Injects UUIDs into a document.
<p:declare-step type="p:uuid"> <input port="source" primary="true" content-types="xml html" sequence="false"/> <output port="result" primary="true" content-types="text xml html" sequence="false"/> <option name="match" as="xs:string" required="false" select="'/*'"/> <option name="version" as="xs:integer?" required="false" select="()"/> </p:declare-step>
The p:uuid
step takes the document appearing on its source
port and replaces nodes matching the match
option
with a UUID.
Ports:
Type | Port | Primary? | Content types | Seq? | Description |
---|---|---|---|---|---|
|
|
|
|
| The document to inject the UUIDs in. |
|
|
|
|
| The resulting document. |
Options:
UUID stands for Universally Unique Identifier. It is also known as GUID, which stands for Globally Unique Identifier. A UUID is a 128-bit
value that is, for all practical purposes, worldwide unique. It is usually written as a 32-character hexadecimal value in a pattern using
hyphens, for example f81d4fae-7dec-11d0-a765-00a0c91e6bf6
. The Wikipedia page about UUIDs is here.
The p:uuid
step does the following:
It computes a single UUID, using the version
option. This UUID is
used for all replacements (so all replacements get the same value).
It takes the document appearing on its source
port and holds the XSLT selection pattern in the match
option against this.
For all matched nodes:
If the matched node is an attribute, the value of the attribute is replaced with the UUID.
If the document-node is matched, the full document will be replaced by UUID (and the result will therefore be a text document).
In all other cases, the full node is replaced by the UUID.
The following example replaces the text inside the <uuid>
elements with a generated UUID:
Source document:
<thing> <uuid>UUID</uuid> <uuid>UUID</uuid> </thing>
Pipeline document:
<p:declare-step xmlns:p="http://www.w3.org/ns/xproc" version="3.0"> <p:input port="source"/> <p:output port="result"/> <p:uuid match="/thing/uuid/text()"/> </p:declare-step>
Result document:
<thing> <uuid>cf7adad3-4218-458b-b71e-06ff7cfa8403</uuid> <uuid>cf7adad3-4218-458b-b71e-06ff7cfa8403</uuid> </thing>
Please notice that the UUIDs are identical, the same value is used for every replacement.
If the match
option matches an attribute, the value of the attribute is
replaced:
Source document:
<thing uuid=""/>
Pipeline document:
<p:declare-step xmlns:p="http://www.w3.org/ns/xproc" version="3.0"> <p:input port="source"/> <p:output port="result"/> <p:uuid match="/thing/@uuid"/> </p:declare-step>
Result document:
<thing uuid="f143d9d3-c27c-49be-ac19-ac40dba3c460"/>
p:uuid
preserves all document-properties of the document(s) appearing on its source
port.
There is one exception: if the resulting document contains only text, the content-type
document-property is changed to
text/plain
and the serialization
document-property is removed.
If an attribute called xml:base
is added or changed, the base URI of the element is updated accordingly. See also category
Base URI related.
Error code | Description |
---|---|
It is a dynamic error if the processor does not support the specified |
This description of the p:uuid
step is for XProc version: 3.0. This is a required step (an XProc 3.0 processor must support this).
The formal specification for the p:uuid
step can be found here.
The p:uuid
step is part of categories:
The p:uuid
step is also present in version:
3.1.