> > Schematron is really only needed for really rich validation rules that use > the tree-walking capabilities of XPath to scrutinize elements wherever they > appear in the infoset tree. >
I'll give it a try with dfdl:assert and see how it goes. Thank for all the feedback! Claude On Mon, Jul 24, 2023 at 11:35 PM Mike Beckerle <mbecke...@apache.org> wrote: > Something to consider: > > I think many useful validation checks can be expressed in DFDL's > expression language using the dfdl:assert statement with > failureType='recoverableError'. > > The sort of constraints that say if this element exists then that can't > exist, or if this has a specific value that that must exist... those sorts > of things can usually be expressed. > > Those are run in an incremental/streaming fashion as the parser traverses > the data based on the schema. > > Recoverable errors from Daffodil are the same as validation errors from > Daffodil's internal "limited" evaluation. They don't guide the parse (don't > cause backtracking), but come out as diagnostic warnings. > > Schematron is really only needed for really rich validation rules that use > the tree-walking capabilities of XPath to scrutinize elements wherever they > appear in the infoset tree. > > > > > > On Mon, Jul 24, 2023 at 7:47 AM Steve Lawrence <slawre...@apache.org> > wrote: > >> This is correct. The way daffodil currently implements full validation >> (xerces) and custom validation (e.g. schematron) is pretty inefficient. >> We create two infosets: one the kind that the user passed to the parse >> function, and one that is text XML written to a ByteArrayOuputStream in >> memory that is used internally for the validation once the parse is >> completed. We do not currently stream validation. >> >> If you wanted streaming, you would probably need to create custom >> InfosetOutputter, or maybe use the SAXInfosetOutputter with an XMLReader >> that chains/tees SAX events to custom schematron validation. >> >> - Steve >> >> On 2023-07-22 03:29 AM, Claude Mamo wrote: >> > Spotted this code so presumably it's not streaming when custom or full >> > validation is in force: >> > >> https://github.com/apache/daffodil/blob/main/daffodil-runtime1/src/main/scala/org/apache/daffodil/runtime1/processors/DataProcessor.scala#L345-L356 >> < >> https://github.com/apache/daffodil/blob/main/daffodil-runtime1/src/main/scala/org/apache/daffodil/runtime1/processors/DataProcessor.scala#L345-L356 >> > >> > >> > Claude >> > >> > On Sat, Jul 22, 2023 at 8:07 AM Claude Mamo <claude.m...@gmail.com >> > <mailto:claude.m...@gmail.com>> wrote: >> > >> > Hello Daffodil team, >> > >> > I'm looking into adding support for Schematron validation since we >> > have had many Smooks developers asking for better validation of >> > EDIFACT documents. One question I have is whether Schematron >> > validation is applied in a streaming fashion. I mean, does Daffodil >> > load the whole infoset into memory before applying the Schematron >> > rules or is Schematron validating on the fly while accumulating any >> > state that is required to be able to evaluate the rules? >> > >> > Thanks, >> > >> > Claude >> > >> >>
