/*
* 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.neo4j.http;
import org.apache.streams.components.http.HttpPersistWriterConfiguration;
import org.apache.streams.components.http.persist.SimpleHTTPPostPersistWriter;
import org.apache.streams.config.ComponentConfigurator;
import org.apache.streams.config.StreamsConfigurator;
import org.apache.streams.core.StreamsDatum;
import org.apache.streams.graph.HttpGraphHelper;
import org.apache.streams.graph.QueryGraphHelper;
import org.apache.streams.neo4j.CypherQueryGraphHelper;
import org.apache.streams.jackson.StreamsJacksonMapper;
import org.apache.streams.neo4j.Neo4jConfiguration;
import org.apache.streams.neo4j.Neo4jPersistUtil;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.node.ArrayNode;
import com.fasterxml.jackson.databind.node.ObjectNode;
import org.apache.http.HttpEntity;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.util.EntityUtils;
import org.javatuples.Pair;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.IOException;
import java.util.List;
import java.util.Map;
import java.util.Objects;
import java.util.concurrent.locks.ReadWriteLock;
import java.util.concurrent.locks.ReentrantReadWriteLock;
/**
* Adds activityobjects as vertices and activities as edges to a graph database with
* an http rest endpoint (such as neo4j).
*/
public class Neo4jHttpPersistWriter extends SimpleHTTPPostPersistWriter {
public static final String STREAMS_ID = Neo4jHttpPersistWriter.class.getCanonicalName();
private static final Logger LOGGER = LoggerFactory.getLogger(Neo4jHttpPersistWriter.class);
private static final long MAX_WRITE_LATENCY = 1000;
private Neo4jConfiguration configuration;
private QueryGraphHelper queryGraphHelper;
private HttpGraphHelper httpGraphHelper;
private static ObjectMapper mapper;
protected final ReadWriteLock lock = new ReentrantReadWriteLock();
/**
* GraphHttpPersistWriter constructor - resolve GraphHttpConfiguration from JVM 'graph'.
*/
public Neo4jHttpPersistWriter() {
this(new ComponentConfigurator<>(Neo4jConfiguration.class).detectConfiguration(StreamsConfigurator.config.getConfig("neo4j")));
}
/**
* GraphHttpPersistWriter constructor - use supplied GraphHttpConfiguration.
* @param configuration GraphHttpConfiguration
*/
public Neo4jHttpPersistWriter(Neo4jConfiguration configuration) {
super((HttpPersistWriterConfiguration)StreamsJacksonMapper.getInstance().convertValue(configuration, HttpPersistWriterConfiguration.class).withHostname(configuration.getHosts().get(0)));
super.configuration.setResourcePath("/db/data/transaction/commit/");
this.configuration = configuration;
}
@Override
protected ObjectNode preparePayload(StreamsDatum entry) throws Exception {
List<Pair<String, Map<String, Object>>> statements = Neo4jPersistUtil.prepareStatements(entry);
ObjectNode requestNode = mapper.createObjectNode();
ArrayNode statementsArray = mapper.createArrayNode();
for( Pair<String, Map<String, Object>> statement : statements ) {
statementsArray.add(httpGraphHelper.writeData(statement));
}
requestNode.put("statements", statementsArray);
return requestNode;
}
@Override
protected ObjectNode executePost(HttpPost httpPost) {
Objects.requireNonNull(httpPost);
ObjectNode result = null;
CloseableHttpResponse response = null;
String entityString = null;
try {
response = httpclient.execute(httpPost);
HttpEntity entity = response.getEntity();
if (response.getStatusLine().getStatusCode() == 200 || response.getStatusLine().getStatusCode() == 201 && entity != null) {
entityString = EntityUtils.toString(entity);
result = mapper.readValue(entityString, ObjectNode.class);
}
LOGGER.debug("Writer response:\n{}\n{}\n{}", httpPost.toString(), response.getStatusLine().getStatusCode(), entityString);
if ( result == null
|| (
result.get("errors") != null
&& result.get("errors").isArray()
&& result.get("errors").iterator().hasNext()
)
) {
LOGGER.error("Write Error: " + result.get("errors"));
} else {
LOGGER.debug("Write Success");
}
} catch (IOException ex) {
LOGGER.error("IO error:\n{}\n{}\n{}", httpPost.toString(), response, ex.getMessage());
} catch (Exception ex) {
LOGGER.error("Write Exception:\n{}\n{}\n{}", httpPost.toString(), response, ex.getMessage());
} finally {
try {
if ( response != null) {
response.close();
}
} catch (IOException ignored) {
LOGGER.trace("ignored IOException", ignored);
}
}
return result;
}
@Override
public void prepare(Object configurationObject) {
super.prepare(null);
mapper = StreamsJacksonMapper.getInstance();
queryGraphHelper = new CypherQueryGraphHelper();
httpGraphHelper = new Neo4jHttpGraphHelper();
Objects.requireNonNull(queryGraphHelper);
Objects.requireNonNull(httpGraphHelper);
}
@Override
public void cleanUp() {
LOGGER.info("exiting");
}
}