Scala: Parse HTML-fragment

Question

Our database stores HTML fragments like f.ex. <p>A.</p><p>B.</p>. I want to include the Html fragements from the database into a Lift snippet.

To do that, I tried to use the XML.loadString()-method to convert the fragement into a scala.xml.Elem, but this only works for full valid XML-documents:

import scala.xml.XML
@Test
def doesnotWork() {
  val result = XML.loadString("<p>A</p><p>B</p>")
  assert(result === <p>A</p><p>B</p>)
}

@Test
def thisWorks() {
  val result = XML.loadString("<test><p>A</p><p>B</p></test>")
  assert(result === <test><p>A</p><p>B</p></test>)
}

The test doesnotWork results in an exception:

org.xml.sax.SAXParseException; lineNumber: 1; columnNumber: 10; The markup in the document following the root element must be well-formed.

Is it possible to convert just (valid) fragements to XML?

Unless your fragments are XHTML, you will want to parse with Html5.parse. — leedm777
– leedm777, Commented Feb 21, 2012 at 14:47
And by parsing your own HTML, you are avoiding Lift's XSS protections. Be sure to sanitize your HTML before sending back to the browser. — leedm777
– leedm777, Commented Feb 21, 2012 at 14:50

leedm777 · Accepted Answer · 2012-02-21 14:44:49Z

5

Since you're using Lift, you can wrap your XML in lift:children as a workaround. The Children snippet simply returns the element's children; and is very useful for wrapping fragments you need to parse.

@Test
def thisAlsoWorks() {
  val result = XML.loadString("<lift:children><p>A</p><p>B</p></lift:children>")
  assert(result === <lift:children><p>A</p><p>B</p></lift:children>)
 }

answered Feb 21, 2012 at 14:44

leedm777

24.2k11 gold badges62 silver badges88 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Sonson Over a year ago

Thanks! I didn't know the Children snippet.

Philippe · Accepted Answer · 2012-02-21 12:33:35Z

3

You don't need a full valid XML document, but you do need a single top-level tag.

As you observed, the following works:

XML.loadString("<fragment><p>A</p><p>B</p></fragment>")

You could then either store a sequence of Elems, or wrap them in a custom tag and extract the sequence using .descendant.

answered Feb 21, 2012 at 12:33

Philippe

9,8225 gold badges41 silver badges60 bronze badges

1 Comment

Sonson Over a year ago

This also works - thank you. But I will use the simple Children-Snippet-workaround.

Collectives™ on Stack Overflow

Scala: Parse HTML-fragment

2 Answers 2

1 Comment

1 Comment

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

1 Comment

1 Comment

Your Answer

Sign up or log in

Post as a guest

Linked

Related