对分片操作符注释进行修改和完善,针对定时分片时间的补偿，防止提前创建表导致重启后内存中可能不会存在分片信息

samples/Sample.SqlServer/Shardings/TestYearShardingVirtualTableRoute.cs

@@ -26,6 +26,5 @@ namespace Sample.SqlServer.Shardings
         {
             return true;
         }
-
     }
 }

src/ShardingCore/Core/Collections/SafeReadAppendList.cs

@@ -16,7 +16,7 @@ namespace ShardingCore.Core.Collections
         {
         }
 
-        public IReadOnlyList<T> Data => _list;
+        public ImmutableList<T> Data => _list;
 
         public void Append(T value)
         {

src/ShardingCore/Jobs/Abstaractions/IJob.cs

@@ -7,7 +7,7 @@ namespace ShardingCore.Jobs.Abstaractions
     public interface IJob
     {
         string JobName { get; }
-        string[] GetCronExpressions();
+        string[] GetJobCronExpressions();
         Task ExecuteAsync();
         bool AppendJob();
     }

src/ShardingCore/Jobs/Impls/JobEntry.cs

@@ -15,6 +15,12 @@ namespace ShardingCore.Jobs.Impls
 */
     public sealed class JobEntry
     {
+        public JobEntry(IJob job)
+        {
+            JobInstance = job;
+            JobName = job.JobName;
+            JobCronExpressions = job.GetJobCronExpressions();
+        }
         /// <summary>
         /// 保证多线程只有一个清理操作
         /// </summary>
@@ -32,7 +38,7 @@ namespace ShardingCore.Jobs.Impls
         /// <summary>
         /// job实例
         /// </summary>
-        public IJob JobInstance { get; set; }
+        public IJob JobInstance { get; }
 
         /// <summary>
         /// 是否跳过如果正在运行
@@ -43,6 +49,10 @@ namespace ShardingCore.Jobs.Impls
         /// 下次运行时间
         /// </summary>
         public DateTime? NextUtcTime { get; set; }
+        /// <summary>
+        /// 任务的cron表达式
+        /// </summary>
+        public string[] JobCronExpressions { get; }
 
         /// <summary>
         /// 是否正在运行
@@ -69,7 +79,7 @@ namespace ShardingCore.Jobs.Impls
         /// </summary>
         public void CalcNextUtcTime()
         {
-            this.NextUtcTime= JobInstance.GetCronExpressions().Select(cron => new CronExpression(cron).GetTimeAfter(DateTime.UtcNow)).Min();
+            this.NextUtcTime= JobCronExpressions.Select(cron => new CronExpression(cron).GetTimeAfter(DateTime.UtcNow)).Min();
         }
     }
 }

src/ShardingCore/Jobs/JobEntryFactory.cs

@@ -17,11 +17,7 @@ namespace ShardingCore.Jobs
         public static JobEntry Create(IJob job)
         {
 
-            var jobEntry = new JobEntry()
+            var jobEntry = new JobEntry(job);
-            {
-                JobInstance = job,
-                JobName = job.JobName,
-            };
             jobEntry.CalcNextUtcTime();
             return jobEntry;
         }

src/ShardingCore/VirtualRoutes/Abstractions/AbstractShardingAutoCreateOperatorVirtualTableRoute.cs

@@ -22,12 +22,17 @@ using ShardingCore.TableCreator;
 
 namespace ShardingCore.VirtualRoutes.Abstractions
 {
+    /// <summary>
+    /// 分片字段追加
+    /// </summary>
+    /// <typeparam name="TEntity"></typeparam>
+    /// <typeparam name="TKey"></typeparam>
     [ExcludeFromCodeCoverage]
     public abstract class
         AbstractShardingAutoCreateOperatorVirtualTableRoute<TEntity, TKey> :
             AbstractShardingOperatorVirtualTableRoute<TEntity, TKey>, ITailAppendable, IJob where TEntity : class
     {
-        private static readonly object APPEND_LOCK = new object();
+        private  readonly object APPEND_LOCK = new object();
 
 
         private readonly SafeReadAppendList<string> _tails = new SafeReadAppendList<string>();
@@ -85,6 +90,17 @@ namespace ShardingCore.VirtualRoutes.Abstractions
         /// </summary>
         public virtual int IncrementMinutes => 10;
 
+        public string[] GetJobCronExpressions()
+        {
+            var cronExpressions = GetCronExpressions();
+            var compensateCronExpressions = GetCompensateCronExpressions();
+            return cronExpressions.Concat(compensateCronExpressions).Distinct().ToArray();
+        }
+        /// <summary>
+        /// 补偿cron防止提前创建后没有添加tail到内存中从而无法识别
+        /// </summary>
+        /// <returns></returns>
+        public abstract string[] GetCompensateCronExpressions();
         /// <summary>
         /// 重写改方法后请一起重写IncrementMinutes值，比如你按月分表但是你设置cron表达式为月中的时候建表，
         /// 那么会在月中的时候 <code>DateTime.Now.AddMinutes(IncrementMinutes);</code>来获取tail会导致还是当月的所以不会建表
@@ -99,6 +115,7 @@ namespace ShardingCore.VirtualRoutes.Abstractions
         /// <returns></returns>
         protected abstract string ConvertNowToTail(DateTime now);
 
+
         public virtual Task ExecuteAsync()
         {
             var logger=RouteShardingProvider

src/ShardingCore/VirtualRoutes/Days/AbstractSimpleShardingDayKeyDateTimeVirtualTableRoute.cs

@@ -85,5 +85,10 @@ namespace ShardingCore.VirtualRoutes.Days
             };
         }
 
+        public override string[] GetCompensateCronExpressions()
+        {
+            return new[] { "0 0 0 * * ?" };
+        }
+
     }
 }

src/ShardingCore/VirtualRoutes/Days/AbstractSimpleShardingDayKeyLongVirtualTableRoute.cs

@@ -80,5 +80,9 @@ namespace ShardingCore.VirtualRoutes.Days
                 "0 1 0 * * ?",
             };
         }
+        public override string[] GetCompensateCronExpressions()
+        {
+            return new[] { "0 0 0 * * ?" };
+        }
     }
 }

src/ShardingCore/VirtualRoutes/Months/AbstractSimpleShardingMonthKeyDateTimeVirtualTableRoute.cs

@@ -76,6 +76,10 @@ namespace ShardingCore.VirtualRoutes.Months
                 "0 1 0 1 * ?",
             };
         }
+        public override string[] GetCompensateCronExpressions()
+        {
+            return new[] { "0 0 0 1 * ?" };
+        }
 
     }
 }

src/ShardingCore/VirtualRoutes/Months/AbstractSimpleShardingMonthKeyLongVirtualTableRoute.cs

@@ -79,5 +79,9 @@ namespace ShardingCore.VirtualRoutes.Months
                 "0 1 0 1 * ?",
             };
         }
+        public override string[] GetCompensateCronExpressions()
+        {
+            return new[] { "0 0 0 1 * ?" };
+        }
     }
 }

src/ShardingCore/VirtualRoutes/Weeks/AbstractSimpleShardingWeekKeyDateTimeVirtualTableRoute.cs

@@ -78,6 +78,10 @@ namespace ShardingCore.VirtualRoutes.Weeks
                 "0 1 0 ? * 2",
             };
         }
+        public override string[] GetCompensateCronExpressions()
+        {
+            return new[] { "0 0 0 ? * 2" };
+        }
 
     }
 }

src/ShardingCore/VirtualRoutes/Weeks/AbstractSimpleShardingWeekKeyLongVirtualTableRoute.cs

@@ -81,5 +81,9 @@ namespace ShardingCore.VirtualRoutes.Weeks
                 "0 1 0 ? * 2",
             };
         }
+        public override string[] GetCompensateCronExpressions()
+        {
+            return new[] { "0 0 0 ? * 2" };
+        }
     }
 }

src/ShardingCore/VirtualRoutes/Years/AbstractSimpleShardingYearKeyDateTimeVirtualTableRoute.cs

@@ -78,5 +78,9 @@ namespace ShardingCore.VirtualRoutes.Years
                 "0 1 0 1 1 ?",
             };
         }
+        public override string[] GetCompensateCronExpressions()
+        {
+            return new[] { "0 0 0 1 1 ?" };
+        }
     }
 }

src/ShardingCore/VirtualRoutes/Years/AbstractSimpleShardingYearKeyLongVirtualTableRoute.cs

@@ -102,5 +102,9 @@ namespace ShardingCore.VirtualRoutes.Years
                 "0 1 0 1 1 ?",
             };
         }
+        public override string[] GetCompensateCronExpressions()
+        {
+            return new[] { "0 0 0 1 1 ?" };
+        }
     }
 }