[#2955] Fix MQTT5 Connect Reason Codes

MQTT5 defines new reason codes to be included in CONNACK packets when
connection establishment fails. The abstract adapter base class has been
changed accordingly.

Also added integration tests based on HiveMQ client for testing
connection establishment.

adapters/mqtt-base/src/main/java/org/eclipse/hono/adapter/mqtt/AbstractVertxBasedMqttProtocolAdapter.java

@@ -90,6 +90,7 @@
 import io.netty.handler.codec.mqtt.MqttConnectReturnCode;
 import io.netty.handler.codec.mqtt.MqttProperties;
 import io.netty.handler.codec.mqtt.MqttQoS;
+import io.netty.handler.codec.mqtt.MqttVersion;
 import io.opentracing.Span;
 import io.opentracing.SpanContext;
 import io.opentracing.log.Fields;
@@ -518,7 +519,7 @@ final void handleEndpointConnection(final MqttEndpoint endpoint) {
                     log.debug("rejecting connection request from client [clientId: {}], cause:",
                             endpoint.clientIdentifier(), t);
 
-                    final MqttConnectReturnCode code = getConnectReturnCode(t);
+                    final MqttConnectReturnCode code = getConnectReturnCode(t, endpoint);
                     rejectConnectionRequest(endpoint, code, span);
                     TracingHelper.logError(span, t);
                 }
@@ -1106,28 +1107,33 @@ final MqttDeviceEndpoint createMqttDeviceEndpoint(
         return mqttDeviceEndpoint;
     }
 
-    private static MqttConnectReturnCode getConnectReturnCode(final Throwable e) {
+    private static MqttConnectReturnCode getConnectReturnCode(final Throwable e, final MqttEndpoint endpoint) {
 
-        if (e instanceof MqttConnectionException) {
-            return ((MqttConnectionException) e).code();
+        final boolean isPreMqtt5 = ((int) MqttVersion.MQTT_5.protocolLevel()) > endpoint.protocolVersion();
+        if (e instanceof MqttConnectionException connectionException) {
+            return connectionException.code();
+        } else if (e instanceof AdapterConnectionsExceededException) {
+            return isPreMqtt5 ? MqttConnectReturnCode.CONNECTION_REFUSED_SERVER_UNAVAILABLE
+                    : MqttConnectReturnCode.CONNECTION_REFUSED_QUOTA_EXCEEDED;
         } else if (e instanceof AuthorizationException) {
-            if (e instanceof AdapterConnectionsExceededException) {
-                return MqttConnectReturnCode.CONNECTION_REFUSED_SERVER_UNAVAILABLE;
-            } else {
-                return MqttConnectReturnCode.CONNECTION_REFUSED_NOT_AUTHORIZED;
-            }
-        } else if (e instanceof ServiceInvocationException) {
-            switch (((ServiceInvocationException) e).getErrorCode()) {
+            return isPreMqtt5 ? MqttConnectReturnCode.CONNECTION_REFUSED_NOT_AUTHORIZED
+                    : MqttConnectReturnCode.CONNECTION_REFUSED_NOT_AUTHORIZED_5;
+        } else if (e instanceof ServiceInvocationException exception) {
+            switch (exception.getErrorCode()) {
             case HttpURLConnection.HTTP_UNAUTHORIZED:
             case HttpURLConnection.HTTP_NOT_FOUND:
-                return MqttConnectReturnCode.CONNECTION_REFUSED_BAD_USER_NAME_OR_PASSWORD;
+                return isPreMqtt5 ? MqttConnectReturnCode.CONNECTION_REFUSED_BAD_USER_NAME_OR_PASSWORD
+                        : MqttConnectReturnCode.CONNECTION_REFUSED_BAD_USERNAME_OR_PASSWORD;
             case HttpURLConnection.HTTP_UNAVAILABLE:
-                return MqttConnectReturnCode.CONNECTION_REFUSED_SERVER_UNAVAILABLE;
+                return isPreMqtt5 ? MqttConnectReturnCode.CONNECTION_REFUSED_SERVER_UNAVAILABLE
+                        : MqttConnectReturnCode.CONNECTION_REFUSED_SERVER_UNAVAILABLE_5;
             default:
-                return MqttConnectReturnCode.CONNECTION_REFUSED_NOT_AUTHORIZED;
+                return isPreMqtt5 ? MqttConnectReturnCode.CONNECTION_REFUSED_NOT_AUTHORIZED
+                        : MqttConnectReturnCode.CONNECTION_REFUSED_NOT_AUTHORIZED_5;
             }
         } else {
-            return MqttConnectReturnCode.CONNECTION_REFUSED_NOT_AUTHORIZED;
+            return isPreMqtt5 ? MqttConnectReturnCode.CONNECTION_REFUSED_NOT_AUTHORIZED
+                    : MqttConnectReturnCode.CONNECTION_REFUSED_UNSPECIFIED_ERROR;
         }
     }
 

bom/pom.xml

@@ -595,6 +595,11 @@ quarkus.vertx.max-event-loop-execute-time=${max.event-loop.execute-time:20000}
       </dependency>
 
       <!-- Testing -->
+      <dependency>
+        <groupId>com.hivemq</groupId>
+        <artifactId>hivemq-mqtt-client</artifactId>
+        <version>1.3.3</version>
+      </dependency>
       <dependency>
         <groupId>org.eclipse.hono</groupId>
         <artifactId>core-test-utils</artifactId>

tests/pom.xml

@@ -319,6 +319,10 @@
       <artifactId>vertx-mqtt</artifactId>
       <scope>test</scope>
     </dependency>
+    <dependency>
+      <groupId>com.hivemq</groupId>
+      <artifactId>hivemq-mqtt-client</artifactId>
+    </dependency>
     <dependency>
       <groupId>org.eclipse.californium</groupId>
       <artifactId>californium-core</artifactId>

tests/src/test/java/org/eclipse/hono/tests/mqtt/MqttTestBase.java

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2016, 2023 Contributors to the Eclipse Foundation
+ * Copyright (c) 2023 Contributors to the Eclipse Foundation
  *
  * See the NOTICE file(s) distributed with this work for additional
  * information regarding copyright ownership.
@@ -36,7 +36,7 @@
 import io.vertx.mqtt.messages.MqttConnAckMessage;
 
 /**
- * Base class for MQTT adapter integration tests.
+ * Base class for MQTT adapter integration tests using MQTT 3.1.1.
  *
  */
 public abstract class MqttTestBase {
@@ -70,7 +70,7 @@ public abstract class MqttTestBase {
     protected Context context;
 
     /**
-     * Creates default AMQP client options.
+     * Creates default MQTT client options.
      */
     @BeforeAll
     public static void init() {