vtkCacheManager Class Reference

Manages the on-disk remote cache used by MRML storage. More...

#include <Libs/MRML/Core/vtkCacheManager.h>

Inheritance diagram for vtkCacheManager:

Collaboration diagram for vtkCacheManager:

Classes
struct	CacheEntry
	Describes a top-level item (file or folder) in the cache directory. More...

Public Types
enum	{ NoCachedFile = 0 , OldCachedFile , CachedFile }
	Currently these are not used. More...
enum	{   InsufficientFreeBufferEvent = 21000 , CacheLimitExceededEvent , CacheDeleteEvent , CacheDirtyEvent ,   CacheClearEvent }
typedef vtkObject	Superclass

Public Member Functions
virtual bool	CachedFileExists (const char *filename)
virtual bool	CachedFileExists (const std::string &filename)
bool	ClearCache ()
	Removes all files from the cachedir.
bool	CreateSentinelFile () const
	Creates the sentinel file in the current cache directory.
bool	CreateSentinelFileInDirectory (const std::string &directoryPath) const
	Creates the sentinel file in the specified directory.
void	DeleteFromCache (const char *target)
void	DeleteFromCache (const std::string &filename)
std::string	EncodeURI (const char *uri)
std::string	FindCachedFile (const char *target, const char *dirname)
std::vector< std::string >	GetCachedFiles () const
std::vector< std::string >	GetCachedFilesInDirectory (const std::string &directoryPath)
std::vector< CacheEntry >	GetCacheEntries () const
virtual const char *	GetClassName ()
float	GetCurrentCacheSize ()
	Current cache size in MB. Updated by UpdateCacheInformation().
virtual int	GetEnableForceRedownload ()
const char *	GetFileFromURIMap (const char *uri)
std::string	GetFilenameFromURI (const char *uri)
std::string	GetFilenameFromURI (const std::string &uri)
float	GetFreeCacheSpaceRemaining ()
	Returns the amount of free space remaining in the cache directory, in MB. Updated by UpdateCacheInformation().
virtual int	GetInsufficientFreeBufferNotificationFlag ()
const char *	GetRemoteCacheDirectory ()
	Returns the name of the directory to use for local file caching.
virtual int	GetRemoteCacheLimit ()
	Cache size limit in MB.
std::string	GetSentinelFileName () const
	Sentinel file name used to identify cache directories where file deletion is allowed.
bool	HasSentinelFile () const
	True if the sentinel file exists in the current cache directory.
bool	HasSentinelFileInDirectory (const std::string &directoryPath) const
	True if the sentinel file exists in the specified directory.
virtual int	IsA (const char *type)
bool	IsDirectoryEmpty (const std::string &directoryPath) const
	Returns true if the specified directory is empty.
virtual bool	IsLocalReference (const char *uri)
	Looks for a 'file://' in the URI and if present, returns true.
virtual bool	IsRemoteReference (const char *uri)
virtual bool	LocalFileExists (const char *uri)
void	MapFileToURI (const char *uri, const char *fname)
void	PrintSelf (ostream &os, vtkIndent indent) override
bool	PruneCache ()
virtual void	SetEnableForceRedownload (int)
virtual void	SetInsufficientFreeBufferNotificationFlag (int)
void	SetMRMLScene (vtkMRMLScene *scene)
virtual void	SetRemoteCacheDirectory (const char *dir)
virtual void	SetRemoteCacheDirectory (const std::string &dir)
virtual void	SetRemoteCacheLimit (int)
void	UpdateCacheInformation ()
	Called when a file is loaded or removed from the cache.

Static Public Member Functions
static int	IsTypeOf (const char *type)
static vtkCacheManager *	New ()
	The Usual vtk class functions.
static vtkCacheManager *	SafeDownCast (vtkObject *o)

Protected Member Functions
void	operator= (const vtkCacheManager &)
	vtkCacheManager ()
	vtkCacheManager (const vtkCacheManager &)
	~vtkCacheManager () override

Protected Attributes
vtkCallbackCommand *	CallbackCommand
	Holder for callback.

Detailed Description

Manages the on-disk remote cache used by MRML storage.

The class manages a folder that stores temporary files, mostly used for local caching of remote data.

The cache folder needs to be cleaned when the maximum size is reached. To prevent accidental deletion of non-cache user data, the class uses a "sentinel file" mechanism. Presence of a sentinel file (.slicer-cache) in the folder marks it as owned by the cache manager, allowing the cache manager to delete files in it. Deletion is strictly limited to files within the cache directory (symlinks are resolved and file is only deleted if the canonicalized path is inside the cache root folder).

Definition at line 32 of file vtkCacheManager.h.

Member Typedef Documentation

Superclass

typedef vtkObject vtkCacheManager::Superclass

Definition at line 37 of file vtkCacheManager.h.

Member Enumeration Documentation

anonymous enum

anonymous enum

Currently these are not used.

Enumerator
NoCachedFile
OldCachedFile
CachedFile

Definition at line 172 of file vtkCacheManager.h.

anonymous enum

anonymous enum

Enumerator
InsufficientFreeBufferEvent
CacheLimitExceededEvent
CacheDeleteEvent
CacheDirtyEvent
CacheClearEvent

Definition at line 179 of file vtkCacheManager.h.

Constructor & Destructor Documentation

vtkCacheManager() [1/2]

vtkCacheManager::vtkCacheManager ( )

protected

~vtkCacheManager()

vtkCacheManager::~vtkCacheManager ( )

overrideprotected

vtkCacheManager() [2/2]

vtkCacheManager::vtkCacheManager ( const vtkCacheManager & )

protected

Member Function Documentation

CachedFileExists() [1/2]

virtual bool vtkCacheManager::CachedFileExists ( const char * filename )

virtual

Checks to see if the The URI provided exists on disk. If not, it appends the Remote Cache Directory path and checks again, in case no path was provided. If neither exists, returns false. If one exists, returns true.

CachedFileExists() [2/2]

virtual bool vtkCacheManager::CachedFileExists ( const std::string & filename )

virtual

ClearCache()

bool vtkCacheManager::ClearCache

(

)

Removes all files from the cachedir.

CreateSentinelFile()

bool vtkCacheManager::CreateSentinelFile

(

)

const

Creates the sentinel file in the current cache directory.

CreateSentinelFileInDirectory()

bool vtkCacheManager::CreateSentinelFileInDirectory

(

const std::string &

directoryPath

)

const

Creates the sentinel file in the specified directory.

DeleteFromCache() [1/2]

void vtkCacheManager::DeleteFromCache

(

const char *

target

)

Remove a target directory or file from the cache folder. If the target is a directory, it will be removed recursively. Before deletion, any MRML nodes that hold the URI as a reference will be marked as "modified since read".

DeleteFromCache() [2/2]

void vtkCacheManager::DeleteFromCache

(

const std::string &

filename

)

EncodeURI()

std::string vtkCacheManager::EncodeURI

(

const char *

uri

)

FindCachedFile()

std::string vtkCacheManager::FindCachedFile	(	const char *	target,
		const char *	dirname )

Takes a filename and a dirname (usually called with the RemoteCachedDirectory) and returns the full path of the filename if it exists under the dirname.

GetCachedFiles()

std::vector< std::string > vtkCacheManager::GetCachedFiles

(

)

const

Get list of cached files. Updated by UpdateCacheInformation(). Get files in the folder, ordered by modification time from newest to oldest. Does not include the sentinel file.

GetCachedFilesInDirectory()

std::vector< std::string > vtkCacheManager::GetCachedFilesInDirectory

(

const std::string &

directoryPath

)

Get files in the folder, ordered by modification time from newest to oldest. Does not include the sentinel file.

GetCacheEntries()

std::vector< CacheEntry > vtkCacheManager::GetCacheEntries

(

)

const

Returns one CacheEntry per top-level item in the cache directory. Updated by UpdateCacheInformation() Entries are sorted newest-first (descending ModifiedTime). Does not include the sentinel file. CacheEntry::ExceedsCacheSize is set for entries that PruneCache() would evict.

GetClassName()

virtual const char * vtkCacheManager::GetClassName ( )

virtual

GetCurrentCacheSize()

float vtkCacheManager::GetCurrentCacheSize

(

)

Current cache size in MB. Updated by UpdateCacheInformation().

GetEnableForceRedownload()

virtual int vtkCacheManager::GetEnableForceRedownload ( )

virtual

GetFileFromURIMap()

const char * vtkCacheManager::GetFileFromURIMap

(

const char *

uri

)

GetFilenameFromURI() [1/2]

std::string vtkCacheManager::GetFilenameFromURI

(

const char *

uri

)

Extracts the filename from the URI and prepends the Remote Cache Directory path to it. Returns the full path. NOTE: this method looks at a filename's extension and if appended version numbers have been added, it attempts to strip them out of the extension and add them to the filenamebase. So filename.nrrd_010 would become filename.nrrd. This will cause problems for any file type with an '_' in its extension.

GetFilenameFromURI() [2/2]

std::string vtkCacheManager::GetFilenameFromURI

(

const std::string &

uri

)

GetFreeCacheSpaceRemaining()

float vtkCacheManager::GetFreeCacheSpaceRemaining

(

)

Returns the amount of free space remaining in the cache directory, in MB. Updated by UpdateCacheInformation().

GetInsufficientFreeBufferNotificationFlag()

virtual int vtkCacheManager::GetInsufficientFreeBufferNotificationFlag ( )

virtual

GetRemoteCacheDirectory()

const char * vtkCacheManager::GetRemoteCacheDirectory

(

)

Returns the name of the directory to use for local file caching.

GetRemoteCacheLimit()

virtual int vtkCacheManager::GetRemoteCacheLimit ( )

virtual

Cache size limit in MB.

GetSentinelFileName()

std::string vtkCacheManager::GetSentinelFileName

(

)

const

Sentinel file name used to identify cache directories where file deletion is allowed.

HasSentinelFile()

bool vtkCacheManager::HasSentinelFile

(

)

const

True if the sentinel file exists in the current cache directory.

HasSentinelFileInDirectory()

bool vtkCacheManager::HasSentinelFileInDirectory

(

const std::string &

directoryPath

)

const

True if the sentinel file exists in the specified directory.

IsA()

virtual int vtkCacheManager::IsA ( const char * type )

virtual

IsDirectoryEmpty()

bool vtkCacheManager::IsDirectoryEmpty

(

const std::string &

directoryPath

)

const

Returns true if the specified directory is empty.

IsLocalReference()

virtual bool vtkCacheManager::IsLocalReference ( const char * uri )

virtual

Looks for a 'file://' in the URI and if present, returns true.

IsRemoteReference()

virtual bool vtkCacheManager::IsRemoteReference ( const char * uri )

virtual

Checks to see if a URI appears to point to remote location and returns true if so. Looks for a '://' and if present, checks to see if the prefix is 'file'. If not 'file' but the thing:/// pattern exists, then returns true.

IsTypeOf()

static int vtkCacheManager::IsTypeOf ( const char * type )

static

LocalFileExists()

virtual bool vtkCacheManager::LocalFileExists ( const char * uri )

virtual

Checks to see if a URI is a file on disk and returns true if so. Strips off a file:/// prefix if present, and expects an absolute path.

MapFileToURI()

void vtkCacheManager::MapFileToURI	(	const char *	uri,
		const char *	fname )

New()

static vtkCacheManager * vtkCacheManager::New ( )

static

The Usual vtk class functions.

operator=()

void vtkCacheManager::operator= ( const vtkCacheManager & )

protected

PrintSelf()

void vtkCacheManager::PrintSelf ( ostream & os, vtkIndent indent )

override

PruneCache()

bool vtkCacheManager::PruneCache

(

)

Delete oldest files until on-disk cache usage fits within RemoteCacheLimit. Returns true on success and false on failure.

SafeDownCast()

static vtkCacheManager * vtkCacheManager::SafeDownCast ( vtkObject * o )

static

SetEnableForceRedownload()

virtual void vtkCacheManager::SetEnableForceRedownload ( int )

virtual

SetInsufficientFreeBufferNotificationFlag()

virtual void vtkCacheManager::SetInsufficientFreeBufferNotificationFlag ( int )

virtual

SetMRMLScene()

void vtkCacheManager::SetMRMLScene ( vtkMRMLScene * scene )

inline

Definition at line 40 of file vtkCacheManager.h.

SetRemoteCacheDirectory() [1/2]

virtual void vtkCacheManager::SetRemoteCacheDirectory ( const char * dir )

virtual

Sets the name of the directory to use for local file caching Does some checking to make sure this is a valid directory on the local system. Makes sure there's NO "/" at the end of the string, or kwsys/SystemTools will not see as a valid dir.

SetRemoteCacheDirectory() [2/2]

virtual void vtkCacheManager::SetRemoteCacheDirectory ( const std::string & dir )

inlinevirtual

Definition at line 48 of file vtkCacheManager.h.

SetRemoteCacheLimit()

virtual void vtkCacheManager::SetRemoteCacheLimit ( int )

virtual

UpdateCacheInformation()

void vtkCacheManager::UpdateCacheInformation

(

)

Called when a file is loaded or removed from the cache.

Member Data Documentation

CallbackCommand

vtkCallbackCommand* vtkCacheManager::CallbackCommand

protected

Holder for callback.

Definition at line 234 of file vtkCacheManager.h.

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

• Libs/MRML/Core/vtkCacheManager.h