Allow users to enable moderation for @RegisterAiService

core/deployment/src/main/java/io/quarkiverse/langchain4j/deployment/AiServicesProcessor.java

@@ -153,11 +153,13 @@ public void nativeSupport(CombinedIndexBuildItem indexBuildItem,
     @BuildStep
     public void findDeclarativeServices(CombinedIndexBuildItem indexBuildItem,
             BuildProducer<RequestChatModelBeanBuildItem> requestChatModelBeanProducer,
+            BuildProducer<RequestModerationModelBeanBuildItem> requestModerationModelBeanProducer,
             BuildProducer<DeclarativeAiServiceBuildItem> declarativeAiServiceProducer,
             BuildProducer<ReflectiveClassBuildItem> reflectiveClassProducer) {
         IndexView index = indexBuildItem.getIndex();
 
         boolean needChatModelBean = false;
+        boolean needModerationModelBean = false;
         for (AnnotationInstance instance : index.getAnnotations(Langchain4jDotNames.REGISTER_AI_SERVICES)) {
             if (instance.target().kind() != AnnotationTarget.Kind.CLASS) {
                 continue; // should never happen
@@ -208,11 +210,24 @@ public void findDeclarativeServices(CombinedIndexBuildItem indexBuildItem,
                 }
             }
 
-            DotName auditServiceClassSupplierName = Langchain4jDotNames.BEAN_IF_EXISTS_AUDIT_SERVICE_SUPPLIER;
-            AnnotationValue auditServiceClassSupplierValue = instance.value("auditServiceSupplier");
-            if (auditServiceClassSupplierValue != null) {
-                auditServiceClassSupplierName = auditServiceClassSupplierValue.asClass().name();
-                validateSupplierAndRegisterForReflection(auditServiceClassSupplierName, index, reflectiveClassProducer);
+            DotName auditServiceSupplierClassName = Langchain4jDotNames.BEAN_IF_EXISTS_AUDIT_SERVICE_SUPPLIER;
+            AnnotationValue auditServiceSupplierValue = instance.value("auditServiceSupplier");
+            if (auditServiceSupplierValue != null) {
+                auditServiceSupplierClassName = auditServiceSupplierValue.asClass().name();
+                validateSupplierAndRegisterForReflection(auditServiceSupplierClassName, index, reflectiveClassProducer);
+            }
+
+            DotName moderationModelSupplierClassName = null;
+            AnnotationValue moderationModelSupplierValue = instance.value("moderationModelSupplier");
+            if (moderationModelSupplierValue != null) {
+                moderationModelSupplierClassName = moderationModelSupplierValue.asClass().name();
+                if (Langchain4jDotNames.NO_MODERATION_MODEL_SUPPLIER.equals(moderationModelSupplierClassName)) {
+                    moderationModelSupplierClassName = null;
+                } else if (Langchain4jDotNames.BEAN_MODERATION_MODEL_SUPPLIER.equals(moderationModelSupplierClassName)) {
+                    needModerationModelBean = true;
+                } else {
+                    validateSupplierAndRegisterForReflection(moderationModelSupplierClassName, index, reflectiveClassProducer);
+                }
             }
 
             BuiltinScope declaredScope = BuiltinScope.from(declarativeAiServiceClassInfo);
@@ -225,13 +240,17 @@ public void findDeclarativeServices(CombinedIndexBuildItem indexBuildItem,
                             toolDotNames,
                             chatMemoryProviderSupplierClassDotName,
                             retrieverSupplierClassDotName,
-                            auditServiceClassSupplierName,
+                            auditServiceSupplierClassName,
+                            moderationModelSupplierClassName,
                             cdiScope));
         }
 
         if (needChatModelBean) {
             requestChatModelBeanProducer.produce(new RequestChatModelBeanBuildItem());
         }
+        if (needModerationModelBean) {
+            requestModerationModelBeanProducer.produce(new RequestModerationModelBeanBuildItem());
+        }
     }
 
     private void validateSupplierAndRegisterForReflection(DotName supplierDotName, IndexView index,
@@ -262,6 +281,7 @@ public void handleDeclarativeServices(AiServicesRecorder recorder,
         boolean needsChatMemoryProviderBean = false;
         boolean needsRetrieverBean = false;
         boolean needsAuditServiceBean = false;
+        boolean needsModerationModelBean = false;
         Set<DotName> allToolNames = new HashSet<>();
 
         for (DeclarativeAiServiceBuildItem bi : declarativeAiServiceItems) {
@@ -286,13 +306,18 @@ public void handleDeclarativeServices(AiServicesRecorder recorder,
                     ? bi.getAuditServiceClassSupplierDotName().toString()
                     : null;
 
+            String moderationModelSupplierClassName = (bi.getModerationModelSupplierDotName() != null
+                    ? bi.getModerationModelSupplierDotName().toString()
+                    : null);
+
             SyntheticBeanBuildItem.ExtendedBeanConfigurator configurator = SyntheticBeanBuildItem
                     .configure(declarativeAiServiceClassInfo.name())
                     .createWith(recorder.createDeclarativeAiService(
                             new DeclarativeAiServiceCreateInfo(serviceClassName, chatLanguageModelSupplierClassName,
                                     toolClassNames, chatMemoryProviderSupplierClassName,
                                     retrieverSupplierClassName,
-                                    auditServiceClassSupplierName)))
+                                    auditServiceClassSupplierName,
+                                    moderationModelSupplierClassName)))
                     .destroyer(DeclarativeAiServiceBeanDestroyer.class)
                     .setRuntimeInit()
                     .scope(bi.getCdiScope());
@@ -333,6 +358,11 @@ public void handleDeclarativeServices(AiServicesRecorder recorder,
                 needsAuditServiceBean = true;
             }
 
+            if (Langchain4jDotNames.BEAN_MODERATION_MODEL_SUPPLIER.toString().equals(moderationModelSupplierClassName)) {
+                configurator.addInjectionPoint(ClassType.create(Langchain4jDotNames.MODERATION_MODEL));
+                needsModerationModelBean = true;
+            }
+
             syntheticBeanProducer.produce(configurator.done());
         }
 
@@ -348,6 +378,9 @@ public void handleDeclarativeServices(AiServicesRecorder recorder,
         if (needsAuditServiceBean) {
             unremoveableProducer.produce(UnremovableBeanBuildItem.beanTypes(Langchain4jDotNames.AUDIT_SERVICE));
         }
+        if (needsModerationModelBean) {
+            unremoveableProducer.produce(UnremovableBeanBuildItem.beanTypes(Langchain4jDotNames.MODERATION_MODEL));
+        }
         if (!allToolNames.isEmpty()) {
             unremoveableProducer.produce(UnremovableBeanBuildItem.beanTypes(allToolNames));
         }

core/deployment/src/main/java/io/quarkiverse/langchain4j/deployment/BeansProcessor.java

@@ -49,6 +49,7 @@ public void handleProviders(BeanDiscoveryFinishedBuildItem beanDiscoveryFinished
             List<EmbeddingModelProviderCandidateBuildItem> embeddingCandidateItems,
             List<ModerationModelProviderCandidateBuildItem> moderationCandidateItems,
             List<RequestChatModelBeanBuildItem> requestChatModelBeanItems,
+            List<RequestModerationModelBeanBuildItem> requestModerationModelBeanBuildItems,
             LangChain4jBuildConfig buildConfig,
             BuildProducer<SelectedChatModelProviderBuildItem> selectedChatProducer,
             BuildProducer<SelectedEmbeddingModelCandidateBuildItem> selectedEmbeddingProducer,
@@ -74,6 +75,9 @@ public void handleProviders(BeanDiscoveryFinishedBuildItem beanDiscoveryFinished
         if (!requestChatModelBeanItems.isEmpty()) {
             chatModelBeanRequested = true;
         }
+        if (!requestModerationModelBeanBuildItems.isEmpty()) {
+            moderationModelBeanRequested = true;
+        }
 
         if (chatModelBeanRequested || streamingChatModelBeanRequested) {
             selectedChatProducer.produce(

core/deployment/src/main/java/io/quarkiverse/langchain4j/deployment/DeclarativeAiServiceBuildItem.java

@@ -20,20 +20,23 @@ public final class DeclarativeAiServiceBuildItem extends MultiBuildItem {
     private final DotName chatMemoryProviderSupplierClassDotName;
     private final DotName retrieverSupplierClassDotName;
     private final DotName auditServiceClassSupplierDotName;
+    private final DotName moderationModelSupplierDotName;
     private final ScopeInfo cdiScope;
 
     public DeclarativeAiServiceBuildItem(ClassInfo serviceClassInfo, DotName languageModelSupplierClassDotName,
             List<DotName> toolDotNames,
             DotName chatMemoryProviderSupplierClassDotName,
             DotName retrieverSupplierClassDotName,
             DotName auditServiceClassSupplierDotName,
+            DotName moderationModelSupplierDotName,
             ScopeInfo cdiScope) {
         this.serviceClassInfo = serviceClassInfo;
         this.languageModelSupplierClassDotName = languageModelSupplierClassDotName;
         this.toolDotNames = toolDotNames;
         this.chatMemoryProviderSupplierClassDotName = chatMemoryProviderSupplierClassDotName;
         this.retrieverSupplierClassDotName = retrieverSupplierClassDotName;
         this.auditServiceClassSupplierDotName = auditServiceClassSupplierDotName;
+        this.moderationModelSupplierDotName = moderationModelSupplierDotName;
         this.cdiScope = cdiScope;
     }
 
@@ -61,6 +64,10 @@ public DotName getAuditServiceClassSupplierDotName() {
         return auditServiceClassSupplierDotName;
     }
 
+    public DotName getModerationModelSupplierDotName() {
+        return moderationModelSupplierDotName;
+    }
+
     public ScopeInfo getCdiScope() {
         return cdiScope;
     }

core/deployment/src/main/java/io/quarkiverse/langchain4j/deployment/Langchain4jDotNames.java

@@ -61,4 +61,10 @@ public class Langchain4jDotNames {
     static final DotName BEAN_IF_EXISTS_AUDIT_SERVICE_SUPPLIER = DotName.createSimple(
             RegisterAiService.BeanIfExistsAuditServiceSupplier.class);
 
+    static final DotName BEAN_MODERATION_MODEL_SUPPLIER = DotName.createSimple(
+            RegisterAiService.BeanModerationModelSupplier.class);
+
+    static final DotName NO_MODERATION_MODEL_SUPPLIER = DotName.createSimple(
+            RegisterAiService.NoModerationModelSupplier.class);
+
 }

core/deployment/src/main/java/io/quarkiverse/langchain4j/deployment/RequestChatModelBeanBuildItem.java

@@ -4,7 +4,7 @@
 
 /**
  * Allows extension to request the creation of a {@link dev.langchain4j.model.chat.ChatLanguageModel} bean
- * even if no injection point
+ * even if no injection point exists.
  */
 public final class RequestChatModelBeanBuildItem extends MultiBuildItem {
 }

core/deployment/src/main/java/io/quarkiverse/langchain4j/deployment/RequestModerationModelBeanBuildItem.java

@@ -0,0 +1,10 @@
+package io.quarkiverse.langchain4j.deployment;
+
+import io.quarkus.builder.item.MultiBuildItem;
+
+/**
+ * Allows extension to request the creation of a {@link dev.langchain4j.model.moderation.ModerationModel} bean
+ * even if no injection point exists.
+ */
+public final class RequestModerationModelBeanBuildItem extends MultiBuildItem {
+}

core/runtime/src/main/java/io/quarkiverse/langchain4j/RegisterAiService.java

@@ -12,6 +12,7 @@
 import dev.langchain4j.memory.chat.ChatMemoryProvider;
 import dev.langchain4j.memory.chat.MessageWindowChatMemory;
 import dev.langchain4j.model.chat.ChatLanguageModel;
+import dev.langchain4j.model.moderation.ModerationModel;
 import dev.langchain4j.retriever.Retriever;
 import dev.langchain4j.service.AiServices;
 import dev.langchain4j.store.memory.chat.ChatMemoryStore;
@@ -73,7 +74,7 @@
 
     /**
      * Configures the way to obtain the {@link Retriever} to use (when using RAG).
-     * By default, no chat memory is used.
+     * By default, no supplier is used.
      * If a CDI bean of type {@link ChatMemory} is needed, the value should be {@link BeanRetrieverSupplier}.
      * If an arbitrary {@link ChatMemory} instance is needed, a custom implementation of {@link Supplier<ChatMemory>}
      * needs to be provided.
@@ -89,6 +90,15 @@
      */
     Class<? extends Supplier<AuditService>> auditServiceSupplier() default BeanIfExistsAuditServiceSupplier.class;
 
+    /**
+     * Configures the way to obtain the {@link ModerationModel} to use.
+     * By default, no moderation model is used.
+     * If a CDI bean of type {@link ChatMemory} is needed, the value should be {@link BeanRetrieverSupplier}.
+     * If an arbitrary {@link ChatMemory} instance is needed, a custom implementation of {@link Supplier<ChatMemory>}
+     * needs to be provided.
+     */
+    Class<? extends Supplier<ModerationModel>> moderationModelSupplier() default NoModerationModelSupplier.class;
+
     /**
      * Marker that is used to tell Quarkus to use the {@link ChatLanguageModel} that has been configured as a CDI bean by
      * any of the extensions providing such capability (such as {@code quarkus-langchain4j-openai} and
@@ -162,4 +172,28 @@ public AuditService get() {
             throw new UnsupportedOperationException("should never be called");
         }
     }
+
+    /**
+     * Marker that is used to tell Quarkus to use the {@link ModerationModel} that has been configured as a CDI bean by
+     * any of the extensions providing such capability (such as {@code quarkus-langchain4j-openai} and
+     * {@code quarkus-langchain4j-azure-openai}).
+     */
+    final class BeanModerationModelSupplier implements Supplier<ModerationModel> {
+
+        @Override
+        public ModerationModel get() {
+            throw new UnsupportedOperationException("should never be called");
+        }
+    }
+
+    /**
+     * Marker class to indicate that no moderation model should be used
+     */
+    final class NoModerationModelSupplier implements Supplier<ModerationModel> {
+
+        @Override
+        public ModerationModel get() {
+            throw new UnsupportedOperationException("should never be called");
+        }
+    }
 }

core/runtime/src/main/java/io/quarkiverse/langchain4j/runtime/AiServicesRecorder.java

@@ -16,6 +16,7 @@
 import dev.langchain4j.data.segment.TextSegment;
 import dev.langchain4j.memory.chat.ChatMemoryProvider;
 import dev.langchain4j.model.chat.ChatLanguageModel;
+import dev.langchain4j.model.moderation.ModerationModel;
 import dev.langchain4j.retriever.Retriever;
 import io.quarkiverse.langchain4j.RegisterAiService;
 import io.quarkiverse.langchain4j.audit.AuditService;
@@ -28,9 +29,6 @@
 
 @Recorder
 public class AiServicesRecorder {
-
-    private static final TypeLiteral<Instance<ChatMemoryProvider>> CHAT_MEMORY_PROVIDER_INSTANCE_TYPE_LITERAL = new TypeLiteral<>() {
-    };
     private static final TypeLiteral<Instance<Retriever<TextSegment>>> RETRIEVER_INSTANCE_TYPE_LITERAL = new TypeLiteral<>() {
 
     };
@@ -151,6 +149,21 @@ public T apply(SyntheticCreationalContext<T> creationalContext) {
                         }
                     }
 
+                    if (info.getModerationModelSupplierClassName() != null) {
+                        if (RegisterAiService.BeanModerationModelSupplier.class.getName()
+                                .equals(info.getModerationModelSupplierClassName())) {
+                            ModerationModel moderationModel = creationalContext.getInjectedReference(ModerationModel.class);
+                            quarkusAiServices.moderationModel(moderationModel);
+                        } else {
+                            @SuppressWarnings("rawtypes")
+                            Supplier<? extends AuditService> supplier = (Supplier<? extends AuditService>) Thread
+                                    .currentThread().getContextClassLoader()
+                                    .loadClass(info.getModerationModelSupplierClassName())
+                                    .getConstructor().newInstance();
+                            quarkusAiServices.auditService(supplier.get());
+                        }
+                    }
+
                     return (T) quarkusAiServices.build();
                 } catch (ClassNotFoundException e) {
                     throw new IllegalStateException(e);

core/runtime/src/main/java/io/quarkiverse/langchain4j/runtime/aiservice/DeclarativeAiServiceCreateInfo.java

@@ -13,18 +13,21 @@ public class DeclarativeAiServiceCreateInfo {
     private final String retrieverSupplierClassName;
 
     private final String auditServiceClassSupplierName;
+    private final String moderationModelSupplierClassName;
 
     @RecordableConstructor
     public DeclarativeAiServiceCreateInfo(String serviceClassName, String languageModelSupplierClassName,
             List<String> toolsClassNames, String chatMemoryProviderSupplierClassName,
             String retrieverSupplierClassName,
-            String auditServiceClassSupplierName) {
+            String auditServiceClassSupplierName,
+            String moderationModelSupplierClassName) {
         this.serviceClassName = serviceClassName;
         this.languageModelSupplierClassName = languageModelSupplierClassName;
         this.toolsClassNames = toolsClassNames;
         this.chatMemoryProviderSupplierClassName = chatMemoryProviderSupplierClassName;
         this.retrieverSupplierClassName = retrieverSupplierClassName;
         this.auditServiceClassSupplierName = auditServiceClassSupplierName;
+        this.moderationModelSupplierClassName = moderationModelSupplierClassName;
     }
 
     public String getServiceClassName() {
@@ -50,4 +53,8 @@ public String getRetrieverSupplierClassName() {
     public String getAuditServiceClassSupplierName() {
         return auditServiceClassSupplierName;
     }
+
+    public String getModerationModelSupplierClassName() {
+        return moderationModelSupplierClassName;
+    }
 }

docs/modules/ROOT/pages/ai-services.adoc

@@ -275,6 +275,34 @@ A document retriever fetches data from an external source and provides it to the
 
 This guidance aims to cover all crucial aspects of designing AI services with Quarkus, ensuring robust and efficient interactions with LLMs.
 
+== Moderation
+
+By default, @RegisterAiService annotated interfaces don't moderate content. However, users can opt in to having the LLM moderate
+content by annotating the method with `@Moderate`.
+
+For moderation to work, the following criteria need to be met:
+
+* A CDI bean for `dev.langchain4j.model.moderation.ModerationModel` must be configured (the `quarkus-langchain4j-openai` and `quarkus-langchain4j-azure-openai` provide one out of the box)
+* The interface must be configured with `@RegisterAiService(moderationModelSupplier = RegisterAiService.BeanModerationModelSupplier.class)`
+
+=== Advanced usage
+An alternative to providing a CDI bean is to configure the interface with `@RegisterAiService(moderationModelSupplier = MyCustomSupplier.class)`
+and implement `MyCustomModerationSupplier` like so:
+
+[source,java]
+----
+import dev.langchain4j.model.moderation.ModerationModel;
+
+public class MyCustomModerationSupplier implements Supplier<ModerationModel> {
+
+    @Override
+    public ModerationModel get(){
+        // TODO: implement
+    }
+
+}
+----
+
 == Observability
 
 Observability is built into services created via `@RegisterAiService` and is provided in the following form: