2 * ===============================LICENSE_START======================================
4 * ================================================================================
5 * Copyright © 2017 AT&T Intellectual Property. All rights reserved.
6 * ================================================================================
7 * Licensed under the Apache License, Version 2.0 (the "License");
8 * you may not use this file except in compliance with the License.
9 * You may obtain a copy of the License at
11 * http://www.apache.org/licenses/LICENSE-2.0
13 * Unless required by applicable law or agreed to in writing, software
14 * distributed under the License is distributed on an "AS IS" BASIS,
15 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16 * See the License for the specific language governing permissions and
17 * limitations under the License.
18 * ============================LICENSE_END===========================================
21 package org.openecomp.dcae.apod.analytics.common.service.processor;
23 import com.google.common.base.Optional;
24 import org.openecomp.dcae.apod.analytics.common.exception.MessageProcessingException;
25 import org.slf4j.Logger;
26 import org.slf4j.LoggerFactory;
28 import javax.annotation.Nonnull;
30 import static java.lang.String.format;
33 * An abstract Message Processor which can be extended by {@link MessageProcessor} implementations
34 * to get default behavior for Message Processors
36 * @param <P> Processor Context sub classes
38 * @author Rajiv Singla . Creation Date: 11/8/2016.
40 public abstract class AbstractMessageProcessor<P extends ProcessorContext> implements MessageProcessor<P> {
42 private static final Logger LOG = LoggerFactory.getLogger(AbstractMessageProcessor.class);
45 * By Default there is no processing message
47 private String processingMessage = null;
50 * By Default Processing State is set to not required - subclasses must
51 * set processing state to {@link ProcessingState#PROCESSING_FINISHED_SUCCESSFULLY} on successful processing
52 * or {@link ProcessingState#PROCESSING_TERMINATED_EARLY} if processing fails
54 protected ProcessingState processingState = ProcessingState.PROCESSING_NOT_REQUIRED;
57 * Sub classes must provide a description of a processor
59 * @return description of processor
62 public abstract String getProcessorDescription();
66 * Sub classes must provide implementation to process Message
68 * @param processorContext incoming {@link ProcessorContext}
69 * @return outgoing {@link ProcessorContext}
71 public abstract P processMessage(P processorContext);
74 public ProcessorInfo getProcessorInfo() {
75 // by default the class of the Processor is assigned as Processor Name
76 final String processorClassName = getClass().getSimpleName();
77 return new GenericProcessorInfo(processorClassName, getProcessorDescription());
81 public P preProcessor(P processorContext) {
82 LOG.debug("Processing Started for Processor: {}", getProcessorInfo().getProcessorName());
83 // by default check to see if continue processing Flag is not false
84 final boolean okToContinue = processorContext.canProcessingContinue();
86 final String errorMessage =
87 format("Processor: %s. Processing Context flag okToContinue is false. Unable to proceed...",
88 getProcessorInfo().getProcessorName());
89 throw new MessageProcessingException(errorMessage, LOG, new IllegalStateException(errorMessage));
91 processingState = ProcessingState.PROCESSING_STARTED;
92 return processorContext;
96 public ProcessingState getProcessingState() {
97 return processingState;
101 public Optional<String> getProcessingMessage() {
102 return Optional.fromNullable(processingMessage);
106 public P postProcessor(P processorContext) {
107 // Default implementation updates the post processing flag if processing did not
108 // completed successfully
109 if (processingState != ProcessingState.PROCESSING_FINISHED_SUCCESSFULLY) {
110 LOG.debug("Processor: {}, Update Process Context State to stop Processing.",
111 getProcessorInfo().getProcessorName());
112 processorContext.setProcessingContinueFlag(false);
114 // attaches itself to message processor context
115 processorContext.getMessageProcessors().add(this);
116 LOG.debug("Processing Completed for Processor: {}", getProcessorInfo());
117 return processorContext;
122 public final P apply(@Nonnull P processorContext) {
123 final P preProcessedProcessorContext = preProcessor(processorContext);
124 final P processedProcessorContext = processMessage(preProcessedProcessorContext);
125 return postProcessor(processedProcessorContext);
130 * Helper method that updates processing state in case of early termination, logs the processing
131 * termination reason, updates Processor processing state as Terminated and sets it processing message
133 * @param terminatingMessage error Message
134 * @param processorContext message processor context
136 protected void setTerminatingProcessingMessage(final String terminatingMessage,
137 final P processorContext) {
139 final String message = processorContext.getMessage();
140 this.processingState = ProcessingState.PROCESSING_TERMINATED_EARLY;
141 this.processingMessage = terminatingMessage;
142 LOG.debug("Processor: {}, Early Terminating Message: {}, Incoming Message: {}",
143 getProcessorInfo().getProcessorName(), terminatingMessage, message);
147 * Helper method that updates Processing state and logs completion message
150 * @param processorPassingMessage Processor passing message
151 * @param processorContext message processor context
153 protected void setFinishedProcessingMessage(final String processorPassingMessage, P processorContext) {
154 final String message = processorContext.getMessage();
155 processingState = ProcessingState.PROCESSING_FINISHED_SUCCESSFULLY;
156 this.processingMessage = processorPassingMessage;
157 LOG.debug("Processor: {}, Successful Completion Message: {}, Incoming Message: {}",
158 getProcessorInfo().getProcessorName(), processorPassingMessage, message);