Line data    Source code

       1             : #region Copyright
       2             : // // -----------------------------------------------------------------------
       3             : // // <copyright company="cdmdotnet Limited">
       4             : // //   Copyright cdmdotnet Limited. All rights reserved.
       5             : // // </copyright>
       6             : // // -----------------------------------------------------------------------
       7             : #endregion
       8             : 
       9             : using System;
      10             : using System.Linq;
      11             : using Cqrs.Domain;
      12             : 
      13             : namespace Cqrs.Snapshots
      14             : {
      15             :         /// <summary>
      16             :         /// An <see cref="ISnapshotStrategy{TAuthenticationToken}"/> that takes a snapshot every 15 versions
      17             :         /// </summary>
      18             :         /// <typeparam name="TAuthenticationToken"></typeparam>
      19             :         public class DefaultSnapshotStrategy<TAuthenticationToken> : ISnapshotStrategy<TAuthenticationToken>
      20           1 :         {
      21             :                 private const int SnapshotInterval = 15;
      22             : 
      23           0 :                 public bool IsSnapshotable(Type aggregateType)
      24             :                 {
      25             :                         if (aggregateType.BaseType == null)
      26             :                                 return false;
      27             :                         if (aggregateType.BaseType.IsGenericType && aggregateType.BaseType.GetGenericTypeDefinition() == typeof(SnapshotAggregateRoot<,>))
      28             :                                 return true;
      29             :                         return IsSnapshotable(aggregateType.BaseType);
      30             :                 }
      31             : 
      32           0 :                 public bool ShouldMakeSnapShot(IAggregateRoot<TAuthenticationToken> aggregate)
      33             :                 {
      34             :                         if (!IsSnapshotable(aggregate.GetType()))
      35             :                                 return false;
      36             :                         int i = aggregate.Version;
      37             : 
      38             :                         int limit = aggregate.GetUncommittedChanges().Count();
      39             :                         for (int j = 0; j < limit; j++)
      40             :                                 if (++i % SnapshotInterval == 0 && i != 0)
      41             :                                         return true;
      42             :                         return false;
      43             :                 }
      44             :         }
      45             : }