/*
 * 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.test.accumulators;

import org.apache.flink.api.common.JobExecutionResult;
import org.apache.flink.api.common.accumulators.Accumulator;
import org.apache.flink.api.common.accumulators.DoubleCounter;
import org.apache.flink.api.common.accumulators.LongCounter;
import org.apache.flink.api.common.functions.RichMapFunction;
import org.apache.flink.api.java.ExecutionEnvironment;
import org.apache.flink.api.java.io.DiscardingOutputFormat;
import org.apache.flink.configuration.Configuration;
import org.apache.flink.configuration.TaskManagerOptions;
import org.apache.flink.runtime.client.JobExecutionException;
import org.apache.flink.runtime.testutils.MiniClusterResourceConfiguration;
import org.apache.flink.test.util.MiniClusterWithClientResource;
import org.apache.flink.util.ExceptionUtils;
import org.apache.flink.util.TestLogger;

import org.junit.ClassRule;
import org.junit.Test;

import static org.junit.Assert.assertTrue;
import static org.junit.Assert.fail;

/**
 * Tests cases where accumulators:
 *  a) throw errors during runtime
 *  b) are not compatible with existing accumulator.
 */
public class AccumulatorErrorITCase extends TestLogger {
	private static final String FAULTY_CLONE_ACCUMULATOR = "faulty-clone";
	private static final String FAULTY_MERGE_ACCUMULATOR = "faulty-merge";
	private static final String INCOMPATIBLE_ACCUMULATORS_NAME = "incompatible-accumulators";

	@ClassRule
	public static final MiniClusterWithClientResource MINI_CLUSTER_RESOURCE = new MiniClusterWithClientResource(
		new MiniClusterResourceConfiguration.Builder()
			.setNumberTaskManagers(2)
			.setNumberSlotsPerTaskManager(3)
			.build());

	public static Configuration getConfiguration() {
		Configuration config = new Configuration();
		config.setString(TaskManagerOptions.LEGACY_MANAGED_MEMORY_SIZE, "12m");
		return config;
	}

	@Test
	public void testFaultyAccumulator() throws Exception {
		ExecutionEnvironment env = ExecutionEnvironment.getExecutionEnvironment();

		// Test Exception forwarding with faulty Accumulator implementation
		env.generateSequence(0, 10000)
			.map(new FaultyAccumulatorUsingMapper())
			.output(new DiscardingOutputFormat<>());

		assertAccumulatorsShouldFail(env.execute());
	}

	@Test
	public void testInvalidTypeAccumulator() throws Exception {
		ExecutionEnvironment env = ExecutionEnvironment.getExecutionEnvironment();

		// Test Exception forwarding with faulty Accumulator implementation
		env.generateSequence(0, 10000)
			.map(new IncompatibleAccumulatorTypesMapper())
			.map(new IncompatibleAccumulatorTypesMapper2())
			.output(new DiscardingOutputFormat<>());

		try {
			env.execute();
			fail("Should have failed.");
		} catch (JobExecutionException e) {
			assertTrue("Root cause should be:",
					e.getCause() instanceof Exception);
			assertTrue("Root cause should be:",
					e.getCause().getCause() instanceof UnsupportedOperationException);
		}
	}

	@Test
	public void testFaultyMergeAccumulator() throws Exception {
		ExecutionEnvironment env = ExecutionEnvironment.getExecutionEnvironment();

		// Test Exception forwarding with faulty Accumulator implementation
		env.generateSequence(0, 10000)
			.map(new FaultyMergeAccumulatorUsingMapper())
			.output(new DiscardingOutputFormat<>());

		assertAccumulatorsShouldFail(env.execute());
	}

	/* testFaultyAccumulator */

	private static class FaultyAccumulatorUsingMapper extends RichMapFunction<Long, Long> {
		private static final long serialVersionUID = 42;

		@Override
		public void open(Configuration parameters) throws Exception {
			getRuntimeContext().addAccumulator(FAULTY_CLONE_ACCUMULATOR, new FaultyCloneAccumulator());
		}

		@Override
		public Long map(Long value) throws Exception {
			return -1L;
		}
	}

	private static class FaultyCloneAccumulator extends LongCounter {
		private static final long serialVersionUID = 42;

		@Override
		public LongCounter clone() {
			throw new CustomException();
		}
	}

	/* testInvalidTypeAccumulator */

	private static class IncompatibleAccumulatorTypesMapper extends RichMapFunction<Long, Long> {
		private static final long serialVersionUID = 42;

		@Override
		public void open(Configuration parameters) throws Exception {
			getRuntimeContext().addAccumulator(INCOMPATIBLE_ACCUMULATORS_NAME, new LongCounter());
		}

		@Override
		public Long map(Long value) throws Exception {
			return -1L;
		}
	}

	private static class IncompatibleAccumulatorTypesMapper2 extends RichMapFunction<Long, Long> {
		private static final long serialVersionUID = 42;

		@Override
		public void open(Configuration parameters) throws Exception {
			getRuntimeContext().addAccumulator(INCOMPATIBLE_ACCUMULATORS_NAME, new DoubleCounter());
		}

		@Override
		public Long map(Long value) throws Exception {
			return -1L;
		}
	}

	/** */

	private static class FaultyMergeAccumulatorUsingMapper extends RichMapFunction<Long, Long> {
		private static final long serialVersionUID = 42;

		@Override
		public void open(Configuration parameters) throws Exception {
			getRuntimeContext().addAccumulator(FAULTY_MERGE_ACCUMULATOR, new FaultyMergeAccumulator());
		}

		@Override
		public Long map(Long value) throws Exception {
			return -1L;
		}
	}

	private static class FaultyMergeAccumulator extends LongCounter {
		private static final long serialVersionUID = 42;

		@Override
		public void merge(Accumulator<Long, Long> other) {
			throw new CustomException();
		}

		@Override
		public LongCounter clone() {
			return new FaultyMergeAccumulator();
		}
	}

	private static class CustomException extends RuntimeException {
		private static final long serialVersionUID = 42;
	}

	private static void assertAccumulatorsShouldFail(JobExecutionResult result) {
		try {
			result.getAllAccumulatorResults();
			fail("Should have failed");
		}
		catch (Exception ex) {
			assertTrue(ExceptionUtils.findThrowable(ex, CustomException.class).isPresent());
		}
	}
}

@@ -1580,53 +1580,8 @@
 ce;%0A
-import org.apache.flink.util.ExceptionUtils;%0A
 impo
@@ -1670,16 +1670,82 @@
 .Test;%0A%0A
+import static org.apache.flink.util.ExceptionUtils.findThrowable;%0A
 import s
@@ -3576,152 +3576,24 @@
 rue(
-%22Root cause should be:%22,%0A%09%09%09%09%09e.getCause() instanceof Exception);%0A%09%09%09assertTrue(%22Root cause should be:%22,%0A%09%09%09%09%09e.getCause().getCause() instanceof
+findThrowable(e,
  Uns
@@ -3618,16 +3618,35 @@
 xception
+.class).isPresent()
 );%0A%09%09%7D%0A%09
@@ -6563,31 +6563,16 @@
 ertTrue(
-ExceptionUtils.
 findThro

Enable AccumulatorErrorITCase to pass with NG scheduler