Adding support to handle lengthy error msgs more precisely

Signed-off-by: Shruthi Manavalli Ramanna <shruthimanavalli.ramanna@bosch-si.com>

hawkbit-autoconfigure/src/main/java/org/eclipse/hawkbit/autoconfigure/dmf/amqp/DmfApiAutoConfiguration.java

@@ -27,13 +27,12 @@ public class DmfApiAutoConfiguration {
 
     /**
      * Create default error handler bean.
-     * 
+     *
      * @return the default error handler bean
      */
     @Bean
     @ConditionalOnMissingBean
     public ErrorHandler errorHandler() {
         return new ConditionalRejectingErrorHandler();
     }
-
 }

hawkbit-dmf/hawkbit-dmf-amqp/src/main/java/org/eclipse/hawkbit/amqp/AbstractAmqpErrorHandler.java

@@ -0,0 +1,48 @@
+/**
+ * Copyright (c) 2021 Bosch.IO GmbH and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ */
+package org.eclipse.hawkbit.amqp;
+
+import org.springframework.amqp.AmqpRejectAndDontRequeueException;
+
+/**
+ * An abstract error handler for errors resulting from AMQP.
+ */
+public abstract class AbstractAmqpErrorHandler<T> implements AmqpErrorHandler{
+
+    @Override
+    public void doHandle(Throwable throwable, AmqpErrorHandlerChain chain) {
+        // retrieving the cause of throwable as it contains the actual class of
+        // exception
+        final Throwable cause = throwable.getCause();
+        if (getExceptionClass().isAssignableFrom(cause.getClass())) {
+            throw new AmqpRejectAndDontRequeueException(getErrorMessage(throwable));
+        } else {
+            chain.handle(throwable);
+        }
+    }
+
+    /**
+     * Returns the class of the exception.
+     *
+     * @return
+     *          the exception class
+     */
+    public abstract Class<T> getExceptionClass();
+
+    /**
+     * Returns the customized error message.
+     *
+     * @return
+     *          the customized error message
+     */
+    public String getErrorMessage(Throwable throwable){
+      return AmqpErrorMessageComposer.constructErrorMessage(throwable);
+    }
+
+}

hawkbit-dmf/hawkbit-dmf-amqp/src/main/java/org/eclipse/hawkbit/amqp/AmqpConfiguration.java

@@ -8,9 +8,7 @@
  */
 package org.eclipse.hawkbit.amqp;
 
-import java.time.Duration;
-import java.util.Map;
-
+import com.google.common.collect.Maps;
 import org.eclipse.hawkbit.api.ArtifactUrlHandler;
 import org.eclipse.hawkbit.api.HostnameResolver;
 import org.eclipse.hawkbit.cache.DownloadIdCache;
@@ -53,7 +51,9 @@
 import org.springframework.retry.support.RetryTemplate;
 import org.springframework.util.ErrorHandler;
 
-import com.google.common.collect.Maps;
+import java.time.Duration;
+import java.util.List;
+import java.util.Map;
 
 /**
  * Spring configuration for AMQP based DMF communication for indirect device
@@ -80,15 +80,48 @@ public class AmqpConfiguration {
     private ServiceMatcher serviceMatcher;
 
     /**
-     * Register the bean for the custom error handler.
+     * Creates a custom error handler bean.
+     *
+     *  @param handlers
+     *                  list of {@link AmqpErrorHandler} handlers
+
+     * @return the delegating error handler bean
+     */
+    @Bean
+    @ConditionalOnMissingBean
+    public ErrorHandler errorHandler(final List<AmqpErrorHandler> handlers) {
+        return new DelegatingConditionalErrorHandler(handlers, new ConditionalRejectingErrorHandler(
+                new DelayedRequeueExceptionStrategy(amqpProperties.getRequeueDelay())));
+    }
+
+    /**
+     * Error handler bean for all target attributes related fatal errors
+     *
+     * @return the invalid target attribute exception handler bean
+     */
+    @Bean
+    public AmqpErrorHandler invalidTargetAttributeConditionalExceptionHandler() {
+        return new InvalidTargetAttributeExceptionHandler();
+    }
+
+    /**
+     * Error handler bean for entity not found errors
+     *
+     * @return the entity not found exception handler bean
+     */
+    @Bean
+    public AmqpErrorHandler entityNotFoundExceptionHandler() {
+        return new EntityNotFoundExceptionHandler();
+    }
+
+    /**
+     * Error handler bean for amqp message conversion errors
      *
-     * @return custom error handler
+     * @return the amqp message conversion exception handler bean
      */
     @Bean
-    @ConditionalOnMissingBean(ErrorHandler.class)
-    public ErrorHandler errorHandler() {
-        return new ConditionalRejectingErrorHandler(
-                new DelayedRequeueExceptionStrategy(amqpProperties.getRequeueDelay()));
+    public AmqpErrorHandler messageConversionExceptionHandler() {
+        return new MessageConversionExceptionHandler();
     }
 
     /**

hawkbit-dmf/hawkbit-dmf-amqp/src/main/java/org/eclipse/hawkbit/amqp/AmqpErrorHandler.java

@@ -0,0 +1,28 @@
+/**
+ * Copyright (c) 2021 Bosch.IO GmbH and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ */
+package org.eclipse.hawkbit.amqp;
+
+/**
+ * Interface declaration of {@link AmqpErrorHandler} that handles errors based on the
+ * types of exception.
+ */
+@FunctionalInterface
+public interface AmqpErrorHandler {
+
+    /**
+     * Handles the error based on the type of exception
+     *
+     * @param throwable
+     *            the throwable
+     * @param chain
+     *            an {@link AmqpErrorHandlerChain}
+     */
+void doHandle(final Throwable throwable, final AmqpErrorHandlerChain chain);
+
+}

hawkbit-dmf/hawkbit-dmf-amqp/src/main/java/org/eclipse/hawkbit/amqp/AmqpErrorHandlerChain.java

@@ -0,0 +1,64 @@
+/**
+ * Copyright (c) 2021 Bosch.IO GmbH and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ */
+package org.eclipse.hawkbit.amqp;
+
+import org.springframework.util.ErrorHandler;
+
+import java.util.Iterator;
+import java.util.List;
+
+/**
+ * An error handler chain that delegates the error to the matching error handler based on the type of exception
+ */
+public final class AmqpErrorHandlerChain {
+    private final Iterator<AmqpErrorHandler> iterator;
+    private final ErrorHandler defaultHandler;
+
+    /**
+     * Constructor
+     *
+     * @param iterator
+     *                  the {@link AmqpErrorHandler} iterator
+     * @param defaultHandler
+     *                  the default handler
+     */
+   private AmqpErrorHandlerChain(Iterator<AmqpErrorHandler> iterator, ErrorHandler defaultHandler) {
+        this.iterator = iterator;
+        this.defaultHandler = defaultHandler;
+    }
+
+    /**
+     * Returns an {@link AmqpErrorHandlerChain}
+     *
+     * @param errorHandlers
+     *                      {@link List} of error handlers
+     * @param defaultHandler
+     *                      the default error handler
+     * @return an {@link AmqpErrorHandlerChain}
+     */
+    public static AmqpErrorHandlerChain getHandlerChain(final List<AmqpErrorHandler> errorHandlers, final ErrorHandler defaultHandler) {
+        return new AmqpErrorHandlerChain(errorHandlers.iterator(), defaultHandler);
+    }
+
+    /**
+     * Handles the error based on the type of exception
+     *
+     * @param error
+     *               the throwable containing the cause of exception
+     */
+    public void handle(final Throwable error) {
+        if (iterator.hasNext()) {
+            final AmqpErrorHandler handler = iterator.next();
+            handler.doHandle(error, this);
+        } else {
+            defaultHandler.handleError(error);
+        }
+    }
+}
+

hawkbit-dmf/hawkbit-dmf-amqp/src/main/java/org/eclipse/hawkbit/amqp/AmqpErrorMessageComposer.java

@@ -0,0 +1,53 @@
+/**
+ * Copyright (c) 2021 Bosch.IO GmbH and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ */
+package org.eclipse.hawkbit.amqp;
+
+import java.util.Collection;
+import java.util.Map;
+import java.util.stream.Collectors;
+
+import org.springframework.amqp.core.Message;
+import org.springframework.amqp.rabbit.support.ListenerExecutionFailedException;
+
+/**
+ * Class that composes a meaningful error message and enhances it with properties from failed message
+ */
+public class AmqpErrorMessageComposer {
+
+    private AmqpErrorMessageComposer() {
+    }
+
+    /**
+     * Constructs an error message based on failed message content
+     *
+     * @param throwable
+     *                  the throwable containing failed message content
+     * @return
+     *                  meaningful error message
+     */
+    public static String constructErrorMessage(final Throwable throwable) {
+        StringBuilder completeErrorMessage = new StringBuilder();
+        final String mainErrorMsg = throwable.getCause().getMessage();
+
+        if (throwable instanceof ListenerExecutionFailedException) {
+            Collection<Message> failedMessages = ((ListenerExecutionFailedException) throwable).getFailedMessages();
+            // since the intended message content is always on top of the collection, we only extract the first one
+            final Message failedMessage = failedMessages.iterator().next();
+            final byte[] amqpFailedMsgBody = failedMessage.getBody();
+            final Map<String, Object> amqpFailedMsgHeaders = failedMessage.getMessageProperties().getHeaders();
+
+            String amqpFailedMsgConcatenatedHeaders = amqpFailedMsgHeaders.keySet().stream()
+                    .map(key -> key + "=" + amqpFailedMsgHeaders.get(key)).collect(Collectors.joining(", ", "{", "}"));
+            completeErrorMessage.append(mainErrorMsg).append(new String(amqpFailedMsgBody))
+                    .append(amqpFailedMsgConcatenatedHeaders);
+            return completeErrorMessage.toString();
+        }
+        return mainErrorMsg;
+    }
+}

hawkbit-dmf/hawkbit-dmf-amqp/src/main/java/org/eclipse/hawkbit/amqp/DelegatingConditionalErrorHandler.java

@@ -0,0 +1,40 @@
+/**
+ * Copyright (c) 2021 Bosch.IO GmbH and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ */
+package org.eclipse.hawkbit.amqp;
+
+import java.util.List;
+import javax.validation.constraints.NotNull;
+
+import org.springframework.util.ErrorHandler;
+
+/**
+ * An error handler delegates error handling to the matching {@link AmqpErrorHandler} based on the type of exception
+ */
+public class DelegatingConditionalErrorHandler implements ErrorHandler {
+    private final List<AmqpErrorHandler> handlers;
+    private final ErrorHandler defaultHandler;
+
+    /**
+     * Constructor
+     *
+     * @param handlers
+     *                 {@link List} of error handlers
+     * @param defaultHandler
+     *                  the default error handler
+     */
+    public DelegatingConditionalErrorHandler(final List<AmqpErrorHandler> handlers, @NotNull final ErrorHandler defaultHandler) {
+        this.handlers = handlers;
+        this.defaultHandler = defaultHandler;
+    }
+
+    @Override
+    public void handleError(final Throwable t) {
+        AmqpErrorHandlerChain.getHandlerChain(handlers, defaultHandler).handle(t);
+    }
+}

hawkbit-dmf/hawkbit-dmf-amqp/src/main/java/org/eclipse/hawkbit/amqp/EntityNotFoundExceptionHandler.java

@@ -0,0 +1,22 @@
+/**
+ * Copyright (c) 2021 Bosch.IO GmbH and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ */
+package org.eclipse.hawkbit.amqp;
+
+import org.eclipse.hawkbit.repository.exception.EntityNotFoundException;
+
+/**
+ * An error handler for entity not found exception resulting from AMQP.
+ */
+public class EntityNotFoundExceptionHandler extends AbstractAmqpErrorHandler<EntityNotFoundException> {
+
+    @Override
+    public Class<EntityNotFoundException> getExceptionClass() {
+        return EntityNotFoundException.class;
+    }
+}

hawkbit-dmf/hawkbit-dmf-amqp/src/main/java/org/eclipse/hawkbit/amqp/InvalidTargetAttributeExceptionHandler.java

@@ -0,0 +1,22 @@
+/**
+ * Copyright (c) 2021 Bosch.IO GmbH and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ */
+package org.eclipse.hawkbit.amqp;
+
+import org.eclipse.hawkbit.repository.exception.InvalidTargetAttributeException;
+
+/**
+ * An error handler for all invalid target attributes resulting from AMQP.
+ */
+public class InvalidTargetAttributeExceptionHandler extends AbstractAmqpErrorHandler<InvalidTargetAttributeException> {
+
+    @Override
+    public Class<InvalidTargetAttributeException> getExceptionClass() {
+        return InvalidTargetAttributeException.class;
+    }
+}