Add Opensearch embedding store implementation

docs/modules/ROOT/examples/io/quarkiverse/langchain4j/samples/IngestorExampleWithOpenSearch.java

@@ -0,0 +1,41 @@
+package io.quarkiverse.langchain4j.samples;
+
+import static dev.langchain4j.data.document.splitter.DocumentSplitters.recursive;
+
+import java.util.List;
+
+import jakarta.enterprise.context.ApplicationScoped;
+import jakarta.inject.Inject;
+
+import dev.langchain4j.data.document.Document;
+import dev.langchain4j.model.embedding.EmbeddingModel;
+import dev.langchain4j.store.embedding.EmbeddingStoreIngestor;
+import io.quarkiverse.langchain4j.opensearch.OpenSearchEmbeddingStore;
+
+@ApplicationScoped
+public class IngestorExampleWithOpenSearch {
+
+    /**
+     * The embedding store (the database).
+     * The bean is provided by the quarkus-langchain4j-opensearch extension.
+     */
+    @Inject
+    OpenSearchEmbeddingStore store;
+
+    /**
+     * The embedding model (how is computed the vector of a document).
+     * The bean is provided by the LLM (like openai) extension.
+     */
+    @Inject
+    EmbeddingModel embeddingModel;
+
+    public void ingest(List<Document> documents) {
+        EmbeddingStoreIngestor ingestor = EmbeddingStoreIngestor.builder()
+                .embeddingStore(store)
+                .embeddingModel(embeddingModel)
+                .documentSplitter(recursive(500, 0))
+                .build();
+        // Warning - this can take a long time...
+        ingestor.ingest(documents);
+    }
+}

docs/modules/ROOT/pages/includes/quarkus-langchain4j-opensearch.adoc

@@ -0,0 +1,29 @@
+
+:summaryTableId: quarkus-langchain4j-opensearch
+[.configuration-legend]
+icon:lock[title=Fixed at build time] Configuration property fixed at build time - All other configuration properties are overridable at runtime
+[.configuration-reference.searchable, cols="80,.^10,.^10"]
+|===
+
+h|[[quarkus-langchain4j-opensearch_configuration]]link:#quarkus-langchain4j-opensearch_configuration[Configuration property]
+
+h|Type
+h|Default
+
+a| [[quarkus-langchain4j-opensearch_quarkus.langchain4j.opensearch.index]]`link:#quarkus-langchain4j-opensearch_quarkus.langchain4j.opensearch.index[quarkus.langchain4j.opensearch.index]`
+
+
+[.description]
+--
+Name of the index that will be used in OpenSearch when searching for related embeddings. If this index doesn't exist, it will be created.
+
+ifdef::add-copy-button-to-env-var[]
+Environment variable: env_var_with_copy_button:+++QUARKUS_LANGCHAIN4J_OPENSEARCH_INDEX+++[]
+endif::add-copy-button-to-env-var[]
+ifndef::add-copy-button-to-env-var[]
+Environment variable: `+++QUARKUS_LANGCHAIN4J_OPENSEARCH_INDEX+++`
+endif::add-copy-button-to-env-var[]
+--|string 
+|`default`
+
+|===

docs/modules/ROOT/pages/opensearch-store.adoc

@@ -0,0 +1,37 @@
+= OpenSearch Document Store for Retrieval Augmented Generation (RAG)
+
+include::./includes/attributes.adoc[]
+
+When implementing Retrieval Augmented Generation (RAG), a capable document store is necessary. This guide will explain how to leverage an _opensearch-store_ database as the document store.
+
+== Leveraging the OpenSearch Document Store
+
+To utilize the OpenSearch document store, you'll need to include the following dependency:
+
+[source,xml,subs=attributes+]
+----
+<dependency>
+    <groupId>io.quarkiverse.langchain4j</groupId>
+    <artifactId>quarkus-langchain4j-opensearch</artifactId>
+    <version>{project-version}</version>
+</dependency>
+----
+
+This extension relies on the OpenSearch Java Client, make sure you have one configured correctly.
+
+Upon installing the extension, you can utilize the opensearch store using the following code:
+
+[source,java]
+----
+include::{examples-dir}/io/quarkiverse/langchain4j/samples/IngestorExampleWithOpenSearch.java[]
+----
+
+== Configuration Settings
+
+Customize the behavior of the extension by exploring various configuration options:
+
+include::includes/quarkus-langchain4j-opensearch.adoc[leveloffset=+1,opts=optional]
+
+== Under the Hood
+
+Each ingested document is saved as a row in a Postgres table, containing the embedding column stored as a vector.

docs/pom.xml

@@ -41,6 +41,11 @@
             <artifactId>quarkus-langchain4j-pinecone</artifactId>
             <version>${project.version}</version>
         </dependency>
+        <dependency>
+            <groupId>io.quarkiverse.langchain4j</groupId>
+            <artifactId>quarkus-langchain4j-opensearch</artifactId>
+            <version>${project.version}</version>
+        </dependency>
 
         <!-- Make sure the doc is built after the other artifacts -->
         <dependency>
@@ -73,6 +78,11 @@
             <artifactId>quarkus-langchain4j-hugging-face-deployment</artifactId>
             <version>${project.version}</version>
         </dependency>
+        <dependency>
+            <groupId>io.quarkiverse.langchain4j</groupId>
+            <artifactId>quarkus-langchain4j-opensearch-deployment</artifactId>
+            <version>${project.version}</version>
+        </dependency>
     </dependencies>
 
     <build>
@@ -127,6 +137,7 @@
                                     <include>quarkus-langchain4j-chroma.adoc</include>
                                     <include>quarkus-langchain4j-pinecone.adoc</include>
                                     <include>quarkus-langchain4j-pgvector.adoc</include>
+                                    <include>quarkus-langchain4j-opensearch.adoc</include>
                                     <filtering>false</filtering>
                                 </resource>
                                 <resource>

opensearch/deployment/pom.xml

@@ -0,0 +1,79 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"
+         xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
+    <modelVersion>4.0.0</modelVersion>
+    <parent>
+        <groupId>io.quarkiverse.langchain4j</groupId>
+        <artifactId>quarkus-langchain4j-opensearch-parent</artifactId>
+        <version>999-SNAPSHOT</version>
+    </parent>
+    <artifactId>quarkus-langchain4j-opensearch-deployment</artifactId>
+    <name>Quarkus Langchain4j - Opensearch embedding store - Deployment</name>
+    <dependencies>
+        <dependency>
+            <groupId>io.quarkus</groupId>
+            <artifactId>quarkus-arc-deployment</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>io.quarkiverse.langchain4j</groupId>
+            <artifactId>quarkus-langchain4j-opensearch</artifactId>
+            <version>${project.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>io.quarkiverse.langchain4j</groupId>
+            <artifactId>quarkus-langchain4j-core-deployment</artifactId>
+            <version>${project.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>io.quarkiverse.opensearch</groupId>
+            <artifactId>quarkus-opensearch-java-client-deployment</artifactId>
+            <version>1.4.0</version>
+        </dependency>
+        <dependency>
+            <groupId>io.quarkus</groupId>
+            <artifactId>quarkus-junit5-internal</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.assertj</groupId>
+            <artifactId>assertj-core</artifactId>
+            <version>${assertj.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.wiremock</groupId>
+            <artifactId>wiremock-standalone</artifactId>
+            <version>${wiremock.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>dev.langchain4j</groupId>
+            <artifactId>langchain4j-embeddings-all-minilm-l6-v2-q</artifactId>
+            <version>${langchain4j-embeddings.version}</version>
+            <scope>test</scope>
+            <exclusions>
+                <exclusion>
+                    <groupId>dev.langchain4j</groupId>
+                    <artifactId>langchain4j-core</artifactId>
+                </exclusion>
+            </exclusions>
+        </dependency>
+    </dependencies>
+    <build>
+        <plugins>
+            <plugin>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <configuration>
+                    <annotationProcessorPaths>
+                        <path>
+                            <groupId>io.quarkus</groupId>
+                            <artifactId>quarkus-extension-processor</artifactId>
+                            <version>${quarkus.version}</version>
+                        </path>
+                    </annotationProcessorPaths>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
+</project>

opensearch/deployment/src/main/java/io/quarkiverse/langchain4j/opensearch/deployment/Langchain4jOpensearchProcessor.java

@@ -0,0 +1,60 @@
+package io.quarkiverse.langchain4j.opensearch.deployment;
+
+import jakarta.enterprise.context.ApplicationScoped;
+import jakarta.enterprise.inject.Default;
+
+import org.jboss.jandex.AnnotationInstance;
+import org.jboss.jandex.ClassType;
+import org.jboss.jandex.DotName;
+import org.jboss.jandex.ParameterizedType;
+import org.opensearch.client.opensearch.OpenSearchClient;
+
+import dev.langchain4j.data.segment.TextSegment;
+import dev.langchain4j.store.embedding.EmbeddingStore;
+import io.quarkiverse.langchain4j.deployment.EmbeddingStoreBuildItem;
+import io.quarkiverse.langchain4j.opensearch.OpenSearchEmbeddingStore;
+import io.quarkiverse.langchain4j.opensearch.runtime.OpenSearchEmbeddingStoreConfig;
+import io.quarkiverse.langchain4j.opensearch.runtime.OpenSearchEmbeddingStoreRecorder;
+import io.quarkus.arc.deployment.SyntheticBeanBuildItem;
+import io.quarkus.deployment.annotations.BuildProducer;
+import io.quarkus.deployment.annotations.BuildStep;
+import io.quarkus.deployment.annotations.ExecutionTime;
+import io.quarkus.deployment.annotations.Record;
+import io.quarkus.deployment.builditem.FeatureBuildItem;
+
+class Langchain4jOpensearchProcessor {
+
+    public static final DotName OPENSEARCH_EMBEDDING_STORE = DotName.createSimple(OpenSearchEmbeddingStore.class);
+
+    private static final String FEATURE = "langchain4j-opensearch";
+
+    @BuildStep
+    FeatureBuildItem feature() {
+        return new FeatureBuildItem(FEATURE);
+    }
+
+    @BuildStep
+    @Record(ExecutionTime.RUNTIME_INIT)
+    public void createBean(
+            BuildProducer<SyntheticBeanBuildItem> beanProducer,
+            OpenSearchEmbeddingStoreRecorder recorder,
+            OpenSearchEmbeddingStoreConfig config,
+            BuildProducer<EmbeddingStoreBuildItem> embeddingStoreProducer) {
+        AnnotationInstance openSearchClientQualifier;
+        openSearchClientQualifier = AnnotationInstance.builder(Default.class).build();
+
+        beanProducer.produce(SyntheticBeanBuildItem
+                .configure(OPENSEARCH_EMBEDDING_STORE)
+                .types(ClassType.create(EmbeddingStore.class),
+                        ParameterizedType.create(EmbeddingStore.class, ClassType.create(TextSegment.class)))
+                .setRuntimeInit()
+                .defaultBean()
+                .scope(ApplicationScoped.class)
+                .addInjectionPoint(ClassType.create(DotName.createSimple(OpenSearchClient.class)),
+                        openSearchClientQualifier)
+                .createWith(recorder.embeddingStoreFunction(config))
+                .done());
+        embeddingStoreProducer.produce(new EmbeddingStoreBuildItem());
+    }
+
+}