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Oracle BPEL - experience as a workflow engine

It all started one day when I received a link to Oracle BPEL and instructed to investigate it. For those who do not know, BPEL is a language for describing business processes, Oracle BPEL is, among other things, also a workflow engine. Everything started well, the installation went smoothly, everything seemed to start, but one function was missing, without which it is simply impossible to live.

Rummaging through the forums, I found that the patch to our version will save us. The patch was placed strangely, some folders were described in the patch installation documentation, which I simply did not have. What's the f ** ck? After a long dance with a tambourine, for some reason, the idea came to me to go back to the site with the files to download. For me it was a revelation that initially I put the wrong thing. It was necessary to download a file with a similar long name, but without the word BPEL, i.e. solve the problem by contradiction.

This thing was simply called SOA - Service Oriented Application, it contained BPEL and even something else (I installed SOA BPEL before). Having installed a new product and patch, I was delighted to see the homepage in the browser. But it was not there. Tasks after launch disappeared somewhere. Poking the mouse back and forth and found them, but nothing could be done with them.
Depressed again, he began dancing with a tambourine and found a curse on the NLS - National Language Settings. I tried to make the system forget about Russian forever, but it didn’t want, Russian roots made themselves felt. I had to install the English version of windows. As I expected, it helped, but not to the end. For some reason, the system cursed the lack of memory, although there was enough memory. I had to allow more memory.

After these ordeals, Oracle BPEL began to work. Think this is the end? Not at all. Then there were problems with the API. Very poor documentation makes you refer to the Oracle forum for finding the right information. Often I ran into similar problems that I had and often there was no answer.

What can you say about Oracle BPEL, if it does work for you as needed? This is the language for real programmers. You need to know XPath, and understand the challenges of web services. You can not make arbitrary transitions between tasks. Apparently BPEL was written by people who are very fond of structured programming and hate the GOTO operator. And normal workflow just should have cunning transitions like goto.

In BPEL, you have to do a lot to do simple things. BPEL was originally created as a language for working with services and does not fit well with the role of the workflow engine. For some reason, the authors of BPEL made it so that with any error the whole process falls. And in real life, business processes can last for months and restore the process to its former state - a difficult task. With such errors, it would be logical to stop at the problem step in order to be able to correct the error without restarting the process.

In addition, the system as a whole is unstable and in the course of work errors are detected, which are solved by restarting or reinstalling. Perhaps this was due to the fact that I used Oracle Express Edition instead of the usual Oracle Server.
I also forgot to say that it is possible to install Oracle Lite, but the patched BPEL doesn't work with it at all.

When working were used version:
Oracle SOA Suite 10g, patch
Oracle Express Edition

All success in learning Oracle.

Source: https://habr.com/ru/post/102486/

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