoreMissingFromData="yes">

Happy BPELing...

Saturday, June 11, 2016

Java Node.JS Microservices Hackathon, Boston

Let's Hack !! 

Join us for the Boston microservices hackathon and learn about latest Java 8, JET and Node.JS.

We will also go cloud native to create, build, deploy and manage microservices on Oracle Public Cloud. 

Space is limited. Register early @ https://lnkd.in/eF2XrfK

Or post your contact in the comments and I will register you.

See you there !! 

Tuesday, September 29, 2015

SOA 12c Compact Domain DB Based MDS

With the release of SOA 12c, developers can now have full-fledged SOA 12c running on their desktops/laptops on the integrated WebLogic server. This is a great news for development community - as one can download the SOA/BPM 12c quickstart which comes pre-configured with JDeveloper and integrated WLS running SOA/BPM.

Some developer productivity benefits include;
1) You don't need a license for quickstart installs (for development & evaluation purposes)
2) Single jar that will install & configure WebLogic domain, SOA, JDev and everything you need to get going

However, there are some limitations with the default quickstart install. For one, the quickstart installation runs on top of Java Derby DB; and the SOA MDS is a file-based repository by default. Although for normal development purposes this may not be a big challenge, it could be an issue if you want to leverage some features such as;

1) Run-time modification of business rules
2) B2B, MFT & ESS
3) SOA Composer
4) BAM
5) BPM Composer etc.. which require a Oracle database to run.

However, there are other ways to configure your development environment to run on top of Oracle database - therefore you can have a DB based SOA MDS.

In this post, I will illustrate how to install and configure a SOA 12c compact domain for development purposes.

Pre-Requisites:

1) Download Java 7. According to the certification matrix jdk 1.7.0u55+ is supported - here
2) Download Oracle XE 11g Database - here
3) Download SOA 12.1.3 quickstart distribution - here
4) Optional components such as B2B, MFT, can be downloaded if required
Download MFT - here
Download B2B - here

Install java 7 on your environment. Note: By default on windows jdk will choose a location under "Program Files". In certain cases, I have seen the space in folder location cause unknown issues. Ensure java is installed on a location without space in the folder name eg., C:\Java

SOA 12c Quickstart Installation:

Unzip the fmw_12.1.3.0.0_soaqs_Disk1_1of1.zip

Open terminal (command prompt) as administrator
Ensure JAVA_HOME and PATH environment variables are set and points to the jdk installed
set JAVA_HOME=C:\Java\jdk1.7.0_71
set PATH=%PATH%;C:\Java\jdk1.7.0_71\bin

Step 1:
Execute the following command to install the SOA 12c quickstart
java -D64 -jar fmw_12.1.3.0.0_soa_quickstart.jar
Step 2: Provide a oracle home where SOA 12c must be installed
Step 3: Ensure the validations are okay
Step 4: Review the installation summary - provides the list of features/components installed as part of the quickstart distribution
Step 5: Review the installation progress
Step 6: Once the installation succeeds, click Finish.
At this stage, quickstart can be used if you are not looking for features such as mentioned above. Just open the JDeveloper, right click on the IntegratedWeblogicServer to create and start domain. JDeveloper takes care of creating a WLS domain and configuring it automatically.

Follow through for a compact domain installation.

If you need additional components such as B2B, BPM or MFT now is the time to install them. Let's install B2B.

Installing Oracle B2B:

Step 1:
Unzip fmw_12.1.3.0.0_b2b_Disk1_1of1.zip and execute the following command to install B2B
java -D64 -jar fmw_12.1.3.0.0_b2bhealthcare.jar
Step 2: Choose the same Oracle home that was used to install the SOA 12c quickstart
Step 3: Choose B2B or Healthcare profiles depending on requirement. Let's choose B2B
Step 4: Follow the instructions and click Finish to close the B2B installation wizard
 

I haven't detailed the MFT installation. However, should you need, it is a very straightforward installation.

Installing XE 11g Database:

Unzip the OracleXE112_Win64.zip and follow the instructions to install XE database.

Step 1: Execute setup.exe
 Step 2: Accept the license agreement
Step 3: Choose the destination folder where XE must be installed
Step 4: Enter the SYS password
Step 5: Review and click Install
Step 6: Click Finish to finish the database installation

Creating RCU schemas for compact domain:

Step 1: Execute rcu.bat from the following location - $ORACLE_HOME\oracle_common\bin


Step 2: Leave the default selection on Create Repository and click Next
Step 3: Provide the database connect information and click next
Step 4: Ignore the warning. XE is not a "certified" database but will work fine in development environments.
Step 5: Default prefix is DEV. You can change this if you need. Select the SOA Infrastructure schema from the list which will select the required schemas
Step 6: Provide a password that will be used for all the RCU schemas
Step 7: Here you can select the size for the database profile. Default is small and should be fine for development environments. Optionally you can choose to enable/disable healthcare integration
Step 8: Follow the instructions and proceed with creation of database schemas for our compact FMW domain. Click close in the final summary screen.

Create and Configure Compact SOA Domain:

In this section let's create and configure a compact SOA domain.

To enable compact domain option, set the following environment variable before executing the config.cmd script

> set CONFIG_JVM_ARGS=-Dcom.oracle.cie.config.showProfile=true
> cd $ORACLE_HOME\oracle_common\common\bin
> config.cmd

Step 1: Choose the "Create a new compact domain" option and provide a domain name/location
Step 2: This is an important step where you must choose the templates with which the compact domain will be created. Choose all the required components. Note that the templates would show up based on the installations in the current domain.
Step 3: Choose a folder location where applications would reside
Step 4: Provide a administrator username and password.
Step 5: Choose Development mode / Production Mode (basically if you choose production mode, you will be prompted for the administrator username and password every time you start the weblogic server). Choose the JDK that we installed earlier which will be picked up by default.
Step 6:Provide the database details and click Get RCU Configuration. Once you get a success message proceed to next step.
Step 7: In the JDBC component schema page, select all the schema components and click next
Step 8: A test would run against the database for the schema connectivity. Once you get a success for all the components proceed further.
Step 9: For a compact domain with a "Admin" only server which will host all the middleware services leave the defaults on step 9 and click next. If you have a need to update the configuration such as adding managed servers, update default ports you can check the appropriate configuration and update.
Step 10: Click Create to create a compact SOA domain
Step 11: Ensure the domain creation succeeds and click Finish to close the config wizard.


That completes the creation of a SOA compact domain.

Now, if you start the weblogic server by issuing startWebLogic.cmd command, you will notice that the Java DB instance would start automatically. Since this is a compact domain and it will run off the Oracle XE database instance, we don't need the Java DB.

Start the weblogic with the noderby flag to prevent the Java DB from starting up.

> cd $ORACLE_HOME\user_projects\domains\compact_domain\bin
> startWebLogic.cmd noderby

Once the server starts up, establish connectivity to all the services to test the installation;

WLS Console: http://localhost:7001/console
EM Console: http://localhost:7001/em
SOA Composer: http://localhost:7001/soa/composer
B2B Console (if installed): http://localhost:7001/b2bconsole
BAM Console: http://localhost:7001/bam/console

One advantage with compact domain is that you can also create a integrated weblogic domain from JDeveloper which could be handy for a lot of development activities.

Wednesday, September 16, 2015

Are we ready for the cloud leap?

Cloud computing has come a long way from just being a buzz word. With the burgeoning of cloud companies and service providers across the planet, are we ready for the cloud leap yet?
Let’s reflect on a life-changing innovation that happened in the last decade – the evolution of smart phones. One can monitor health, pay utility bills, transfer funds, call a taxi and post an fb update on-the-go and in seconds. From just being a consumer focused platform that brought everything to our palms, it has matured into a first-class citizen of most enterprises today. It is hard to imagine appliction architectures today without a mobile strategy. Almost all customers I work with has a mobile strategy – at least in principle – and are getting their key end-user focused functions on mobile to keep pace with competition, if not outpace them. For instance, it is impossible for a bank to thrive in today’s aggressive environment without a mobile app that supports ‘Check Deposits’. Trendsetters like Uber, Instagram, Myntra, Hotel Tonight went mobile only strategizing their business model to consumer demand. That was the revolution of the last decade.
Is cloud the next big thing? ......

Tuesday, February 17, 2015

Integrate OSB with Oracle MFT

Recently, I had an opportunity to work with a customer on MFT integration with OSB.

Some pain points were;
1) Ever-increasing FTP servers across their enterprise which was increasingly becoming tough to manage and maintain.
2) Custom code for compression/decompression logic before/after file transfers
3) Bunch of third-party utilities for scheduling file transfers
4) Java code exposed as API for PGP encryption/decryption

Obviously they had a lot of integration touch-points while putting together a file transfer solution - which also meant multiple points of failure and not to mention the maintenance/debugging nightmare if something were to go wrong.

One of the cool features of Oracle MFT is that it supports out-of-the-box integration with many technologies including OSB. For many OSB users, the following could be some of the use-cases where they could take advantage of MFT and reap benefits;

Traditional OSB implementations used File/FTP adapters for file transfers - No real visibility into the transfers and not the best of designs to manage/maintain.

With Oracle MFT exposed as a webservice it is now just a seamless webservice invocation - with the added benefits such as real-time visibility, OOTB scheduling, Compression, PGP encryption, ease of maintenance to name a few..

Use-Case 1: OSB triggers a MFT transfer

In this use-case OSB would trigger a MFT transfer. MFT would then fan-out the transfer;
a) Decompress, Decrypt and store in file system
b) Initiate a SOA process to do further processing (human task etc..)



Creating a MFT Source:

Step 1: Login to Oracle MFT console (http://hostname:port/mftconsole)

Step 2: Go to the Design tab. Click on the Sources and create a new OSB source as shown below;


Creating a MFT Target:

Step 3: Now, click on the Targets and create a new MFT target (This can be a webservice, SOA service, FTP, sFTP, File etc..).
In this case, we would be creating 2 targets - one SOA target and a File target as shown below;

Note: For the SOA target - I just created a simple SOA composite with MFT adapter...



Now. let's create a Transfer - nothing more than linking the source & target on a canvas.

Step 4: Click on the Transfers and create a new MFT. In the MFT canvas, drag and drop the OSBSrc to the source panel. Similarly, drag and drop the OrderSOATarget & PutFile targets to the target panel. Note that "decompress" and "decrypt" pre-processing actions are added to the targets. These are out-of-the-box capabilities that you can leverage with Oracle MFT.



That's all. Now just define a business service in OSB as usual that will trigger the transfer in Oracle MFT. You can obtain the MFT (OSBSrc) source webservice URL by just opening the source.




Use-Case 2: Oracle MFT invokes OSB proxy service

Here we will pick a file from the embedded FTP server (FTP & sFTP servers are embedded and comes out-of-the-box with Oracle MFT), and invoke a OSB target.

Step 1: Click on Sources and create a new source of type "FTP Embedded" as shown below;

Step 2: Click on Targets and create a new target of type "OSB" as shown below

Step 3: Click on the Transfers and create a new MFT. In the MFT canvas, drag and drop the FileSrc to the source panel. Similarly, drag and drop the OSBTgt to the target panel

Done. Now, let's see how to create a OSB proxy service that will consume the MFT transfer.

Step 4: Login to OSB console. Create a proxy service based on the WSDL available @ $FMW_Home/mft/integration/wsdl/MFTSOAService.wsdl (While source/target type is chosen as OSB or SOA, MFT exposes the web service based on this WSDL contract)

Note: Ensure that the proxy service URL and the MFT OSBTgt URL matches.

As easy as that.