Use fixture to test repository-s3 plugin

This commit adds a new fixture that emulates a S3 service in order to
improve the existing integration tests. This is very similar to what has
 been made for Google Cloud Storage in elastic#28788, and such tests would have
 helped a lot to catch bugs like elastic#22534.

The AmazonS3Fixture is brittle and only implements the very necessary
stuff for the S3 repository to work, but at least it works and can be
adapted for specific tests needs.

plugins/repository-gcs/src/test/java/org/elasticsearch/repositories/gcs/GoogleCloudStorageFixture.java

@@ -58,7 +58,7 @@ public static void main(String[] args) throws Exception {
             throw new IllegalArgumentException("GoogleCloudStorageFixture <working directory> <bucket>");
         }
 
-        final InetSocketAddress socketAddress = new InetSocketAddress(InetAddress.getLoopbackAddress(), 43635);
+        final InetSocketAddress socketAddress = new InetSocketAddress(InetAddress.getLoopbackAddress(), 0);
         final HttpServer httpServer = MockHttpServer.createHttp(socketAddress, 0);
 
         try {

plugins/repository-gcs/src/test/resources/rest-api-spec/test/repository_gcs/10_basic.yml

@@ -28,7 +28,15 @@
             client: "integration_test"
 
   - match: { acknowledged: true }
-
+
+  # Get repository
+  - do:
+      snapshot.get_repository:
+        repository: repository
+
+  - match: {repository.settings.bucket : "bucket_test"}
+  - match: {repository.settings.client : "integration_test"}
+
   # Index documents
   - do:
       bulk:
@@ -180,7 +188,3 @@
   - do:
      snapshot.delete_repository:
        repository: repository
-
-
-
-

plugins/repository-s3/build.gradle

@@ -1,3 +1,5 @@
+import org.elasticsearch.gradle.test.AntFixture
+
 /*
  * Licensed to Elasticsearch under one or more contributor
  * license agreements. See the NOTICE file distributed with
@@ -64,9 +66,23 @@ test {
   exclude '**/*CredentialsTests.class'
 }
 
+/** A task to start the AmazonS3Fixture which emulates a S3 service **/
+task s3Fixture(type: AntFixture) {
+  dependsOn compileTestJava
+  env 'CLASSPATH', "${ -> project.sourceSets.test.runtimeClasspath.asPath }"
+  executable = new File(project.runtimeJavaHome, 'bin/java')
+  args 'org.elasticsearch.repositories.s3.AmazonS3Fixture', baseDir, 'bucket_test'
+}
+
 integTestCluster {
-  keystoreSetting 's3.client.default.access_key', 'myaccesskey'
-  keystoreSetting 's3.client.default.secret_key', 'mysecretkey'
+  dependsOn s3Fixture
+  setupCommand 'create-elasticsearch-keystore', 'bin/elasticsearch-keystore', 'create'
+
+  keystoreSetting 's3.client.integration_test.access_key', "s3_integration_test_access_key"
+  keystoreSetting 's3.client.integration_test.secret_key', "s3_integration_test_secret_key"
+
+  /* Use a closure on the string to delay evaluation until tests are executed */
+  setting 's3.client.integration_test.endpoint', "http://${ -> s3Fixture.addressAndPort }"
 }
 
 thirdPartyAudit.excludes = [

plugins/repository-s3/src/test/java/org/elasticsearch/repositories/s3/AmazonS3Fixture.java

@@ -0,0 +1,134 @@
+/*
+ * Licensed to Elasticsearch under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch 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 org.elasticsearch.repositories.s3;
+
+import com.sun.net.httpserver.HttpExchange;
+import com.sun.net.httpserver.HttpHandler;
+import com.sun.net.httpserver.HttpServer;
+import org.elasticsearch.common.SuppressForbidden;
+import org.elasticsearch.common.io.Streams;
+import org.elasticsearch.mocksocket.MockHttpServer;
+import org.elasticsearch.repositories.s3.AmazonS3TestServer.Response;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.lang.management.ManagementFactory;
+import java.net.Inet6Address;
+import java.net.InetAddress;
+import java.net.InetSocketAddress;
+import java.net.SocketAddress;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.nio.file.StandardCopyOption;
+import java.util.List;
+import java.util.Map;
+
+import static java.util.Collections.singleton;
+import static java.util.Collections.singletonList;
+
+/**
+ * {@link AmazonS3Fixture} is a fixture that emulates a S3 service.
+ * <p>
+ * It starts an asynchronous socket server that binds to a random local port. The server parses
+ * HTTP requests and uses a {@link AmazonS3TestServer} to handle them before returning
+ * them to the client as HTTP responses.
+ */
+public class AmazonS3Fixture {
+
+    @SuppressForbidden(reason = "PathUtils#get is fine - we don't have environment here")
+    public static void main(String[] args) throws Exception {
+        if (args == null || args.length != 2) {
+            throw new IllegalArgumentException("AmazonS3Fixture <working directory> <bucket>");
+        }
+
+        final InetSocketAddress socketAddress = new InetSocketAddress(InetAddress.getLoopbackAddress(), 0);
+        final HttpServer httpServer = MockHttpServer.createHttp(socketAddress, 0);
+
+        try {
+            final Path workingDirectory = Paths.get(args[0]);
+            /// Writes the PID of the current Java process in a `pid` file located in the working directory
+            writeFile(workingDirectory, "pid", ManagementFactory.getRuntimeMXBean().getName().split("@")[0]);
+
+            final String addressAndPort = addressToString(httpServer.getAddress());
+            // Writes the address and port of the http server in a `ports` file located in the working directory
+            writeFile(workingDirectory, "ports", addressAndPort);
+
+            // Emulates S3
+            final String storageUrl = "http://" + addressAndPort;
+            final AmazonS3TestServer storageTestServer = new AmazonS3TestServer(storageUrl);
+            storageTestServer.createBucket(args[1]);
+
+            httpServer.createContext("/", new ResponseHandler(storageTestServer));
+            httpServer.start();
+
+            // Wait to be killed
+            Thread.sleep(Long.MAX_VALUE);
+
+        } finally {
+            httpServer.stop(0);
+        }
+    }
+
+    private static void writeFile(final Path dir, final String fileName, final String content) throws IOException {
+        final Path tempPidFile = Files.createTempFile(dir, null, null);
+        Files.write(tempPidFile, singleton(content));
+        Files.move(tempPidFile, dir.resolve(fileName), StandardCopyOption.ATOMIC_MOVE);
+    }
+
+    private static String addressToString(final SocketAddress address) {
+        final InetSocketAddress inetSocketAddress = (InetSocketAddress) address;
+        if (inetSocketAddress.getAddress() instanceof Inet6Address) {
+            return "[" + inetSocketAddress.getHostString() + "]:" + inetSocketAddress.getPort();
+        } else {
+            return inetSocketAddress.getHostString() + ":" + inetSocketAddress.getPort();
+        }
+    }
+
+    @SuppressForbidden(reason = "Use a http server")
+    static class ResponseHandler implements HttpHandler {
+
+        private final AmazonS3TestServer storageServer;
+
+        private ResponseHandler(final AmazonS3TestServer storageServer) {
+            this.storageServer = storageServer;
+        }
+
+        @Override
+        public void handle(HttpExchange exchange) throws IOException {
+            String method = exchange.getRequestMethod();
+            String path = storageServer.getEndpoint() + exchange.getRequestURI().getRawPath();
+            String query = exchange.getRequestURI().getRawQuery();
+            Map<String, List<String>> headers = exchange.getRequestHeaders();
+            ByteArrayOutputStream out = new ByteArrayOutputStream();
+            Streams.copy(exchange.getRequestBody(), out);
+
+            final Response storageResponse = storageServer.handle(method, path, query, headers, out.toByteArray());
+
+            Map<String, List<String>> responseHeaders = exchange.getResponseHeaders();
+            responseHeaders.put("Content-Type", singletonList(storageResponse.contentType));
+            storageResponse.headers.forEach((k, v) -> responseHeaders.put(k, singletonList(v)));
+            exchange.sendResponseHeaders(storageResponse.status.getStatus(), storageResponse.body.length);
+            if (storageResponse.body.length > 0) {
+                exchange.getResponseBody().write(storageResponse.body);
+            }
+            exchange.close();
+        }
+    }
+}