OSID - osid.metering.MeterReadingSession Service Interface Definition

Interface	osid.metering.MeterReadingSession
Implements	`osid.OsidSession`
Description	This session is used to read meters. This reading session defines several views: comparative view: elements may be silently omitted or re-ordered plenary view: provides a complete result set or is an error condition federated utility view: includes meters in utilities which are children of this utility in the utility hierarchy isolated utility view: restricts lookups to this utility only
Method	getUtilityId
Description	Gets the `Utility` `Id` associated with this session.
Return	`osid.id.Id`		the `Utility Id` associated with this session
Compliance	`mandatory`		This method must be implemented.
Method	getUtility
Description	Gets the `Utility` associated with this session.
Return	`osid.metering.Utility`		the utility
Errors	OPERATION_FAILED		unable to complete request
Errors	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	canReadMeters
Description	Tests if this user can read meters. 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 metering operations.
Return	`boolean`		`false` if metering methods are not authorized, `true` otherwise
Compliance	`mandatory`		This method must be implemented.
Method	useComparativeMeterView
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	usePlenaryMeterView
Description	A complete view of the 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	useFederatedUtilityView
Description	Federates the view for methods in this session. A federated view will include meters in utilities which are children of this utility in the utility hierarchy.
Compliance	`mandatory`		This method is must be implemented.
Method	useIsolatedUtilityView
Description	Isolates the view for methods in this session. An isolated view restricts retrievals to this utility only.
Compliance	`mandatory`		This method is must be implemented.
Method	readMeter
Description	Gets the reading of the `Meter` specified by its `Id.` In plenary mode, the exact `Id` is found or a `NOT_FOUND` results. Otherwise, the returned `Meter` may have a different `Id` than requested, such as the case where a duplicate `Id` was assigned to a `Meter` and retained for compatibility.
Parameters	`osid.id.Id`	`meterId`	the `Id` of the `Meter` to retrieve
Parameters	`osid.id.Id`	`meteredObjectId`	the `Id` of the `Metered` to retrieve
Return	`osid.metering.Reading`		the meter reading
Errors	NOT_FOUND		no `Meter` found with the given `Id`
	NULL_ARGUMENT		`meterId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	readMeters
Description	Gets a `ReadingList` corresponding to the given `meterdId` and metered object list In plenary mode, the returned list contains all of the readings specified in the `Id` list, in the order of the list, including duplicates, or an error results if an `Id` in the supplied list is not found or inaccessible. Otherwise, inaccessible readings may be omitted from the list and may present the elements in any order including returning a unique set.
Parameters	`osid.id.Id`	`meterId`	the `Id` of the `Meter` to retrieve
Parameters	`osid.id.IdList`	`meteredObjectIds`	the `Ids` of the metered objects to retrieve
Return	`osid.metering.ReadingList`		the returned `Reading` list
Errors	NOT_FOUND		`meterId` or an `Id was` not found
	NULL_ARGUMENT		`meterI` d or `meteredObjectIds` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.