From acc5bcc4240f97c23293b4873e6715d2ea84821b Mon Sep 17 00:00:00 2001
From: Timothy Bish <tabish121@gmail.com>
Date: Tue, 3 Mar 2026 14:19:14 -0500
Subject: [PATCH] ARTEMIS-5911 Ensure core federation ignores AMQP federation
 configuration

When parsing the Core federation XML elements we need to ensure that AMQP broker
connections with federation configuration does not get picked up as that creates
empty configuration entries in the broker configuration.
---
 .../impl/FileConfigurationParser.java         |  19 +-
 .../impl/FileConfigurationParserTest.java     | 192 ++++++++++++++++++
 2 files changed, 204 insertions(+), 7 deletions(-)

diff --git a/artemis-server/src/main/java/org/apache/activemq/artemis/core/deployers/impl/FileConfigurationParser.java b/artemis-server/src/main/java/org/apache/activemq/artemis/core/deployers/impl/FileConfigurationParser.java
index 30e64d6ae41..c75e2dc1e6f 100644
--- a/artemis-server/src/main/java/org/apache/activemq/artemis/core/deployers/impl/FileConfigurationParser.java
+++ b/artemis-server/src/main/java/org/apache/activemq/artemis/core/deployers/impl/FileConfigurationParser.java
@@ -671,19 +671,24 @@ public void parseMainConfig(final Element e, final Configuration config) throws
          }
       }
 
+      // Ensure AMQP federation configuration isn't picked up here by core federation
+      // configuration parsing, any AMQP federation configuration would generate empty
+      // Core federation configurations that would not create active federations.
       NodeList federations = e.getElementsByTagName("federations");
 
       for (int i = 0; i < federations.getLength(); i++) {
-         Element fedNode = (Element) federations.item(i);
-         parseFederationsConfiguration(fedNode, config);
-      }
+         Element federationElement = (Element) federations.item(i);
 
-      NodeList fedNodes = e.getElementsByTagName("federation");
+         // Handle attributes at the federations level and then add each nested federation.
+         parseFederationsConfiguration(federationElement, config);
 
-      for (int i = 0; i < fedNodes.getLength(); i++) {
-         Element fedNode = (Element) fedNodes.item(i);
+         for (int j = 0; j < federationElement.getChildNodes().getLength(); ++j) {
+            Node node = federationElement.getChildNodes().item(j);
 
-         parseFederationConfiguration(fedNode, config);
+            if (node.getNodeName().equalsIgnoreCase("federation")) {
+               parseFederationConfiguration((Element) node, config);
+            }
+         }
       }
 
       NodeList gaNodes = e.getElementsByTagName("grouping-handler");
diff --git a/artemis-server/src/test/java/org/apache/activemq/artemis/core/config/impl/FileConfigurationParserTest.java b/artemis-server/src/test/java/org/apache/activemq/artemis/core/config/impl/FileConfigurationParserTest.java
index b820fd83b7f..7f85aaf4849 100644
--- a/artemis-server/src/test/java/org/apache/activemq/artemis/core/config/impl/FileConfigurationParserTest.java
+++ b/artemis-server/src/test/java/org/apache/activemq/artemis/core/config/impl/FileConfigurationParserTest.java
@@ -34,6 +34,8 @@
 import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.TimeUnit;
+import java.util.function.Function;
+import java.util.stream.Collectors;
 
 import org.apache.activemq.artemis.api.config.ActiveMQDefaultConfiguration;
 import org.apache.activemq.artemis.api.core.SimpleString;
@@ -501,6 +503,196 @@ public void testDefaultBridgeProducerWindowSize() throws Exception {
       assertEquals(ActiveMQDefaultConfiguration.getDefaultBridgeProducerWindowSize(), bconfig.getProducerWindowSize());
    }
 
+   @Test
+   public void testCoreFederationIgnoresAMQPFederationConfigurations() throws Exception {
+      FileConfigurationParser parser = new FileConfigurationParser();
+      String middlePart = """
+      <broker-connections>
+         <amqp-connection uri="tcp://test1:111" name="test1" retry-interval="333" reconnect-attempts="33" user="testuser" password="testpassword">
+            <federation>
+               <local-queue-policy name="federation5" priority-adjustment="1" include-federated="false">
+                  <include address-match="test" queue-match="tracking" />
+               </local-queue-policy>
+            </federation>
+         </amqp-connection>
+         <amqp-connection uri="tcp://federation" name="federation6" auto-start="false">
+            <federation>
+               <local-queue-policy name="lqp1" priority-adjustment="1" include-federated="false">
+                  <include address-match="test" queue-match="tracking" />
+                  <property key="amqpCredits" value="1"/>
+                  <transformer-class-name>class-another</transformer-class-name>
+               </local-queue-policy>
+                <remote-queue-policy name="rqp1" priority-adjustment="-1" include-federated="true">
+                  <include address-match="#" queue-match="tracking" />
+                  <property key="amqpCredits" value="2"/>
+                  <property key="amqpLowCredits" value="1"/>
+               </remote-queue-policy>
+               <local-address-policy name="lap1" auto-delete="false" auto-delete-delay="1" auto-delete-message-count="12" max-hops="2" enable-divert-bindings="true">
+                  <include address-match="orders" />
+                  <exclude address-match="all.#" />
+                  <transformer-class-name>class-name</transformer-class-name>
+               </local-address-policy>
+               <local-queue-policy name="lqp2">
+                  <include address-match="address" queue-match="theQueue" />
+                  <transformer-class-name>class-another</transformer-class-name>
+               </local-queue-policy>
+               <remote-address-policy name="rap1" auto-delete="true" auto-delete-delay="2" auto-delete-message-count="42" max-hops="1" enable-divert-bindings="false">
+                  <include address-match="support" />
+                  <property key="amqpCredits" value="2"/>
+                  <property key="amqpLowCredits" value="1"/>
+                  <transformer>
+                     <class-name>something</class-name>
+                     <property key="key1" value="value1"/>
+                     <property key="key2" value="value2"/>
+                  </transformer>
+               </remote-address-policy>
+               <property key="amqpCredits" value="7"/>
+               <property key="amqpLowCredits" value="1"/>
+            </federation>
+         </amqp-connection>
+      </broker-connections>
+      <federations>
+         <federation name="federation1">
+            <upstream name="eu-west-1" user="westuser" password="32a10275cf4ab4e9">
+               <static-connectors>
+                  <connector-ref>connector1</connector-ref>
+               </static-connectors>
+               <policy ref="policySetA"/>
+            </upstream>
+            <upstream name="eu-east-1" user="eastuser" password="32a10275cf4ab4e9">
+               <ha>true</ha>
+               <discovery-group-ref discovery-group-name="dg1"/>
+               <policy ref="policySetA"/>
+            </upstream>
+            <policy-set name="policySetA">
+               <policy ref="address-federation" />
+               <policy ref="queue-federation" />
+            </policy-set>
+            <queue-policy name="queue-federation" >
+               <exclude queue-match="the_queue" address-match="#" />
+            </queue-policy>
+            <address-policy name="address-federation" >
+               <include address-match="the_address" />
+            </address-policy>
+         </federation>
+         <federation name="federation2" user="globaluser" password="32a10275cf4ab4e9">
+            <upstream name="usa-west-1">
+               <static-connectors>
+                  <connector-ref>connector1</connector-ref>
+               </static-connectors>
+               <policy ref="address-federation-usa"/>
+            </upstream>
+            <upstream name="usa-east-1" >
+               <ha>true</ha>
+               <discovery-group-ref discovery-group-name="dg1"/>
+               <policy ref="queue-federation-usa"/>
+            </upstream>
+            <queue-policy name="queue-federation-usa" >
+               <exclude queue-match="the_queue" address-match="#" />
+            </queue-policy>
+            <address-policy name="address-federation-usa" >
+               <include address-match="the_address" />
+            </address-policy>
+         </federation>
+         <federation name="federation3" user="globaluser" password="32a10275cf4ab4e9">
+            <upstream name="asia-1">
+               <static-connectors>
+                  <connector-ref>connector1</connector-ref>
+               </static-connectors>
+               <policy ref="queue-federation-asia"/>
+               <policy ref="address-federation-asia"/>
+            </upstream>
+            <upstream name="asia-2" >
+               <ha>true</ha>
+               <discovery-group-ref discovery-group-name="dg1"/>
+               <policy ref="queue-federation-asia"/>
+               <policy ref="address-federation-asia"/>
+            </upstream>
+            <queue-policy name="queue-federation-asia" transformer-ref="federation-transformer-3" >
+               <exclude queue-match="the_queue" address-match="#" />
+            </queue-policy>
+            <address-policy name="address-federation-asia" transformer-ref="federation-transformer-3" >
+               <include address-match="the_address" />
+            </address-policy>
+            <transformer name="federation-transformer-3">
+               <class-name>org.foo.FederationTransformer3</class-name>
+               <property key="federationTransformerKey1" value="federationTransformerValue1"/>
+               <property key="federationTransformerKey2" value="federationTransformerValue2"/>
+            </transformer>
+         </federation>
+         <federation name="federation4" user="globaluser" password="32a10275cf4ab4e9">
+            <upstream name="asia-3">
+               <static-connectors>
+                  <connector-ref>connector1</connector-ref>
+               </static-connectors>
+               <policy ref="queue-federation-asia"/>
+               <policy ref="address-federation-asia"/>
+            </upstream>
+            <downstream name="asia-4" >
+               <ha>true</ha>
+               <discovery-group-ref discovery-group-name="dg1"/>
+               <policy ref="queue-federation-asia"/>
+               <policy ref="address-federation-asia"/>
+               <upstream-connector-ref>connector1</upstream-connector-ref>
+            </downstream>
+            <queue-policy name="queue-federation-asia2" transformer-ref="federation-transformer-4" >
+               <exclude queue-match="the_queue" address-match="#" />
+            </queue-policy>
+            <address-policy name="address-federation-asia2" transformer-ref="federation-transformer-4" >
+               <include address-match="the_address" />
+            </address-policy>
+            <transformer name="federation-transformer-4">
+               <class-name>org.foo.FederationTransformer4</class-name>
+               <property key="federationTransformerKey1" value="federationTransformerValue1"/>
+               <property key="federationTransformerKey2" value="federationTransformerValue2"/>
+            </transformer>
+         </federation>
+      </federations>""";
+
+      String configStr = FIRST_PART + middlePart + LAST_PART;
+      ByteArrayInputStream input = new ByteArrayInputStream(configStr.getBytes(StandardCharsets.UTF_8));
+
+      Configuration config = parser.parseMainConfig(input);
+
+      assertEquals(4, config.getFederationConfigurations().size());
+
+      final Map<String, FederationConfiguration> federations =
+         config.getFederationConfigurations().stream()
+                                             .collect(Collectors.toMap(c -> c.getName(), Function.identity()));
+
+      assertTrue(federations.containsKey("federation1"));
+
+      final FederationConfiguration configuration1 = federations.get("federation1");
+
+      assertEquals(2, configuration1.getUpstreamConfigurations().size());
+      assertEquals(0, configuration1.getDownstreamConfigurations().size());
+      assertEquals(0, configuration1.getTransformerConfigurations().size());
+
+      assertTrue(federations.containsKey("federation2"));
+
+      final FederationConfiguration configuration2 = federations.get("federation2");
+
+      assertEquals(2, configuration2.getUpstreamConfigurations().size());
+      assertEquals(0, configuration2.getDownstreamConfigurations().size());
+      assertEquals(0, configuration2.getTransformerConfigurations().size());
+
+      assertTrue(federations.containsKey("federation3"));
+
+      final FederationConfiguration configuration3 = federations.get("federation3");
+
+      assertEquals(2, configuration3.getUpstreamConfigurations().size());
+      assertEquals(0, configuration3.getDownstreamConfigurations().size());
+      assertEquals(1, configuration3.getTransformerConfigurations().size());
+
+      assertTrue(federations.containsKey("federation4"));
+
+      final FederationConfiguration configuration4 = federations.get("federation4");
+
+      assertEquals(1, configuration4.getUpstreamConfigurations().size());
+      assertEquals(1, configuration4.getDownstreamConfigurations().size());
+      assertEquals(1, configuration4.getTransformerConfigurations().size());
+   }
+
    @Test
    public void testParsingOverflowPageSize() throws Exception {
       testParsingOverFlow("""