Add post-processor for AMQP connection factory

For advanced customization (TLS, metrics, threading, etc), just before
the AMQP connection is created.

Fixes #57

(cherry picked from commit da91f5d)

Conflicts:
	src/main/java/com/rabbitmq/jms/admin/RMQConnectionFactory.java

Author: acogoluegnes

src/main/java/com/rabbitmq/jms/admin/RMQConnectionFactory.java

@@ -4,6 +4,7 @@
 import com.rabbitmq.client.Address;
 import com.rabbitmq.client.MetricsCollector;
 import com.rabbitmq.client.NoOpMetricsCollector;
+import com.rabbitmq.jms.client.AmqpConnectionFactoryPostProcessor;
 import com.rabbitmq.jms.client.AmqpPropertiesCustomiser;
 import com.rabbitmq.jms.client.ConnectionParams;
 import com.rabbitmq.jms.client.RMQConnection;
@@ -107,6 +108,17 @@ public class RMQConnectionFactory implements ConnectionFactory, Referenceable, S
      */
     private MetricsCollector metricsCollector = new NoOpMetricsCollector();
 
+    /**
+     * For post-processor the {@link com.rabbitmq.client.ConnectionFactory} before creating the AMQP connection.
+     *
+     * @since 1.10.0
+     */
+    private AmqpConnectionFactoryPostProcessor amqpConnectionFactoryPostProcessor = new AmqpConnectionFactoryPostProcessor() {
+
+        @Override
+        public void postProcess(com.rabbitmq.client.ConnectionFactory connectionFactory) { }
+    };
+
     /** Default not to use ssl */
     private boolean ssl = false;
     private String tlsProtocol;
@@ -222,6 +234,9 @@ protected Connection createConnection(String username, String password, Connecti
         maybeEnableTLS(cf);
         maybeEnableHostnameVerification(cf);
         cf.setMetricsCollector(this.metricsCollector);
+        if (this.amqpConnectionFactoryPostProcessor != null) {
+            this.amqpConnectionFactoryPostProcessor.postProcess(cf);
+        }
         com.rabbitmq.client.Connection rabbitConnection = instantiateNodeConnection(cf, connectionCreator);
 
         RMQConnection conn = new RMQConnection(new ConnectionParams()
@@ -859,6 +874,20 @@ public List<String> getUris() {
         return urisAsStrings;
     }
 
+    /**
+     * Set a post-processor for the AMQP {@link com.rabbitmq.client.ConnectionFactory}.
+     * <p>
+     * The post-processor is called before the AMQP creation. This callback can be
+     * useful to customize the {@link com.rabbitmq.client.ConnectionFactory}:
+     * TLS-related configuration, metrics collection, etc.
+     *
+     * @param amqpConnectionFactoryPostProcessor
+     * @since 1.10.0
+     */
+    public void setAmqpConnectionFactoryPostProcessor(AmqpConnectionFactoryPostProcessor amqpConnectionFactoryPostProcessor) {
+        this.amqpConnectionFactoryPostProcessor = amqpConnectionFactoryPostProcessor;
+    }
+
     private interface ConnectionCreator {
         com.rabbitmq.client.Connection create(com.rabbitmq.client.ConnectionFactory cf) throws Exception;
     }

src/main/java/com/rabbitmq/jms/client/AmqpConnectionFactoryPostProcessor.java

@@ -0,0 +1,24 @@
+/* Copyright (c) 2018 Pivotal Software, Inc. All rights reserved. */
+
+package com.rabbitmq.jms.client;
+
+import com.rabbitmq.client.ConnectionFactory;
+
+/**
+ * Callback to post-process the AMQP {@link com.rabbitmq.client.ConnectionFactory}.
+ *
+ * <p>
+ * This callback is enforced just before the creation of the AMQP connection.
+ * It can be used to for any customisation: TLS, threading, etc.
+ *
+ * @since 1.10.0
+ */
+public interface AmqpConnectionFactoryPostProcessor {
+
+    /**
+     * Customise the {@link ConnectionFactory} before AMQP connection creation.
+     *
+     * @param connectionFactory
+     */
+    void postProcess(ConnectionFactory connectionFactory);
+}

src/main/java/com/rabbitmq/jms/client/AmqpPropertiesCustomiser.java

@@ -8,16 +8,17 @@
 
 /**
  * Callback to customise properties of outbound AMQP messages.
+ *
  * @since 1.9.0
  */
 public interface AmqpPropertiesCustomiser {
 
     /**
      * Customise AMQP message properties.
-     * @param builder the AMQP properties builder
+     *
+     * @param builder    the AMQP properties builder
      * @param jmsMessage the outbound JMS message
      * @return the customised or a new AMQP properties builder
      */
     AMQP.BasicProperties.Builder customise(AMQP.BasicProperties.Builder builder, Message jmsMessage);
-
 }

src/test/java/com/rabbitmq/jms/admin/RMQConnectionFactoryTest.java

@@ -6,6 +6,7 @@
 import com.rabbitmq.client.AddressResolver;
 import com.rabbitmq.client.Connection;
 import com.rabbitmq.client.ConnectionFactory;
+import com.rabbitmq.jms.client.AmqpConnectionFactoryPostProcessor;
 import org.hamcrest.Matchers;
 import org.junit.Before;
 import org.junit.Test;
@@ -19,6 +20,7 @@
 import java.util.List;
 import java.util.Properties;
 import java.util.concurrent.ExecutorService;
+import java.util.concurrent.atomic.AtomicInteger;
 
 import static java.util.Arrays.asList;
 import static org.hamcrest.Matchers.both;
@@ -274,6 +276,21 @@ public void shouldUseSeveralAddressesWhenUrisIsUsed() throws Exception {
         assertEquals(10000, passedInAddressResolver.getAddresses().get(1).getPort());
     }
 
+    @Test public void amqpConnectionFactoryIsCalled() throws Exception {
+        final AtomicInteger callCount = new AtomicInteger(0);
+        rmqCf.setAmqpConnectionFactoryPostProcessor(new AmqpConnectionFactoryPostProcessor() {
+
+            @Override
+            public void postProcess(ConnectionFactory cf) {
+                callCount.incrementAndGet();
+            }
+        });
+        rmqCf.createConnection();
+        assertEquals(1, callCount.get());
+        rmqCf.createConnection();
+        assertEquals(2, callCount.get());
+    }
+
     class TestRmqConnectionFactory extends RMQConnectionFactory {
 
         @Override