How can we use "try-catch" with Wrapped meta node?

Hi,i can use "try-catch" with a meta-node,and they worked well.But,when i wraped this meta-node,"try-catch" framework cannot work anymore.

Is there any way to solve this problem,or any replacement solution? 

thank you.

Hi Loongel,

could you post me your workflow?

Thank you! Iris

I am attaching the snapshot below for your reference. 

thank you.

I’m just facing the same issue. For testing purposes I prepared a logic that asserts that number of rows of a table is as expected. I introduced Fail in Execution node from KNIME Testing Framework putting it to a conditional branch which is active when actual number of rows differs from an expectation. If I surround the logic with Try (Data Ports) and Catch Errors (Data Ports) pair of nodes it works as I expected but after I encapsulate the nodes between Try and Catch nodes (without the Try and Catch nodes themselves) into a Wrapped Metanode it stops working that way. In the negative test scenario case, the flow gets stuck in Fail in Execution node and everything after this node including WrappedNode Output remains in yellow state.

The same case expanded - and working:

Hi Jan,

right now only non wrapped nodes can be used in a try-catch construct. Sorry about this.

Best, Iris

I stumbled around the same problem. Is there any plan to change this? It kills a lot of my try-catch constructs…

Hi there @Lukasa ,

I will add +1 for it.


Is there a plan to get this fixed? Maybe in KNIME 4.1 to be released in December 2019? It is really unexpected that this is not working the same for metanode vs. wrapped metanodes.


Just to add info that Components (previously called Wrapped Metanodes) can now be used with Try/Catch nodes. Works both in versions 4.1.4 and 4.2.


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