/**
* @param configuration the configuration to use for the cleaning
* @return the default {@link CleanerProperties} to be used for cleaning.
*/
private CleanerProperties getDefaultCleanerProperties(HTMLCleanerConfiguration configuration) {
CleanerProperties defaultProperties = new CleanerProperties();
defaultProperties.setOmitUnknownTags(true);
// HTML Cleaner uses the compact notation by default but we don't want that since:
// - it's more work and not required since not compact notation is valid XHTML
// - expanded elements can also be rendered fine in browsers that only support HTML.
defaultProperties.setUseEmptyElementTags(false);
// Wrap script and style content in CDATA blocks
defaultProperties.setUseCdataForScriptAndStyle(true);
// If the caller has defined NAMESPACE_AWARE configuration property then use it, otherwise use
// our default.
String param = configuration.getParameters().get(HTMLCleanerConfiguration.NAMESPACES_AWARE);
boolean namespacesAware = (param != null) ? Boolean.parseBoolean(param) : true;
defaultProperties.setNamespacesAware(namespacesAware);
return defaultProperties;
}
/** Verify that the restricted parameter works. */
@Test
public void restrictedHtml() throws ComponentLookupException {
HTMLCleanerConfiguration configuration =
this.mocker.getComponentUnderTest().getDefaultConfiguration();
Map<String, String> parameters = new HashMap<String, String>();
parameters.putAll(configuration.getParameters());
parameters.put("restricted", "true");
configuration.setParameters(parameters);
String result =
HTMLUtils.toString(
this.mocker
.getComponentUnderTest()
.clean(new StringReader("<script>alert(\"foo\")</script>"), configuration));
Assert.assertEquals(HEADER_FULL + "<pre>alert(\"foo\")</pre>" + FOOTER, result);
result =
HTMLUtils.toString(
this.mocker
.getComponentUnderTest()
.clean(new StringReader("<style>p {color:white;}</style>"), configuration));
Assert.assertEquals(HEADER_FULL + "<pre>p {color:white;}</pre>" + FOOTER, result);
}
/**
* @param configuration The cleaner configuration.
* @return the default cleaning transformations to perform on tags, in addition to the base
* transformations done by HTML Cleaner
*/
private CleanerTransformations getDefaultCleanerTransformations(
HTMLCleanerConfiguration configuration) {
CleanerTransformations defaultTransformations = new CleanerTransformations();
TagTransformation tt =
new TagTransformation(HTMLConstants.TAG_B, HTMLConstants.TAG_STRONG, false);
defaultTransformations.addTransformation(tt);
tt = new TagTransformation(HTMLConstants.TAG_I, HTMLConstants.TAG_EM, false);
defaultTransformations.addTransformation(tt);
tt = new TagTransformation(HTMLConstants.TAG_U, HTMLConstants.TAG_INS, false);
defaultTransformations.addTransformation(tt);
tt = new TagTransformation(HTMLConstants.TAG_S, HTMLConstants.TAG_DEL, false);
defaultTransformations.addTransformation(tt);
tt = new TagTransformation(HTMLConstants.TAG_STRIKE, HTMLConstants.TAG_DEL, false);
defaultTransformations.addTransformation(tt);
tt = new TagTransformation(HTMLConstants.TAG_CENTER, HTMLConstants.TAG_P, false);
tt.addAttributeTransformation(HTMLConstants.ATTRIBUTE_STYLE, "text-align:center");
defaultTransformations.addTransformation(tt);
String restricted = configuration.getParameters().get(HTMLCleanerConfiguration.RESTRICTED);
if ("true".equalsIgnoreCase(restricted)) {
tt = new TagTransformation(HTMLConstants.TAG_SCRIPT, HTMLConstants.TAG_PRE, false);
defaultTransformations.addTransformation(tt);
tt = new TagTransformation(HTMLConstants.TAG_STYLE, HTMLConstants.TAG_PRE, false);
defaultTransformations.addTransformation(tt);
}
return defaultTransformations;
}
@Override
public Document clean(Reader originalHtmlContent, HTMLCleanerConfiguration configuration) {
Document result;
// Note: Instantiation of an HtmlCleaner object is cheap so there's no need to cache an instance
// of it,
// especially since this makes it extra safe with regards to multithreading (even though HTML
// Cleaner is
// already supposed to be thread safe).
CleanerProperties cleanerProperties = getDefaultCleanerProperties(configuration);
HtmlCleaner cleaner = new HtmlCleaner(cleanerProperties);
cleaner.setTransformations(getDefaultCleanerTransformations(configuration));
TagNode cleanedNode;
try {
cleanedNode = cleaner.clean(originalHtmlContent);
} catch (Exception e) {
// This shouldn't happen since we're not doing any IO... I consider this a flaw in the design
// of HTML
// Cleaner.
throw new RuntimeException("Unhandled error when cleaning HTML", e);
}
// Serialize the cleanedNode TagNode into a w3c dom. Ideally following code should be enough.
// But SF's HTML Cleaner seems to omit the DocType declaration while serializing.
// See
// https://sourceforge.net/tracker/index.php?func=detail&aid=2062318&group_id=183053&atid=903696
// cleanedNode.setDocType(new DoctypeToken("html", "PUBLIC", "-//W3C//DTD XHTML 1.0
// Strict//EN",
// "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"));
// try {
// result = new DomSerializer(cleanerProperties, false).createDOM(cleanedNode);
// } catch(ParserConfigurationException ex) { }
// As a workaround, we must serialize the cleanedNode into a temporary w3c document, create a
// new w3c document
// with proper DocType declaration and move the root node from the temporary document to the new
// one.
try {
// Since there's a bug in SF's HTML Cleaner in that it doesn't recognize CDATA blocks we need
// to turn off
// character escaping (hence the false value passed) and do the escaping in
// XMLUtils.toString(). Note that
// this can cause problem for code not serializing the W3C DOM to a String since it won't have
// the
// characters escaped.
// See
// https://sourceforge.net/tracker/index.php?func=detail&aid=2691888&group_id=183053&atid=903696
Document tempDoc = new XWikiDOMSerializer(cleanerProperties, false).createDOM(cleanedNode);
DOMImplementation domImpl =
DocumentBuilderFactory.newInstance().newDocumentBuilder().getDOMImplementation();
DocumentType docType =
domImpl.createDocumentType(
QUALIFIED_NAME_HTML,
"-//W3C//DTD XHTML 1.0 Strict//EN",
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd");
result = domImpl.createDocument(null, QUALIFIED_NAME_HTML, docType);
result.replaceChild(
result.adoptNode(tempDoc.getDocumentElement()), result.getDocumentElement());
} catch (ParserConfigurationException ex) {
throw new RuntimeException("Error while serializing TagNode into w3c dom.", ex);
}
// Finally apply filters.
for (HTMLFilter filter : configuration.getFilters()) {
filter.filter(result, configuration.getParameters());
}
return result;
}
