Moved remote index build client to a separate module

build.gradle

@@ -302,6 +302,7 @@ task release(type: Copy, group: 'build') {
 //****************************************************************************/
 dependencies {
     api "org.opensearch:opensearch:${opensearch_version}"
+    api project(":remote-index-build-client")
     compileOnly "org.opensearch.plugin:opensearch-scripting-painless-spi:${versions.opensearch}"
     api group: 'com.google.guava', name: 'failureaccess', version:'1.0.1'
     api group: 'com.google.guava', name: 'guava', version:'32.1.3-jre'
@@ -321,9 +322,6 @@ dependencies {
     api "net.java.dev.jna:jna-platform:5.13.0"
     // OpenSearch core is using slf4j 1.7.36. Therefore, we cannot change the version here.
     implementation 'org.slf4j:slf4j-api:1.7.36'
-    api "org.apache.httpcomponents.client5:httpclient5:${versions.httpclient5}"
-    api "org.apache.httpcomponents.core5:httpcore5:${versions.httpcore5}"
-    api "org.apache.httpcomponents.core5:httpcore5-h2:${versions.httpcore5}"
     zipArchive group: 'org.opensearch.plugin', name:'opensearch-security', version: "${opensearch_build}"
 }
 

remote-index-build-client/NOTICE.txt

@@ -0,0 +1,2 @@
+OpenSearch k-NN
+Copyright OpenSearch Contributors

remote-index-build-client/build.gradle

@@ -0,0 +1,61 @@
+/*
+ * Copyright OpenSearch Contributors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+plugins {
+    id 'java'
+    id 'java-library'
+    id 'jacoco'
+    id "io.freefair.lombok"
+    id 'com.diffplug.spotless' version '6.25.0'
+    id 'opensearch.build'
+}
+
+repositories {
+    mavenLocal()
+    maven { url "https://aws.oss.sonatype.org/content/repositories/snapshots" }
+    mavenCentral()
+    maven { url "https://plugins.gradle.org/m2/" }
+}
+
+compileJava {
+    options.compilerArgs.addAll(["-processor", 'lombok.launch.AnnotationProcessorHider$AnnotationProcessor'])
+}
+compileTestJava {
+    options.compilerArgs.addAll(["-processor", 'lombok.launch.AnnotationProcessorHider$AnnotationProcessor'])
+}
+
+dependencies {
+    compileOnly group: 'org.opensearch', name: 'opensearch', version: "${opensearch_version}"
+    api group: 'commons-lang', name: 'commons-lang', version: '2.6'
+    api "org.apache.httpcomponents.client5:httpclient5:${versions.httpclient5}"
+    api "org.apache.httpcomponents.core5:httpcore5:${versions.httpcore5}"
+    api "org.apache.httpcomponents.core5:httpcore5-h2:${versions.httpcore5}"
+    testImplementation "org.opensearch.test:framework:${opensearch_version}"
+}
+
+check.dependsOn spotlessCheck
+
+publishing {
+    publications {
+        pluginZip(MavenPublication) { publication ->
+            pom {
+                name = "opensearch-knn-remote-index-build-client"
+                description = 'Client for connecting to remote index build endpoint'
+                licenses {
+                    license {
+                        name = "The Apache License, Version 2.0"
+                        url = "http://www.apache.org/licenses/LICENSE-2.0.txt"
+                    }
+                }
+                developers {
+                    developer {
+                        name = "OpenSearch"
+                        url = "https://github.com/opensearch-project/k-NN/remote-index-build-client"
+                    }
+                }
+            }
+        }
+    }
+}

src/main/java/org/opensearch/knn/index/remote/RemoteIndexClient.java → remote-index-build-client/src/main/java/org/opensearch/remoteindexbuild/client/RemoteIndexClient.java

@@ -3,7 +3,11 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
-package org.opensearch.knn.index.remote;
+package org.opensearch.remoteindexbuild.client;
+
+import org.opensearch.remoteindexbuild.model.RemoteBuildRequest;
+import org.opensearch.remoteindexbuild.model.RemoteBuildResponse;
+import org.opensearch.remoteindexbuild.model.RemoteStatusResponse;
 
 import java.io.IOException;
 
@@ -12,6 +16,9 @@
  */
 public interface RemoteIndexClient {
 
+    String BUILD_ENDPOINT = "/_build";
+    String STATUS_ENDPOINT = "/_status";
+
     /**
      * Submit a build to the Remote Vector Build Service.
      * @return RemoteBuildResponse from the server

remote-index-build-client/src/main/java/org/opensearch/remoteindexbuild/client/RemoteIndexClientFactory.java

@@ -0,0 +1,14 @@
+/*
+ * Copyright OpenSearch Contributors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package org.opensearch.remoteindexbuild.client;
+
+public class RemoteIndexClientFactory {
+
+    // Default to HTTP client
+    public static RemoteIndexClient getRemoteIndexClient(final String endpoint) {
+        return new RemoteIndexHTTPClient(endpoint);
+    }
+}

src/main/java/org/opensearch/knn/index/remote/RemoteIndexHTTPClient.java → remote-index-build-client/src/main/java/org/opensearch/remoteindexbuild/client/RemoteIndexHTTPClient.java

@@ -3,10 +3,11 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
-package org.opensearch.knn.index.remote;
+package org.opensearch.remoteindexbuild.client;
 
 import lombok.extern.log4j.Log4j2;
 import org.apache.commons.lang.NotImplementedException;
+import org.apache.commons.lang.StringUtils;
 import org.apache.hc.client5.http.classic.methods.HttpPost;
 import org.apache.hc.client5.http.impl.classic.CloseableHttpClient;
 import org.apache.hc.client5.http.impl.classic.HttpClients;
@@ -16,18 +17,16 @@
 import org.apache.hc.core5.http.HttpStatus;
 import org.apache.hc.core5.http.io.entity.EntityUtils;
 import org.apache.hc.core5.http.io.entity.StringEntity;
-import org.opensearch.common.settings.Settings;
 import org.opensearch.common.xcontent.LoggingDeprecationHandler;
 import org.opensearch.common.xcontent.json.JsonXContent;
 import org.opensearch.core.common.settings.SecureString;
 import org.opensearch.core.xcontent.NamedXContentRegistry;
 import org.opensearch.core.xcontent.ToXContentObject;
 import org.opensearch.core.xcontent.XContentBuilder;
 import org.opensearch.core.xcontent.XContentParser;
-import org.opensearch.knn.index.KNNSettings;
-import org.opensearch.knn.index.codec.nativeindex.model.BuildIndexParams;
-import org.opensearch.knn.index.codec.nativeindex.remote.RemoteIndexBuildStrategy;
-import org.opensearch.knn.plugin.KNNPlugin;
+import org.opensearch.remoteindexbuild.model.RemoteBuildRequest;
+import org.opensearch.remoteindexbuild.model.RemoteBuildResponse;
+import org.opensearch.remoteindexbuild.model.RemoteStatusResponse;
 
 import java.io.Closeable;
 import java.io.IOException;
@@ -37,9 +36,6 @@
 import java.security.PrivilegedExceptionAction;
 
 import static org.apache.hc.core5.http.HttpStatus.SC_OK;
-import static org.opensearch.knn.index.KNNSettings.KNN_REMOTE_BUILD_CLIENT_PASSWORD_SETTING;
-import static org.opensearch.knn.index.KNNSettings.KNN_REMOTE_BUILD_CLIENT_USERNAME_SETTING;
-import static org.opensearch.knn.index.remote.KNNRemoteConstants.BUILD_ENDPOINT;
 
 /**
  * Class to handle all interactions with the remote vector build service.
@@ -71,11 +67,9 @@ protected static CloseableHttpClient getHttpClient() {
 
     /**
      * Creates the client, setting the endpoint per-instance so the same endpoint is used per-build operation
-     * (per call to {@link RemoteIndexBuildStrategy#buildAndWriteIndex(BuildIndexParams)})
      */
-    public RemoteIndexHTTPClient() {
-        String endpoint = KNNSettings.getRemoteBuildServiceEndpoint();
-        if (endpoint == null || endpoint.isEmpty()) {
+    public RemoteIndexHTTPClient(final String endpoint) {
+        if (StringUtils.isEmpty(endpoint)) {
             throw new IllegalArgumentException("No endpoint set for RemoteIndexClient");
         }
         this.endpoint = endpoint;
@@ -147,14 +141,11 @@ private String toJson(ToXContentObject object) throws IOException {
     }
 
     /**
-     * Set the global auth header to use the refreshed secure settings.
-     * Called by {@link KNNPlugin#reload(Settings)} when the nodes reload API is called.
-     * @param settings Settings to use to get the credentials
-     */
-    public static void reloadAuthHeader(Settings settings) {
-        SecureString username = KNN_REMOTE_BUILD_CLIENT_USERNAME_SETTING.get(settings);
-        SecureString password = KNN_REMOTE_BUILD_CLIENT_PASSWORD_SETTING.get(settings);
-
+    * Set the global auth header to use the refreshed secure settings.
+    * @param username username to use for authentication
+    * @param password password to use for authentication
+    */
+    public static void reloadAuthHeader(final SecureString username, final SecureString password) {
         if (password != null && !password.isEmpty()) {
             if (username == null || username.isEmpty()) {
                 throw new IllegalArgumentException("Username must be set if password is set");

src/main/java/org/opensearch/knn/index/remote/RemoteIndexHTTPClientRetryStrategy.java → remote-index-build-client/src/main/java/org/opensearch/remoteindexbuild/client/RemoteIndexHTTPClientRetryStrategy.java

@@ -3,7 +3,7 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
-package org.opensearch.knn.index.remote;
+package org.opensearch.remoteindexbuild.client;
 
 import org.apache.hc.client5.http.impl.DefaultHttpRequestRetryStrategy;
 import org.apache.hc.core5.http.ConnectionClosedException;

remote-index-build-client/src/main/java/org/opensearch/remoteindexbuild/constants/KNNRemoteConstants.java

@@ -0,0 +1,17 @@
+/*
+ * Copyright OpenSearch Contributors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package org.opensearch.remoteindexbuild.constants;
+
+// Public class to define the constants used by Remote Index Build in 2 or more classes.
+public class KNNRemoteConstants {
+    // Build request keys
+    public static final String ALGORITHM = "algorithm";
+    public static final String ALGORITHM_PARAMETERS = "algorithm_parameters";
+    public static final String METHOD_PARAMETER_SPACE_TYPE = "space_type";
+    public static final String METHOD_PARAMETER_EF_SEARCH = "ef_search";
+    public static final String METHOD_PARAMETER_EF_CONSTRUCTION = "ef_construction";
+    public static final String METHOD_PARAMETER_M = "m";
+}

remote-index-build-client/src/main/java/org/opensearch/remoteindexbuild/model/RemoteBuildRequest.java

@@ -0,0 +1,61 @@
+/*
+ * Copyright OpenSearch Contributors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package org.opensearch.remoteindexbuild.model;
+
+import lombok.Builder;
+import lombok.Value;
+import org.opensearch.core.xcontent.ToXContentObject;
+import org.opensearch.core.xcontent.XContentBuilder;
+
+import java.io.IOException;
+
+/**
+ * Request object for sending build requests to the remote build service, encapsulating all the required parameters
+ * in a generic XContent format.
+ */
+@Value
+@Builder
+public class RemoteBuildRequest implements ToXContentObject {
+    private static final String DOC_COUNT = "doc_count";
+    private static final String TENANT_ID = "tenant_id";
+    private static final String DOC_ID_PATH = "doc_id_path";
+    private static final String DIMENSION = "dimension";
+    private static final String VECTOR_DATA_TYPE_FIELD = "data_type";
+    private static final String KNN_ENGINE = "engine";
+
+    private static final String VECTOR_PATH = "vector_path";
+    private static final String CONTAINER_NAME = "container_name";
+    private static final String REPOSITORY_TYPE = "repository_type";
+    private static final String INDEX_PARAMETERS = "index_parameters";
+
+    String repositoryType;
+    String containerName;
+    String vectorPath;
+    String docIdPath;
+    String tenantId;
+    int dimension;
+    int docCount;
+    String vectorDataType;
+    String engine;
+    RemoteIndexParameters indexParameters;
+
+    @Override
+    public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
+        builder.startObject();
+        builder.field(REPOSITORY_TYPE, repositoryType);
+        builder.field(CONTAINER_NAME, containerName);
+        builder.field(VECTOR_PATH, vectorPath);
+        builder.field(DOC_ID_PATH, docIdPath);
+        builder.field(TENANT_ID, tenantId);
+        builder.field(DIMENSION, dimension);
+        builder.field(DOC_COUNT, docCount);
+        builder.field(VECTOR_DATA_TYPE_FIELD, vectorDataType);
+        builder.field(KNN_ENGINE, engine);
+        builder.field(INDEX_PARAMETERS, indexParameters);
+        builder.endObject();
+        return builder;
+    }
+}

src/main/java/org/opensearch/knn/index/remote/RemoteBuildResponse.java → remote-index-build-client/src/main/java/org/opensearch/remoteindexbuild/model/RemoteBuildResponse.java

@@ -3,7 +3,7 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
-package org.opensearch.knn.index.remote;
+package org.opensearch.remoteindexbuild.model;
 
 import lombok.Builder;
 import lombok.Value;

src/main/java/org/opensearch/knn/index/remote/RemoteFaissHNSWIndexParameters.java → remote-index-build-client/src/main/java/org/opensearch/remoteindexbuild/model/RemoteFaissHNSWIndexParameters.java

@@ -3,28 +3,27 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
-package org.opensearch.knn.index.remote;
+package org.opensearch.remoteindexbuild.model;
 
 import lombok.experimental.SuperBuilder;
 import org.opensearch.core.xcontent.XContentBuilder;
-import org.opensearch.knn.common.KNNConstants;
+import org.opensearch.remoteindexbuild.constants.KNNRemoteConstants;
 
 import java.io.IOException;
 
-import static org.opensearch.knn.index.remote.KNNRemoteConstants.ALGORITHM_PARAMETERS;
-
 @SuperBuilder
 public class RemoteFaissHNSWIndexParameters extends RemoteIndexParameters {
+
     int m;
     int efConstruction;
     int efSearch;
 
     @Override
     void addAlgorithmParameters(XContentBuilder builder) throws IOException {
-        builder.startObject(ALGORITHM_PARAMETERS);
-        builder.field(KNNConstants.METHOD_PARAMETER_M, m);
-        builder.field(KNNConstants.METHOD_PARAMETER_EF_CONSTRUCTION, efConstruction);
-        builder.field(KNNConstants.METHOD_PARAMETER_EF_SEARCH, efSearch);
+        builder.startObject(KNNRemoteConstants.ALGORITHM_PARAMETERS);
+        builder.field(KNNRemoteConstants.METHOD_PARAMETER_M, m);
+        builder.field(KNNRemoteConstants.METHOD_PARAMETER_EF_CONSTRUCTION, efConstruction);
+        builder.field(KNNRemoteConstants.METHOD_PARAMETER_EF_SEARCH, efSearch);
         builder.endObject();
     }
 }

src/main/java/org/opensearch/knn/index/remote/RemoteIndexParameters.java → remote-index-build-client/src/main/java/org/opensearch/remoteindexbuild/model/RemoteIndexParameters.java

@@ -3,27 +3,26 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
-package org.opensearch.knn.index.remote;
+package org.opensearch.remoteindexbuild.model;
 
 import lombok.experimental.SuperBuilder;
 import org.opensearch.core.xcontent.ToXContentObject;
 import org.opensearch.core.xcontent.XContentBuilder;
+import org.opensearch.remoteindexbuild.constants.KNNRemoteConstants;
 
 import java.io.IOException;
 
-import static org.opensearch.knn.common.KNNConstants.METHOD_PARAMETER_SPACE_TYPE;
-import static org.opensearch.knn.index.remote.KNNRemoteConstants.ALGORITHM;
-
 @SuperBuilder
 public abstract class RemoteIndexParameters implements ToXContentObject {
+
     String spaceType;
     String algorithm;
 
     @Override
     public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
         builder.startObject();
-        builder.field(METHOD_PARAMETER_SPACE_TYPE, spaceType);
-        builder.field(ALGORITHM, algorithm);
+        builder.field(KNNRemoteConstants.METHOD_PARAMETER_SPACE_TYPE, spaceType);
+        builder.field(KNNRemoteConstants.ALGORITHM, algorithm);
         addAlgorithmParameters(builder);
         builder.endObject();
         return builder;

src/main/java/org/opensearch/knn/index/remote/RemoteStatusResponse.java → remote-index-build-client/src/main/java/org/opensearch/remoteindexbuild/model/RemoteStatusResponse.java

@@ -3,7 +3,7 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
-package org.opensearch.knn.index.remote;
+package org.opensearch.remoteindexbuild.model;
 
 import lombok.AllArgsConstructor;
 import lombok.Getter;

remote-index-build-client/src/test/java/org/opensearch/remoteindexbuild/TestConstants.java

@@ -0,0 +1,19 @@
+/*
+ * Copyright OpenSearch Contributors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package org.opensearch.remoteindexbuild;
+
+public class TestConstants {
+    public static final String TEST_BUCKET = "test-bucket";
+    public static final String TEST_CLUSTER = "test-cluster";
+    public static final String MOCK_JOB_ID_RESPONSE = "{\"job_id\": \"job-1739930402\"}";
+    public static final String MOCK_JOB_ID = "job-1739930402";
+    public static final String MOCK_BLOB_NAME = "blob";
+    public static final String MOCK_ENDPOINT = "https://mock-build-service.com";
+    public static final String USERNAME = "username";
+    public static final String PASSWORD = "password";
+    public static final String L2_SPACE_TYPE = "l2";
+    public static final String HNSW_ALGORITHM = "hnsw";
+}