Does not support XSD 1.1

[bmix]

With a document instance, that is specced with XSD v1.1, I just got:

cos-all-limited.2: The {max occurs} of an element in an 'all' model group must be 0 or 1. The value 'unbounded' for element 'Bcc' is invalid.

However, when validating with Xerces2 I get no complaints. Could it be, that XSD 1.1 is not supported?

[fbricon]

@bmix do you mind providing some sample documents reproducing the issue?

[bmix]

Thank you, for investigation.

When I open the following XSD in the oXygen XML IDE, using Xerces2 (offending place highlighted in image):

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema 
	xmlns:xs="http://www.w3.org/2001/XMLSchema" 
	xmlns:t="test" 
	xmlns:vc="http://www.w3.org/2007/XMLSchema-versioning" 
	targetNamespace="test" 
	elementFormDefault="qualified" 
	vc:minVersion="1.1">
	
	<xs:complexType name="testType">
		<xs:all>
			<xs:element name="testEle" minOccurs="1" maxOccurs="unbounded" type="xs:string"/>
			<xs:element name="testEleTwo" type="xs:string"/>
		</xs:all>
	</xs:complexType>
	
	<xs:element name="testDoc">
		<xs:complexType>
			<xs:sequence>
				<xs:element name="testContainer" type="t:testType"/>
			</xs:sequence>
		</xs:complexType>
	</xs:element>
</xs:schema>

I get no problem shown. As soon, however, I remove the vc:minVersion="1.1" attribute (still in oXygen), effectively making it a 1.0 XSD, I get a:

The {max occurs} of an element in an 'all' model group must be 0 or 1. The value 'unbounded' for element 'testEle' is invalid.

This makes me conclude, that the error is bound to differences between 1.0 and 1.1 of XSD, as also indicated by this answer on Stack Overflow:

In XSD 1.0, the children of xs:all must have maxOccurs set to 1.

In XSD 1.1 this constraint is lifted.

When using the same data in VCode with Red Hat's XML Tools for this XML instance document (instance1.xml):

<?xml version="1.0" encoding="UTF-8"?>
<t:testDoc xmlns:t="test"
 xmlns:vc="http://www.w3.org/2007/XMLSchema-versioning"
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xsi:schemaLocation="test file:/path/to/issue.xsd">
	<t:testContainer>
		<t:testEle>testEle0</t:testEle>
		<t:testEle>testEle1</t:testEle>
		<t:testEle>testEle2</t:testEle>
		<t:testEleTwo>testEleTwo0</t:testEleTwo>
	</t:testContainer>
</t:testDoc>

I get these two errors in VCode:

{
	"resource": "/path/to/instance1.xml",
	"owner": "_generated_diagnostic_collection_name_#1",
	"code": "cvc-complex-type.2.4.a",
	"severity": 8,
	"message": "Invalid element name:\n - testEle\n\nOne of the following is expected:\n - testEleTwo\n\nError indicated by:\n {test}\nwith code:",
	"source": "xml",
	"startLineNumber": 8,
	"startColumn": 4,
	"endLineNumber": 8,
	"endColumn": 13
}
{
	"resource": "path/to/instance1.xml",
	"owner": "_generated_diagnostic_collection_name_#1",
	"code": "cos-all-limited.2",
	"severity": 8,
	"message": "cos-all-limited.2: The {max occurs} of an element in an 'all' model group must be 0 or 1. The value 'unbounded' for element 'testEle' is invalid.",
	"source": "xml",
	"startLineNumber": 11,
	"startColumn": 11,
	"endLineNumber": 11,
	"endColumn": 11
}

[NikolasKomonen]

I've looked into it and at the moment we don't support validation for XSD 1.1

Here are some references for when it is eventually worked on:

http://www.herongyang.com/XSD/Xerces2-Xsd11SchemaValidator-XSD-1-1-Validation.html
https://xerces.apache.org/xerces2-j/faq-xs.html

[angelozerr]

AFter reading the great article https://blog.adamretter.org.uk/xerces-xsd11-maven/ the problem comes from the official xerces maven 2.12.0 which doesn't provide xsd1.1 although documentation says that 2.12.0 support xsd1.1 (see article for more explanation).

To fix the problem, we must switch from the official xerces maven 2.12.0 to org.exist-db.thirdparty.xerces. In other words replace https://github.com/angelozerr/lsp4xml/blob/master/org.eclipse.lsp4xml/pom.xml#L99 with

<dependency>
    <groupId>org.exist-db.thirdparty.xerces</groupId>
    <artifactId>xercesImpl</artifactId>
    <version>2.12.0</version>
    <classifier>xml-schema-1.1</classifier>
</dependency>

After this dependency change, the error with cos-all-limited.2 disappears with:

<xs:schema 
	xmlns:xs="http://www.w3.org/2001/XMLSchema" 
	xmlns:t="test" 
	xmlns:vc="http://www.w3.org/2007/XMLSchema-versioning" 
	targetNamespace="test" 
	elementFormDefault="qualified" 
	vc:minVersion="1.1">

If I change vc:minVersion to vc:minVersion="1.0", the error appears again.

@fbricon do you think we should change the xerces dependency? My fear is about IP Process for Eclipse.

[NikolasKomonen]

@angelozerr @fbricon I'm trying this out and the tests fail with some OutOfMemory Java heap space errors.

I've tried in the root pom file to put something similar to:

<plugin>
    <configuration>
        <argLine>-Xmx1g</argLine>
        ....

But it doesn't work. Haven any of you seen this issue before?

[angelozerr]

@bmix I'm working on this issue with PR #515 It should be available for 0.8.0