nastra commented on code in PR #14161: URL: https://github.com/apache/iceberg/pull/14161#discussion_r2523634298
########## aws/src/main/java/org/apache/iceberg/aws/ManagedHttpClientRegistry.java: ########## @@ -0,0 +1,201 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF 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.apache.iceberg.aws; + +import java.util.concurrent.ConcurrentMap; +import java.util.concurrent.atomic.AtomicInteger; +import java.util.function.Supplier; +import org.apache.iceberg.relocated.com.google.common.annotations.VisibleForTesting; +import org.apache.iceberg.relocated.com.google.common.collect.Maps; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; +import software.amazon.awssdk.http.SdkHttpClient; + +/** + * A registry that manages the lifecycle of shared HTTP clients for AWS SDK v2 using reference + * counting. + */ +public final class ManagedHttpClientRegistry { + private static final Logger LOG = LoggerFactory.getLogger(ManagedHttpClientRegistry.class); + + private final ConcurrentMap<String, ManagedHttpClient> clientMap; + + private static volatile ManagedHttpClientRegistry instance; + + public static ManagedHttpClientRegistry getInstance() { + if (instance == null) { + synchronized (ManagedHttpClientRegistry.class) { + if (instance == null) { + instance = new ManagedHttpClientRegistry(); + } + } + } + return instance; + } + + private ManagedHttpClientRegistry() { + this.clientMap = Maps.newConcurrentMap(); + } + + /** + * Get or create a managed HTTP client for the given configuration. Each call increments the + * reference count for the client and returns a ref-counted wrapper. + * + * @param clientKey unique key identifying the client configuration + * @param clientFactory factory to create the HTTP client if not cached + * @return a ref-counted HTTP client wrapper + */ + public SdkHttpClient getOrCreateClient(String clientKey, Supplier<SdkHttpClient> clientFactory) { + ManagedHttpClient managedClient = + clientMap.computeIfAbsent( + clientKey, + k -> { + LOG.debug("Creating new managed HTTP client for key: {}", k); + SdkHttpClient httpClient = clientFactory.get(); + return new ManagedHttpClient(httpClient, k); + }); + // Return the cached ref-counted wrapper + return managedClient.acquire(); + } + + /** + * Release a reference to the HTTP client. When the reference count reaches zero, the client is + * closed and removed from the registry. + * + * @param clientKey the key identifying the client to release + */ + public void releaseClient(String clientKey) { + ManagedHttpClient managedClient = clientMap.get(clientKey); + if (managedClient != null) { + if (managedClient.release()) { + // Client was closed, remove from map + clientMap.remove(clientKey, managedClient); + } + } + } + + @VisibleForTesting + ConcurrentMap<String, ManagedHttpClient> clientMap() { + return clientMap; + } + + @VisibleForTesting + void shutdown() { + clientMap.values().forEach(ManagedHttpClient::forceClose); + clientMap.clear(); + } + + /** + * Managed HTTP client wrapper that provides reference counting for lifecycle management. The HTTP + * client is closed when the reference count reaches zero. + */ + static class ManagedHttpClient { + private final SdkHttpClient httpClient; + private final String clientKey; + private final AtomicInteger refCount = new AtomicInteger(0); + private volatile boolean closed = false; + private volatile WrappedSdkHttpClient wrapper; + + ManagedHttpClient(SdkHttpClient httpClient, String clientKey) { + this.httpClient = httpClient; + this.clientKey = clientKey; + this.wrapper = new WrappedSdkHttpClient(httpClient, clientKey); + LOG.debug("Created managed HTTP client: key={}", clientKey); + } + + /** + * Acquire a reference to the HTTP client, incrementing the reference count. + * + * @return the ref-counted wrapper client + * @throws IllegalStateException if the client has already been closed + */ + WrappedSdkHttpClient acquire() { + if (closed) { + throw new IllegalStateException("Cannot acquire closed HTTP client: " + clientKey); + } + int count = refCount.incrementAndGet(); + LOG.debug("Acquired HTTP client: key={}, refCount={}", clientKey, count); + return wrapper; + } + + /** + * Release a reference to the HTTP client, decrementing the reference count. If the count + * reaches zero, the client is closed. + * + * @return true if the client was closed, false otherwise + */ + boolean release() { + if (closed) { + LOG.warn("Attempted to release already closed HTTP client: key={}", clientKey); + return false; + } + + int count = refCount.decrementAndGet(); + LOG.debug("Released HTTP client: key={}, refCount={}", clientKey, count); + if (count == 0) { + return close(); + } else if (count < 0) { + LOG.error( + "HTTP client reference count went negative despite closed check: key={}, refCount={}", + clientKey, + count); + refCount.set(0); // Reset to prevent further corruption + } + return false; + } + + /** + * Close the HTTP client if not already closed. + * + * @return true if the client was closed by this call, false if already closed + */ + private boolean close() { + if (!closed) { + synchronized (this) { + if (!closed) { + closed = true; + LOG.debug("Closing HTTP client: key={}", clientKey); + try { + httpClient.close(); + return true; + } catch (Exception e) { + LOG.warn("Error closing HTTP client: key={}", clientKey, e); + } + } + } + } + return false; + } + + /** Force close the HTTP client regardless of reference count (for testing/shutdown). */ + void forceClose() { Review Comment: I'm not sure I follow why we need `forceClose()` when it just calls `close()`. The place that currently calls `forceClose()` can be updated to call `close()` directly -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
