flow and db transaction?

vipi_voxa

Hello guys,

Please help me to get rid of my darkness. I am new to Activiti and BPMN and i am apologizing for this in advance. I have installed eclipse activiti designer, i have managed to get activiti-explorer 5.22 up & running on jboss together with activit-rest ,all works fine, db is oracle. But...

But ... I think i missing some crucial point in understanding of how to work with Activiti Bpmn. 

Let's keep it simple, lets say I have a process "A" which i designed in Eclipse Activiti Desiner and deployed to my Activiti instance running on my server.

Process "A" has an incoming parameter, lets call it "test_table_id". And the process at some point needs to update DB table. E.g. in my flow i need to execute "update test_table set processing_status='S' where test_table_id=${test_table_id}" as one of the steps.

Simple structure of the flow:

Process "A": starts -> UserTask to User "Mr.X"->"Mr. X" completes task-> Update DB table action -> Other actions ->ends

Sounds and looks easy - but how to implement correctly? First question: What type of activiti event is suitable for DB update call?

At the moment I have created groovy ScriptTask which is calling java code. This java code updates DB. It Works, but doesn't  look like a correct approach, because i am making, calling, committing and closing jdbc connection inside that java. But how to handle commits and rollbacks then afterwords in a flow? What if Other Actions fails? In my created diagram the task stays active if 'Other actions' failed, means user can complete task again and then update db action (which i implemented via scriptTask) is performed again.

Please fellows, advice me with best practice hints,

thank you!

gdharley

Hi Vipi, jus remember, Activiti is a general purpose workflow engine. People use it for high speed straight through processing, user based processes, data translation and mediation and god know how many other things. Think of it as a general purpose state machine with a visual state definition language.
Many processes have no need to updating external systems, and those that do, tend to use services to abstract the business logic from the crud or boiler plate code.

If you are looking for a general purpose SQL JavaDelegate, you can write one in < 20 lines of code using Springs JDBCTemplate classes (19. Data access with JDBC ). Setup inputs as the schema name, sql and list of parameters and transform the resultset into JSON and you have a simple general purpose service that you can throw anything at. IMO, this isnt a good approach as it puts CRUD logic into the business process, but it is an option if you are just trying to hack something together (can't say I havent use the approach).

Cheers,

Greg

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