Q:

How To Test Talend ETL

I would like to know how it is possible to perform unit tests on the ETL developed on Talend.
My ETLs performs files reading, files generation,  and connection with SAP system. (read/write IDOC).
Is there any tools? Is what it takes to develop a small java Test Framework?

A:

Yes, Mohcine, Talend introduced in version 6 test case automation which is part of its overall Continuous Integration framework.  You right click on a component in a job and select  "Create Test Case".  It will create a skeleton test case job.  You can extend this test case job to perform a variety of tests, including db connectivity and results.   It will take some to learn the tool to make it useful, but worth the effort.  Also, this feature may only be available in the subscription version of Talend, I am not sure if its available in Open Studio.    
Here is an example:  diagram is a very simple job that loads a file into a db table.

Here is the test case I created by first generating the skeleton, then modifying it for my specific purposes. 

Here is the assert where I match the number of rows read from the file with the number of rows inserted into the db table.  

For further info check out this tutorial.  

