io.druid.data.input.impl.prefetch.RetryingInputStreamTest.java Source code

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Here is the source code for io.druid.data.input.impl.prefetch.RetryingInputStreamTest.java

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/*
 * Licensed to Metamarkets Group Inc. (Metamarkets) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. Metamarkets 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 io.druid.data.input.impl.prefetch;

import com.google.common.base.Preconditions;
import org.apache.commons.io.FileUtils;
import org.junit.After;
import org.junit.Assert;
import org.junit.Before;
import org.junit.Rule;
import org.junit.Test;
import org.junit.rules.TemporaryFolder;

import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.SocketException;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;

public class RetryingInputStreamTest {
    private static final int MAX_RETRY = 5;
    private static final int MAX_ERROR = 4;

    @Rule
    public TemporaryFolder temporaryFolder = new TemporaryFolder();

    private File testFile;
    private DataInputStream inputStream;

    @Before
    public void setup() throws IOException {
        testFile = temporaryFolder.newFile();

        try (FileOutputStream fis = new FileOutputStream(testFile);
                GZIPOutputStream gis = new GZIPOutputStream(fis);
                DataOutputStream dis = new DataOutputStream(gis)) {
            for (int i = 0; i < 10000; i++) {
                dis.writeInt(i);
            }
        }

        throwError = false;

        final InputStream retryingInputStream = new RetryingInputStream<>(testFile, new ObjectOpenFunction<File>() {
            @Override
            public InputStream open(File object) throws IOException {
                return new TestInputStream(new FileInputStream(object));
            }

            @Override
            public InputStream open(File object, long start) throws IOException {
                final FileInputStream fis = new FileInputStream(object);
                Preconditions.checkState(fis.skip(start) == start);
                return new TestInputStream(fis);
            }
        }, e -> e instanceof IOException, MAX_RETRY);

        inputStream = new DataInputStream(new GZIPInputStream(retryingInputStream));

        throwError = true;
    }

    @After
    public void teardown() throws IOException {
        inputStream.close();
        FileUtils.forceDelete(testFile);
    }

    @Test
    public void testReadRetry() throws IOException {
        for (int i = 0; i < 10000; i++) {
            Assert.assertEquals(i, inputStream.readInt());
        }
    }

    private boolean throwError = true;
    private int errorCount = 0;

    private class TestInputStream extends InputStream {
        private final InputStream delegate;

        TestInputStream(InputStream delegate) {
            this.delegate = delegate;
        }

        @Override
        public int read() throws IOException {
            return delegate.read();
        }

        @Override
        public int read(byte b[], int off, int len) throws IOException {
            if (throwError) {
                throwError = false;
                errorCount++;
                if (errorCount % 2 == 0) {
                    throw new IOException("test retry");
                } else {
                    delegate.close();
                    throw new SocketException("Test Connection reset");
                }
            } else {
                throwError = errorCount < MAX_ERROR;
                return delegate.read(b, off, len);
            }
        }
    }
}