Convert XML schema files to validating parser (Go source files) XML schema validation is a useful thing.
A schema description (xsd) defines a XML dialect, and a validating parser only accepts XML files that match the schema.
Example 3 - invalid XML (duplicated attribute): Such malformed XML files are accepted by the generated parsers, and all but one duplicate values are silently discarded.
In contrast to the sequence order weakness, this issue could be fixed in the native Go XML parser, because it simply is invalid XML.
Applications using XML content can rely on the constraints defined in the schema, saving a lot of error handling code without risk.
Go's XML parser (encoding/xml) is lazy in checking, but very performant.
(Even a DTD qualifies as a "schema", although it is the only one that does not use XML syntax to describe schema constraints.) However, "XML Schema" presents us with a terminology challenge.The second line specifies the schema to use for elements in the document that do not have a namespace prefix -- that is, for the elements you typically define in any simple, uncomplicated XML document.Note: You'll be learning about namespaces in Using Namespaces.To complement this parser by schema validation, we could wrap existing validating parsers (e.g.Apache XERCES-C but would then face a huge interface at the risk of performance loss.(I will provide detailed installation notes how to compile and install Xalan correctly on Ubuntu 15.04.) After cloning the project, cd into it.The following make commands are available: -test.xml) that lists test files together with their expected parse result.In order to perform schema validation, additional constraint checks ensure that values are in the predefined range or strings match regular expressions.The technique used is XSLT (XML stylesheet processing) using Apache's Xalan stylesheet processor. Ubuntu 15.04) the stylesheet processor is broken or comes with the wrong version.In addition to the error handling you've already learned about, there is one error that can occur when you are configuring the parser for schema-based validation.If the parser is not 1.2 compliant, and therefore does not support XML Schema, it could throw a The first attribute defines the XML Name Space (xmlns) prefix, "xsi", where "xsi" stands for "XML Schema Instance".