olabusayoT commented on a change in pull request #273: WIP: Add User Defined Functions Capability URL: https://github.com/apache/incubator-daffodil/pull/273#discussion_r336721059
########## File path: daffodil-runtime1/src/main/scala/org/apache/daffodil/dpath/UserDefinedFunctionBase.scala ########## @@ -0,0 +1,35 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +package org.apache.daffodil.dpath + +import org.apache.daffodil.exceptions.Assert +import java.lang.reflect.Method +import org.apache.daffodil.udf.UserDefinedFunction + +/** + * Both the evaluate method and the User Defined Function instance are passed in, as both are needed by the Method.invoke + * function. + */ +case class UserDefinedFunctionCall(recipes: List[CompiledDPath], userDefinedFunction: UserDefinedFunction, evaluateFxn: Method) + extends FNArgsList(recipes) { + override def computeValue(values: List[Any], dstate: DState) = { + val jValues = values.map { _.asInstanceOf[Object] } + val res = evaluateFxn.invoke(userDefinedFunction, jValues: _*) Review comment: So the current error handling is as follows: For the case where an Exception is thrown during the evaluate call. (It gets captured by the Reflection class and comes out as a ReflectiveOperationException), we throw a processing error as our current expectation is not for the UDFs to be throwing errors. (I can see why we would want to change this, but more on that below) All other exceptions thrown from UDFP load time till UDF initialization time, are caught and output as log errors/warnings. Because we can either not load any UDFs or drop the offender, and throw an SDE for unsupported function. So the idea posited would mean we throw an SDE if we receive a UDFException from the UDF. As this would be them signalling that they received some data (or something) they considered invalid, so it wouldn't actually be a processing error, but instead a signal to Daffodil that something was wrong with the received parameters? That makes sense. I'll implement. Re the backtrace, would it be preferable over something like the below? `[error] Error loading User Defined Function Providers: Error thrown in: org.sgoodudfs.example.StringFunctions.StringFunctionsProvider$CustomException: UDF Error!` ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services
