HTML Module

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This XQuery Module provides functions for converting HTML to XML. Conversion will only take place if TagSoup is included in the classpath (see HTML Parsing for more details).

Conventions[edit]

All functions and errors in this module are assigned to the http://basex.org/modules/html namespace, which is statically bound to the html prefix.

Functions[edit]

html:parser[edit]

Signatures html:parser() as xs:string
Summary Returns the name of the applied HTML parser (currently: TagSoup). If an empty string is returned, TagSoup was not found in the classpath, and the input will be treated as well-formed XML.

html:parse[edit]

Signatures html:parse($input as xs:anyAtomicType) as document-node()
html:parse($input as xs:anyAtomicType, $options as map(*)?) as document-node()
Summary Converts the HTML document specified by $input to XML and returns a document node:
  • The input may either be a string or a binary item (xs:hexBinary, xs:base64Binary).
  • If the input is passed on in its binary representation, the HTML parser will try to automatically choose the correct encoding.

The $options argument can be used to set TagSoup Options.

Errors parse: the input cannot be converted to XML.

html:doc[edit]

Introduced with BaseX 9.4:

Signatures html:doc($uri as xs:string?) as document-node()?
html:doc($uri as xs:string?, $options as map(*)?) as document-node()?
Summary Fetches the HTML document referred to by the given $uri, converts it to XML and returns a document node. The $options argument can be used to set TagSoup Options.
Errors parse: the input cannot be converted to XML.

Examples[edit]

Basic Example[edit]

The following query converts the specified string to an XML document node.

Query
html:parse("<html>")
Result
<html xmlns="http://www.w3.org/1999/xhtml"/>

Specifying Options[edit]

The next query creates an XML document with namespaces:

Query
html:parse("<a href='ok.html'/>", map { 'nons': false() })
Result
<html xmlns="http://www.w3.org/1999/xhtml">
  <body>
    <a shape="rect" href="ok.html"/>
  </body>
</html>

Parsing Binary Input[edit]

If the input encoding is unknown, the data to be processed can be passed on in its binary representation. The HTML parser will automatically try to detect the correct encoding:

Query
html:parse(fetch:binary("https://en.wikipedia.org"))
Result
<html xmlns="http://www.w3.org/1999/xhtml" class="client-nojs" dir="ltr" lang="en">
  <head>
    <title>Wikipedia, the free encyclopedia</title>
    <meta charset="UTF-8"/>
    ...

Errors[edit]

Code Description
parse The input cannot be converted to XML.

Changelog[edit]

Version 9.4
Version 9.0
  • Updated: error codes updated; errors now use the module namespace

The module was introduced with Version 7.6.