Line data    Source code

       1             : #region Copyright
       2             : // // -----------------------------------------------------------------------
       3             : // // <copyright company="Chinchilla Software Limited">
       4             : // //   Copyright Chinchilla Software Limited. All rights reserved.
       5             : // // </copyright>
       6             : // // -----------------------------------------------------------------------
       7             : #endregion
       8             : 
       9             : using System;
      10             : using Cqrs.Bus;
      11             : using EventStore.ClientAPI;
      12             : 
      13             : namespace Cqrs.EventStore.Bus
      14             : {
      15             :         /// <summary>
      16             :         /// Indicates the position in store where the stream has been read up to.
      17             :         /// </summary>
      18             :         public class EventStoreBasedLastEventProcessedStore : IStoreLastEventProcessed
      19           1 :         {
      20             :                 /// <summary>
      21             :                 /// The name of the event stream use to store the position/location information.
      22             :                 /// </summary>
      23             :                 public const string EventsProcessedStreamName = @"EventsProcessed";
      24             : 
      25             :                 /// <summary>
      26             :                 /// The name of the event type we use in the event stream to store the position/location information.
      27             :                 /// </summary>
      28             :                 public const string EventType = @"ProcessedEvent";
      29             : 
      30             :                 /// <summary>
      31             :                 /// The <see cref="IEventStoreConnection"/> used to read and write streams in the Greg Young Event Store.
      32             :                 /// </summary>
      33             :                 protected IEventStoreConnection EventStoreConnection { get; private set; }
      34             : 
      35             :                 /// <summary>
      36             :                 /// Instantiates a new instance of <see cref="EventStoreBasedLastEventProcessedStore"/>.
      37             :                 /// </summary>
      38             :                 /// <param name="eventStoreConnection">The <see cref="IEventStoreConnection"/> used to read streams.</param>
      39           1 :                 public EventStoreBasedLastEventProcessedStore(IEventStoreConnection eventStoreConnection)
      40             :                 {
      41             :                         if (eventStoreConnection == null)
      42             :                         {
      43             :                                 throw new ArgumentNullException("eventStoreConnection");
      44             :                         }
      45             : 
      46             :                         EventStoreConnection = eventStoreConnection;
      47             :                 }
      48             : 
      49             :                 /// <summary>
      50             :                 /// The location within the store where the stream has been read up to.
      51             :                 /// </summary>
      52             :                 public string EventLocation
      53             :                 {
      54             :                         get
      55             :                         {
      56             :                                 StreamEventsSlice slice = EventStoreConnection.ReadStreamEventsBackwardAsync(EventsProcessedStreamName, StreamPosition.End, 1, false).Result;
      57             :                                 if (slice.Events.Length > 0)
      58             :                                 {
      59             :                                         return EventStoreUtilities.ByteArrayToString(slice.Events[0].Event.Data);
      60             :                                 }
      61             : 
      62             :                                 return string.Empty;
      63             :                         }
      64             :                         set
      65             :                         {
      66             :                                 var eventData = new EventData(Guid.NewGuid(), EventType, false, EventStoreUtilities.StringToByteArray(value), null);
      67             :                                 EventStoreConnection.AppendToStreamAsync(EventsProcessedStreamName, ExpectedVersion.Any, eventData).RunSynchronously();
      68             :                         }
      69             :                 }
      70             :         }
      71             : }