Allow BasicHttpPoster to reuse HTTP connections

phase4-lib/src/main/java/com/helger/phase4/messaging/http/BasicHttpPoster.java

@@ -80,6 +80,7 @@
 
   // By default no special SSL context present
   private HttpClientFactory m_aHttpClientFactory = createDefaultHttpClientFactory ();
+  private HttpClientManager m_aSharedHttpClientManager;
   private Consumer <? super HttpPost> m_aHttpCustomizer;
   private boolean m_bQuoteHttpHeaders = DEFAULT_QUOTE_HTTP_HEADERS;
 
@@ -100,6 +101,35 @@
     return this;
   }
 
+  /**
+   * @return The shared HTTP client manager used for all requests, or <code>null</code> if every
+   *         request should use a new manager. The returned manager is never closed by this class.
+   * @since 4.5.5
+   */
+  @Nullable
+  public final HttpClientManager getSharedHttpClientManager ()
+  {
+    return m_aSharedHttpClientManager;
+  }
+
+  /**
+   * Set a shared HTTP client manager to reuse connections across requests. The caller owns the
+   * manager and must close it after this poster is no longer used. A shared manager must not be
+   * closed while requests are running. Pass <code>null</code> to restore the default behavior of
+   * creating and closing a manager per request.
+   *
+   * @param aSharedHttpClientManager
+   *        The shared HTTP client manager to use. May be <code>null</code>.
+   * @return this for chaining
+   * @since 4.5.5
+   */
+  @NonNull
+  public final BasicHttpPoster setSharedHttpClientManager (@Nullable @WillNotClose final HttpClientManager aSharedHttpClientManager)
+  {
+    m_aSharedHttpClientManager = aSharedHttpClientManager;
+    return this;
+  }
+
   @Nullable
   public final Consumer <? super HttpPost> getHttpCustomizer ()
   {
@@ -147,7 +177,7 @@
    */
   @Nullable
   @Deprecated (forRemoval = true, since = "4.5.1")
   public <T> T sendGenericMessage (@NonNull @Nonempty final String sURL,
                                    @Nullable final HttpHeaderMap aCustomHttpHeaders,
                                    @NonNull final HttpEntity aHttpEntity,
                                    @NonNull final HttpClientResponseHandler <? extends T> aResponseHandler) throws IOException
@@ -194,58 +224,25 @@
     LOGGER.info ("Starting to transmit AS4 Message to '" + sURL + "'");
 
     IOException aCaughtException = null;
-    try (final HttpClientManager aClientMgr = new HttpClientManager (m_aHttpClientFactory))
+    try
     {
-      final HttpPost aPost = new HttpPost (sURL);
-
-      if (aCustomHttpHeaders != null)
+      if (m_aSharedHttpClientManager != null)
+        return _sendGenericMessageWithClientManager (sURL,
+                                                     aCustomHttpHeaders,
+                                                     aHttpEntity,
+                                                     aResponseHandler,
+                                                     aRemoteTlsPeerCertConsumer,
+                                                     m_aSharedHttpClientManager);
+
+      try (final HttpClientManager aClientMgr = new HttpClientManager (m_aHttpClientFactory))
       {
-        // Always unify line endings
-        // By default quoting is disabled
-        aCustomHttpHeaders.forEachSingleHeader (aPost::addHeader, true, m_bQuoteHttpHeaders);
+        return _sendGenericMessageWithClientManager (sURL,
+                                                     aCustomHttpHeaders,
+                                                     aHttpEntity,
+                                                     aResponseHandler,
+                                                     aRemoteTlsPeerCertConsumer,
+                                                     aClientMgr);
       }
-
-      aPost.setEntity (aHttpEntity);
-
-      // Invoke optional customizer
-      if (m_aHttpCustomizer != null)
-        m_aHttpCustomizer.accept (aPost);
-
-      // Debug sending
-      AS4HttpDebug.debug ( () -> {
-        final StringBuilder ret = new StringBuilder ("SEND-START to ").append (sURL).append ("\n");
-        try
-        {
-          for (final Header aHeader : aPost.getHeaders ())
-            ret.append (aHeader.getName ()).append (": ").append (aHeader.getValue ()).append (CHttp.EOL);
-          ret.append (CHttp.EOL);
-          if (aHttpEntity.isRepeatable ())
-            ret.append (EntityUtils.toString (aHttpEntity));
-          else
-            ret.append ("## The payload is marked as 'not repeatable' and is the therefore not printed in debugging");
-        }
-        catch (final Exception ex)
-        {
-          ret.append ("## Exception listing payload: " + ex.getClass ().getName () + " -- " + ex.getMessage ())
-             .append (CHttp.EOL);
-          ret.append ("## ").append (StackTraceHelper.getStackAsString (ex));
-        }
-        return ret.toString ();
-      });
-
-      // Execute main HTTP request
-      final HttpClientContext aHttpClientContext = HttpClientContext.create ();
-      final T ret = aClientMgr.execute (aPost, aHttpClientContext, aResponseHandler);
-
-      // Surface the TLS peer (server) certificates if requested. The
-      // CapturingTlsSocketStrategy is wired in by HttpClientFactory by default.
-      if (aRemoteTlsPeerCertConsumer != null)
-      {
-        final ICommonsList <X509Certificate> aRemoteTlsCerts = CapturingTlsSocketStrategy.getRemoteTLSCertificates (aHttpClientContext);
-        aRemoteTlsPeerCertConsumer.accept (aRemoteTlsCerts);
-      }
-
-      return ret;
     }
     catch (final IOException ex)
     {
@@ -272,6 +269,66 @@
     }
   }
 
+  @Nullable
+  private <T> T _sendGenericMessageWithClientManager (@NonNull @Nonempty final String sURL,
+                                                      @Nullable final HttpHeaderMap aCustomHttpHeaders,
+                                                      @NonNull final HttpEntity aHttpEntity,
+                                                      @NonNull final HttpClientResponseHandler <? extends T> aResponseHandler,
+                                                      @Nullable final Consumer <? super ICommonsList <X509Certificate>> aRemoteTlsPeerCertConsumer,
+                                                      @NonNull final HttpClientManager aClientMgr) throws IOException
+  {
+    final HttpPost aPost = new HttpPost (sURL);
+
+    if (aCustomHttpHeaders != null)
+    {
+      // Always unify line endings
+      // By default quoting is disabled
+      aCustomHttpHeaders.forEachSingleHeader (aPost::addHeader, true, m_bQuoteHttpHeaders);
+    }
+
+    aPost.setEntity (aHttpEntity);
+
+    // Invoke optional customizer
+    if (m_aHttpCustomizer != null)
+      m_aHttpCustomizer.accept (aPost);
+
+    // Debug sending
+    AS4HttpDebug.debug ( () -> {
+      final StringBuilder ret = new StringBuilder ("SEND-START to ").append (sURL).append ("\n");
+      try
+      {
+        for (final Header aHeader : aPost.getHeaders ())
+          ret.append (aHeader.getName ()).append (": ").append (aHeader.getValue ()).append (CHttp.EOL);
+        ret.append (CHttp.EOL);
+        if (aHttpEntity.isRepeatable ())
+          ret.append (EntityUtils.toString (aHttpEntity));
+        else
+          ret.append ("## The payload is marked as 'not repeatable' and is the therefore not printed in debugging");
+      }
+      catch (final Exception ex)
+      {
+        ret.append ("## Exception listing payload: " + ex.getClass ().getName () + " -- " + ex.getMessage ())
+           .append (CHttp.EOL);
+        ret.append ("## ").append (StackTraceHelper.getStackAsString (ex));
+      }
+      return ret.toString ();
+    });
+
+    // Execute main HTTP request
+    final HttpClientContext aHttpClientContext = HttpClientContext.create ();
+    final T ret = aClientMgr.execute (aPost, aHttpClientContext, aResponseHandler);
+
+    // Surface the TLS peer (server) certificates if requested. The
+    // CapturingTlsSocketStrategy is wired in by HttpClientFactory by default.
+    if (aRemoteTlsPeerCertConsumer != null)
+    {
+      final ICommonsList <X509Certificate> aRemoteTlsCerts = CapturingTlsSocketStrategy.getRemoteTLSCertificates (aHttpClientContext);
+      aRemoteTlsPeerCertConsumer.accept (aRemoteTlsCerts);
+    }
+
+    return ret;
+  }
+
   @NonNull
   protected static HttpEntity createDumpingHttpEntity (@Nullable final IAS4OutgoingDumper aOutgoingDumper,
                                                        @NonNull final HttpEntity aSrcEntity,
@@ -327,7 +384,7 @@
 
   @Nullable
   @Deprecated (forRemoval = true, since = "4.5.1")
   public <T> T sendGenericMessageWithRetries (@NonNull final String sURL,
                                               @Nullable final HttpHeaderMap aCustomHttpHeaders,
                                               @NonNull final HttpEntity aHttpEntity,
                                               @NonNull final String sMessageID,

phase4-lib/src/test/java/com/helger/phase4/messaging/http/BasicHttpPosterTest.java

@@ -0,0 +1,91 @@
+/*
+ * Copyright (C) 2026 Philip Helger (www.helger.com)
+ * philip[at]helger[dot]com
+ *
+ * Licensed 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 com.helger.phase4.messaging.http;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertSame;
+
+import java.io.IOException;
+import java.net.InetSocketAddress;
+import java.nio.charset.StandardCharsets;
+import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
+
+import org.apache.hc.core5.http.ContentType;
+import org.apache.hc.core5.http.io.entity.EntityUtils;
+import org.apache.hc.core5.http.io.entity.StringEntity;
+import org.junit.Test;
+
+import com.helger.httpclient.HttpClientFactory;
+import com.helger.httpclient.HttpClientManager;
+import com.sun.net.httpserver.HttpServer;
+
+/**
+ * Test class for class {@link BasicHttpPoster}.
+ *
+ * @author Greg Taube
+ */
+public final class BasicHttpPosterTest
+{
+  @Test
+  public void testSharedHttpClientManagerReusesConnection () throws IOException
+  {
+    final Set <Integer> aRemotePorts = ConcurrentHashMap.newKeySet ();
+    final HttpServer aServer = HttpServer.create (new InetSocketAddress ("127.0.0.1", 0), 0);
+    aServer.createContext ("/", aExchange -> {
+      aRemotePorts.add (Integer.valueOf (aExchange.getRemoteAddress ().getPort ()));
+      aExchange.getRequestBody ().readAllBytes ();
+      final byte [] aResponse = "ok".getBytes (StandardCharsets.UTF_8);
+      aExchange.sendResponseHeaders (200, aResponse.length);
+      aExchange.getResponseBody ().write (aResponse);
+      aExchange.close ();
+    });
+    aServer.start ();
+
+    final HttpClientManager aHttpClientManager = new HttpClientManager (new HttpClientFactory ());
+    try
+    {
+      final BasicHttpPoster aPoster = new BasicHttpPoster ();
+      assertNull (aPoster.getSharedHttpClientManager ());
+      assertSame (aPoster, aPoster.setSharedHttpClientManager (aHttpClientManager));
+      assertSame (aHttpClientManager, aPoster.getSharedHttpClientManager ());
+
+      final String sURL = "http://127.0.0.1:" + aServer.getAddress ().getPort () + '/';
+      assertEquals ("ok", _send (aPoster, sURL));
+      assertEquals ("ok", _send (aPoster, sURL));
+
+      assertEquals (1, aRemotePorts.size ());
+      assertFalse (aHttpClientManager.isClosed ());
+    }
+    finally
+    {
+      aHttpClientManager.close ();
+      aServer.stop (0);
+    }
+  }
+
+  private static String _send (final BasicHttpPoster aPoster, final String sURL) throws IOException
+  {
+    return aPoster.sendGenericMessage (sURL,
+                                       null,
+                                       new StringEntity ("request", ContentType.TEXT_PLAIN),
+                                       aResponse -> EntityUtils.toString (aResponse.getEntity ()),
+                                       null);
+  }
+}