Merge pull request quarkusio#43775 from mkouba/issue-41932

Qute: add Singleton scope to a Named Java record

docs/src/main/asciidoc/qute-reference.adoc

@@ -1710,15 +1710,31 @@ A CDI bean annotated with `@Named` can be referenced in any template through `cd
 NOTE: `@Named @Dependent` beans are shared across all expressions in a template for a single rendering operation, and destroyed after the rendering finished.
 
 All expressions with `cdi` and `inject` namespaces are validated during build.
-
 For the expression `cdi:personService.findPerson(10).name`, the implementation class of the injected bean must either declare the `findPerson` method or a matching <<template_extension_methods,template extension method>> must exist.
-
 For the expression `inject:foo.price`, the implementation class of the injected bean must either have the `price` property (e.g. a `getPrice()` method) or a matching <<template_extension_methods,template extension method>> must exist.
 
 NOTE: A `ValueResolver` is also generated for all beans annotated with `@Named` so that it's possible to access its properties without reflection.
 
 TIP: If your application serves xref:http-reference.adoc[HTTP requests] you can also inject the current `io.vertx.core.http.HttpServerRequest` via the `inject` namespace, e.g. `{inject:vertxRequest.getParam('foo')}`.
 
+Sometimes it may be necessary to access public methods and properties of a CDI bean that is not annotated with `@Named`.
+However, if you don't control the source of the bean it is not possible to add the `@Named` annotation.
+Nevertheless, it is possible to create an intermediate CDI bean annotated with `@Named`.
+This intermediate bean can inject the bean in question and make it accessible. 
+A Java record is a very convenient way to define such an intermediate CDI bean.
+
+[source,java]
+----
+@Named <1> <2>
+public record UserData(UserInfo info, @LoggedIn String username) { <3>
+}
+----
+<1> If no name is explicitly specified by the `value` member the https://jakarta.ee/specifications/cdi/4.1/jakarta-cdi-spec-4.1#default_name[default name is assigned] - the simple name of the bean class, after converting the first character to lower case. In this particular case, the default name is `userData`.
+<2> The `@Singleton` scope is added automatically.
+<3> All parameters of the canonical constructor are injection points. The accessor methods can be used to obtain the injected bean.
+
+And then in a template you can simply use `{cdi:userData.info}` or `{cdi:userData.username}`.
+
 [[typesafe_expressions]]
 === Type-safe Expressions
 

extensions/qute/deployment/src/main/java/io/quarkus/qute/deployment/QuteProcessor.java

@@ -38,6 +38,7 @@
 import java.util.regex.Pattern;
 import java.util.stream.Collectors;
 
+import jakarta.inject.Named;
 import jakarta.inject.Singleton;
 
 import org.jboss.jandex.AnnotationInstance;
@@ -60,6 +61,7 @@
 import org.jboss.logging.Logger;
 
 import io.quarkus.arc.deployment.AdditionalBeanBuildItem;
+import io.quarkus.arc.deployment.AutoAddScopeBuildItem;
 import io.quarkus.arc.deployment.BeanArchiveIndexBuildItem;
 import io.quarkus.arc.deployment.BeanContainerBuildItem;
 import io.quarkus.arc.deployment.BeanDefiningAnnotationBuildItem;
@@ -3338,6 +3340,20 @@ void validateTemplateDataNamespaces(List<TemplateDataBuildItem> templateData,
         }
     }
 
+    @BuildStep
+    AutoAddScopeBuildItem addSingletonToNamedRecords() {
+        return AutoAddScopeBuildItem.builder()
+                .isAnnotatedWith(DotName.createSimple(Named.class))
+                .and(this::isRecord)
+                .defaultScope(BuiltinScope.SINGLETON)
+                .reason("Found Java record annotated with @Named")
+                .build();
+    }
+
+    private boolean isRecord(ClassInfo clazz, Collection<AnnotationInstance> annotations, IndexView index) {
+        return clazz.isRecord();
+    }
+
     static Map<TemplateAnalysis, Set<Expression>> collectNamespaceExpressions(TemplatesAnalysisBuildItem analysis,
             String namespace) {
         Map<TemplateAnalysis, Set<Expression>> namespaceExpressions = new HashMap<>();

extensions/qute/deployment/src/test/java/io/quarkus/qute/deployment/inject/NamedRecordTest.java

@@ -0,0 +1,52 @@
+package io.quarkus.qute.deployment.inject;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.util.List;
+
+import jakarta.enterprise.inject.Produces;
+import jakarta.inject.Inject;
+import jakarta.inject.Named;
+import jakarta.inject.Singleton;
+
+import org.jboss.shrinkwrap.api.asset.StringAsset;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
+
+import io.quarkus.qute.Engine;
+import io.quarkus.test.QuarkusUnitTest;
+
+public class NamedRecordTest {
+
+    @RegisterExtension
+    static final QuarkusUnitTest config = new QuarkusUnitTest()
+            .withApplicationRoot(root -> root
+                    .addClasses(Beans.class, ListProducer.class)
+                    .addAsResource(
+                            new StringAsset(
+                                    "{#each cdi:beans.names}{it}::{/each}"),
+                            "templates/foo.html"));
+
+    @Inject
+    Engine engine;
+
+    @Test
+    public void testResult() {
+        assertEquals("Jachym::Vojtech::Ondrej::", engine.getTemplate("foo").render());
+    }
+
+    // @Singleton is added automatically
+    @Named
+    public record Beans(List<String> names) {
+    }
+
+    @Singleton
+    public static class ListProducer {
+
+        @Produces
+        List<String> names() {
+            return List.of("Jachym", "Vojtech", "Ondrej");
+        }
+    }
+
+}