/*
 * 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.kafka.test.base;

import org.apache.flink.api.common.restartstrategy.RestartStrategies;
import org.apache.flink.api.java.utils.ParameterTool;
import org.apache.flink.streaming.api.TimeCharacteristic;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;

/**
 * The util class for kafka example.
 */
public class KafkaExampleUtil {

	public static StreamExecutionEnvironment prepareExecutionEnv(ParameterTool parameterTool)
		throws Exception {

		if (parameterTool.getNumberOfParameters() < 5) {
			System.out.println("Missing parameters!\n" +
				"Usage: Kafka --input-topic <topic> --output-topic <topic> " +
				"--bootstrap.servers <kafka brokers> " +
				"--group.id <some id>");
			throw new Exception("Missing parameters!\n" +
				"Usage: Kafka --input-topic <topic> --output-topic <topic> " +
				"--bootstrap.servers <kafka brokers> " +
				"--group.id <some id>");
		}

		StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
				env.getConfig().setRestartStrategy(RestartStrategies.fixedDelayRestart(4, 10000));
		env.enableCheckpointing(5000); // create a checkpoint every 5 seconds
		env.getConfig().setGlobalJobParameters(parameterTool); // make parameters available in the web interface
		env.setStreamTimeCharacteristic(TimeCharacteristic.EventTime);

		return env;
	}

}
