How to describe math formula by using xsd? - xsd

i"m trying to validate if an xml element is a multiply of 5 by using xsd. does any 1 have an idea how to do it ?
Thanks,
Itay

I'm pretty sure you can't use general formula for validation. But in your specific case you can use a pattern match to match multiples of 5
<xs:element name="myelement">
<xs:simpleType>
<xs:restriction base="xs:string">
<xs:pattern value="[0-9]*[05]{1}"></xs:pattern>
</xs:restriction>
</xs:simpleType>
</xs:element>

Related

xs:attribute type attribute vs xs:simpleType xs:restriction base attribute

I'm looking at an auto-generated XSD and I noticed that there are quite a few types that are repeated & so am looking to minimize repetition. When I write my own XSDs I normally do it the way its done for the Option1 attribute in the code below, however this XSD does it the way that the Option2 attribute is done.
<xs:element name="baseElement">
<xs:complexType>
<xs:attribute name="Option1" type="NonEmptyString" />
<xs:attribute name="Option2">
<xs:simpleType>
<xs:restriction base="NonEmptyString" />
</xs:simpleType>
</xs:attribute>
</xs:complexType>
</xs:element>
<xs:simpleType name="NonEmptyString">
<xs:restriction base="xs:string">
<xs:minLength value="1"/>
</xs:restriction>
</xs:simpleType>
So I was wondering, is there a difference between these two methods & if not which is better practice? I would be more inclined to use Option1 as it makes the overall file shorter easier to manage

XSD restriction with mathematical constants

My question is quite straight-forward. With XSD, is it possible to restrict a value with mathematical constants like PI. For example, when you want a radian value between 0 and PI.
If not, is there an elegant and simple way to do it ?
Thank you for your help.
You can define a simpleType with the range you want:
<xs:simpleType name="radianType">
<xs:restriction base="xs:double">
<xs:minInclusive value="0"/>
<xs:maxInclusive value="3.14159265358979323846"/>
</xs:restriction>
</xs:simpleType>
And reuse it in elements and attributes:
<xs:element name="horizon" type="radianType"/>

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.

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.

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