TestingRedisDatabaseProvider.cs

using NUnit.Framework;
using StackExchange.Redis;
using StackExchange.Redis.KeyspaceIsolation;
using System.Diagnostics;

namespace Medallion.Threading.Tests.Redis;

public abstract class TestingRedisDatabaseProvider
{
    protected TestingRedisDatabaseProvider(IEnumerable<IDatabase> databases)
    {
        this.Databases = databases.ToArray();
    }

    protected TestingRedisDatabaseProvider(int count)
        : this(Enumerable.Range(0, count).Select(i => RedisServer.GetDefaultServer(i).Multiplexer.GetDatabase()))
    {
    }

    // publicly settable so that callers can alter the dbs in use
    public IReadOnlyList<IDatabase> Databases { get; set; }

    public virtual string CrossProcessLockTypeSuffix => this.Databases.Count.ToString();
}

public sealed class TestingRedisSingleDatabaseProvider : TestingRedisDatabaseProvider
{
    public TestingRedisSingleDatabaseProvider() : base(count: 1) { }
}

public sealed class TestingRedisWithKeyPrefixSingleDatabaseProvider : TestingRedisDatabaseProvider
{
    public TestingRedisWithKeyPrefixSingleDatabaseProvider()
        : base(new[] { RedisServer.GetDefaultServer(0).Multiplexer.GetDatabase().WithKeyPrefix("distributed_locks:") }) { }

    public override string CrossProcessLockTypeSuffix => "1WithPrefix";
}

public sealed class TestingRedis3DatabaseProvider : TestingRedisDatabaseProvider
{
    public TestingRedis3DatabaseProvider() : base(count: 3) { }
}

public sealed class TestingRedis2x1DatabaseProvider : TestingRedisDatabaseProvider
{
    private static readonly IDatabase DeadDatabase;

    static TestingRedis2x1DatabaseProvider()
    {
        var server = new RedisServer(allowAdmin: true);
        DeadDatabase = server.Multiplexer.GetDatabase();
        server.Multiplexer.GetServer($"localhost:{server.Port}").Shutdown(ShutdownMode.Never);
        server.Dispose();
    }

    public TestingRedis2x1DatabaseProvider()
        : base(Enumerable.Range(0, 2).Select(i => RedisServer.GetDefaultServer(i).Multiplexer.GetDatabase()).Append(DeadDatabase))
    {
    }

    public override string CrossProcessLockTypeSuffix => "2x1";
}