Thymeleaf 无法解析多模块SpringBoot项目中的模板

Question

我有标题中描述的问题。

我创建了具有以下结构的多模块 SpringBoot 项目：

• 父模块（pom 封装）
  • 前端模块（jar 包装）
  • business-module（jar包）
  • 运行模块（战争包装）

当我通过 IntelliJ 直接运行应用程序时它工作正常，但是当我通过 Maven 构建 package 并在控制台创建的 run-module.war 文件中运行时它抛出：

org.thymeleaf.exceptions.TemplateInputException: Error resolving template [pages/example-page], template might not exist or might not be accessible by any of the configured Template Resolvers
    at org.thymeleaf.engine.TemplateManager.resolveTemplate(TemplateManager.java:869) ~[thymeleaf-3.0.11.RELEASE.jar!/:3.0.11.RELEASE]
    at org.thymeleaf.engine.TemplateManager.parseAndProcess(TemplateManager.java:607) ~[thymeleaf-3.0.11.RELEASE.jar!/:3.0.11.RELEASE]
    at org.thymeleaf.TemplateEngine.process(TemplateEngine.java:1098) ~[thymeleaf-3.0.11.RELEASE.jar!/:3.0.11.RELEASE]
    at org.thymeleaf.TemplateEngine.process(TemplateEngine.java:1072) ~[thymeleaf-3.0.11.RELEASE.jar!/:3.0.11.RELEASE]
    at org.thymeleaf.spring5.view.ThymeleafView.renderFragment(ThymeleafView.java:362) ~[thymeleaf-spring5-3.0.11.RELEASE.jar!/:3.0.11.RELEASE]
    at org.thymeleaf.spring5.view.ThymeleafView.render(ThymeleafView.java:189) ~[thymeleaf-spring5-3.0.11.RELEASE.jar!/:3.0.11.RELEASE]
    at org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1373) ~[spring-webmvc-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
    at org.springframework.web.servlet.DispatcherServlet.processDispatchResult(DispatcherServlet.java:1118) ~[spring-webmvc-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1057) ~[spring-webmvc-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:943) ~[spring-webmvc-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006) ~[spring-webmvc-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
    at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898) ~[spring-webmvc-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:634) ~[tomcat-embed-core-9.0.29.jar!/:9.0.29]
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883) ~[spring-webmvc-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:741) ~[tomcat-embed-core-9.0.29.jar!/:9.0.29]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) ~[tomcat-embed-core-9.0.29.jar!/:9.0.29]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.29.jar!/:9.0.29]
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) ~[tomcat-embed-websocket-9.0.29.jar!/:9.0.29]
...

我可以看到在 run-module.war 里面有一个 front-module.jar 作为 lib。

任何人都知道如何“告诉”Thymeleaf 模板在哪里？

Answer 1

我通过以下配置解决了问题，创建一个 ClassLoaderTemplateResolver 很重要：

@Configuration
public class ThymeleafConfiguration {

    @Bean
    public ClassLoaderTemplateResolver thymeleafTemplateResolver() {

        ClassLoaderTemplateResolver resolver = new ClassLoaderTemplateResolver();
        resolver.setPrefix("/templates/");
        resolver.setSuffix(".html");
        resolver.setCacheable(false);
        resolver.setCharacterEncoding("UTF-8");
        resolver.setTemplateMode(TemplateMode.HTML);
        return resolver;
    }

    @Bean
    public SpringTemplateEngine templateEngine() {

        SpringTemplateEngine templateEngine = new SpringTemplateEngine();
        templateEngine.setTemplateResolver(thymeleafTemplateResolver());
        return templateEngine;
    }

    @Bean
    public ThymeleafViewResolver thymeleafViewResolver() {

        ThymeleafViewResolver viewResolver = new ThymeleafViewResolver();
        viewResolver.setTemplateEngine(templateEngine());
        viewResolver.setCharacterEncoding("UTF-8");
        return viewResolver;
    }
}

Answer 2

在没有 jar 文件名的情况下将协议“classpath”添加到您的前缀中

spring.thymeleaf.prefix=classpath:/templates/

Answer 3

对于寻找更多潜在问题的人：

对我们来说，问题是使用了一个不正确的 class 加载器来检索资源，它似乎没有看到任何资源。 这是使用异步 CompletableFuture 的副作用。

我们的解决方法是从创建 CompletableFuture object 的线程中重用类加载器。

var classLoader = Thread.currentThread().getContextClassLoader();
CompletableFuture<Object> future = CompletableFuture.supplyAsync(() -> {
    Thread.currentThread().setContextClassLoader(classLoader);
    someAction();
});