Hash Functions

Overview

This article will outline how to implement the hash functions that we have made available in Zynk.

• Namespace urn:HashFunctions
• Available since Zynk Workflow 2.11.0

XSLT

Declarations

To use hash functions, you need to add the namespace declaration to your XSLT file:

<xsl:stylesheet 
    version="1.0"
    xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
    xmlns:HashFunctions="urn:HashFunctions"
    exclude-result-prefixes="HashFunctions">

    <!-- transformation -->

</xsl:stylesheet>

Functions

• PopulateHashes Seeds a hash table based on the parameters provided.
  • string hashTable, XPathNodeIterator xpath, string keyXPath
• EmptyHashes Clears the given hash table.
  • string hashTable
• IsNew Checks if a record is new to the hash table based on the parameters provided.
  • string hashTable, XPathNodeIterator xpath, string keyXPath
• HasChanged Checks if a record has changed based on the parameters provided.
  • string hashTable, XPathNodeIterator xpath, string keyXPath

Example

Input

<?xml version="1.0" encoding="utf-8"?>
<Company>
    <Products>
        <Product>
            <Sku>ABC</Sku>
            <Supplier>Bob</Supplier>
            <Priority>2</Priority>
        </Product>
        <Product>
            <Sku>ZXY</Sku>
            <Supplier>Sam</Supplier>
            <Priority>1</Priority>
        </Product>
        <Product>
            <Sku>123</Sku>
            <Supplier>Jon</Supplier>
            <Priority>3</Priority>
        </Product>
    </Products>
</Company>

XSLT

<xsl:stylesheet 
    version="1.0"
    xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
    xmlns:HashFunctions="urn:HashFunctions"
    xmlns:msxsl="urn:schemas-microsoft-com:xslt"
    exclude-result-prefixes="HashFunctions msxsl">
    
    <xsl:output indent="yes"/>
    
    <xsl:template match="/">
        <xsl:variable name="Source">
            <Stocks>
                <Stock>
                    <Code>ABC</Code>
                </Stock>
                <Stock>
                    <Code>ZXY</Code>
                </Stock>
            </Stocks>
        </xsl:variable>
        
        <xsl:variable name="Populate" select="HashFunctions:PopulateHashes('Products', msxsl:node-set($Source)/Stocks/Stock, 'Code')"/>
        
        <Data>
            <xsl:for-each select="Company/Products/Product">
                <Datum>
                    <IsNew><xsl:value-of select="HashFunctions:IsNew('Products', ., 'Sku')"/></IsNew>
                </Datum>
            </xsl:for-each>
        </Data>
    </xsl:template>
    
</xsl:stylesheet>

Output

<?xml version="1.0" encoding="utf-8"?>
<Data>
    <Datum>
        <IsNew>false</IsNew>
    </Datum>
    <Datum>
        <IsNew>false</IsNew>
    </Datum>
    <Datum>
        <IsNew>true</IsNew>
    </Datum>
</Data>