Error handling in Composer

[peters]

I'm trying to find the best way how to handle unexpected errors in GVP8 Composer voice application. The callflow is: URS -> GVP8 -> URS -> agent.

In the composer project, web service is called and JSON object returned.

AppState.object = {property1:value1, property2:value2}

Parsing done in assign block:

AppState.variable1 = AppState.object.property1
AppState.variable2 = AppState.object.property2

In the following branching block, AppState.variable2 is compared to a value. Here i get semantic error, in case of missing property2:value2 inside of object.

A this point, the call is dropped and not being passed to URS.
What are the best practices for error handling here?

Support already recommended not to use error:all -> Transfer (back to URS). In case of hangup, call should be dropped (transfer block caused loops, because the interaction data can't be passed to SIPserver, if the call does not exists).

Thanks,
Peter