XSLT Filter result using XSLT array

Question

I am a beginner in XSLT.

Below is source XML which i receive. Request tag constains the FlightId which is being used to filter the Result tag.

Source XML:

<Response>
    <Request>
        <RequestedFlights>
            <FlightId>2121</FlightId>
            <FlightId>2584</FlightId>
        </RequestedFlights>
    </Request>
    <Result>
        <Flights>
            <Flight>
                <Segments>
                    <Segment>
                        <Id>1</Id>
                        <FlightNumber>2121</FlightNumber>
                    </Segment>
                    <Segment>
                        <Id>2</Id>
                        <FlightNumber>1121</FlightNumber>
                    </Segment>
                </Segments>
            </Flight>
            <Flight>
                <Segments>
                    <Segment>
                        <Id>3</Id>
                        <FlightNumber>2121</FlightNumber>
                    </Segment>
                    <Segment>
                        <Id>4</Id>
                        <FlightNumber>2584</FlightNumber>
                    </Segment>
                </Segments>
            </Flight>
            <Flight>
                <Segments>
                    <Segment>
                        <Id>5</Id>
                        <FlightNumber>2121</FlightNumber>
                    </Segment>
                    <Segment>
                        <Id>6</Id>
                        <FlightNumber>2584</FlightNumber>
                    </Segment>
                    <Segment>
                        <Id>7</Id>
                        <FlightNumber>2023</FlightNumber>
                    </Segment>
                </Segments>
            </Flight>
        </Flights>
    </Result>
</Response>

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" />
    <xsl:variable name="ReqFlights" select="//Request/RequestedFlights/FlightId" />
    <xsl:variable name="FilterFlights" select="//Result/Flights/Flight[Segments/Segment/FlightNumber=$ReqFlights]"/>

    <xsl:template match="Response">
        <FilterResult>
            <ResultCount>
                <xsl:value-of select="count($FilterFlights)"/>
            </ResultCount>
            <xsl:copy>
                <xsl:copy-of select="$FilterFlights"/>
            </xsl:copy>
        </FilterResult>
    </xsl:template>
</xsl:stylesheet>

I received below output using above XSLT.

Output:

<FilterResult>
    <ResultCount>3</ResultCount>
    <Response>
        <Flight>
            <Segments>
                <Segment>
                    <Id>1</Id>
                    <FlightNumber>2121</FlightNumber>
                </Segment>
                <Segment>
                    <Id>2</Id>
                    <FlightNumber>1121</FlightNumber>
                </Segment>
            </Segments>
        </Flight>
            <Flight>
            <Segments>
                <Segment>
                    <Id>3</Id>
                    <FlightNumber>2121</FlightNumber>
                </Segment>
                <Segment>
                    <Id>4</Id>
                    <FlightNumber>2584</FlightNumber>
                </Segment>
            </Segments>
        </Flight>
            <Flight>
            <Segments>
                <Segment>
                    <Id>5</Id>
                    <FlightNumber>2121</FlightNumber>
                </Segment>
                <Segment>
                    <Id>6</Id>
                    <FlightNumber>2584</FlightNumber>
                </Segment>
                <Segment>
                    <Id>7</Id>
                    <FlightNumber>2023</FlightNumber>
                </Segment>
            </Segments>
        </Flight>
    </Response>
</FilterResult>

I would like to receive below output.

Expected Output:

<FilterResult>
    <ResultCount>1</ResultCount>
    <Response>
        <Flight>
            <Segments>
                <Segment>
                    <Id>3</Id>
                    <FlightNumber>2121</FlightNumber>
                </Segment>
                <Segment>
                    <Id>4</Id>
                    <FlightNumber>2584</FlightNumber>
                </Segment>
            </Segments>
        </Flight>
    </Response>
</FilterResult>

Please help me. How should i use the array to filter the response and get expected output. Thanks.

@SeanB.Durkin ResultCount 1 because the "FilterFlights" variable should have only one Flight node. — Ankur Raiyani
– Ankur Raiyani, Commented Nov 21, 2012 at 11:50
So what is the rule here? Does a Flight have to contain all the FlightId's in order for it to be output? — Sean B. Durkin
– Sean B. Durkin, Commented Nov 21, 2012 at 11:50
What is the minimum and maximum number of FlightId s? Is it unbounded? — Sean B. Durkin
– Sean B. Durkin, Commented Nov 21, 2012 at 11:52

Dimitre Novatchev · Accepted Answer · 2012-11-21 12:57:51Z

Use:

/*/Result/*/Flight
            [count(*/*)=count(/*/Request/*/FlightId)
           and
             not(*/*/FlightNumber[not(. = /*/Request/*/FlightId)])
            ]

Here is the complete transformation:

<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
 <xsl:output omit-xml-declaration="yes" indent="yes"/>
 <xsl:strip-space elements="*"/>

 <xsl:template match="/">
     <xsl:variable name="vHits" select=
     "/*/Result/*/Flight
                  [count(*/*)=count(/*/Request/*/FlightId)
                 and
                   not(*/*/FlightNumber[not(. = /*/Request/*/FlightId)])
                   ]"/>
    <FilterResult>
    <ResultCount><xsl:value-of select="count($vHits)"/></ResultCount>
    <Response>
     <xsl:copy-of select="$vHits"/>
    </Response>
  </FilterResult>
 </xsl:template>
</xsl:stylesheet>

When this transformation is applied on the provided XML document:

<Response>
    <Request>
        <RequestedFlights>
            <FlightId>2121</FlightId>
            <FlightId>2584</FlightId>
        </RequestedFlights>
    </Request>
    <Result>
        <Flights>
            <Flight>
                <Segments>
                    <Segment>
                        <Id>1</Id>
                        <FlightNumber>2121</FlightNumber>
                    </Segment>
                    <Segment>
                        <Id>2</Id>
                        <FlightNumber>1121</FlightNumber>
                    </Segment>
                </Segments>
            </Flight>
            <Flight>
                <Segments>
                    <Segment>
                        <Id>3</Id>
                        <FlightNumber>2121</FlightNumber>
                    </Segment>
                    <Segment>
                        <Id>4</Id>
                        <FlightNumber>2584</FlightNumber>
                    </Segment>
                </Segments>
            </Flight>
            <Flight>
                <Segments>
                    <Segment>
                        <Id>5</Id>
                        <FlightNumber>2121</FlightNumber>
                    </Segment>
                    <Segment>
                        <Id>6</Id>
                        <FlightNumber>2584</FlightNumber>
                    </Segment>
                    <Segment>
                        <Id>7</Id>
                        <FlightNumber>2023</FlightNumber>
                    </Segment>
                </Segments>
            </Flight>
        </Flights>
    </Result>
</Response>

the wanted, correct result is produced:

<FilterResult>
   <ResultCount>1</ResultCount>
   <Response>
      <Flight>
         <Segments>
            <Segment>
               <Id>3</Id>
               <FlightNumber>2121</FlightNumber>
            </Segment>
            <Segment>
               <Id>4</Id>
               <FlightNumber>2584</FlightNumber>
            </Segment>
         </Segments>
      </Flight>
   </Response>
</FilterResult>

Explanation:

Proper use of the double negation law.

Thanks. For the given source XML your solution works. But when i need to apply same law for different structured XML. Should i create new Question or edit this?
@AnkurRaiyani, It is better for everybody if you create a new question -- otherwise you'll destroy the first question, or make it less readable.

Sean B. Durkin · Accepted Answer · 2012-11-21 13:16:45Z

<xsl:stylesheet version="1.0"
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
  xmlns:exsl="http://exslt.org/common"
  extension-element-prefixes="exsl">
<xsl:output omit-xml-declaration="yes" indent="yes"/>
<xsl:strip-space elements="*" />  

<xsl:variable name="requested"
  select="/Response/Request/RequestedFlights/FlightId/text()" />

<xsl:template name="flights-as-string">
  <xsl:param name="Id" />
  <xsl:for-each select="$Id">
    <xsl:sort select="." />
    <xsl:value-of select="concat('[',.,']')" />
  </xsl:for-each>  
</xsl:template>

<xsl:variable name="requested-str-nodeset">
  <xsl:call-template name="flights-as-string">
    <xsl:with-param name="Id" select="$requested" />
  </xsl:call-template>
</xsl:variable>  
<xsl:variable name="requested-str" select="exsl:node-set($requested-str-nodeset)/text()" />

<xsl:template match="/*">
  <xsl:variable name="flight-output">
    <xsl:apply-templates select="Result/Flights/Flight" />
  </xsl:variable>
  <FilterResult>
    <ResultCount><xsl:value-of select="
      count( exsl:node-set($flight-output)/Flight)" /></ResultCount>
    <Response>
      <xsl:copy-of select="$flight-output" />
    </Response>
  </FilterResult>
</xsl:template>

<xsl:template match="Flight">
  <xsl:variable name="actual-str">
    <xsl:call-template name="flights-as-string">
      <xsl:with-param name="Id" select="Segments/Segment/FlightNumber/text()" />
    </xsl:call-template>
  </xsl:variable>  
  <xsl:if test="$requested-str = exsl:node-set($actual-str)/text()">
      <xsl:copy-of select="." />
  </xsl:if>
</xsl:template>

</xsl:stylesheet>

Collectives™ on Stack Overflow

XSLT Filter result using XSLT array

2 Answers 2

2 Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

2 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related