/**
* 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
* with the License. You may obtain a copy of the License at
*
* 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.flink.streaming.connectors.nifi;
import org.apache.flink.configuration.Configuration;
import org.apache.flink.streaming.api.functions.sink.RichSinkFunction;
import org.apache.nifi.remote.Transaction;
import org.apache.nifi.remote.TransferDirection;
import org.apache.nifi.remote.client.SiteToSiteClient;
import org.apache.nifi.remote.client.SiteToSiteClientConfig;
/**
* A sink that delivers data to Apache NiFi using the NiFi Site-to-Site client. The sink requires
* a NiFiDataPacketBuilder which can create instances of NiFiDataPacket from the incoming data.
*/
public class NiFiSink<T> extends RichSinkFunction<T> {
private SiteToSiteClient client;
private SiteToSiteClientConfig clientConfig;
private NiFiDataPacketBuilder<T> builder;
/**
* Construct a new NiFiSink with the given client config and NiFiDataPacketBuilder.
*
* @param clientConfig the configuration for building a NiFi SiteToSiteClient
* @param builder a builder to produce NiFiDataPackets from incoming data
*/
public NiFiSink(SiteToSiteClientConfig clientConfig, NiFiDataPacketBuilder<T> builder) {
this.clientConfig = clientConfig;
this.builder = builder;
}
@Override
public void open(Configuration parameters) throws Exception {
super.open(parameters);
this.client = new SiteToSiteClient.Builder().fromConfig(clientConfig).build();
}
@Override
public void invoke(T value) throws Exception {
final NiFiDataPacket niFiDataPacket = builder.createNiFiDataPacket(value, getRuntimeContext());
final Transaction transaction = client.createTransaction(TransferDirection.SEND);
if (transaction == null) {
throw new IllegalStateException("Unable to create a NiFi Transaction to send data");
}
transaction.send(niFiDataPacket.getContent(), niFiDataPacket.getAttributes());
transaction.confirm();
transaction.complete();
}
@Override
public void close() throws Exception {
super.close();
client.close();
}
}