Why variable goes wrong as "document-node()" in sub xsl:template? - xslt

Looking directly at the example:
<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:xs="http://www.w3.org/2001/XMLSchema"
exclude-result-prefixes="xs"
version="3.0">
<xsl:template match="/">
<xsl:variable name="v1" select="." as="document-node()"/>
<xsl:apply-templates select=".//name"/>
</xsl:template>
<xsl:template match="name">
<xsl:variable name="v2" select="." as="document-node()"/>
<xsl:apply-templates/>
</xsl:template>
</xsl:stylesheet>
source xml:
<?xml version="1.0" encoding="UTF-8"?>
<root>
<item>
<name>John</name>
<age>21</age>
</item>
</root>
The question is that: variable v1 can be declarated well, but v2 has an error "Required item type of value of variable $v2 is document-node(); supplied expression (.) has item type element(Q{}name)".
I looked up the definition of document-node() in w3c xpath document, it says "document-node() matches any document node." 2.5.5.2 Matching an ItemType and an Item. I still can't understand why v2 is wrong with type document-node().
I have make a online test demo

Because it's not a document-node(), it's an element(). Use element() instead. <xsl:template match="/"> matches a document-node(), and <xsl:template match="name"> matches an element() node.

Related

Copy value of node using reference into other node

I'm trying to copy the value of an XML node referenced by an identifier into another node of the graph.
The orignal file looks like this:
<Root>
<Object id="Id1">
<FileName>file.png</FileName>
</Object>
<Description>
<Content>
<Title>Nice Object</Title>
<ObjectReference>Id1</ObjectReference>
</Content>
</Description></Root>
In XSLT, I use a variable to identify the value of the reference node identifier.
<xsl:template match="Content">
<xsl:variable name="IdObject">
<xsl:value-of select="ObjectReference"/>
</xsl:variable>
<Out>
<Title>
<xsl:value-of select="Title"/>
</Title>
<FileName>
<xsl:value-of select="//Object[#id='$IdObject']/Filename"/>
</FileName>
</Out></xsl:template>
The value of 'FileName' is not copied. I select the wrong reference node, I think. I tried with 'Ancestor::' and 'Parent::'. That doesn't work either.
Do you have an idea?
Thanks
I would like to obtain the following result :
<Out>
<Name>Nice Object</Name>
<FileName>file.png</FileName>
</Out>
XSLT has a built-in key mechanism for resolving cross-references. The following stylesheet:
XSLT 1.0
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output method="xml" version="1.0" encoding="UTF-8" indent="yes"/>
<xsl:key name="obj" match="Object" use="#id" />
<xsl:template match="Content">
<Out>
<xsl:copy-of select="Title"/>
<xsl:copy-of select="key('obj', ObjectReference)/FileName"/>
</Out>
</xsl:template>
<xsl:template match="text()"/>
</xsl:stylesheet>
applied to your input example, will return:
Result
<?xml version="1.0" encoding="UTF-8"?>
<Out>
<Title>Nice Object</Title>
<FileName>file.png</FileName>
</Out>
P.S. Your attempt did not work because:
You quoted the reference to the variable;
You used Filename instead of FileName.

Replace values using Key defined with inline variable

I'm trying to understand the usage of keys and can't get my example to work.
Starting with this XML:
<items>
<item>Blue</item>
<item>Green</item>
<item>Orange</item>
</items>
I want to get this output XML:
<items>
<item>PURPLE</item>
<item>BLACK</item>
<item>PINK</item>
</items>
I defined the mapping directly in a variable in the XSLT transformation:
<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:xs="http://www.w3.org/2001/XMLSchema"
version="2.0">
<xsl:output method="xml" indent="yes"/>
<xsl:variable name="mappings">
<mapping orig="Blue" repla="PURPLE"/>
<mapping orig="Green" repla="BLACK"/>
<mapping orig="Orange" repla="PINK"/>
</xsl:variable>
<xsl:key name="mappingsKey" match="$mappings/mapping" use="#orig"/>
<xsl:template match="items">
<xsl:copy>
<xsl:apply-templates/>
</xsl:copy>
</xsl:template>
<xsl:template match="item">
<xsl:copy>
<xsl:value-of select="key('mappingsKey',.)"/>
</xsl:copy>
</xsl:template>
</xsl:stylesheet>
I know I'm missing the instruction to tell which is the replacement value, but don't know how to define it.
Example available here: https://xsltfiddle.liberty-development.net/ejivdHp/1
Thanks.
The $mappings variable is in a different document than the processed XML. You need to point the key() function to there. And you also need to select the repla attribute:
<xsl:value-of select="key('mappingsKey', ., $mappings)/#repla"/>
Referencing the variable in the match pattern of the xsl:key element is meaningless.
https://xsltfiddle.liberty-development.net/ejivdHp/2

Find node containing the most recent date when date needs converted to valid date format

I need an xPath to be used in a global variable which will select the 'Policy' node with the most recent dateTime (2014-12-02-04:00). Unfortanately the Time delimeter is a dash instead of 'T' so I can't use max() straight away. If I try to use substring or translate to remove the dashes and colon to simply compare numbers I get the error which states that there cannot be more that one sequence in those functions.
Is there a way to evaluate PolicyEffectiveDate from the root node when it is in 2014-12-02-04:00 format?
/Policies/PolicySummary/Policy[2]/PolicyEffectiveDate
XSLT 2.0 is OK. Also, note that I don't have control over the XML format. Thanks.
Given sample XML of:
<?xml version="1.0" encoding="UTF-8"?>
<Policies>
<PolicySummary>
<Policy>
<PolicyNumber>123</PolicyNumber>
<PolicyEffectiveDate>2014-06-01-04:00</PolicyEffectiveDate>
</Policy>
<Policy>
<PolicyNumber>1234</PolicyNumber>
<PolicyEffectiveDate>2014-12-02-04:00</PolicyEffectiveDate>
</Policy>
<Policy>
<PolicyNumber>12345</PolicyNumber>
<PolicyEffectiveDate>2014-08-02-04:00</PolicyEffectiveDate>
</Policy>
</PolicySummary>
</Policies>
You can simply sort the policies by their "dates" as text. For example:
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output method="xml" version="1.0" encoding="utf-8" indent="yes"/>
<xsl:strip-space elements="*"/>
<xsl:template match="/">
<xsl:for-each select="Policies/PolicySummary/Policy">
<xsl:sort select="PolicyEffectiveDate" data-type="text" order="descending"/>
<xsl:if test="position()=1">
<xsl:copy-of select="."/>
</xsl:if>
</xsl:for-each>
</xsl:template>
</xsl:stylesheet>
will return:
<?xml version="1.0" encoding="utf-8"?>
<Policy>
<PolicyNumber>1234</PolicyNumber>
<PolicyEffectiveDate>2014-12-02-04:00</PolicyEffectiveDate>
</Policy>
in your example.

XPath relative path in expression

I am in 'group' node. From it, I want to find such 'item' node, that has 'id' attribute equals to current's 'group' node 'ref_item_id' attribute value. So in my case, by being in 'group' node B, I want 'item' node A as output. This works:
<xsl:value-of select="preceding-sibling::item[#id='1']/#description"/>
But this doesn't (gives nothing):
<xsl:value-of select="preceding-sibling::item[#id=#ref_item_id]/#description"/>
When I type:
<xsl:value-of select="#ref_item_id"/>
I have '1' as result. So this attribute is for sure accessible, but I can't find path to it from XPath expression above. I tried many '../' combinations, but couldn't get it work.
Code to test: http://www.xmlplayground.com/7l42fo
Full XML:
<?xml version="1.0" encoding="UTF-8"?>
<root>
<item description="A" id="1"/>
<item description="C" id="2"/>
<group description="B" ref_item_id="1"/>
</root>
Full XSLT:
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output method="text" indent="no"/>
<xsl:template match="root">
<xsl:for-each select="group">
<xsl:value-of select="preceding-sibling::item[#id=#ref_item_id]/#description"/>
</xsl:for-each>
</xsl:template>
</xsl:stylesheet>
This has to do with context. As soon as you enter a predicate, the context becomes the node currently being filtered by the predicate, and no longer the node matched by the template.
You have two options - use a variable to cache the outer scope data and reference that variable in your predicate
<xsl:variable name='ref_item_id' select='#ref_item_id' />
<xsl:value-of select="preceding-sibling::item[#id=$ref_item_id]/#description"/>
or make use of the current() function
<xsl:value-of select="preceding-sibling::item[#id=current()/#ref_item_id]/#description"/>
Your expression searches for an item whose id attribute matches its own ref_item_id. You need to capture the current ref_item_id in an xsl:variable and refer to that xsl:variable in the expression.
One more possible solution using xsl:key
<xsl:key name="kItemId" match="item" use="#id" />
<xsl:template match="root">
<xsl:for-each select="group">
<xsl:value-of select="key('kItemId', #ref_item_id)[1]/#description"/>
</xsl:for-each>
</xsl:template>
Looking at the XML, if I assume that you have <item> and <group> as siblings and in any order.
Then a sample input XML would look like the following.
<?xml version="1.0" encoding="UTF-8"?>
<root>
<item description="A" id="1"/>
<item description="C" id="2"/>
<group description="B" ref_item_id="1"/>
<item description="D" id="1"/>
<group description="E" ref_item_id="2"/>
</root>
Now, if the goal is to extract the description of all the <item> nodes whose id is matching with corresponding <group> *nodes ref_item_id*. Then we can simply loop over only such <item> nodes and get their description.
<xsl:output method="text" indent="no"/>
<xsl:template match="root">
<xsl:for-each select="//item[(./#id=following-sibling::group/#ref_item_id) or (./#id=preceding-sibling::group/#ref_item_id)]">
<xsl:value-of select="./#description"/>
</xsl:for-each>
</xsl:template>
</xsl:stylesheet>
Since you say that nodes are having unique id and all nodes are placed before nodes.
I would recommend you to use the following XSL and loop over specific nodes instead of nodes.
<xsl:output method="text" indent="no"/>
<xsl:template match="root">
<xsl:for-each select="//item[./#id=following-sibling::group/#ref_item_id]">
<xsl:value-of select="./#description"/>
</xsl:for-each>
</xsl:template>
</xsl:stylesheet>

XSLT 1.0 text nodes printing by default

I have looked at XSL xsl:template match="/" but the match pattern that triggered my question is not mentioned there.
I have a rather complex XML structure:
<?xml version="1.0" encoding="UTF-8"?>
<MATERIAL_DATA>
<LOG>
<USER>Peter</USER>
<DATE>2011-02-18</DATE>
<MATERIALS>
<item>
<MATNR>636207</MATNR>
<TEXTS>
<item>
<TEXT>granola bar 40gx24</TEXT>
</item>
</TEXTS>
<PRICES>
<item>
<MATNR>636207</MATNR>
<COST>125.78</COST>
</item>
</PRICES>
<SALESPRICES>
<item>
<B01>
<MATNR>636207</MATNR>
<CURR>CZK</CURR>
<DATBI>9999-12-31</DATBI>
<DATAB>2010-10-05</DATAB>
</B01>
<B02>
<item>
<PRICE>477.60</PRICE>
<KUNNR>234567</KUNNR>
</item>
</B02>
</item>
</SALESPRICES>
</item>
</MATERIALS>
</LOG>
</MATERIAL_DATA>
Now if I apply the following XSLT, my output looks correct:
<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">
<xsl:output method="xml" indent="yes" encoding="UTF-8"/>
<xsl:template match="node() | #*">
<xsl:apply-templates select="* | #*" />
</xsl:template>
<xsl:template match="B02">
<xsl:element name="Mi">
<xsl:value-of select="item/KUNNR"/>
</xsl:element>
</xsl:template>
</xsl:stylesheet>
I get the output:
<?xml version="1.0" encoding="UTF-8"?>
<Mi>234567</Mi>
But if I apply the XSLT:
<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">
<xsl:output method="xml" indent="yes" encoding="UTF-8"/>
<xsl:template match="/*">
<xsl:element name="MenuItems">
<xsl:apply-templates select="LOG/MATERIALS/item/SALESPRICES/item"/>
</xsl:element>
</xsl:template>
<xsl:template match="B02">
<xsl:element name="Mi">
<xsl:value-of select="item/KUNNR"/>
</xsl:element>
</xsl:template>
</xsl:stylesheet>
the output looks like this:
<?xml version="1.0" encoding="UTF-8"?>
<MenuItems>
636207
CZK
9999-12-31
2010-10-05
<Mi>234567</Mi>
</MenuItems>
All values from the element <B01> are in the output! But why - I am not matching <B01>!?
How does
<xsl:template match="node() | #*">
<xsl:apply-templates select="* | #*" />
</xsl:template>
make the output come out correctly? All I am doing with this is match all nodes or attributes and apply-templates to everything or all attributes.
But in my opinion it should not make a difference to when I exactly match <B01>!
Why is this happening?
XSLT includes the following default templates (among others):
<!-- applies to both element nodes and the root node -->
<xsl:template match="*|/">
<xsl:apply-templates/>
</xsl:template>
<!-- copies values of text and attribute nodes through -->
<xsl:template match="text()|#*">
<xsl:value-of select="."/>
</xsl:template>
In your first stylesheet you're implicitly matching all text nodes with node(), thus overriding the default action. Then, in the B2 template, you output your target value and apply no further templates, which stops processing.
In the second stylesheet, you explicitly apply templates to all children of LOG/MATERIALS/item/SALESPRICES/item, causing the default templates to process the nodes you don't explicitly handle. Because you explicitly handle B2 without applying templates to its children, the default templates are never invoked for those nodes. But the default templates are applied to the children of B1.
Adding the following template to your second stylesheet would override the default action for text nodes:
<xsl:template match="text()|#*"></xsl:template>
With the following result:
<?xml version="1.0" encoding="UTF-8"?>
<MenuItems><Mi>234567</Mi></MenuItems>
More:
http://www.w3.org/TR/xslt#built-in-rule
Looks like you are running into the built in template rules.
Specifically the text rule - this will copy text nodes if not overridden.