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

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

html:doc

Signature
html:doc(
  $href     as xs:string?,
  $options  as map(*)?     := map { }
) as document-node()?
Summary Fetches the HTML document referred to by the given $href, 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.

html:parse

Signature
html:parse(
  $value    as xs:anyAtomicType,
  $options  as map(*)?           := map { }
) as document-node()
Summary Converts the HTML document specified by $value to XML and returns a document node:
  • The input may be of type xs:string, xs:base64Binary, or xs:hexBinary.
  • If the input is passed on in its binary representation, and if no encoding option is supplied, the HTML parser will try to choose the correct encoding automatically.

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

Errors parse: the input cannot be converted to XML.

html:parser

Signature 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.

Examples

Basic Example

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

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

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

Code Description
parse The input cannot be converted to XML.

Changelog

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

The module was introduced with Version 7.6.