XML Sorting

bpoole · March 20th, 2016, 01:01 PM

Really new to XSLT but have managed to put together some code that combines multiple xml files into one. I now want to sort the result but am having some difficulty. I have searched several sites but not found what I need, or one I understand. My source xml file looks like below. As you see it is tv programming. I am trying to sort based on the start value putting the in chronological order starting with earliest to latest. Of course each programme element would have to move with it's respective times. I can post my xslt used to create the xml but see no reason since the sort will be made on the final put shown below and save to new file. Thanks in advance.

Code:

<?xml version="1.0" encoding="UTF-8"?>
<tv>
  <start value="201603182100">
    <programme>
      <id>I396.20453.schedulesdirect.org</id>
      <title>Shark Tank</title>
      <description>A product that keeps beer cold longer; a new twist to the vending machine; pet-safe bug repellents; vegetable smoothies; an update on Wombi Rose and LovePop.</description>
    </programme>
    <programme>
      <id>I265.10035.schedulesdirect.org</id>
      <title>60 Days In: Time Out</title>
      <description>A young man from a rough neighborhood witnesses a violent fight between inmates; the inmates become suspicious of Robert; Zac makes a mistake.</description>
    </programme>
 <start value="201603181900">
    <programme>
      <id>I254.59337.schedulesdirect.org</id>
      <title>The Bourne Identity</title>
      <description>A woman (Franka Potente) helps an amnesiac (Matt Damon), who has a dangerous past, to dodge assassins as he tries to learn about himself.</description>
    </programme>
    <programme>
      <id>I12.11775.schedulesdirect.org</id>
      <title>2016 NCAA Basketball Tournament</title>
      <description>Coach Bob Huggins led the No. 3 seed West Virginia Mountaineers to a second-place finish in the difficult Big 12. They take on Stephen F. Austin State in the first round. The Lumberjacks earned an automatic bid by winning the Southland Conference.</description>
    </programme>

bpoole · March 20th, 2016, 02:52 PM

Here is what I came up with:

Code:

<xsl:transform xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">
<xsl:output version="1.0" encoding="UTF-8" indent="yes" />
<xsl:strip-space elements="*"/>

<xsl:key name="startkey" match="programme" use="@start" />

  <xsl:template match="tv">
    <xsl:copy>
      <xsl:for-each select="programme[generate-id()= generate-id(key('startkey',@start)[1])]">
        <xsl:sort select="@start"/>
        <start>
          <xsl:attribute name="value"><xsl:value-of select="substring(@start,1,12)"/></xsl:attribute>   
          <xsl:for-each select="key('startkey',@start)">
            
            <xsl:copy>
            <id><xsl:value-of select="@channel"/></id>
              <title><xsl:value-of select="title"/></title>
              <description><xsl:value-of select="desc"/></description>
             </xsl:copy>
            
          </xsl:for-each>
        </start>
      </xsl:for-each>
    </xsl:copy>
  </xsl:template>    

</xsl:transform>

mhkay · March 20th, 2016, 05:18 PM

I'm a little confused, because you describe the XML that you have shown as the source XML, but your logic appears to be taking programme elements that each have a start attribute, and grouping those that have the same start time to create a start element for that start time - in other words it looks to me as if the XML you have shown is the output rather than the input of your transformation. In which case, congratulations, you have discovered the Muenchian grouping method which is one of the trickiest things to program in XSLT 1.0. It's much easier, however, in XSLT 2.0, which has an xsl:for-each-group instruction. There are still some environments where no XSLT 2.0 processor is available but you should be using XSLT 2.0 if you possibly can.

bpoole · March 21st, 2016, 07:36 AM

Sorry for the confusion, you are correct this is the output . When I originally posted I was thinking of creating the sort as a third transformation, so the xml shown would have been the output for the second but the source for a third. After figuring out the sort I was able to place it in the second transformation which I posted. So, now the code posted sorts the information based on the start value and keeps the programme info grouped.
Thanks for looking.