IOrchestrationSession.cs

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#nullable enable
namespace DurableTask.Core
{
    using System.Collections.Generic;
    using System.Threading.Tasks;

    /// <summary>
    /// Interface allowing providers to implement extended sessions (aka "sticky sessions").
    /// </summary>
    public interface IOrchestrationSession
    {
        /// <summary>
        /// When implemented, fetches a new batch of messages for a particular work item.
        /// </summary>
        /// <remarks>
        /// Implementors of this method should feel free to block until new messages are available,
        /// or until an internal wait period has expired. In either case, <c>null</c> can be returned
        /// and the dispatcher will shut down the session.
        /// </remarks>
        Task<IList<TaskMessage>?> FetchNewOrchestrationMessagesAsync(TaskOrchestrationWorkItem workItem);

        /// <summary>
        /// Ends the session.
        /// </summary>
        /// <returns>A task that completes when the session has been ended.</returns>
        Task EndSessionAsync();
    }
}