/*
 * 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.elasticsearch.examples;

import org.apache.flink.api.common.functions.RuntimeContext;
import org.apache.flink.streaming.api.datastream.DataStreamSource;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.streaming.api.functions.source.SourceFunction;
import org.apache.flink.streaming.connectors.elasticsearch.ElasticsearchSink;
import org.apache.flink.streaming.connectors.elasticsearch.IndexRequestBuilder;
import org.elasticsearch.action.index.IndexRequest;
import org.elasticsearch.client.Requests;

import java.util.HashMap;
import java.util.Map;

/**
 * This example shows how to use the Elasticsearch Sink. Before running it you must ensure that
 * you have a cluster named "elasticsearch" running or change the cluster name in the config map.
 */
public class ElasticsearchExample {

	public static void main(String[] args) throws Exception {
		
		StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();

		DataStreamSource<String> source = env.addSource(new SourceFunction<String>() {
			private static final long serialVersionUID = 1L;

			private volatile boolean running = true;

			@Override
			public void run(SourceContext<String> ctx) throws Exception {
				for (int i = 0; i < 20 && running; i++) {
					ctx.collect("message #" + i);
				}
			}

			@Override
			public void cancel() {
				running = false;
			}
		});

		Map<String, String> config = new HashMap<>();
		// This instructs the sink to emit after every element, otherwise they would be buffered
		config.put(ElasticsearchSink.CONFIG_KEY_BULK_FLUSH_MAX_ACTIONS, "1");

		source.addSink(new ElasticsearchSink<>(config, new IndexRequestBuilder<String>() {
			@Override
			public IndexRequest createIndexRequest(String element, RuntimeContext ctx) {
				Map<String, Object> json = new HashMap<>();
				json.put("data", element);

				return Requests.indexRequest()
						.index("my-index")
						.type("my-type")
						.source(json);
			}
		}));


		env.execute("Elasticsearch Example");
	}
}