/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.streams.facebook.processor;
import org.apache.streams.core.StreamsDatum;
import org.apache.streams.core.StreamsProcessor;
import org.apache.streams.exceptions.ActivitySerializerException;
import org.apache.streams.facebook.Page;
import org.apache.streams.facebook.Post;
import org.apache.streams.facebook.api.FacebookPageActivitySerializer;
import org.apache.streams.facebook.api.FacebookPostActivitySerializer;
import org.apache.streams.facebook.provider.FacebookEventClassifier;
import org.apache.streams.jackson.StreamsJacksonMapper;
import org.apache.streams.pojo.json.Activity;
import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.node.ObjectNode;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Queue;
import java.util.stream.Collectors;
import java.util.stream.Stream;
/**
* FacebookTypeConverter converts facebook data to activity streams types.
*/
public class FacebookTypeConverter implements StreamsProcessor {
public static final String STREAMS_ID = "FacebookTypeConverter";
private static final Logger LOGGER = LoggerFactory.getLogger(FacebookTypeConverter.class);
private ObjectMapper mapper;
private Queue<StreamsDatum> inQueue;
private Queue<StreamsDatum> outQueue;
private Class inClass;
private Class outClass;
private FacebookPostActivitySerializer facebookPostActivitySerializer;
private FacebookPageActivitySerializer facebookPageActivitySerializer;
private int count = 0;
public static final String TERMINATE = "TERMINATE";
public FacebookTypeConverter(Class inClass, Class outClass) {
this.inClass = inClass;
this.outClass = outClass;
}
public Queue<StreamsDatum> getProcessorOutputQueue() {
return outQueue;
}
public void setProcessorInputQueue(Queue<StreamsDatum> inputQueue) {
inQueue = inputQueue;
}
/**
* convert.
* @param event event
* @param inClass inClass
* @param outClass outClass
* @return Object
* @throws ActivitySerializerException ActivitySerializerException
* @throws JsonProcessingException JsonProcessingException
*/
public Object convert(ObjectNode event, Class inClass, Class outClass) throws ActivitySerializerException, JsonProcessingException {
Object result = null;
if ( outClass.equals( Activity.class )) {
LOGGER.debug("ACTIVITY");
if (inClass.equals(Post.class)) {
LOGGER.debug("POST");
result = facebookPostActivitySerializer.deserialize(mapper.convertValue(event, Post.class));
} else if (inClass.equals(Page.class)) {
LOGGER.debug("PAGE");
result = facebookPageActivitySerializer.deserialize(mapper.convertValue(event, Page.class));
}
} else if ( outClass.equals( Post.class )) {
LOGGER.debug("POST");
result = mapper.convertValue(event, Post.class);
} else if ( outClass.equals(Page.class)) {
LOGGER.debug("PAGE");
result = mapper.convertValue(event, Page.class);
} else if ( outClass.equals( ObjectNode.class )) {
LOGGER.debug("OBJECTNODE");
result = mapper.convertValue(event, ObjectNode.class);
}
// no supported conversion were applied
if ( result != null ) {
count ++;
return result;
}
LOGGER.debug("CONVERT FAILED");
return null;
}
// TODO: use standard validation
public boolean validate(Object document, Class klass) {
return true;
}
// TODO: replace with standard validation
public boolean isValidJSON(final String json) {
boolean valid = false;
try {
final JsonParser parser = new ObjectMapper().getJsonFactory()
.createJsonParser(json);
while (parser.nextToken() != null) {
}
valid = true;
} catch (IOException ioe) {
LOGGER.warn("validate: {}", ioe);
}
return valid;
}
@Override
public String getId() {
return STREAMS_ID;
}
@Override
public List<StreamsDatum> process(StreamsDatum entry) {
StreamsDatum result = null;
try {
Object item = entry.getDocument();
ObjectNode node;
LOGGER.debug("{} processing {}", STREAMS_ID, item.getClass());
if ( item instanceof String ) {
// if the target is string, just pass-through
if ( String.class.equals(outClass)) {
result = entry;
} else {
// first check for valid json
node = (ObjectNode)mapper.readTree((String)item);
// since data is coming from outside provider, we don't know what type the events are
// for now we'll assume post
Class inClass = FacebookEventClassifier.detectClass((String) item);
Object out = convert(node, inClass, outClass);
if ( out != null && validate(out, outClass)) {
result = new StreamsDatum(out);
}
}
} else if ( item instanceof ObjectNode) {
// first check for valid json
node = mapper.valueToTree(item);
Class inClass = FacebookEventClassifier.detectClass(mapper.writeValueAsString(item));
Object out = convert(node, inClass, outClass);
if ( out != null && validate(out, outClass)) {
result = new StreamsDatum(out);
}
} else if (item instanceof Post || item instanceof Page) {
Object out = convert(mapper.convertValue(item, ObjectNode.class), inClass, outClass);
if ( out != null && validate(out, outClass)) {
result = new StreamsDatum(out);
}
}
} catch (Exception ex) {
LOGGER.error("Exception switching types : {}", ex);
if (ex instanceof InterruptedException) {
Thread.currentThread().interrupt();
}
}
if ( result != null ) {
return Stream.of(result).collect(Collectors.toList());
} else {
return new ArrayList<>();
}
}
@Override
public void prepare(Object configurationObject) {
mapper = StreamsJacksonMapper.getInstance();
facebookPageActivitySerializer = new FacebookPageActivitySerializer();
facebookPostActivitySerializer = new FacebookPostActivitySerializer();
}
@Override
public void cleanUp() {}
}