semi colon delimited xs:attribute xsd - attributes

I'm currently building an XSD to validate some XML I'm working on, I'm guessing this probably isn't possible but I'm wondering if there is some way to enforce an attribute that is a ";" delimited list for example
<nbsp style="cell-width:1.29;background-color:#99CC00;"/>
similar to the way the style attribute works in html.
Thanks in advance

You can specify a type which must match a specific pattern.
Example:
<simpleType name='better-us-zipcode'>
<restriction base='string'>
<pattern value='[0-9]{5}(-[0-9]{4})?'/>
</restriction>
</simpleType>

Use a regular expression to validate the content.
<xs:attribute name="code">
<xs:simpleType>
<xs:restriction base="xs:string">
<xs:pattern value="[A-Z][A-Z]"/>
</xs:restriction>
</xs:simpleType>
</xs:attribute>
see also
http://www.w3schools.com/Schema/el_attribute.asp
and
http://www.w3schools.com/schema/schema_simple_attributes.asp
and
http://www.w3schools.com/schema/schema_facets.asp
test your regexp here: http://regexlib.com/RETester.aspx

Related

XSD: restrict attribute to xs:float or ""

I'm trying to define an element type in XSD, for which i want an optional attribute, which if present can either contain a float, or be empty (but still present).
i.e:
<xs:element name="MyElement">
<xs:complexType>
<xs:attribute name="optionalFloatAttribute" type="xs:float" use="optional"/>
</xs:complexType>
</xs:element>
Needs "fixing" to allow all of the following xml:-
<MyElement/>
or
<MyElement optionalFloatAttribute=""/>
or
<MyElement optionalFloatAttribute="3.14159"/>
The only way I can see of doing this is to change type to xs:string, and use xs:restriction with a regular expression. But this doesn't seem very ideal to me. Is there a better way?
And I have to be able to support these variations of the xml - the program and existing xml is legacy, and I am trying to back-create a schema to match the myriad variations I see in what we have to regard as valid xml.
You can define custom type for that by combining float and empty string:
<xs:element name="MyElement">
<xs:complexType>
<xs:attribute name="optionalFloatAttribute" type="emptyFloat" use="optional"/>
</xs:complexType>
</xs:element>
<xs:simpleType name="emptyFloat">
<xs:union>
<xs:simpleType>
<xs:restriction base='xs:string'>
<xs:length value="0"/>
</xs:restriction>
</xs:simpleType>
<xs:simpleType>
<xs:restriction base='xs:float'>
</xs:restriction>
</xs:simpleType>
</xs:union>
</xs:simpleType>
Or using regExp:
<xs:simpleType name="emptyFloat">
<xs:restriction base="xs:string">
<xs:pattern value="-?\d*\.?\d*"/>
</xs:restriction>
</xs:simpleType>
If you could stand using an element rather than an attribute you could make the xs:float nillable. This way you can use the xsi:nil="true" in your instance document to indicate that the element has no value:
<!-- definition -->
<xs:element name="quantity" type="xs:float" nillable="true" />
<!-- instance -->
<quantity xsi:nil="true" />
No equivalent for attributes though.
I don't think there's a way to handle this and use xs:float. Fundamentally it comes down to the fact that empty string isn't a valid number. You'd either normally expect a value of 0, or for the element to be missing altogether. There's a good explanation as the answer to the following question:
Empty elements for primitve datatypes forbidden in XSD
It seems that the option of using xs:string and a regexp might be your best plan.

XML schema restriction that allows empty elements or specific pattern

I want to define an element in XML schema that will allow for an empty string or some specific pattern, e.g.,:
<Code/>
<Code></Code>
<Code> </Code>
<Code>11111</Code>
<Code>111111</Code> - INVALID
<Code>AAAAA</Code> - INVALID
How can I modify my existing restriction?
<xs:element name="Code">
<xs:simpleType>
<xs:restriction base="xs:string">
<xs:pattern value="[0-9]{5}" />
</xs:restriction>
</xs:simpleType>
</xs:element>
Add \s as another choice to your regex to allow whitespace characters [#x20\t\n\r] (That is: "regular" space, tab, line feed, carriage return. Non-breaking space is not included.)
<xs:simpleType>
<xs:restriction base="xs:string">
<xs:pattern value="\s*|[0-9]{5}" />
</xs:restriction>
</xs:simpleType>
Use "^$|pattern" it should work as ^$ matches just null values.

How to allow typed values to be empty with an XML schema?

I have some XML documents over which I have no control whatsoever. Their structure is well-defined, but it is described in a bunch of PDFs, which, despite being very exact, don't make automated validation very tractable. I'm trying to write a XML schema to make (most of) the rules in those PDFs executable.
All the elements are mandatory. But about half of them can be either empty or have simple typed content.
When defining datatypes for these elements, I defined two versions of each: a "normal" one, and another that can be empty. I did this by defining unions with an empty datatype:
<xs:simpleType name="empty">
<xs:restriction base="xs:string">
<xs:length value="0"/>
</xs:restriction>
</xs:simpleType>
<xs:simpleType name="codPostal">
<xs:restriction base="xs:string">
<xs:pattern value="^[0-9]{4}-[0-9]{3}$"/>
</xs:restriction>
</xs:simpleType>
<xs:simpleType name="opt_codPostal">
<xs:union memberTypes="empty codPostal"/>
</xs:simpleType>
Is there a less repetitive way of doing this?
You can use xs:nillable.
In XSD
<xs:simpleType name="codPostal">
<xs:restriction base="xs:string">
<xs:pattern value="^[0-9]{4}-[0-9]{3}$"/>
</xs:restriction>
</xs:simpleType>
<xs:element name="OptionalString" type="codPostal" nillable="true" />
In Document
<OptionalString xsi:nil="true"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" />
This is most useful for non-string types (e.g. datetime etc) as for strings you could just use zero length.
<OptionalString />
Unfortunately you need to specify the "nil" attribute on the document. As far as I know, the only non-intrusive way to do what you want is the union type approach that you've already chosen.

Xsd, Validate empty or minimum length string

Currently I have an Xsd validating with this rule
<xs:simpleType name='shipTo'>
<xs:restriction base='xs:string'>
<xs:minLength value='6'/>
</xs:restriction>
</xs:simpleType>
I need to allow blanks as well, but if a value is entered, it's minimum length should still be 6.
Can I do this without resorting to this xs:pattern and regex?
<xs:simpleType name='shipTo'>
<xs:restriction base='xs:string'>
<xs:pattern value='^(?:|[\w]{6,})$'/>
</xs:restriction>
</xs:simpleType>
The regex will work, but you should really make the element that you will be assigning shipTo to optional, and not include it in the XML file if it has no value.

How to declare a non-string element as having optional content in XML Schema

I have seen XML Schema element with attributes containing only text but I have an element that's an xs:dateTime instead.
The document I'm trying to write a schema for looks like this:
<web-campaigns>
<web-campaign>
<id>1231</id>
<start-at nil="true"/>
</web-campaign>
<web-campaign>
<id>1232</id>
<start-at>2009-08-08T09:00:00Z</start-at>
</web-campaign>
</web-campaigns>
Sometimes the xs:dateTime element has content, sometimes it doesn't.
What I have so far (which doesn't validate yet) is:
<xs:element name="start-at">
<xs:complexType mixed="true">
<xs:simpleContent>
<xs:extension base="xs:dateTime">
<xs:attribute name="nil" default="false" type="xs:boolean" use="optional" />
</xs:extension>
</xs:simpleContent>
</xs:complexType>
</xs:element>
If I replace xs:dateTime with xs:string, I can validate the document just fine, but I really want an xs:dateTime, to indicate to consumers what's in that element. I tried with/without mixed="true" as well, to no avail.
If it makes a difference, I validate using xmllint (on Mac OS X 10.5) and XML Schema Validator
you can define your own types as union of types.
1/ define the "empty" type as a string that only allows "" ähm nothing :)
<xs:simpleType name="empty">
<xs:restriction base="xs:string">
<xs:enumeration value=""/>
</xs:restriction>
</xs:simpleType>
2/ next define a type that allows date AND empty
<xs:simpleType name="empty-dateTime">
<xs:union memberTypes="xs:dateTime empty"/>
</xs:simpleType>
3/ declare all your nullable datetime elements as type="empty-dateTime"
You need
<xs:element name="start-at" minOccurs="0">
mixed-mode isn't relevant to your situation, you don't need that. By default, minOccurs="1", i.e. the element is mandatory.
With minOccurs="0", you either specify the element with content, or not at all. If you want to be able to permit <start-at/>, then you cannot use xs:dateTime.

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