src/Lucene.Net.Replicator/IAsyncReplicator.cs

using System.IO;
using System.Threading;
using System.Threading.Tasks;

#nullable enable

namespace Lucene.Net.Replicator
{
    /// <summary>
    /// Async extension of <see cref="IReplicator"/> for non-blocking replication operations.
    /// Implementations provide both synchronous (inherited from <see cref="IReplicator"/>)
    /// and asynchronous methods.
    /// </summary>
    public interface IAsyncReplicator : IReplicator
    {
        /// <summary>
        /// Check whether the given version is up-to-date and returns a
        /// <see cref="SessionToken"/> which can be used for fetching the revision files.
        /// </summary>
        /// <param name="currentVersion">Current version of the index.</param>
        /// <param name="cancellationToken">Cancellation token.</param>
        /// <returns>A <see cref="SessionToken"/> if an update exists; otherwise, <c>null</c>.</returns>
        Task<SessionToken?> CheckForUpdateAsync(string? currentVersion, CancellationToken cancellationToken = default);

        /// <summary>
        /// Returns a stream for the requested file and source.
        /// </summary>
        Task<Stream> ObtainFileAsync(string sessionId, string source, string fileName, CancellationToken cancellationToken = default);

        /// <summary>
        /// Notify that the specified session is no longer needed.
        /// </summary>
        Task ReleaseAsync(string sessionId, CancellationToken cancellationToken = default);

        /// <summary>
        /// Publish a new <see cref="IRevision"/> for consumption by clients asynchronously.
        /// See <see cref="IReplicator.Publish(IRevision)"/> for details.
        /// </summary>
        Task PublishAsync(IRevision revision, CancellationToken cancellationToken = default);
    }
}