re: Design-for-Test for UDF facility
When this code gets to code review with tests one of the key things will be that we get decent diagnostics from this for all the things users can do wrong in creating the UDF jar, such as not having it be found, not having all the classes in it, not having them named right or derived properly, etc. etc. First cut is errors should be throwing a Daffodil-defined exception object, which encapsulates whatever exception object the actual underlying UDF reflection code or Service API call throws. Regression testing this UDF facility will require some trickery, as some tests will not be ordinary JUnit-style tests, as incorrectly-constructed jars have to be created and used. I recommend that we add some "official" UDFs to daffodil that are always part of the standard build, not because they are useful, but because they allow us to test the UDF system. An important test case is also to define such a UDF which throws an exception, so that we can have tests that verify the exception is properly caught and reported. ________________________________ From: Kilo, Olabusayo <ok...@tresys.com> Sent: Friday, September 6, 2019 10:30 AM To: dev@daffodil.apache.org <dev@daffodil.apache.org> Subject: [DISCUSS] User Defined Functions Capability I'm requesting a discussion on the addition of the User Defined Functions capability to daffodil. The proposal referenced below provides a possible solution for Daffodil to be able to process and use User Defined Functions referenced in the DFDL Schema. The original request can be found at https://issues.apache.org/jira/browse/DAFFODIL-2186 and the proposal can be found https://cwiki.apache.org/confluence/display/DAFFODIL/Proposal%3A+User+Defined+Functions.
