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* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
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*
*    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
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package org.apache.cassandra.locator;

import java.net.InetAddress;
import java.util.*;
import java.util.Set;

import org.apache.cassandra.db.Table;

import org.apache.commons.lang.StringUtils;
import org.junit.Test;

import org.apache.cassandra.SchemaLoader;
import org.apache.cassandra.config.ConfigurationException;
import org.apache.cassandra.dht.BigIntegerToken;
import org.apache.cassandra.dht.Token;

public class ReplicationStrategyEndpointCacheTest extends SchemaLoader
{
    private TokenMetadata tmd;
    private Token searchToken;
    private AbstractReplicationStrategy strategy;

    public void setup(Class stratClass, Map<String, String> strategyOptions) throws Exception
    {
        tmd = new TokenMetadata();
        searchToken = new BigIntegerToken(String.valueOf(15));

        strategy = getStrategyWithNewTokenMetadata(Table.open("Keyspace3").getReplicationStrategy(), tmd);

        tmd.updateNormalToken(new BigIntegerToken(String.valueOf(10)), InetAddress.getByName("127.0.0.1"));
        tmd.updateNormalToken(new BigIntegerToken(String.valueOf(20)), InetAddress.getByName("127.0.0.2"));
        tmd.updateNormalToken(new BigIntegerToken(String.valueOf(30)), InetAddress.getByName("127.0.0.3"));
        tmd.updateNormalToken(new BigIntegerToken(String.valueOf(40)), InetAddress.getByName("127.0.0.4"));
        //tmd.updateNormalToken(new BigIntegerToken(String.valueOf(50)), InetAddress.getByName("127.0.0.5"));
        tmd.updateNormalToken(new BigIntegerToken(String.valueOf(60)), InetAddress.getByName("127.0.0.6"));
        tmd.updateNormalToken(new BigIntegerToken(String.valueOf(70)), InetAddress.getByName("127.0.0.7"));
        tmd.updateNormalToken(new BigIntegerToken(String.valueOf(80)), InetAddress.getByName("127.0.0.8"));
    }

    @Test
    public void testEndpointsWereCached() throws Exception
    {
        runEndpointsWereCachedTest(FakeSimpleStrategy.class, null);
        runEndpointsWereCachedTest(FakeOldNetworkTopologyStrategy.class, null);
        runEndpointsWereCachedTest(FakeNetworkTopologyStrategy.class, new HashMap<String, String>());
    }

    public void runEndpointsWereCachedTest(Class stratClass, Map<String, String> configOptions) throws Exception
    {
        setup(stratClass, configOptions);
        assert strategy.getNaturalEndpoints(searchToken).equals(strategy.getNaturalEndpoints(searchToken));
    }

    @Test
    public void testCacheRespectsTokenChanges() throws Exception
    {
        runCacheRespectsTokenChangesTest(SimpleStrategy.class, null);
        runCacheRespectsTokenChangesTest(OldNetworkTopologyStrategy.class, null);
        runCacheRespectsTokenChangesTest(NetworkTopologyStrategy.class, new HashMap<String, String>());
    }

    public void runCacheRespectsTokenChangesTest(Class stratClass, Map<String, String> configOptions) throws Exception
    {
        setup(stratClass, configOptions);
        Set<InetAddress> initial;
        Set<InetAddress> endpoints;

        endpoints = strategy.getNaturalEndpoints(searchToken).keySet();
        assert endpoints.size() == 5 : StringUtils.join(endpoints, ",");

        // test token addition, in DC2 before existing token
        initial = strategy.getNaturalEndpoints(searchToken).keySet();
        tmd.updateNormalToken(new BigIntegerToken(String.valueOf(35)), InetAddress.getByName("127.0.0.5"));
        endpoints = strategy.getNaturalEndpoints(searchToken).keySet();
        assert endpoints.size() == 5 : StringUtils.join(endpoints, ",");
        assert !endpoints.equals(initial);

        // test token removal, newly created token
        initial = strategy.getNaturalEndpoints(searchToken).keySet();
        tmd.removeEndpoint(InetAddress.getByName("127.0.0.5"));
        endpoints = strategy.getNaturalEndpoints(searchToken).keySet();
        assert endpoints.size() == 5 : StringUtils.join(endpoints, ",");
        assert !endpoints.contains(InetAddress.getByName("127.0.0.5"));
        assert !endpoints.equals(initial);

        // test token change
        initial = strategy.getNaturalEndpoints(searchToken).keySet();
        //move .8 after search token but before other DC3
        tmd.updateNormalToken(new BigIntegerToken(String.valueOf(25)), InetAddress.getByName("127.0.0.8"));
        endpoints = strategy.getNaturalEndpoints(searchToken).keySet();
        assert endpoints.size() == 5 : StringUtils.join(endpoints, ",");
        assert !endpoints.equals(initial);
    }

    protected static class FakeSimpleStrategy extends SimpleStrategy
    {
        private boolean called = false;

        public FakeSimpleStrategy(String table, TokenMetadata tokenMetadata, IEndpointSnitch snitch, Map<String, String> configOptions)
        {
            super(table, tokenMetadata, snitch, configOptions);
        }

        public Map<InetAddress, Integer> calculateNaturalEndpoints(Token token, TokenMetadata metadata)
        {
            assert !called : "calculateNaturalEndpoints was already called, result should have been cached";
            called = true;
            return super.calculateNaturalEndpoints(token, metadata);
        }
    }

    protected static class FakeOldNetworkTopologyStrategy extends OldNetworkTopologyStrategy
    {
        private boolean called = false;

        public FakeOldNetworkTopologyStrategy(String table, TokenMetadata tokenMetadata, IEndpointSnitch snitch, Map<String, String> configOptions)
        {
            super(table, tokenMetadata, snitch, configOptions);
        }

        public Map<InetAddress, Integer> calculateNaturalEndpoints(Token token, TokenMetadata metadata)
        {
            assert !called : "calculateNaturalEndpoints was already called, result should have been cached";
            called = true;
            return super.calculateNaturalEndpoints(token, metadata);
        }
    }

    protected static class FakeNetworkTopologyStrategy extends NetworkTopologyStrategy
    {
        private boolean called = false;

        public FakeNetworkTopologyStrategy(String table, TokenMetadata tokenMetadata, IEndpointSnitch snitch, Map<String, String> configOptions) throws ConfigurationException
        {
            super(table, tokenMetadata, snitch, configOptions);
        }

        public Map<InetAddress, Integer> calculateNaturalEndpoints(Token token, TokenMetadata metadata)
        {
            assert !called : "calculateNaturalEndpoints was already called, result should have been cached";
            called = true;
            return super.calculateNaturalEndpoints(token, metadata);
        }
    }

    private AbstractReplicationStrategy getStrategyWithNewTokenMetadata(AbstractReplicationStrategy strategy, TokenMetadata newTmd) throws ConfigurationException
    {
        return AbstractReplicationStrategy.createReplicationStrategy(
                strategy.table,
                strategy.getClass().getName(),
                newTmd,
                strategy.snitch,
                strategy.configOptions);
    }

}