Hi Alberto. Seems that the feature fgXercesCacheGrammarFromParse was the missing one in the feature list set in my getDOMBuilder() method to get the schema recognized for the xml parsing. Thanks much for that hint. It really does not seem obvious to me why this is needed as I even tried loadGrammar(..., ..., true) solely. Now both together work.
BTW: Maybe you have an explanation for the following, too: I have recognized that when additionally applying the feature fgXercesValidationErrorAsFatal my DOMErrorHandler instance will NOT be called for fatals but for errors when the xml is invalid against the schema. Any idea ? Kind regards. Frank -----Original Message----- From: Alberto Massari [mailto:[EMAIL PROTECTED] Sent: Donnerstag, 19. Mai 2005 21:54 To: [email protected] Subject: Re: Failure to assign/relate an in-memory schema to an in-memory xml Hi Frank, whenever I need to validate an XML file against a schema, and the XML doesn't have a reference to that schema, I do the following: - create a parser - call useCachedGrammarInParse(true) or setFeature(fgXercesCacheGrammarFromParse, true) - call loadGrammar(MemBufInputSource, Grammar::SchemaGrammarType, true) [the last argument tells the parser to cache the grammar) - call setDoValidation(true), setValidationScheme(Val_Always), setDoNamespaces(true) - call parse(MemBufInputSource) to load the XML Hope this helps, Alberto At 17.45 18/05/2005 +0200, Gierschner, Frank wrote: >Hi all. > >I have some experience with XML in general but I am new to Xerces, so >please provide some hints. > >I wish to schema-validate an in-memory xml-string, coming in from a CORBA >client, against an in-memory schema. But the parser (DOMBuilder) does not >seem to associate the xml-data with the provided schema. I provide both >from within MemBufInputSource and I am unaware of the real functionalty of >the so-called 'fake system id'(argument 3: bufId) and if it has something >to do with the failure. > >I even considered to write the schema temporarily to a xsd-file, build a >DOM from the incoming xml-string, adding a schemaLocation attribute to the >still unvalidated DOM, serializing this DOM into a new string and the >reparsing and validating against the xsd-file but that seems error-prone, >cumbersome and does not work yet, too. > >I provided some test results I encountered when dealing with files and the >interesting part of the code below. > >I would appreciate your help. > Thanks in advance. > Frank Gierschner > > >// small excerpt on dealing with files now >In order to get track of the problem I modified the SCMPrint example >around line 335 to be: ><code> > parser->loadGrammar(xsdFile, Grammar::SchemaGrammarType, true); > if (handler.getSawErrors()) > { > handler.resetErrors(); > } > else > { > parsedOneSchemaOkay = true; > } > > parser->parse(xmlFile); // NEW ></code> >where xmlFile denotes a file which is a XML-Document having a >schemaLocation attribute directing to xsdFile. If in this case xmlFile >contains an invalid document the previously applied ErrorHandler will see >fatal errors - that is correct. But when I remove the schemaLocation >attribute from xmlFile the same procedure results in errors like 'unknown >element ...' which reveal that xml-data and schema seem to be unrelated. I >guess the latter is the same problem occuring with the above stated >in-memory procedure. >// end of excerpt > > >The interesting part of the code I use for the in-memory variant looks >somewhat like the following: > ><code> >// the in memory schema >static const char gMySchema[] = >"<?xml version=\"1.0\" encoding=\"utf-8\" ?> \ ><xs:schema xmlns:xs=\"http://www.w3.org/2001/XMLSchema\"; >targetNamespace=\"urn:rtc:tgam:MNCfgTmpl\" \ >elementFormDefault=\"qualified\" attributeFormDefault=\"unqualified\"> \ ><xs:element name=\"root\"> \ ><xs:complexType> \ ><xs:sequence> \ ><xs:element name=\"FirstElement\" type=\"xs:string\" /> \ ><xs:element name=\"SecondElement\" minOccurs=\"0\" type=\"xs:string\" /> \ ><xs:element name=\"ShirdElement\" type=\"xs:string\" /> \ ></xs:sequence> \ ></xs:complexType> \ ></xs:element> \ ></xs:schema> \ >"; > >... -- omitted other stuff -- > >static DOMBuilder * getDOMBuilder(MyDOMErrorHandler *& myErrorHandler, >const char pSchema2use[], Grammar *& grammar) >{ > DOMImplementation *impl = > DOMImplementationRegistry::getDOMImplementation(L"LS"); > DOMBuilder* theBuilder = > ((DOMImplementationLS*)impl)->createDOMBuilder(DOMImplementationLS::MODE_SYNCHRONOUS, > > L"http://www.w3.org/2001/XMLSchema";); > > if (theBuilder->canSetFeature(XMLUni::fgDOMNamespaces, true)) > theBuilder->setFeature(XMLUni::fgDOMNamespaces, true); > > if (theBuilder->canSetFeature(XMLUni::fgDOMValidation, true)) > theBuilder->setFeature(XMLUni::fgDOMValidation, true); > > if (theBuilder->canSetFeature(XMLUni::fgDOMDatatypeNormalization, true)) > theBuilder->setFeature(XMLUni::fgDOMDatatypeNormalization, true); > > if (theBuilder->canSetFeature(XMLUni::fgXercesSchemaFullChecking, true)) > theBuilder->setFeature(XMLUni::fgXercesSchemaFullChecking, true); > > myErrorHandler = new MyDOMErrorHandler(); > theBuilder->setErrorHandler(myErrorHandler); > > if (pSchema2use) > { > grammar = NULL; > MemBufInputSource *myXSDInputSource = new MemBufInputSource((const > XMLByte *const)gMySchema, (unsigned int) strlen(gMySchema), > L"http://www.w3.org/2001/XMLSchema";, false); // unaware about > functionality of argument 3 > Wrapper4InputSource wrapper(myXSDInputSource); // will adopt > myXSDInputSource > grammar = theBuilder->loadGrammar(wrapper, > Grammar::SchemaGrammarType); > } > > return theBuilder; >} > >... -- omitted other stuff -- > >static int buildDOMDocument(const XMLByte* const buf, const unsigned int >uiSize, DOMDocument* &doc) >{ > DOMBuilder* theBuilder = NULL; > MyDOMErrorHandler* myErrorHandler = NULL; > Grammar *grammar = NULL; > theBuilder = getDOMBuilder(myErrorHandler, gMySchema, grammar); // see > above > > > MemBufInputSource *myInputSource = new MemBufInputSource(buf, uiSize, > L"TEST", false); // unaware about functionality of argument 3 > > Wrapper4InputSource wrapper(myInputSource); // will adopt myInputSource > > int retVal = -1; > try > { > DOMDocument* newDoc = theBuilder->parse(wrapper); > retVal = (myErrorHandler->sawFatals() ? -9 : > (myErrorHandler->sawErrors() ? -5 : 0)); > > if (newDoc) > doc = (DOMDocument*) newDoc->cloneNode(true); > } > catch (const XMLException& toCatch) > { > cout << "Exception message is: \n" << X2c(toCatch.getMessage()) << > "\n"; > } > catch (const DOMException& toCatch) > { > cout << "Exception message is: \n" << X2c(toCatch.msg) << "\n"; > } > catch (...) > { > cout << "Unexpected Exception \n" ; > } > > theBuilder->release(); > > delete myErrorHandler; > > return retVal; >} > >// the in-memory xml created previously via ... > ... > DOMImplementation* impl = > DOMImplementationRegistry::getDOMImplementation(L"Range"); > DOMDocumentType* doctyp= 0; // impl->createDocumentType(L"root", > NULL, L"TEST"); > DOMDocument* doc = impl->createDocument(L"urn:rtc:tgam:MNCfgTmpl", > L"root", doctyp); > doc->setEncoding(L"UTF-8"); > // > doc->setDocumentURI(L"http://www.w3.org/2001/XMLSchema-instance";);// > xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"; ??? > DOMElement* root = doc->getDocumentElement(); > ... >// ... and generated via serialization by DOMWriter::writeNode() from this >DOMDocument (from an example) looks like this > ><?xml version="1.0" encoding="UTF-8" standalone="no" ?> ><root xmlns="urn:rtc:tgam:MNCfgTmpl"> > <FirstElement>aTextNode</FirstElement> > <ThirdElement>aTextNode2</ThirdElement> ></root> > ></code>
