WF4.0基礎篇 (十九) Persistence持久化

Persistence 持久化

WF4提供了一個抽象類System.Runtime.Persistence.InstanceStore，用於定義持久化的實現.該類來自於 System.Runtime.dll

可以從InstanceStore類繼承來開發Persistence Provider,持久化過程中的對實例的數據訪問需要另外一個繼 承自System.Activities.Persistence.PersistenceParticipant

WF4提供了一個基於SQL Server的持久化類 SqlWorkflowInstanceStore

持久化的所有者

當只對實例進行持久化([實 例.PersistableIdle = PersistableIdleAction.Persist] 或instance.Persist(),或Persist Activity),而沒將實例時UnLoad時,該持久 化的實例被其所有者鎖定.如果對Load持久化的實例不是該實例的所有者,會報如下異常:

The execution of an InstancePersistenceCommand was interrupted because the instance 'c42a0d7d-d652-404a-9734- 67acb163ea48' is locked by a different instance owner. This error usually occurs because a different host has the instance loaded. The instance owner ID of the owner or host with a lock on the instance is 'c9959a30-60aa-47ae-a119- bc8ff1b97720'.

因為實例"c42a0d7d-d652-404a-9734-67acb163ea48"一個不同的實例的所有者被鎖定，被打斷了一個 InstancePersistenceCommand 的執 行。因為不同的主機有實例加載時，通常會發生此錯誤。實例的擁有人或主機實例上的鎖的所有者 ID 是 ' c9959a30-60aa-47ae-a119- bc8ff1b97720。

關於Activity.CacheMetadata方法

注意:Activity.CacheMetadata方法會多次被調用

流程中的Activity.CacheMetadata 方法會在Run時全部調用,

每當從持久化中Load實例時,Activity.CacheMetadata方法會再次全部調用

與持久化相關的事件執 行順序

實例.PersistableIdle

實例.Idle

實例.Unloaded

當實例完成後,執行完[實例.Completed]後才執行[ 實例.Unloaded]

SqlWorkflowInstanceStore 數據庫

\Windows\Microsoft.NET\Framework\v4.0.21006 \SQL\en SqlWorkflowInstanceStoreSchema.sql

 

SqlWorkflowInstanceStoreLogic.sql

SqlWorkflowInstanceStore 類

類名

System.Activities.DurableInstancing.SqlWorkflowInstanceStore

文件

System.Activities.DurableInstancing.dll

System.Runtime.dll

結構說明

繼承 InstanceStore

是一個 sealed類

override 了 [BeginTryCommand方法] 與 [EndTryCommand方法]與 [OnFreeInstanceHandle方法]與 [OnNewInstanceHandle方法]

[ConnectionString]屬性 的類型為[string]

[EnqueueRunCommands]屬性 的類型為[bool]

[HostLockRenewalPeriod]屬性 的類型為[TimeSpan]

[InstanceCompletionAction]屬性 的類型為[InstanceCompletionAction]

[InstanceEncodingOption]屬性 的類型為 [InstanceEncodingOption]

[InstanceLockedExceptionAction]屬性 的類型為[InstanceLockedExceptionAction]

無返回值 [Promote]方法,(string name, IEnumerable<XName> promoteAsVariant, IEnumerable<XName> promoteAsBinary)

功能說明

[ConnectionString]屬性 ,數據庫字串

[EnqueueRunCommands]屬性,

[HostLockRenewalPeriod]屬性,服務宿主在指定時間內必須更新鎖定時間周期

[InstanceCompletionAction]屬性,實例完成後是否 刪除持久化存儲中的數據，DeleteAll(默認)，DeleteNothing

[InstanceEncodingOption]屬性,保存到持久化存儲的壓縮算法， None(默認),GZip,

[InstanceLockedExceptionAction] 屬性,當發生InstanceLockedException異常時(該異常發生在當他要去鎖定 已經被其他服務宿主鎖定的實例時)的操作 NoRetry(默認)，BasicRetry，AggressiveRetry

[Promote]方法

PersistableIdleAction.Unload方式持久化

要將實例持久化，有很多種方式可以使用，其中一種就是使用[實 例.PersistableIdle 回調函數]，它在實例Idle時觸發。

當 [實例.PersistableIdle = e => PersistableIdleAction.Persist],實例被持久化,但並沒有被UnLoad,這時Load時要主意持久化的所有者

當 [實 例.PersistableIdle = e => PersistableIdleAction.UnLoad],實例被持久化,然後被UnLoad,這時Load時不用考慮所有者

//===================================================

WorkflowApplication　instance　=　null;

void　workflowCompleted(WorkflowApplicationCompletedEventArgs　e)
{
instance　=　null;
System.Console.WriteLine("workflowCompleted:{0}",　e.CompletionState.ToString());
}

void　workflowIdel (WorkflowApplicationIdleEventArgs　e)
{

System.Console.WriteLine("Idle:{0}",　e.InstanceId);
}

void　unload(WorkflowApplicationEventArgs　e)
{
System.Console.WriteLine("unload:{0}",　 e.InstanceId);
}
PersistableIdleAction　persistableIdle(WorkflowApplicationIdleEventArgs　e)
{

System.Console.WriteLine("persistableIdle:{0}",　e.InstanceId);

return　PersistableIdleAction.Unload;
}
//==================================================

void　triggering()
{
string　bookName 　=　textBox_bookmark.Text;
string　inputValue　=　textBox_value.Text;

if　(instance　!=　null)
{
if　(instance.GetBookmarks().Count(p　=>　p.BookmarkName　==　bookName)　==　1)
{
instance.ResumeBookmark (bookName,　inputValue);
}
}
}

void　create()
{
instance　=　new　 WorkflowApplication(new　FlowcharLibrary.FlowDecisionWorkflow());

//
string　connectionString　=　"Data　 Source=.;Initial　Catalog=WorkflowInstanceStore;Integrated　Security=True";
SqlWorkflowInstanceStore　instanceStore 　=　new　SqlWorkflowInstanceStore(connectionString);

instance.InstanceStore　=　instanceStore;

instance.PersistableIdle　=　persistableIdle;

instance.Idle　=　workflowIdel;

instance.Unloaded　 =　unload;

instance.Completed　=　workflowCompleted;

textBox_Guid.Text　=　instance.Id.ToString ();
instance.Run();
}

void　load()
{
instance　=　new　WorkflowApplication(new　 FlowcharLibrary.FlowDecisionWorkflow());

//
string　connectionString　=　"Data　Source=.;Initial　 Catalog=WorkflowInstanceStore;Integrated　Security=True";
SqlWorkflowInstanceStore　instanceStore　=　new　 SqlWorkflowInstanceStore(connectionString);

instance.InstanceStore　=　instanceStore;
instance.PersistableIdle　=　persistableIdle;

instance.Completed　=　workflowCompleted;
instance.Unloaded　=　unload;
instance.Idle　=　workflowIdel;

Guid　guid　=　new　Guid (textBox_Guid.Text);

instance.Load(guid);

}

手動方式持久化

可以不使用[實 例.PersistableIdle = e => PersistableIdleAction.UnLoad]的方式持久化實例而使用

[實例.Persist方法] 與 [實例.Unload 方法] 方式,

[實例.Unload方法]會觸發[實例.Unload事件]

void　unload()
{
instance.Persist();
instance.Unload();
}

InstanceView

類名 System.Runtime.Persistence.InstanceView 文件 System.Runtime.dll 結構說 明 繼承 Object

 

是一個 sealed類

[InstanceData]屬性 的類型為[ IDictionary<XName, InstanceValue>]

[InstanceDataConsistency]屬性 的類型為[InstanceValueConsistency]

[InstanceId]屬性 的類型為[Guid]

[InstanceKeys]屬性 的類型為[ IDictionary<Guid, InstanceKeyView>]

[InstanceKeysConsistency]屬性 的類型為[ InstanceValueConsistency]

[InstanceMetadata]屬性 的類型為[ IDictionary<XName, InstanceValue>]

[InstanceMetadataConsistency]屬性 的類型為[ InstanceValueConsistency ]

[InstanceOwner]屬性 的類型為[ InstanceOwner]

[InstanceOwnerMetadata]屬性 的類型為[IDictionary<XName, InstanceValue>]

[InstanceOwnerMetadataConsistency]屬性 的類型為[InstanceValueConsistency]

[InstanceState]屬性 的類型為 [InstanceState]

[InstanceStoreQueryResults]屬性 的類型為
[ReadOnlyCollection<InstanceStoreQueryResult>]

[IsBoundToInstance]屬性 的類型為[bool]

[IsBoundToInstanceOwner]屬性 的類型為[bool]

[IsBoundToLock]屬性 的類型為[bool]

功能說明  

基本使用

//===================================================

WorkflowApplication　instance　=　null;

SqlWorkflowInstanceStore　instanceStore;

InstanceView　view;

void　workflowCompleted (WorkflowApplicationCompletedEventArgs　e)
{
instance　=　null;
System.Console.WriteLine ("workflowCompleted:{0}",　e.CompletionState.ToString());
}

void　workflowIdel (WorkflowApplicationIdleEventArgs　e)
{

System.Console.WriteLine("Idle:{0}",　e.InstanceId);
}

void　unload(WorkflowApplicationEventArgs　e)
{
System.Console.WriteLine("unload:{0}",　 e.InstanceId);
}

PersistableIdleAction　persistableIdle(WorkflowApplicationIdleEventArgs　e)
{

System.Console.WriteLine("persistableIdle:{0}",　e.InstanceId);

return　 PersistableIdleAction.Unload;
}
//==================================================

void　create()
{
instance　=　new　WorkflowApplication(new　FlowcharLibrary.FlowDecisionWorkflow());

//
if　 (instanceStore　==　null)
{
string　connectionString　=　"Data　Source=.;Initial　 Catalog=WorkflowInstanceStore;Integrated　Security=True";
instanceStore　=　new　SqlWorkflowInstanceStore (connectionString);
view　=　instanceStore.Execute(instanceStore.CreateInstanceHandle(),　new　 CreateWorkflowOwnerCommand(),　TimeSpan.FromSeconds(30));
instanceStore.DefaultInstanceOwner　=　 view.InstanceOwner;
}

instance.InstanceStore　=　instanceStore;

instance.PersistableIdle　=　 persistableIdle;

instance.Idle　=　workflowIdel;

instance.Unloaded　=　unload;

instance.Completed　=　workflowCompleted;

textBox_Guid.Text　=　instance.Id.ToString();
instance.Run ();
}

void　load()
{
instance　=　new　WorkflowApplication(new　 FlowcharLibrary.FlowDecisionWorkflow());

if　(instanceStore　==　null)
{
string　connectionString　= 　"Data　Source=.;Initial　Catalog=WorkflowInstanceStore;Integrated　Security=True";
instanceStore　=　new　 SqlWorkflowInstanceStore(connectionString);
view　=　instanceStore.Execute(instanceStore.CreateInstanceHandle(),　 new　CreateWorkflowOwnerCommand(),　TimeSpan.FromSeconds(30));

instanceStore.DefaultInstanceOwner　=　 view.InstanceOwner;
}

instance.InstanceStore　=　instanceStore;

instance.PersistableIdle　=　 persistableIdle;

instance.Idle　=　workflowIdel;

instance.Unloaded　=　unload;

instance.Completed　=　workflowCompleted;

Guid　guid　=　new　Guid(textBox_Guid.Text);

instance.Load(guid);

}

void　triggering()
{
string　bookName　=　 textBox_bookmark.Text;
string　inputValue　=　textBox_value.Text;

if　(instance　!=　null)
{
if 　(instance.GetBookmarks().Count(p　=>　p.BookmarkName　==　bookName)　==　1)
{
instance.ResumeBookmark (bookName,　inputValue);
}
}
}

Persist Activity 方式持久化

使用Persist Activity，可以在 其出現的位置使實例持久化，不管實例是否處於Idle狀態.

類名 System.Activities.Statements.Persist 文件 System.Activities.dll 結構說 明 繼承 NativeActivity

 

是一個 sealed類

override 了 [CacheMetadata方法] 與 [Execute方法]

功能說明 [Persist] 可以觸發[Idel]

例:基本使用

工作流

宿主

WorkflowApplication　instance　=　null;
SqlWorkflowInstanceStore　instanceStore;
InstanceView　view;
void　workflowCompleted(WorkflowApplicationCompletedEventArgs　e)
{
instance　=　null;
System.Console.WriteLine("workflowCompleted:{0}",　e.CompletionState.ToString ());
}
void　workflowIdel(WorkflowApplicationIdleEventArgs　e)
{
System.Console.WriteLine("Idle:{0}",　e.InstanceId);
}
void　unload(WorkflowApplicationEventArgs　e)
{
System.Console.WriteLine("unload:{0}",　e.InstanceId);
}
//==================================================
private　void　button_PersistWorkflow_Click(object　sender,　RoutedEventArgs　e)
{
instance　=　new　WorkflowApplication(new　PersistenceWindow.PersistWorkflow ());
//
if　(instanceStore　==　null)
{
string　connectionString　=　"Data　Source=.;Initial Catalog=WorkflowInstanceStore;Integrated　Security=True";
instanceStore　=　new　SqlWorkflowInstanceStore (connectionString);
view　=　instanceStore.Execute(instanceStore.CreateInstanceHandle(),　new　CreateWorkflowOwnerCommand(),　TimeSpan.FromSeconds(30));
instanceStore.DefaultInstanceOwner　=　view.InstanceOwner;
}
instance.InstanceStore　=　instanceStore;
instance.Idle　=　workflowIdel;
instance.Unloaded　=　unload;
instance.Completed　=　workflowCompleted;
textBox_Guid.Text　=　instance.Id.ToString();
instance.Run();
}

結果

本文 例子下載：http://files.cnblogs.com/foundation/PersistenceSample.rar