add spring boot example

Author: vga91

neo4j-example/pom.xml

@@ -7,20 +7,40 @@
     <groupId>dev.langchain4j</groupId>
     <artifactId>neo4j-example</artifactId>
     <version>1.0.0-beta4</version>
-
+    <parent>
+        <groupId>org.springframework.boot</groupId>
+        <artifactId>spring-boot-starter-parent</artifactId>
+        <version>3.2.5</version>
+        <relativePath/>
+    </parent>
+    
     <properties>
         <maven.compiler.source>17</maven.compiler.source>
         <maven.compiler.target>17</maven.compiler.target>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+        <java.version>17</java.version>
     </properties>
 
     <dependencies>
-
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-web</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>dev.langchain4j</groupId>
+            <artifactId>langchain4j-spring-boot-starter</artifactId>
+            <version>${project.version}</version>
+        </dependency>
         <dependency>
             <groupId>dev.langchain4j</groupId>
             <artifactId>langchain4j-community-neo4j</artifactId>
             <version>${project.version}</version>
         </dependency>
+        <dependency>
+            <groupId>dev.langchain4j</groupId>
+            <artifactId>langchain4j-community-neo4j-spring-boot-starter</artifactId>
+            <version>${project.version}</version>
+        </dependency>
 
         <dependency>
             <groupId>dev.langchain4j</groupId>

neo4j-example/src/main/java/com/example/demo/EmbeddingController.java

@@ -0,0 +1,42 @@
+package com.example.demo;
+
+import dev.langchain4j.data.embedding.Embedding;
+import dev.langchain4j.data.segment.TextSegment;
+import dev.langchain4j.model.embedding.EmbeddingModel;
+import dev.langchain4j.store.embedding.EmbeddingStore;
+import dev.langchain4j.store.embedding.EmbeddingSearchRequest;
+import org.springframework.web.bind.annotation.*;
+
+import java.util.List;
+
+@RestController
+@RequestMapping("/api/embeddings")
+public class EmbeddingController {
+
+    private final EmbeddingStore<TextSegment> store;
+    private final EmbeddingModel model;
+
+    public EmbeddingController(EmbeddingStore<TextSegment> store, EmbeddingModel model) {
+        this.store = store;
+        this.model = model;
+    }
+
+    @PostMapping("/add")
+    public String add(@RequestBody String text) {
+        TextSegment segment = TextSegment.from(text);
+        Embedding embedding = model.embed(text).content();
+        return store.add(embedding, segment);
+    }
+
+    @PostMapping("/search")
+    public List<String> search(@RequestBody String query) {
+        Embedding queryEmbedding = model.embed(query).content();
+        EmbeddingSearchRequest request = EmbeddingSearchRequest.builder()
+                .queryEmbedding(queryEmbedding)
+                .maxResults(5)
+                .build();
+        return store.search(request).matches()
+                .stream()
+                .map(i -> i.embedded().text()).toList();
+    }
+}

neo4j-example/src/main/java/com/example/demo/SpringBootExample.java

@@ -0,0 +1,32 @@
+package com.example.demo;
+
+import dev.langchain4j.model.embedding.onnx.allminilml6v2.AllMiniLmL6V2EmbeddingModel;
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.context.annotation.Bean;
+
+/**
+ * NOTE:
+ * This example assumes we have a Neo4j instance with Bolt URI bolt://localhost:7687, username 'neo4j' and password 'pass1234'
+ * as specified in the application.properties.
+ * If needed, change the properties values to address a running instance.
+ * 
+ * To add an embedding
+ * curl -X POST localhost:8083/api/embeddings/add -H "Content-Type: text/plain" -d "embeddingTest"
+ * 
+ * To search embeddings
+ * curl -X POST localhost:8083/api/embeddings/search -H "Content-Type: text/plain" -d "querySearchTest"
+ */
+@SpringBootApplication
+public class SpringBootExample {
+
+    public static void main(String[] args) {
+        SpringApplication.run(SpringBootExample.class, args);
+    }
+
+    @Bean
+    public AllMiniLmL6V2EmbeddingModel embeddingModel() {
+        return new AllMiniLmL6V2EmbeddingModel();
+    }
+    
+}

neo4j-example/src/main/resources/application.properties

@@ -0,0 +1,8 @@
+spring.application.name=LangChain4j Spring Boot Example
+server.port=8083
+
+langchain4j.community.neo4j.auth.uri=bolt://localhost:7687
+langchain4j.community.neo4j.auth.user=neo4j
+langchain4j.community.neo4j.auth.password=pass1234
+langchain4j.community.neo4j.label=CustomLabel
+langchain4j.community.neo4j.dimension=384