使用xslt将xml结构转换为另一个xml结构

I have a question. I have the following source xml file:

我有个问题。我有以下源xml文件:

Source xml:

<Container>
  <DataHeader>
    <c id="b" value="TAG" />
    <c id="g" value="Info" /> 
  </DataHeader>
  <Data>
    <Rows>
      <r no="1">
        <c id="b" value="uid1" uid="T.A.uid1" />
        <c id="g" value="uid1|tag1|attr1|somevalue1" />
      </r>
   <r no="1">
        <c id="b" value="uid1" uid="T.A.uid1" />
        <c id="g" value="uid1|tag1|attr2|somevalue2" />
      </r>
      <r no="2">
        <c id="b" value="uid1" uid="T.A.uid1" />
        <c id="g" value="uid1|tag2|attr3|somevalue3" />
      </r>
    <r no="10">
        <c id="b" value="uid2" uid="T.A.uid2" />
        <c id="g" value="uid2|tag1|attr1|somevalue4" />
      </r>
      <r no="11">
        <c id="b" value="uid2" uid="T.A.uid2" />
        <c id="g" value="uid2|tag2|attr3|somevalue5" />
      </r>
   </Rows>
  </Data>
</Container>

The element 'c' with id 'g' is important in the source xml. This is a concatened string which values are seperated by a '|'. We need this values to make the target xml. The element 'c' with id 'b' you can use to separate the 'uid'.

id为'g'的元素'c'在source xml中很重要。这是一个串联的字符串,其值由“|”分隔。我们需要这个值来制作目标xml。 id为'b'的元素'c'可用于分隔'uid'。

example and explantion of values:

示例和值的解释:

 <c id="g" value="uid1|tag1|attr1|somevalue1" />
 **uid value** | element node | **attribute** | attribute value
 **uid1** | tag1 | **attr1** |somevalue1

Al elements with the same 'uid' have to be aggregated into 1 single "TestTag" element (see target xml). Al attributes (attr1, attr2) with same parent element (for example 'tag1') needs to be added to 1 element. I only can make use of xslt(xpath) 1.0.

具有相同'uid'的Al元素必须聚合成1个单独的“TestTag”元素(参见目标xml)。需要将具有相同父元素(例如'tag1')的Al属性(attr1,attr2)添加到1个元素。我只能使用xslt(xpath)1.0。

The target xml file should look like this after transforming.

转换后,目标xml文件应如下所示。

Target xml after transformed by xsl:

在xsl转换后定位xml:

<Container>
 <TestTag>
    <object UID="T.A.uid1" Name="uid1"/>
    <tag1 attr1="somevalue1" attr2="somevalue2"/>
    <tag2 attr3="*somevalue3"/>
 </TestTag>
 <TestTag>
    <Iobject UID="T.A.uid2" Name="uid2"/>
    <tag1 attr1="somevalue4" />
    <tag2 attr3="somevalue5"/>
 </TestTag>
</Container>

What are possible solutions for transforming source xml to target xml? I tried several things but I'm stuck right now.

将源xml转换为目标xml有哪些可能的解决方案?我尝试了几件事,但我现在卡住了。

1 个解决方案

#1

This is not exactly difficult, but is mind-boggling due to extensive (yet necessary) nested use of substring-before() and substring-after().

这并不是很困难,但由于对substring-before()和substring-after()的广泛(但必要)嵌套使用,这是令人难以置信的。

<xsl:stylesheet 
  version="1.0"
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
>
  <!-- index <c> nodes by their @id + "uid value" -->
  <xsl:key name="kObject"    match="r/c" use="
    concat(@id, '|', @value)
  " />
  <!-- index <c> nodes by their @id + "uid value" -->
  <xsl:key name="kTagByUid"  match="r/c" use="
    concat(@id, '|', substring-before(@value, '|'))
  " />
  <!-- index <c> nodes by their @id + "uid value" + "tag name" -->
  <xsl:key name="kTagByName" match="r/c" use="
    concat(@id, '|',
      substring-before(
        @value, 
        substring-after(substring-after(@value, '|'), '|')
      )
    )
  " />

  <xsl:variable name="vTagId"  select="/Container/DataHeader/c[@value='TAG'][1]/@id" />
  <xsl:variable name="vInfoId" select="/Container/DataHeader/c[@value='Info'][1]/@id" />

  <!-- processing starts here -->
  <xsl:template match="Container">
    <xsl:copy>
      <!-- apply templates to unique <c @id=$vTagId> tags -->
      <xsl:apply-templates mode="tag" select="
        Data/Rows/r/c[@id=$vTagId][
          generate-id()
          =
          generate-id(key('kObject', concat(@id, '|', @value))[1])
        ]
      " />
    </xsl:copy>
  </xsl:template>

  <xsl:template match="c" mode="tag">
    <TestTag>
      <object UID="{@uid}" name="{@value}" />
      <!-- apply templates to unique <c @id="g"> tags -->
      <xsl:apply-templates mode="info" select="
        key('kTagByUid', concat($vInfoId, '|', @value))[
          generate-id()
          =
          generate-id(
            key(
              'kTagByName', 
              concat(@id, '|', 
                substring-before(
                  @value, 
                  substring-after(substring-after(@value, '|'), '|')
                )
              )
            )[1]
          )
        ]
      " />
    </TestTag>
  </xsl:template>

  <xsl:template match="c" mode="info">
    <!-- select 'uid1|tag1|' - it's the key to kTagByName -->
    <xsl:variable name="key"  select="substring-before(@value, substring-after(substring-after(@value, '|'), '|'))" />
    <!-- select 'tag1' - it's the element name -->
    <xsl:variable name="name" select="substring-before(substring-after($key, '|'), '|')" /> 

    <xsl:element name="{$name}">
      <xsl:for-each select="key('kTagByName', concat(@id, '|', $key))">
        <!-- select 'attr1|somevalue1' - it's the attribute definition -->
        <xsl:variable name="attrDef" select="substring-after(@value, $key)" />
        <!-- create an attribute -->
        <xsl:attribute name="{substring-before($attrDef, '|')}">
          <xsl:value-of select="substring-after($attrDef, '|')" />
        </xsl:attribute>
      </xsl:for-each>
    </xsl:element>
  </xsl:template>

</xsl:stylesheet>

generates:

<Container>
  <TestTag>
    <object UID="T.A.uid1" name="uid1" />
    <tag1 attr1="somevalue1" attr2="somevalue2"></tag1>
    <tag2 attr3="somevalue3"></tag2>
  </TestTag>
  <TestTag>
    <object UID="T.A.uid2" name="uid2" />
    <tag1 attr1="somevalue4"></tag1>
    <tag2 attr3="somevalue5"></tag2>
  </TestTag>
</Container>

Note that this does not pay attention to duplicate attribute definitions. If you happen to have uid1|tag1|attr1|somevalue1 and later uid1|tag1|attr1|othervalue1, then you will end up with one attribute: attr1="othervalue1" because in the <xsl:for-each> both get their turn, and the latter one wins (i.e. ends up in the output).

请注意,这不会注意重复的属性定义。如果您碰巧有uid1 | tag1 | attr1 | somevalue1以及后来的uid1 | tag1 | attr1 | othervalue1,那么您最终会得到一个属性:attr1 =“othervalue1”因为在 中都得到轮到他们,后者获胜(即在输出中结束)。

It is possible to cater for that as well, it would require one more key and one more Muenchian grouping, I'm going to leave that as an exercise for the reader. Heh. ;)

也有可能迎合这一点,它需要一个更多的密钥和一个Muenchian分组,我将把它留给读者练习。嘿。 ;)