/*
 * 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.contrib.streaming;

import org.apache.flink.configuration.Configuration;
import org.apache.flink.runtime.minicluster.LocalFlinkMiniCluster;
import org.apache.flink.streaming.api.datastream.DataStream;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.streaming.util.TestStreamEnvironment;
import org.apache.flink.util.TestLogger;

import org.junit.Test;

import java.util.Iterator;

import static org.junit.Assert.*;

/**
 * This test verifies the behavior of DataStreamUtils.collect.
 */
public class CollectITCase extends TestLogger {

	@Test
	public void testCollect() throws Exception {
		final LocalFlinkMiniCluster cluster = new LocalFlinkMiniCluster(new Configuration(), false);
		try {
			cluster.start();

			TestStreamEnvironment.setAsContext(cluster, 1);

			final StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
	
			final long N = 10;
			DataStream<Long> stream = env.generateSequence(1, N);
	
			long i = 1;
			for (Iterator<Long> it = DataStreamUtils.collect(stream); it.hasNext(); ) {
				long x = it.next();
				assertEquals("received wrong element", i, x);
				i++;
			}
			
			assertEquals("received wrong number of elements", N + 1, i);
		}
		finally {
			TestStreamEnvironment.unsetAsContext();
			cluster.stop();
		}
	}
}