OSID - osid.filing.FileSystemSession Service Interface Definition

Interface	osid.filing.FileSystemSession
Implements	`osid.OsidSession`
Description	This session defines methods for examining file systems. A `FileSystemSession` is associated with a directory that, unlike other catalogs, behaves as the current directory path for supplying relative path names. Absolute path names can be supplied to access any file or directory in the file system. This session defines the following views: comparative view: elements may be silently omitted or re-ordered plenary view: provides a complete result set or is an error condition federated directory view: searches include entries in directories of which this directory is an ancestor isolated directory view: lookups are restricted to entries in this directory only Generally, the comparative view should be used for most applications as it permits operation even if there is data out of sync. Some administrative applications may need to know whether it had retrieved an entire set of objects and may sacrifice some interoperability for the sake of precision using the plenary view.
Method	getDirectoryId
Description	Gets the `Id` of this directory.
Return	`osid.id.Id`		the `Id` of this directory
Compliance	`mandatory`		This method must be implemented.
Method	getDirectory
Description	Gets the directory associated with this session.
Return	`osid.filing.Directory`		the directory associated with this session
Errors	OPERATION_FAILED		unable to complete request
Errors	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	canLookupDirectoryEntries
Description	Tests if this user can perform entry lookups. A return of true does not guarantee successful authorization. A return of false indicates that it is known all methods in this session will result in a `PERMISSION_DENIED.` This is intended as a hint to an application that may opt not to offer lookup operations.
Return	`boolean`		`false` if lookup methods are not authorized, `true` otherwise
Compliance	`mandatory`		This method must be implemented.
Method	hasParentDirectory
Description	Tests if the directory associated with this session has a parent directory.
Return	`boolean`		`true` if a parent exists, `false` otherwise
Compliance	`mandatory`		This method is must be implemented.
Method	getParentDirectory
Description	Gets the parent of the directory associated with this session.
Return	`osid.filing.Directory`		the parent of the directory associated with this session
Errors	ILLEGAL_STATE		`hasParentDirectory()` is `false`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	useComparativeDirectoryView
Description	The returns from the lookup methods may omit or translate elements based on this session, such as authorization, and not result in an error. This view is used when greater interoperability is desired at the expense of precision.
Compliance	`mandatory`		This method is must be implemented.
Method	usePlenaryDirectoryView
Description	A complete view of the file or directory returns is desired. Methods will return what is requested or result in an error. This view is used when greater precision is desired at the expense of interoperability.
Compliance	`mandatory`		This method is must be implemented.
Method	useFederatedDirectoryView
Description	Federates the view for methods in this session. A federated view will include entries in directories which are children of this directory.
Compliance	`mandatory`		This method is must be implemented.
Method	useIsolatedDirectoryView
Description	Isolates the view for methods in this session. An isolated view restricts lookups to this directory only.
Compliance	`mandatory`		This method is must be implemented.
Method	exists
Description	Tests if a file, directory or alias name exists. In a federated view, the existence test is performed on this directory and any children of this directory. In an isolated view, the existence test is restrcited to this directory only.
Parameters	`string`	`name`	a file or directory name
Return	`boolean`		`true` if the name exists, `false` otherwise
Errors	NULL_ARGUMENT		`name` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method is must be implemented.
Method	isFile
Description	Tests if a name exists and is a file or an alias to a file. In a federated view, the exietence test is performed on this directory and any children of this directory. In an isolated view, the existence test is restrcited to this directory only.
Parameters	`string`	`name`	a file name
Return	`boolean`		`true` if the name is a file, `false` otherwise
Errors	NULL_ARGUMENT		`name` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method is must be implemented.
Method	isDirectory
Description	Tests if a name exists and is a directory or an alias to a directory. In a federated view, the exietence test is performed on this directory and any children of this directory. In an isolated view, the existence test is restrcited to this directory only.
Parameters	`string`	`name`	a file or directory name
Return	`boolean`		`true` if the path is a directory, `false` otherwise
Errors	NULL_ARGUMENT		`name` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method is must be implemented.
Method	isAlias
Description	Tests if a name exists and is an alias. In a federated view, the exietence test is performed on this directory and any children of this directory. In an isolated view, the existence test is restrcited to this directory only.
Parameters	`string`	`name`	a file or directory name
Return	`boolean`		`true` if the path is an alias, `false` otherwise
Errors	NULL_ARGUMENT		`name` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method is must be implemented.
Method	getFile
Description	Gets a specified file or alias to the file by its name in the current directory only. For federated views, use `getFilesByName().`
Parameters	`string`	`name`	the name to the file
Return	`osid.filing.File`		the file
Errors	NOT_FOUND		`name` is not found or is a directory
	NULL_ARGUMENT		`name` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	getFilesByName
Description	Gets a specified files and aliases to files for the given file name. In an isolated view, this method behaves like `getFile().` Is a federated view, this method returns a list of files by the same name in descendant directories. In plenary mode, the returned list contains all known files or an error results. Otherwise, the returned list may contain only those files that are accessible through this session.
Parameters	`string`	`name`	the name of the file
Return	`osid.filing.FileList`		the list of files of the given name
Errors	NULL_ARGUMENT		`name` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	getFiles
Description	Gets the list of files and aliases to files in this directory. In a federated view, this method returns all files in descendant directories. In plenary mode, the returned list contains all known files or an error results. Otherwise, the returned list may contain only those files that are accessible through this session.
Return	`osid.filing.FileList`		the list of files in this directory
Errors	OPERATION_FAILED		unable to complete request
Errors	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	getSubdirectory
Description	Gets a specified directory or alias to the directory by its name in the current directory only. For federated views, use `getDirectoriesByName().`
Parameters	`string`	`name`	the name of the directory
Return	`osid.filing.Directory`		the directory
Errors	NOT_FOUND		`name` is not found or is a file
	NULL_ARGUMENT		`name` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	getSubdirectoriesByName
Description	Gets a specified directories and aliases to directories for the given directory name. In an isolated view, this method behaves like `getDirectory().` Is a federated view, this method returns a list of directories by the same name in descedent directories. In plenary mode, the returned list contains all known files or an error results. Otherwise, the returned list may contain only those files that are accessible through this session.
Parameters	`string`	`name`	the name of the file
Return	`osid.filing.DirectoryList`		the list of files of the given name
Errors	NULL_ARGUMENT		`name` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	getSubdirectories
Description	Gets the list of directories and aliases to directories in this directory. In a federated view, this method returns all directories in descedent directories. In plenary mode, the returned list contains all known files or an error results. Otherwise, the returned list may contain only those files that are accessible through this session.
Return	`osid.filing.DirectoryList`		the list of directories in this directory
Errors	OPERATION_FAILED		unable to complete request
Errors	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.