Add base64 string vector utility and test (#1132)

* add base64 string vector utility and test

* license header

Author: l-trotta

java-client/src/main/java/co/elastic/clients/elasticsearch/_helpers/vector/AbstractBase64VectorDocument.java

@@ -0,0 +1,50 @@
+/*
+ * Licensed to Elasticsearch B.V. under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch B.V. licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package co.elastic.clients.elasticsearch._helpers.vector;
+
+import java.nio.ByteBuffer;
+import java.util.Base64;
+
+/**
+ * Utility class that can be extended to be used as vector type document,
+ * which will translate float array vectors in a base64 format accepted by Elasticsearch version 9.3+,
+ * with increased ingestion performance
+ * <p>
+ * Check {@link Base64VectorTest} for example usage
+ */
+public class AbstractBase64VectorDocument {
+    private String vector;
+
+    public void setVector(float[] vec) {
+        ByteBuffer buff = ByteBuffer.allocate(Float.BYTES * vec.length);
+        for (int i = 0; i < vec.length; i++) {
+            buff.putFloat(vec[i]);
+        }
+        this.vector = Base64.getEncoder().encodeToString(buff.array());
+    }
+
+    public void setVector(String vec) {
+        this.vector = vec;
+    }
+
+    public String getVector() {
+        return vector;
+    }
+}

java-client/src/test/java/co/elastic/clients/elasticsearch/_helpers/vector/Base64VectorTest.java

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+/*
+ * Licensed to Elasticsearch B.V. under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch B.V. licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package co.elastic.clients.elasticsearch._helpers.vector;
+
+import co.elastic.clients.elasticsearch.ElasticsearchClient;
+import co.elastic.clients.elasticsearch.ElasticsearchTestClient;
+import co.elastic.clients.elasticsearch.ElasticsearchTestServer;
+import co.elastic.clients.elasticsearch.core.SearchResponse;
+import co.elastic.clients.json.jackson.JacksonJsonpMapper;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.StringReader;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+public class Base64VectorTest {
+
+    static ElasticsearchClient elasticsearchClient;
+    private static final String INDEX = "vec-64-ingest-test";
+
+    @BeforeAll
+    public static void setup() {
+        var server = ElasticsearchTestServer.global();
+        elasticsearchClient = ElasticsearchTestClient.createClient(server.url(), new JacksonJsonpMapper(),
+            server.sslContext(), null);
+    }
+
+    @Test
+    public void oneBase64VectorIngestTest() throws IOException {
+        // Reading one example vector from file
+        InputStream input = this.getClass()
+            .getResourceAsStream("just-1-vector.json");
+
+        ObjectMapper mapper = new ObjectMapper();
+        JsonVector vectorDoc = mapper.readerFor(JsonVector.class).readValue(input);
+
+        // Converting vector from array of floats to base64 using utility class
+        CustomVectorDoc customVectorDoc = new CustomVectorDoc(vectorDoc.docid(),vectorDoc.title(), vectorDoc.text(), vectorDoc.emb());
+
+        // Or, alternatively, explicitly use the setVector() method provided by AbstractBase64VectorDocument
+        // CustomVectorDoc customVectorDocAlt = new CustomVectorDoc(vectorDoc.docid(),vectorDoc.title(), vectorDoc.text());
+        // customVectorDocAlt.setVector(vectorDoc.emb());
+
+        // Creating index explicitly indicating that the "vector" field will be of type dense vector
+        // While usually elasticsearch is able to autodetect the field type when automatically creating an index,
+        // in this specific case when using base64 string to represent vectors, it's necessary to manually map the
+        // vector field as dense vector.
+        if (elasticsearchClient.indices().exists(e -> e.index(INDEX)).value()) {
+            elasticsearchClient.indices().delete(d -> d.index(INDEX));
+            elasticsearchClient.indices().create(c -> c.index(INDEX)
+                .withJson(new StringReader("{\n" +
+                                           "    \"mappings\": {\n" +
+                                           "      \"properties\": {\n" +
+                                           "        \"text\": {\n" +
+                                           "          \"type\": \"text\",\n" +
+                                           "          \"fields\": {\n" +
+                                           "            \"keyword\": {\n" +
+                                           "              \"type\": \"keyword\",\n" +
+                                           "              \"ignore_above\": 256\n" +
+                                           "            }\n" +
+                                           "          }\n" +
+                                           "        },\n" +
+                                           "        \"vector\": {\n" +
+                                           "          \"type\": \"dense_vector\",\n" +
+                                           "          \"dims\": 1536,\n" +
+                                           "          \"index\": true,\n" +
+                                           "          \"similarity\": \"cosine\",\n" +
+                                           "          \"index_options\": {\n" +
+                                           "            \"type\": \"flat\"\n" +
+                                           "          }\n" +
+                                           "        }\n" +
+                                           "      }\n" +
+                                           "    }\n" +
+                                           "}")));
+            elasticsearchClient.indices().refresh();
+        }
+
+        // Indexing the vector
+        elasticsearchClient.index(i -> i
+            .index(INDEX)
+            .document(customVectorDoc)
+        );
+
+        // Refreshing to make sure we can query the vector
+        elasticsearchClient.indices().refresh();
+
+        // Asserting exactly 1 vector has been ingested
+        assertEquals(1L, elasticsearchClient.indices().stats().all().total().docs().count());
+
+        // Asserting vector can be deserialized
+        SearchResponse<CustomVectorDoc> resp = elasticsearchClient.search(s -> s.index(INDEX),
+            CustomVectorDoc.class);
+
+        assertEquals(customVectorDoc.getVector(),resp.hits().hits().get(0).source().getVector());
+
+        // Cleanup
+        elasticsearchClient.indices().delete(d -> d.index(INDEX));
+    }
+}

java-client/src/test/java/co/elastic/clients/elasticsearch/_helpers/vector/CustomVectorDoc.java

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+/*
+ * Licensed to Elasticsearch B.V. under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch B.V. licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package co.elastic.clients.elasticsearch._helpers.vector;
+
+public final class CustomVectorDoc extends AbstractBase64VectorDocument {
+    private String docid;
+    private String title;
+    private String text;
+
+    public CustomVectorDoc() {
+    }
+
+    public CustomVectorDoc(String docid, String title, String text, float[] vector) {
+        this.docid = docid;
+        this.title = title;
+        this.text = text;
+        this.setVector(vector);
+    }
+
+    public CustomVectorDoc(String docid, String title, String text) {
+        this.docid = docid;
+        this.title = title;
+        this.text = text;
+    }
+
+    public String getDocid() {
+        return docid;
+    }
+
+    public String getTitle() {
+        return title;
+    }
+
+    public String getText() {
+        return text;
+    }
+
+    public void setDocid(String docid) {
+        this.docid = docid;
+    }
+
+    public void setTitle(String title) {
+        this.title = title;
+    }
+
+    public void setText(String text) {
+        this.text = text;
+    }
+}

java-client/src/test/java/co/elastic/clients/elasticsearch/_helpers/vector/JsonVector.java

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+/*
+ * Licensed to Elasticsearch B.V. under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch B.V. licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package co.elastic.clients.elasticsearch._helpers.vector;
+
+public record JsonVector(String docid, String title, String text, float[] emb) {
+}