#include <VirtualizationSystem.h>

Inheritance diagram for UE::Virtualization::IVirtualizationSystem:

Public Types
enum	ENotification { PushBegunNotification , PushEndedNotification , PushFailedNotification , PullBegunNotification , PullEndedNotification , PullFailedNotification }

using	GetPayloadActivityInfoFuncRef = TFunctionRef< void(const FString &DebugName, const FString &ConfigName, const FPayloadActivityInfo &PayloadInfo)>

using	FOnNotification = TTSMulticastDelegate< void(ENotification, const FIoHash &)>

Public Member Functions
	IVirtualizationSystem ()=default

virtual	~IVirtualizationSystem ()=default

virtual bool	Initialize (const FInitParams &InitParams)=0

virtual bool	IsEnabled () const =0

virtual bool	IsPushingEnabled (EStorageType StorageType) const =0

virtual EPayloadFilterReason	FilterPayload (const UObject *Owner) const =0

virtual bool	AllowSubmitIfVirtualizationFailed () const =0

virtual bool	PushData (TArrayView< FPushRequest > Requests, EStorageType StorageType)=0

bool	PushData (FPushRequest Request, EStorageType StorageType)

bool	PushData (const FIoHash &Id, const FCompressedBuffer &Payload, const FString &Context, EStorageType StorageType)

virtual bool	PullData (TArrayView< FPullRequest > Requests)=0

FCompressedBuffer	PullData (const FIoHash &Id)

bool	PullData (FPullRequest Request)

virtual EQueryResult	QueryPayloadStatuses (TArrayView< const FIoHash > Ids, EStorageType StorageType, TArray< EPayloadStatus > &OutStatuses)=0

virtual FVirtualizationResult	TryVirtualizePackages (TConstArrayView< FString > PackagePaths, EVirtualizationOptions Options)=0

virtual FRehydrationResult	TryRehydratePackages (TConstArrayView< FString > PackagePaths, ERehydrationOptions Options)=0

virtual ERehydrationResult	TryRehydratePackages (TConstArrayView< FString > PackagePaths, uint64 PaddingAlignment, TArray< FText > &OutErrors, TArray< FSharedBuffer > &OutPackages, TArray< FRehydrationInfo > *OutInfo)=0

virtual void	DumpStats () const =0

virtual TArray< FBackendStats >	GetBackendStatistics () const =0

virtual FPayloadActivityInfo	GetSystemStatistics () const =0

virtual void	GatherAnalytics (TArray< FAnalyticsEventAttribute > &Attributes) const =0

virtual FOnNotification &	GetNotificationEvent ()=0

Static Public Member Functions
static CORE_API bool	IsInitialized ()

static CORE_API FName	GetSystemName ()

static CORE_API IVirtualizationSystem &	Get ()

Detailed Description

The base interface for the virtualization system. An Epic maintained version can be found in the Virtualization module. To implement your own, simply derived from this interface and then use the UE_REGISTER_VIRTUALIZATION_SYSTEM macro in the cpp to register it as an option. You can then set the config file option [Core.ContentVirtualization]SystemName=FooBar, where FooBar should be the SystemName parameter you used when registering with the macro.

Special Cases: SystemName=Off - This is the default set up and means a project will not use content virtualization Note that calling IVirtualizationSystem::Get() will still return a valid IVirtualizationSystem implementation, but all push and pull operations will result in failure and IsEnabled will always return false. SystemName=Default - This will cause the default Epic implementation to be used

See also: VirtualizationManager

Member Typedef Documentation

◆ FOnNotification

using UE::Virtualization::IVirtualizationSystem::FOnNotification = TTSMulticastDelegate<void(ENotification, const FIoHash&)>

Declare delegate for notifications

◆ GetPayloadActivityInfoFuncRef

using UE::Virtualization::IVirtualizationSystem::GetPayloadActivityInfoFuncRef = TFunctionRef<void(const FString& DebugName, const FString& ConfigName, const FPayloadActivityInfo& PayloadInfo)>

Member Enumeration Documentation

◆ ENotification

enum UE::Virtualization::IVirtualizationSystem::ENotification

Enumerator
PushBegunNotification
PushEndedNotification
PushFailedNotification
PullBegunNotification
PullEndedNotification
PullFailedNotification

Constructor & Destructor Documentation

◆ IVirtualizationSystem()

UE::Virtualization::IVirtualizationSystem::IVirtualizationSystem ( )

default

◆ ~IVirtualizationSystem()

virtual UE::Virtualization::IVirtualizationSystem::~IVirtualizationSystem ( )

virtualdefault

Member Function Documentation

◆ AllowSubmitIfVirtualizationFailed()

virtual bool UE::Virtualization::IVirtualizationSystem::AllowSubmitIfVirtualizationFailed ( ) const

pure virtual

Poll to see if the virtualization process failing when submitting a collection of files to source control should block that submit or allow it to continue.

NOTE: This is a bit of an odd ball option to be included in the VirtualizationSystem API but at the moment we don't really have a better place for it. This might be removed or replaced in future releases.

Returns: True if the calling code should continue with submitting files if the virtualization process failed. If it returns false then the calling code should prevent the submit.

Implemented in UE::Virtualization::FNullVirtualizationSystem.

◆ DumpStats()

virtual void UE::Virtualization::IVirtualizationSystem::DumpStats ( ) const

pure virtual

When called the system should write any performance stats that it has been gathering to the log file

Implemented in UE::Virtualization::FNullVirtualizationSystem.

◆ FilterPayload()

virtual EPayloadFilterReason UE::Virtualization::IVirtualizationSystem::FilterPayload ( const UObject * Owner ) const

pure virtual

Run checks to see if the payload can be virtualized or not.

Parameters

Owner The UObject that contains the payload, this can be nullptr if the payload is not owned by one

Returns: The reasons why the payload can not be virtualized, encoded as a bitfield of EPayloadFilterReason. This bitfield will be EPayloadFilterReason::None (0) if no reason was found.

Implemented in UE::Virtualization::FNullVirtualizationSystem.

◆ GatherAnalytics()

virtual void UE::Virtualization::IVirtualizationSystem::GatherAnalytics ( TArray< FAnalyticsEventAttribute > & Attributes ) const

pure virtual

Gather analytics data. Stats will only be collected if ENABLE_COOK_STATS is enabled.

Implemented in UE::Virtualization::FNullVirtualizationSystem.

◆ Get()

IVirtualizationSystem & UE::Virtualization::IVirtualizationSystem::Get ( )

static

Gain access to the current virtualization system active for the project. If the system has not yet been initialized then calling this method will initialize it.

◆ GetBackendStatistics()

virtual TArray< FBackendStats > UE::Virtualization::IVirtualizationSystem::GetBackendStatistics ( ) const

pure virtual

Access profiling info relating to payload activity per backend. Stats will only be collected if ENABLE_COOK_STATS is enabled.

Implemented in UE::Virtualization::FNullVirtualizationSystem.

◆ GetNotificationEvent()

virtual FOnNotification & UE::Virtualization::IVirtualizationSystem::GetNotificationEvent ( )

pure virtual

Implemented in UE::Virtualization::FNullVirtualizationSystem.

◆ GetSystemName()

FName UE::Virtualization::IVirtualizationSystem::GetSystemName ( )

static

Returns the name of the currently initialized system, will be NAME_None if initialization failed or the system is not enabled

◆ GetSystemStatistics()

virtual FPayloadActivityInfo UE::Virtualization::IVirtualizationSystem::GetSystemStatistics ( ) const

pure virtual

Access profiling info for all backends combined. Stats will only be collected if ENABLE_COOK_STATS is enabled.

Implemented in UE::Virtualization::FNullVirtualizationSystem.

◆ Initialize()

virtual bool UE::Virtualization::IVirtualizationSystem::Initialize ( const FInitParams & InitParams )

pure virtual

Initialize the system from the parameters given in the FInitParams structure. The system can only rely on the members of FInitParams to be valid for the duration of the method call, so if a system needs to retain information longer term then it should make it's own copy of the required data.

NOTE: Although it is relatively easy to access cached FConfigFiles, systems should use the one provided by InitParams to ensure that the correct settings are parsed.

Parameters

InitParam The parameters used to initialize the system

Returns: True if the system was initialized correctly, otherwise false. Note that if the method returns false then the system will be deleted and the default FNullVirtualizationSystem will be used instead.

Implemented in UE::Virtualization::FNullVirtualizationSystem.

◆ IsEnabled()

virtual bool UE::Virtualization::IVirtualizationSystem::IsEnabled ( ) const

pure virtual

Poll to see if content virtualization is enabled or not.

Implemented in UE::Virtualization::FNullVirtualizationSystem.

◆ IsInitialized()

bool UE::Virtualization::IVirtualizationSystem::IsInitialized ( )

static

Returns true if a virtualization system has been initialized and false if not

◆ IsPushingEnabled()

virtual bool UE::Virtualization::IVirtualizationSystem::IsPushingEnabled ( EStorageType StorageType ) const

pure virtual

Poll to see if pushing virtualized content to the given backend storage type is enabled or not.

Implemented in UE::Virtualization::FNullVirtualizationSystem.

◆ PullData() [1/3]

FCompressedBuffer UE::Virtualization::IVirtualizationSystem::PullData ( const FIoHash & Id )

inline

Pull a single payload from the virtualization backends.

Parameters

Id	The hash of the payload to pull

Returns: A valid buffer representing the payload if the pull was successful. An invalid buffer if the pull failed.

◆ PullData() [2/3]

bool UE::Virtualization::IVirtualizationSystem::PullData ( FPullRequest Request )

inline

Pull a single payload from the virtualization backends.

Parameters

Request A payload pull request.

See also: FPullRequest

Returns: True if the pull failed and the request will return a valid payload. False if the pull failed and the request will return an invalid payload

◆ PullData() [3/3]

virtual bool UE::Virtualization::IVirtualizationSystem::PullData ( TArrayView< FPullRequest > Requests )

pure virtual

Pull a number of payloads from the virtualization backends.

Parameters

Requests An array of payload pull requests.

See also: FPullRequest

Returns: True if the requests succeeded, false if one or more requests failed

Implemented in UE::Virtualization::FNullVirtualizationSystem.

◆ PushData() [1/3]

bool UE::Virtualization::IVirtualizationSystem::PushData	(	const FIoHash &	Id,
		const FCompressedBuffer &	Payload,
		const FString &	Context,
		EStorageType	StorageType
	)

inline

Push a payload to the virtualization backends.

Parameters

Id	The identifier of the payload being pushed.
Payload	The payload itself in FCompressedBuffer form, it is assumed that if the buffer is to be compressed that it will have been done by the caller.
Context	Context for the payload being submitted, typically the name from the UPackage that owns it.
StorageType	The type of storage to push the payload to, @See EStorageType for details.

Returns: When StorageType is EStorageType::Cache this will return true as long each payload ends up being stored in at least one of the cache backends. When StorageType is EStorageType::Persistent this will only return true if each payload endd up being stored in all of the backends. This is because the cache backends are not considered essential and it is not the end of the world if a payload is missing but the persistent backends must be reliable.

◆ PushData() [2/3]

bool UE::Virtualization::IVirtualizationSystem::PushData	(	FPushRequest	Request,
		EStorageType	StorageType
	)

inline

Push a payload to the virtualization backends.

Parameters

Request	A single push request
PackageContext	Context for the payload being submitted, typically the name from the UPackage that owns it.

Returns: When StorageType is EStorageType::Cache this will return true as long each payload ends up being stored in at least one of the cache backends. When StorageType is EStorageType::Persistent this will only return true if each payload endd up being stored in all of the backends. This is because the cache backends are not considered essential and it is not the end of the world if a payload is missing but the persistent backends must be reliable.

◆ PushData() [3/3]

virtual bool UE::Virtualization::IVirtualizationSystem::PushData	(	TArrayView< FPushRequest >	Requests,
		EStorageType	StorageType
	)

pure virtual

Push one or more payloads to a backend storage system. @See FPushRequest.

Parameters

Requests	A collection of one or more payload push requests
StorageType	The type of storage to push the payload to, @See EStorageType for details.

Returns: When StorageType is EStorageType::Cache this will return true as long each payload ends up being stored in at least one of the cache backends. When StorageType is EStorageType::Persistent this will only return true if each payload endd up being stored in all of the backends. This is because the cache backends are not considered essential and it is not the end of the world if a payload is missing but the persistent backends must be reliable.

Implemented in UE::Virtualization::FNullVirtualizationSystem.

◆ QueryPayloadStatuses()

virtual EQueryResult UE::Virtualization::IVirtualizationSystem::QueryPayloadStatuses	(	TArrayView< const FIoHash >	Ids,
		EStorageType	StorageType,
		TArray< EPayloadStatus > &	OutStatuses
	)

pure virtual

Query if a number of payloads exist or not in the given storage type.

Parameters

Ids	One or more payload identifiers to test
StorageType	The type of storage to push the payload to, @See EStorageType for details.
OutStatuses	[out] An array containing the results for each payload. @See FPayloadStatus If the operation succeeds the array will be resized to match the size of Ids.

Returns: True if the operation succeeded and the contents of OutStatuses is valid. False if errors were encountered in which case the contents of OutStatuses should be ignored.

Implemented in UE::Virtualization::FNullVirtualizationSystem.

◆ TryRehydratePackages() [1/2]

virtual FRehydrationResult UE::Virtualization::IVirtualizationSystem::TryRehydratePackages	(	TConstArrayView< FString >	PackagePaths,
		ERehydrationOptions	Options
	)

pure virtual

Runs the rehydration process on a set of packages. This involves downloading virtualized payloads and placing them back in the trailer of the given packages.

Parameters

PackagePaths	An array containing the absolute file paths of packages
Options	An enum bitfield containing various options for the process.

See also: EVirtualizationOptions

Parameters

OutResultInfo A struct that will contain info about the process.

See also: FVirtualizationResult

Returns: A ERehydrationResult enum with the status of the process. If the status indicates any sort of failure then OutResultInfo.Errors should contain at least one entry.

Implemented in UE::Virtualization::FNullVirtualizationSystem.

◆ TryRehydratePackages() [2/2]

virtual ERehydrationResult UE::Virtualization::IVirtualizationSystem::TryRehydratePackages	(	TConstArrayView< FString >	PackagePaths,
		uint64	PaddingAlignment,
		TArray< FText > &	OutErrors,
		TArray< FSharedBuffer > &	OutPackages,
		TArray< FRehydrationInfo > *	OutInfo
	)

pure virtual

Rehydrates a number of packages into memory buffers. Note that if a package does not require rehydration we will still return the package in a memory buffer but it will be the same as the package on disk.

Parameters

PackagePaths	An array containing the absolute file paths of packages.
PaddingAlignment	Byte alignment to pad each package buffer too, a value of 0 will result in the buffers being the same size as the packages
OutErrors	Any errors encountered while rehydration will be added here
OutPackages	The rehydrated packages as memory buffers. Each entry should match the corresponding entry in PackagePaths. This array is only guaranteed to be correct if the method returns ERehydrationResult::Success.
OutInfo	Information about the rehydration process, each entry should match the corresponding entry in PackagePaths assuming that the method returns ERehydrationResult::Success. This parameter is optional, if the information is not required then pass in nullptr to skip.

Returns: ERehydrationResult::Success if the rehydration suceeeds and OutPackages/OutInfocan be trued, otherwise it will return an error value.

See also: ERehydrationResult

Implemented in UE::Virtualization::FNullVirtualizationSystem.

◆ TryVirtualizePackages()

virtual FVirtualizationResult UE::Virtualization::IVirtualizationSystem::TryVirtualizePackages	(	TConstArrayView< FString >	PackagePaths,
		EVirtualizationOptions	Options
	)

pure virtual

Runs the virtualization process on a set of packages. All of the packages will be parsed and any found to be containing locally stored payloads will have them removed but before they are removed they will be pushed to persistent storage.

Note that if errors occur some or all of the payloads could still get pushed to persistent storage, usually if the errors occur when trying to remove the now virtualized payload from the packages on disk. In addition, if errors do occur when removing the virtualized payloads, some packages may be virtualized successfully. In any case the packages should still be usable and safe to checkin after the process has run, even with failure cases.

Parameters

PackagePaths	An array of file paths to packages that should be virtualized. If a path resolves to a file that is not a valid package then it will be silently skipped and will not be considered an error.
Options	An enum bitfield containing various options for the process.

See also: EVirtualizationOptions

Parameters

OutResultInfo A struct that will contain info about the process.

See also: FVirtualizationResult

Returns: A EVirtualizationResult enum with the status of the process. If the status is not EVirtualizationResult::Success then the parameter OutErrors should contain at least one entry.

Implemented in UE::Virtualization::FNullVirtualizationSystem.

The documentation for this class was generated from the following files:

Engine/Source/Runtime/Core/Public/Virtualization/VirtualizationSystem.h
Engine/Source/Runtime/Core/Private/Virtualization/VirtualizationSystem.cpp

Public Types

Public Member Functions

Static Public Member Functions

Detailed Description

Member Typedef Documentation

◆ FOnNotification

◆ GetPayloadActivityInfoFuncRef

Member Enumeration Documentation

◆ ENotification

Constructor & Destructor Documentation

◆ IVirtualizationSystem()

◆ ~IVirtualizationSystem()

Member Function Documentation

◆ AllowSubmitIfVirtualizationFailed()

◆ DumpStats()

◆ FilterPayload()

◆ GatherAnalytics()

◆ Get()

◆ GetBackendStatistics()

◆ GetNotificationEvent()

◆ GetSystemName()

◆ GetSystemStatistics()

◆ Initialize()

◆ IsEnabled()

◆ IsInitialized()

◆ IsPushingEnabled()

◆ PullData() [1/3]

◆ PullData() [2/3]

◆ PullData() [3/3]

◆ PushData() [1/3]

◆ PushData() [2/3]

◆ PushData() [3/3]

◆ QueryPayloadStatuses()

◆ TryRehydratePackages() [1/2]

◆ TryRehydratePackages() [2/2]

◆ TryVirtualizePackages()