所以基本上我尝试使用 thymeleaf 使用 ld+json 构建动态模式。为了检索相应页面的 url，我们设置了一个自定义处理器：
public class QuackUrlAttributeTagProcessor extends AbstractAttributeTagProcessor {
private static final String ATTR_NAME = "quackToHref";
private static final int PRECEDENCE = 10000;
@Autowired
private ApplicationPropertyAccess applicationProperties;
/**
* Constructs a new processor.
*
* @param dialectPrefix the prefix to use if not the standard defined by the dialect
*/
public QuackUrlAttributeTagProcessor(final String dialectPrefix) {
super(
TemplateMode.HTML, // This processor will apply only to HTML mode
dialectPrefix, // Prefix to be applied to name for matching
null, // No tag name: match any tag name
false, // No prefix to be applied to tag name
ATTR_NAME, // Name of the attribute that will be matched
true, // Apply dialect prefix to attribute name
PRECEDENCE, // Precedence (inside dialect's precedence)
true); // Remove the matched attribute afterwards
}
/**
* Performs the actual task of the processor. This will use quack data to construct an Url path.
*/
@Override
protected void doProcess(final ITemplateContext context, final IProcessableElementTag tag,
final AttributeName attributeName, final String attributeValue,
final IElementTagStructureHandler structureHandler) {
IEngineConfiguration configuration = context.getConfiguration();
IStandardExpressionParser parser = StandardExpressions.getExpressionParser(configuration);
IStandardExpression expression = parser.parseExpression(context, attributeValue);
Quack quack = (Quack)expression.execute(context);
String url = QuackManager.buildUrlPath(quack);
structureHandler.setAttribute("href", applicationProperties.getFrontendBaseUrl() + url);
}
}
这样我就可以在 html 模板中添加属性，如下所示：
<html xmlns:th="http://www.thymeleaf.org" xmlns:xc="http://www.example.de">
<link rel="canonical" xc:quackToHref="${quack}" />
正确设置 href 属性。现在 ld+json 脚本如下所示：
<script type="application/ld+json">
/*<![CDATA[*/
{
"@context": "https://schema.org",
"@graph": [
{
"@type": "Article",
"url": "[[xc:quackToHref="${quack}"]]",
"isPartOf": { "@id": "test" },
"author": {
"name": "[[${article.nickname}]]",
"@id": "https://example.de/profile/[[${article.authorId}]]"
},
},
]
}
/*]]>*/
</script>
什么引发了错误：
Caused by: org.attoparser.ParseException: Could not parse as expression: "xc:quackToHref="${quack}" (template: "articlequack" - line 38, col 22)
显然，无法在脚本内调用自定义处理器。有谁知道如何获取CDATA中的url？
如果您想在文本模板模式中使用属性，语法应如下所示：
[# xc:quackToHref="${quack}" /]