Code:
/ 4.0 / 4.0 / DEVDIV_TFS / Dev10 / Releases / RTMRel / ndp / fx / src / DataWeb / Server / System / Data / Services / DataServiceProcessingPipeline.cs / 1305376 / DataServiceProcessingPipeline.cs
//----------------------------------------------------------------------
//
// Copyright (c) Microsoft Corporation. All rights reserved.
//
//
// Class declaring events for the data service processing pipeline
//
//
// @owner [....]
//---------------------------------------------------------------------
namespace System.Data.Services
{
using System;
using System.Diagnostics;
///
/// Class declaring the events for the data service processing pipeline
///
public sealed class DataServiceProcessingPipeline
{
#if DEBUG
// ***************************************************************************************
// The debug code here is for basic assertions on call orders if the request is successful.
// ***************************************************************************************
///
/// Number of times InvokeProcessingRequest() is called.
///
private int ProcessingRequestInvokeCount;
///
/// Number of times InvokeProcessedRequest() is called
///
private int ProcessedRequestInvokeCount;
///
/// Number of times InvokeProcessingChangeset() is called
///
private int ProcessingChangesetInvokeCount;
///
/// Number of times InvokeProcessedChangeset() is called
///
private int ProcessedChangesetInvokeCount;
///
/// Set to true if we have seen an exception in the current request or we are in the $metadata path
///
///
/// If the current request encounters an exception, there is no guarantee that all the
/// events will be fired, we may skip the debug asserts when that happens.
///
internal bool SkipDebugAssert;
///
/// Set to true if DataServiceProviderWrapper.GetService() is called.
///
internal bool HasInstantiatedProviderInterfaces;
///
/// Set to true if any of the service is disposed from WebUtil.Dispose()
///
internal bool HasDisposedProviderInterfaces;
///
/// Number of times DataService<T>.OnStartProcessingRequest() is called.
///
internal int OnStartProcessingRequestInvokeCount;
#endif
///
/// Request start event
///
public event EventHandler ProcessingRequest;
///
/// Request end event
///
public event EventHandler ProcessedRequest;
///
/// Change set start event
///
public event EventHandler ProcessingChangeset;
///
/// Change set end event
///
public event EventHandler ProcessedChangeset;
#if DEBUG
///
/// Assert ProcessingPipeline state before any event has been fired
///
internal void AssertInitialDebugState()
{
Debug.Assert(!this.HasInstantiatedProviderInterfaces, "!this.HasInstantiatedProviderInterfaces");
Debug.Assert(!this.HasDisposedProviderInterfaces, "!this.HasDisposedProviderInterfaces");
Debug.Assert(this.OnStartProcessingRequestInvokeCount == 0, "this.OnStartProcessingRequestInvokeCount == 0");
Debug.Assert(this.ProcessingRequestInvokeCount == 0, "this.ProcessingRequestInvokeCount == 0");
Debug.Assert(this.ProcessedRequestInvokeCount == 0, "this.ProcessedRequestInvokeCount == 0");
Debug.Assert(this.ProcessingChangesetInvokeCount == 0, "this.ProcessingChangesetInvokeCount == 0");
Debug.Assert(this.ProcessedChangesetInvokeCount == 0, "this.ProcessedChangesetInvokeCount == 0");
}
///
/// Assert ProcessingPipeline state at DataService<T>.OnStartProcessingRequest
///
internal void AssertDebugStateAtOnStartProcessingRequest()
{
// If the current request encounters an exception, there is no guarantee that all the
// events will be fired, we skip the debug asserts when that happens.
if (!this.SkipDebugAssert)
{
Debug.Assert(
this.OnStartProcessingRequestInvokeCount > 0 || !this.HasInstantiatedProviderInterfaces,
"this.OnStartProcessingRequestInvokeCount > 0 || !this.HasInstantiatedProviderInterfaces");
Debug.Assert(!this.HasDisposedProviderInterfaces, "!this.HasDisposedProviderInterfaces");
Debug.Assert(this.ProcessingRequestInvokeCount == 1, "this.ProcessingRequestInvokeCount == 1");
Debug.Assert(this.ProcessedRequestInvokeCount == 0, "this.ProcessedRequestInvokeCount == 0");
Debug.Assert(
this.ProcessingChangesetInvokeCount == this.ProcessedChangesetInvokeCount || this.ProcessingChangesetInvokeCount == this.ProcessedChangesetInvokeCount + 1,
"this.ProcessingChangesetInvokeCount == this.ProcessedChangesetInvokeCount || this.ProcessingChangesetInvokeCount == this.ProcessedChangesetInvokeCount + 1");
}
}
///
/// Assert ProcessingPipeline state before disposing provider interfaces
///
internal void AssertDebugStateAtDispose()
{
// If the current request encounters an exception, there is no guarantee that all the
// events will be fired, we skip the debug asserts when that happens.
if (!this.SkipDebugAssert)
{
Debug.Assert(this.OnStartProcessingRequestInvokeCount > 0, "this.OnStartProcessingRequestInvokeCount > 0");
Debug.Assert(this.ProcessingRequestInvokeCount == 1, "this.ProcessingRequestInvokeCount == 1");
Debug.Assert(this.ProcessedRequestInvokeCount == 1, "this.ProcessedRequestInvokeCount == 1");
Debug.Assert(
this.ProcessingChangesetInvokeCount == this.ProcessedChangesetInvokeCount,
"this.ProcessingChangesetInvokeCount == this.ProcessedChangesetInvokeCount");
}
}
///
/// Assert Processing Pipeline state during request processing
///
/// data service instance
internal void AssertDebugStateDuringRequestProcessing(IDataService dataService)
{
// If the current request encounters an exception, there is no guarantee that all the
// events will be fired, we skip the debug asserts when that happens.
if (!this.SkipDebugAssert)
{
Debug.Assert(!this.HasDisposedProviderInterfaces, "!this.HasDisposedProviderInterfaces");
Debug.Assert(this.OnStartProcessingRequestInvokeCount > 0, "this.OnStartProcessingRequestInvokeCount > 0");
Debug.Assert(this.ProcessingRequestInvokeCount == 1, "this.ProcessingRequestInvokeCount == 1");
Debug.Assert(
(this.ProcessingChangesetInvokeCount == this.ProcessedChangesetInvokeCount && dataService.OperationContext.Host.AstoriaHttpVerb == AstoriaVerbs.GET) ||
(this.ProcessingChangesetInvokeCount == this.ProcessedChangesetInvokeCount + 1 && dataService.OperationContext.Host.AstoriaHttpVerb != AstoriaVerbs.GET),
"ProcessingChangesetInvokeCount must be 1 larger than ProcessedChangesetInvokeCount in CUD operation and they must be the same in a GET request.");
}
}
///
/// Need to be able to reset the states since the caller can reuse the same service instance.
///
internal void ResetDebugState()
{
this.HasInstantiatedProviderInterfaces = false;
this.HasDisposedProviderInterfaces = false;
this.OnStartProcessingRequestInvokeCount = 0;
this.ProcessingRequestInvokeCount = 0;
this.ProcessedRequestInvokeCount = 0;
this.ProcessingChangesetInvokeCount = 0;
this.ProcessedChangesetInvokeCount = 0;
}
#endif
///
/// Invoke request start event
///
/// Sender, i.e. data service instance.
/// event arg
internal void InvokeProcessingRequest(object sender, DataServiceProcessingPipelineEventArgs e)
{
#if DEBUG
this.AssertInitialDebugState();
this.ProcessingRequestInvokeCount++;
#endif
if (this.ProcessingRequest != null)
{
this.ProcessingRequest(sender, e);
}
}
///
/// Invoke request end event
///
/// Sender, i.e. data service instance.
/// event arg
internal void InvokeProcessedRequest(object sender, DataServiceProcessingPipelineEventArgs e)
{
#if DEBUG
Debug.Assert(!this.HasDisposedProviderInterfaces, "!this.HasDisposedProviderInterfaces");
Debug.Assert(this.OnStartProcessingRequestInvokeCount > 0, "this.OnStartProcessingRequestInvokeCount > 0");
Debug.Assert(this.ProcessingRequestInvokeCount == 1, "this.ProcessingRequestInvokeCount == 1");
Debug.Assert(this.ProcessedRequestInvokeCount == 0, "this.ProcessedRequestInvokeCount == 0");
if (!this.SkipDebugAssert)
{
Debug.Assert(this.ProcessingChangesetInvokeCount == this.ProcessedChangesetInvokeCount, "this.ProcessingChangesetInvokeCount == this.ProcessedChangesetInvokeCount");
}
this.ProcessedRequestInvokeCount++;
#endif
if (this.ProcessedRequest != null)
{
this.ProcessedRequest(sender, e);
}
}
///
/// Invoke change set start event
///
/// Sender, i.e. data service instance.
/// event arg
internal void InvokeProcessingChangeset(object sender, EventArgs e)
{
#if DEBUG
Debug.Assert(!this.HasDisposedProviderInterfaces, "!this.HasDisposedProviderInterfaces");
Debug.Assert(this.OnStartProcessingRequestInvokeCount > 0, "this.OnStartProcessingRequestInvokeCount > 0");
Debug.Assert(this.ProcessingRequestInvokeCount == 1, "this.ProcessingRequestInvokeCount == 1");
Debug.Assert(this.ProcessedRequestInvokeCount == 0, "this.ProcessedRequestInvokeCount == 0");
if (!this.SkipDebugAssert)
{
Debug.Assert(this.ProcessingChangesetInvokeCount == this.ProcessedChangesetInvokeCount, "this.ProcessingChangesetInvokeCount == this.ProcessedChangesetInvokeCount");
}
this.ProcessingChangesetInvokeCount++;
#endif
if (this.ProcessingChangeset != null)
{
this.ProcessingChangeset(sender, e);
}
}
///
/// Invoke change set end event
///
/// Sender, i.e. data service instance.
/// event arg
internal void InvokeProcessedChangeset(object sender, EventArgs e)
{
#if DEBUG
Debug.Assert(!this.HasDisposedProviderInterfaces, "!this.HasDisposedProviderInterfaces");
Debug.Assert(this.OnStartProcessingRequestInvokeCount > 0, "this.OnStartProcessingRequestInvokeCount > 0");
Debug.Assert(this.ProcessingRequestInvokeCount == 1, "this.ProcessingRequestInvokeCount == 1");
Debug.Assert(this.ProcessedRequestInvokeCount == 0, "this.ProcessedRequestInvokeCount == 0");
if (!this.SkipDebugAssert)
{
Debug.Assert(this.ProcessingChangesetInvokeCount == this.ProcessedChangesetInvokeCount + 1, "this.ProcessingChangesetInvokeCount == this.ProcessedChangesetInvokeCount + 1");
}
this.ProcessedChangesetInvokeCount++;
#endif
if (this.ProcessedChangeset != null)
{
this.ProcessedChangeset(sender, e);
}
}
}
}
// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
//----------------------------------------------------------------------
//
// Copyright (c) Microsoft Corporation. All rights reserved.
//
//
// Class declaring events for the data service processing pipeline
//
//
// @owner [....]
//---------------------------------------------------------------------
namespace System.Data.Services
{
using System;
using System.Diagnostics;
///
/// Class declaring the events for the data service processing pipeline
///
public sealed class DataServiceProcessingPipeline
{
#if DEBUG
// ***************************************************************************************
// The debug code here is for basic assertions on call orders if the request is successful.
// ***************************************************************************************
///
/// Number of times InvokeProcessingRequest() is called.
///
private int ProcessingRequestInvokeCount;
///
/// Number of times InvokeProcessedRequest() is called
///
private int ProcessedRequestInvokeCount;
///
/// Number of times InvokeProcessingChangeset() is called
///
private int ProcessingChangesetInvokeCount;
///
/// Number of times InvokeProcessedChangeset() is called
///
private int ProcessedChangesetInvokeCount;
///
/// Set to true if we have seen an exception in the current request or we are in the $metadata path
///
///
/// If the current request encounters an exception, there is no guarantee that all the
/// events will be fired, we may skip the debug asserts when that happens.
///
internal bool SkipDebugAssert;
///
/// Set to true if DataServiceProviderWrapper.GetService() is called.
///
internal bool HasInstantiatedProviderInterfaces;
///
/// Set to true if any of the service is disposed from WebUtil.Dispose()
///
internal bool HasDisposedProviderInterfaces;
///
/// Number of times DataService<T>.OnStartProcessingRequest() is called.
///
internal int OnStartProcessingRequestInvokeCount;
#endif
///
/// Request start event
///
public event EventHandler ProcessingRequest;
///
/// Request end event
///
public event EventHandler ProcessedRequest;
///
/// Change set start event
///
public event EventHandler ProcessingChangeset;
///
/// Change set end event
///
public event EventHandler ProcessedChangeset;
#if DEBUG
///
/// Assert ProcessingPipeline state before any event has been fired
///
internal void AssertInitialDebugState()
{
Debug.Assert(!this.HasInstantiatedProviderInterfaces, "!this.HasInstantiatedProviderInterfaces");
Debug.Assert(!this.HasDisposedProviderInterfaces, "!this.HasDisposedProviderInterfaces");
Debug.Assert(this.OnStartProcessingRequestInvokeCount == 0, "this.OnStartProcessingRequestInvokeCount == 0");
Debug.Assert(this.ProcessingRequestInvokeCount == 0, "this.ProcessingRequestInvokeCount == 0");
Debug.Assert(this.ProcessedRequestInvokeCount == 0, "this.ProcessedRequestInvokeCount == 0");
Debug.Assert(this.ProcessingChangesetInvokeCount == 0, "this.ProcessingChangesetInvokeCount == 0");
Debug.Assert(this.ProcessedChangesetInvokeCount == 0, "this.ProcessedChangesetInvokeCount == 0");
}
///
/// Assert ProcessingPipeline state at DataService<T>.OnStartProcessingRequest
///
internal void AssertDebugStateAtOnStartProcessingRequest()
{
// If the current request encounters an exception, there is no guarantee that all the
// events will be fired, we skip the debug asserts when that happens.
if (!this.SkipDebugAssert)
{
Debug.Assert(
this.OnStartProcessingRequestInvokeCount > 0 || !this.HasInstantiatedProviderInterfaces,
"this.OnStartProcessingRequestInvokeCount > 0 || !this.HasInstantiatedProviderInterfaces");
Debug.Assert(!this.HasDisposedProviderInterfaces, "!this.HasDisposedProviderInterfaces");
Debug.Assert(this.ProcessingRequestInvokeCount == 1, "this.ProcessingRequestInvokeCount == 1");
Debug.Assert(this.ProcessedRequestInvokeCount == 0, "this.ProcessedRequestInvokeCount == 0");
Debug.Assert(
this.ProcessingChangesetInvokeCount == this.ProcessedChangesetInvokeCount || this.ProcessingChangesetInvokeCount == this.ProcessedChangesetInvokeCount + 1,
"this.ProcessingChangesetInvokeCount == this.ProcessedChangesetInvokeCount || this.ProcessingChangesetInvokeCount == this.ProcessedChangesetInvokeCount + 1");
}
}
///
/// Assert ProcessingPipeline state before disposing provider interfaces
///
internal void AssertDebugStateAtDispose()
{
// If the current request encounters an exception, there is no guarantee that all the
// events will be fired, we skip the debug asserts when that happens.
if (!this.SkipDebugAssert)
{
Debug.Assert(this.OnStartProcessingRequestInvokeCount > 0, "this.OnStartProcessingRequestInvokeCount > 0");
Debug.Assert(this.ProcessingRequestInvokeCount == 1, "this.ProcessingRequestInvokeCount == 1");
Debug.Assert(this.ProcessedRequestInvokeCount == 1, "this.ProcessedRequestInvokeCount == 1");
Debug.Assert(
this.ProcessingChangesetInvokeCount == this.ProcessedChangesetInvokeCount,
"this.ProcessingChangesetInvokeCount == this.ProcessedChangesetInvokeCount");
}
}
///
/// Assert Processing Pipeline state during request processing
///
/// data service instance
internal void AssertDebugStateDuringRequestProcessing(IDataService dataService)
{
// If the current request encounters an exception, there is no guarantee that all the
// events will be fired, we skip the debug asserts when that happens.
if (!this.SkipDebugAssert)
{
Debug.Assert(!this.HasDisposedProviderInterfaces, "!this.HasDisposedProviderInterfaces");
Debug.Assert(this.OnStartProcessingRequestInvokeCount > 0, "this.OnStartProcessingRequestInvokeCount > 0");
Debug.Assert(this.ProcessingRequestInvokeCount == 1, "this.ProcessingRequestInvokeCount == 1");
Debug.Assert(
(this.ProcessingChangesetInvokeCount == this.ProcessedChangesetInvokeCount && dataService.OperationContext.Host.AstoriaHttpVerb == AstoriaVerbs.GET) ||
(this.ProcessingChangesetInvokeCount == this.ProcessedChangesetInvokeCount + 1 && dataService.OperationContext.Host.AstoriaHttpVerb != AstoriaVerbs.GET),
"ProcessingChangesetInvokeCount must be 1 larger than ProcessedChangesetInvokeCount in CUD operation and they must be the same in a GET request.");
}
}
///
/// Need to be able to reset the states since the caller can reuse the same service instance.
///
internal void ResetDebugState()
{
this.HasInstantiatedProviderInterfaces = false;
this.HasDisposedProviderInterfaces = false;
this.OnStartProcessingRequestInvokeCount = 0;
this.ProcessingRequestInvokeCount = 0;
this.ProcessedRequestInvokeCount = 0;
this.ProcessingChangesetInvokeCount = 0;
this.ProcessedChangesetInvokeCount = 0;
}
#endif
///
/// Invoke request start event
///
/// Sender, i.e. data service instance.
/// event arg
internal void InvokeProcessingRequest(object sender, DataServiceProcessingPipelineEventArgs e)
{
#if DEBUG
this.AssertInitialDebugState();
this.ProcessingRequestInvokeCount++;
#endif
if (this.ProcessingRequest != null)
{
this.ProcessingRequest(sender, e);
}
}
///
/// Invoke request end event
///
/// Sender, i.e. data service instance.
/// event arg
internal void InvokeProcessedRequest(object sender, DataServiceProcessingPipelineEventArgs e)
{
#if DEBUG
Debug.Assert(!this.HasDisposedProviderInterfaces, "!this.HasDisposedProviderInterfaces");
Debug.Assert(this.OnStartProcessingRequestInvokeCount > 0, "this.OnStartProcessingRequestInvokeCount > 0");
Debug.Assert(this.ProcessingRequestInvokeCount == 1, "this.ProcessingRequestInvokeCount == 1");
Debug.Assert(this.ProcessedRequestInvokeCount == 0, "this.ProcessedRequestInvokeCount == 0");
if (!this.SkipDebugAssert)
{
Debug.Assert(this.ProcessingChangesetInvokeCount == this.ProcessedChangesetInvokeCount, "this.ProcessingChangesetInvokeCount == this.ProcessedChangesetInvokeCount");
}
this.ProcessedRequestInvokeCount++;
#endif
if (this.ProcessedRequest != null)
{
this.ProcessedRequest(sender, e);
}
}
///
/// Invoke change set start event
///
/// Sender, i.e. data service instance.
/// event arg
internal void InvokeProcessingChangeset(object sender, EventArgs e)
{
#if DEBUG
Debug.Assert(!this.HasDisposedProviderInterfaces, "!this.HasDisposedProviderInterfaces");
Debug.Assert(this.OnStartProcessingRequestInvokeCount > 0, "this.OnStartProcessingRequestInvokeCount > 0");
Debug.Assert(this.ProcessingRequestInvokeCount == 1, "this.ProcessingRequestInvokeCount == 1");
Debug.Assert(this.ProcessedRequestInvokeCount == 0, "this.ProcessedRequestInvokeCount == 0");
if (!this.SkipDebugAssert)
{
Debug.Assert(this.ProcessingChangesetInvokeCount == this.ProcessedChangesetInvokeCount, "this.ProcessingChangesetInvokeCount == this.ProcessedChangesetInvokeCount");
}
this.ProcessingChangesetInvokeCount++;
#endif
if (this.ProcessingChangeset != null)
{
this.ProcessingChangeset(sender, e);
}
}
///
/// Invoke change set end event
///
/// Sender, i.e. data service instance.
/// event arg
internal void InvokeProcessedChangeset(object sender, EventArgs e)
{
#if DEBUG
Debug.Assert(!this.HasDisposedProviderInterfaces, "!this.HasDisposedProviderInterfaces");
Debug.Assert(this.OnStartProcessingRequestInvokeCount > 0, "this.OnStartProcessingRequestInvokeCount > 0");
Debug.Assert(this.ProcessingRequestInvokeCount == 1, "this.ProcessingRequestInvokeCount == 1");
Debug.Assert(this.ProcessedRequestInvokeCount == 0, "this.ProcessedRequestInvokeCount == 0");
if (!this.SkipDebugAssert)
{
Debug.Assert(this.ProcessingChangesetInvokeCount == this.ProcessedChangesetInvokeCount + 1, "this.ProcessingChangesetInvokeCount == this.ProcessedChangesetInvokeCount + 1");
}
this.ProcessedChangesetInvokeCount++;
#endif
if (this.ProcessedChangeset != null)
{
this.ProcessedChangeset(sender, e);
}
}
}
}
// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
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