How to tidy-up Processing Instructions in Marklogic - xquery

Question

I have a content which is neither a valid HTML nor a XML in my legacy database. Considering the fact, it would be difficult to clean the legacy, I want to tidy this up in MarkLogic using xdmp:tidy. I am currently using ML-8.
<sub>
<p>
<???†?>
</p>
</sub>
I'm passing this content to tidy functionality in a way :
declare variable $xml as node() :=
<content>
<![CDATA[<p><???†?></p>]]>
</content>;
xdmp:tidy(xdmp:quote($xml//text()),
<options xmlns="xdmp:tidy">
<assume-xml-procins>yes</assume-xml-procins>
<quiet>yes</quiet>
<tidy-mark>no</tidy-mark>
<enclose-text>yes</enclose-text>
<indent>yes</indent>
</options>)
As a result it returns :
<p>
<? ?†?>
</p>
Now this result is not the valid xml format (I checked it via XML validator) due to which when I try to insert this XML into the MarkLogic it throws an error saying 'MALFORMED BODY | Invalid Processing Instruction names'.
I did some investigation around PIs but not much luck. I could have tried saving the content without PI but this is also not a valid PI too.

Answer 1

That is because what you think is a PI is in fact not a PI.
From W3C:
2.6 Processing Instructions
[Definition: Processing instructions (PIs) allow documents to contain
instructions for applications.]
Processing Instructions
[16] PI ::= '' Char*)))?
'?>'
[17] PITarget ::= Name - (('X' | 'x') ('M' | 'm') ('L' |
'l'))
So the PI name cannot start with ? as in your sample ??†
You probably want to clean up the content before you pass it to tidy.
Like below:
declare variable $xml as node() :=
<content><![CDATA[<p>Hello <???†?>world</p>]]></content>;
declare function local:copy($input as item()*) as item()* {
for $node in $input
return
typeswitch($node)
case text()
return fn:replace($node,"<\?[^>]+\?>","")
case element()
return
element {name($node)} {
(: output each attribute in this element :)
for $att in $node/#*
return
attribute {name($att)} {$att}
,
(: output all the sub-elements of this element recursively :)
for $child in $node
return local:copy($child/node())
}
(: otherwise pass it through. Used for text(), comments, and PIs :)
default return $node
};
xdmp:tidy(local:copy($xml),
<options xmlns="xdmp:tidy">
<assume-xml-procins>no</assume-xml-procins>
<quiet>yes</quiet>
<tidy-mark>no</tidy-mark>
<enclose-text>yes</enclose-text>
<indent>yes</indent>
</options>)
This would do the trick to get rid of all PIs (real and fake PIs)
Regards,
Peter