[Backport 9.2] Move Rest5 client to a separate subproject

.ci/Dockerfile

@@ -44,10 +44,13 @@ RUN ./gradlew
 
 COPY --chown=$BUILDER_UID:$BUILDER_GID LICENSE.txt NOTICE.txt ./
 
+
+
 # Prefetch and cache dependencies
 COPY --chown=$BUILDER_UID:$BUILDER_GID build.gradle.kts settings.gradle.kts ./
 COPY --chown=$BUILDER_UID:$BUILDER_GID buildSrc ./buildSrc/
 COPY --chown=$BUILDER_UID:$BUILDER_GID config ./config/
+COPY --chown=$BUILDER_UID:$BUILDER_GID rest5-client ./rest5-client/
 COPY --chown=$BUILDER_UID:$BUILDER_GID java-client/build.gradle.kts ./java-client/
 RUN ./gradlew resolveDependencies
 

java-client/build.gradle.kts

@@ -179,6 +179,8 @@ dependencies {
     val jacksonVersion = "2.18.3"
     val openTelemetryVersion = "1.32.0"
 
+    api(project(":rest5-client"))
+
     // Apache 2.0
     // https://www.elastic.co/guide/en/elasticsearch/client/java-rest/current/java-rest-low.html
     compileOnly("org.elasticsearch.client", "elasticsearch-rest-client", elasticsearchVersion)

java-client/src/test/java/co/elastic/clients/transport/rest5_client/low_level/SafeResponseConsumerTest.java → java-client/src/test/java/co/elastic/clients/transport/rest5_client/SafeResponseConsumerTest.java

@@ -17,21 +17,30 @@
  * under the License.
  */
 
-package co.elastic.clients.transport.rest5_client.low_level;
-
-import co.elastic.clients.transport.rest5_client.SafeResponseConsumer;
+package co.elastic.clients.transport.rest5_client;
+
+import co.elastic.clients.transport.rest5_client.low_level.BufferedByteConsumer;
+import co.elastic.clients.transport.rest5_client.low_level.HttpAsyncResponseConsumerFactory;
+import co.elastic.clients.transport.rest5_client.low_level.Request;
+import co.elastic.clients.transport.rest5_client.low_level.RequestOptions;
+import co.elastic.clients.transport.rest5_client.low_level.Response;
+import co.elastic.clients.transport.rest5_client.low_level.Rest5Client;
 import com.sun.net.httpserver.HttpServer;
+import org.apache.hc.core5.http.ClassicHttpResponse;
 import org.apache.hc.core5.http.ContentType;
+import org.apache.hc.core5.http.HttpException;
 import org.apache.hc.core5.http.HttpHost;
 import org.apache.hc.core5.http.HttpResponse;
 import org.apache.hc.core5.http.io.entity.ByteArrayEntity;
 import org.apache.hc.core5.http.message.BasicClassicHttpResponse;
-import org.apache.hc.core5.http.protocol.HttpContext;
+import org.apache.hc.core5.http.nio.AsyncResponseConsumer;
+import org.apache.hc.core5.http.nio.support.AbstractAsyncResponseConsumer;
 import org.junit.jupiter.api.AfterAll;
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.BeforeAll;
 import org.junit.jupiter.api.Test;
 
+import java.io.IOException;
 import java.net.InetAddress;
 import java.net.InetSocketAddress;
 import java.nio.charset.StandardCharsets;
@@ -42,20 +51,36 @@ public class SafeResponseConsumerTest {
     static HttpHost ESHost;
 
     // A consumer factory that throws an Error, to simulate the effect of an OOME
-    static HttpAsyncResponseConsumerFactory FailingConsumerFactory =
-        () -> new BasicAsyncResponseConsumer(new BufferedByteConsumer(100 * 1024 * 1024)) {
-            @Override
-            public void informationResponse(HttpResponse response, HttpContext context) {
-                super.informationResponse(response, context);
-            }
+    static HttpAsyncResponseConsumerFactory FailingConsumerFactory = new FailingAsyncResponseConsumerFactory();
 
-            @Override
-            protected BasicClassicHttpResponse buildResult(HttpResponse response, ByteArrayEntity entity,
-                                                           ContentType contentType) {
-                super.buildResult(response, entity, contentType);
-                throw new Error("Error in buildResult");
-            }
-        };
+    static class FailingAsyncResponseConsumerFactory implements HttpAsyncResponseConsumerFactory {
+        @Override
+        public AsyncResponseConsumer<ClassicHttpResponse> createHttpAsyncResponseConsumer() {
+            return new FailingAsyncResponseConsumer();
+        }
+    }
+
+    static class FailingAsyncResponseConsumer extends AbstractAsyncResponseConsumer<ClassicHttpResponse,
+        ByteArrayEntity> {
+
+        FailingAsyncResponseConsumer() {
+            super(new BufferedByteConsumer(100));
+        }
+
+        @Override
+        public void informationResponse(HttpResponse response, org.apache.hc.core5.http.protocol.HttpContext context)
+            throws HttpException, IOException {
+            throw new Error("Error in informationResponse");
+        }
+
+        @Override
+        protected BasicClassicHttpResponse buildResult(
+            HttpResponse response, ByteArrayEntity entity,
+            ContentType contentType
+        ) {
+            throw new Error("Error in buildResult");
+        }
+    }
 
     @BeforeAll
     public static void setup() throws Exception {

rest5-client/README.md

@@ -0,0 +1,7 @@
+# rest5-client
+
+The Elasticsearch Java client historically used a "Low Level Rest Client" (LLRC) based on Apache http client version 4 to handle http communications and distribution of requests among the nodes of a cluster.
+
+This directory is a port of this client to Apache http client version 5 that is mostly a drop-in replacement, except for the initialization phase.
+
+It is provided as an independent library as a convenience to users who have an existing code based on LLRC and would like to migrate to the more modern Apache http 5 library.

rest5-client/build.gradle.kts

@@ -0,0 +1,246 @@
+/*
+ * 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.
+ */
+
+import com.github.jk1.license.ProjectData
+import com.github.jk1.license.render.LicenseDataCollector
+import com.github.jk1.license.render.ReportRenderer
+import java.io.FileWriter
+
+plugins {
+    java
+    `java-library`
+    `maven-publish`
+    publishing
+    checkstyle
+    signing
+    id("com.github.jk1.dependency-license-report") version "2.2"
+}
+
+checkstyle {
+    toolVersion = "10.16.0"
+}
+
+java {
+    targetCompatibility = JavaVersion.VERSION_17
+    sourceCompatibility = JavaVersion.VERSION_17
+
+    withJavadocJar()
+    withSourcesJar()
+}
+
+tasks.compileJava {
+    options.release.set(17)
+}
+
+tasks.withType<Test> {
+    useJUnitPlatform()
+}
+
+tasks.withType<Jar> {
+    doFirst {
+        if (rootProject.extra.has("gitHashFull")) {
+            val jar = this as Jar
+            jar.manifest.attributes["X-Git-Revision"] = rootProject.extra["gitHashFull"]
+            jar.manifest.attributes["X-Git-Commit-Time"] = rootProject.extra["gitCommitTime"]
+        } else {
+            throw GradleException("No git information available")
+        }
+    }
+
+    manifest {
+        attributes["Implementation-Title"] = "Elasticsearch Java client"
+        attributes["Implementation-Vendor"] = "Elastic"
+        attributes["Implementation-URL"] = "https://github.com/elastic/elasticsearch-java/"
+        attributes["Build-Date"] = rootProject.extra["buildTime"]
+    }
+
+    metaInf {
+        from("../LICENSE.txt")
+        from("../NOTICE.txt")
+    }
+}
+
+tasks.withType<Javadoc> {
+    val opt = options as StandardJavadocDocletOptions
+    // Gradle calls javadoc with a list of file and not a path. This prevents doc-files from being copied.
+    opt.addStringOption("sourcepath", project.projectDir.path + "/src/main/java")
+    opt.docFilesSubDirs(true)
+    opt.addBooleanOption("Xdoclint:-missing", true)
+}
+
+publishing {
+    repositories {
+        maven {
+            // See https://docs.github.com/en/packages/working-with-a-github-packages-registry/working-with-the-gradle-registry
+            name = "ESJavaGithubPackages"
+            url = uri("https://maven.pkg.github.com/elastic/elasticsearch-java")
+            credentials(PasswordCredentials::class)
+        }
+
+        maven {
+            name = "Build"
+            url = uri("${rootProject.layout.buildDirectory.get().asFile}/repository")
+        }
+    }
+
+    publications {
+        create<MavenPublication>("maven") {
+            from(components["java"])
+            pom {
+                name.set("Elasticsearch Rest5 Client")
+                artifactId = "elasticsearch-rest5-client"
+                description.set("Low level client based on http5")
+                url.set("https://github.com/elastic/elasticsearch-java/")
+                licenses {
+                    license {
+                        name.set("The Apache Software License, Version 2.0")
+                        url.set("https://www.apache.org/licenses/LICENSE-2.0.txt")
+                    }
+                }
+                developers {
+                    developer {
+                        name.set("Elastic")
+                        url.set("https://www.elastic.co")
+                        inceptionYear.set("2020")
+                    }
+                }
+                scm {
+                    connection.set("scm:git:https://github.com/elastic/elasticsearch-java.git")
+                    developerConnection.set("scm:git:ssh://[email protected]:elastic/elasticsearch-java.git")
+                    url.set("https://github.com/elastic/elasticsearch-java/")
+                }
+            }
+        }
+    }
+}
+
+
+signing {
+    // Only sign if a key has been configured in gradle.properties
+    isRequired = providers.gradleProperty("signing.keyId").isPresent
+    sign(publishing.publications["maven"])
+}
+
+dependencies {
+    val jacksonVersion = "2.18.3"
+
+    // Apache 2.0
+    // https://hc.apache.org/httpcomponents-client-ga/
+    api("org.apache.httpcomponents.client5","httpclient5","5.4.4")
+
+    // Apache 2.0
+    // http://commons.apache.org/logging/
+    api("commons-logging:commons-logging:1.3.5")
+
+    testImplementation("org.apache.commons:commons-lang3:3.14.0")
+    testImplementation("junit:junit:4.13.2")
+
+    // Apache 2.0
+    // https://github.com/FasterXML/jackson
+    implementation("com.fasterxml.jackson.core", "jackson-core", jacksonVersion)
+    implementation("com.fasterxml.jackson.core", "jackson-databind", jacksonVersion)
+
+//    // Apache-2.0
+//    testImplementation("commons-io:commons-io:2.17.0")
+
+    // EPL-2.0
+    // https://junit.org/junit5/
+    testImplementation("org.junit.jupiter:junit-jupiter-api:5.8.2")
+    testRuntimeOnly("org.junit.jupiter:junit-jupiter-engine:5.8.2")
+
+    // Apache-2.0
+    // https://github.com/awaitility/awaitility
+    testImplementation("org.awaitility", "awaitility", "4.2.0")
+
+    // MIT
+    // https://github.com/mockito/mockito
+    testImplementation("org.mockito","mockito-core","5.12.0")
+
+    // Apache-2.0
+    // https://github.com/elastic/mocksocket
+    testImplementation("org.elasticsearch","mocksocket","1.2")
+
+}
+
+
+licenseReport {
+    renderers = arrayOf(SpdxReporter(File(rootProject.layout.buildDirectory.get().asFile, "release/dependencies.csv")))
+    excludeGroups = arrayOf("org.elasticsearch.client")
+}
+
+class SpdxReporter(val dest: File) : ReportRenderer {
+    // License names to their SPDX identifier
+    val spdxIds = mapOf(
+        "The Apache License, Version 2.0" to "Apache-2.0",
+        "Apache License, Version 2.0" to "Apache-2.0",
+        "The Apache Software License, Version 2.0" to "Apache-2.0",
+        "Apache-2.0" to "Apache-2.0",
+        "MIT License" to "MIT",
+        "BSD Zero Clause License" to "0BSD",
+        "Eclipse Public License 2.0" to "EPL-2.0",
+        "Eclipse Public License v. 2.0" to "EPL-2.0",
+        "Eclipse Public License - v 2.0" to "EPL-2.0",
+        "GNU General Public License, version 2 with the GNU Classpath Exception" to "GPL-2.0 WITH Classpath-exception-2.0",
+        "COMMON DEVELOPMENT AND DISTRIBUTION LICENSE (CDDL) Version 1.0" to "CDDL-1.0"
+    )
+
+    private fun quote(str: String): String {
+        return if (str.contains(',') || str.contains("\"")) {
+            "\"" + str.replace("\"", "\"\"") + "\""
+        } else {
+            str
+        }
+    }
+
+    override fun render(data: ProjectData?) {
+        dest.parentFile.mkdirs()
+        FileWriter(dest).use { out ->
+            out.append("name,url,version,revision,license\n")
+            data?.allDependencies?.forEach { dep ->
+
+                val depVersion = dep.version
+                val depName = dep.group + ":" + dep.name
+
+                val info = LicenseDataCollector.multiModuleLicenseInfo(dep)
+                val depUrl = when(dep.group) {
+                    "org.apache.httpcomponents.client5" -> "https://hc.apache.org/"
+                    "org.apache.httpcomponents.core5" -> "https://hc.apache.org/"
+                    "com.fasterxml.jackson" -> "https://github.com/FasterXML/jackson"
+                    else -> if (info.moduleUrls.isEmpty()) {
+                        throw RuntimeException("No URL found for module '$depName'")
+                    } else {
+                        info.moduleUrls.first()
+                    }
+                }
+
+                val licenseIds = info.licenses.mapNotNull { license ->
+                    license.name?.let {
+                        checkNotNull(spdxIds[it]) { "No SPDX identifier for $license" }
+                    }
+                }.toSet()
+
+                // Combine multiple licenses.
+                // See https://spdx.github.io/spdx-spec/appendix-IV-SPDX-license-expressions/#composite-license-expressions
+                val licenseId = licenseIds.joinToString(" OR ")
+
+                out.append("${quote(depName)},${quote(depUrl)},${quote(depVersion)},,${quote(licenseId)}\n")
+            }
+        }
+    }
+}

java-client/src/main/java/co/elastic/clients/transport/rest5_client/low_level/BufferedByteConsumer.java → rest5-client/src/main/java/co/elastic/clients/transport/rest5_client/low_level/BufferedByteConsumer.java

@@ -28,13 +28,13 @@
 
 import static co.elastic.clients.transport.rest5_client.low_level.Constants.DEFAULT_BUFFER_INITIAL_CAPACITY;
 
-class BufferedByteConsumer extends AbstractBinAsyncEntityConsumer<ByteArrayEntity> {
+public class BufferedByteConsumer extends AbstractBinAsyncEntityConsumer<ByteArrayEntity> {
 
     private volatile ByteArrayBuffer buffer;
     private final int limit;
     private ContentType contentType;
 
-    BufferedByteConsumer(int bufferLimit) {
+    public BufferedByteConsumer(int bufferLimit) {
         super();
         if (bufferLimit <= 0) {
             throw new IllegalArgumentException("Buffer limit must be greater than 0");

java-client/src/test/java/co/elastic/clients/transport/rest5_client/low_level/HostsTrackingFailureListener.java → rest5-client/src/test/java/co/elastic/clients/transport/rest5_client/low_level/HostsTrackingFailureListener.java

@@ -20,7 +20,6 @@
 package co.elastic.clients.transport.rest5_client.low_level;
 
 import org.apache.hc.core5.http.HttpHost;
-import org.elasticsearch.client.RestClient;
 
 import java.util.HashSet;
 import java.util.List;
@@ -31,7 +30,7 @@
 import static org.junit.Assert.assertThat;
 
 /**
- * {@link RestClient.FailureListener} impl that allows to track when it gets called for which host.
+ * {@link Rest5Client.FailureListener} impl that allows to track when it gets called for which host.
  */
 class HostsTrackingFailureListener extends Rest5Client.FailureListener {
     private volatile Set<HttpHost> httpHosts = new HashSet<>();