OSID - osid.topology.GraphHierarchySession Service Interface Definition

Interface	osid.topology.GraphHierarchySession
Implements	`osid.OsidSession`
Description	This session defines methods for traversing a hierarchy of `Graph` objects. Each node in the hierarchy is a unique `Graph.` The hierarchy may be traversed recursively to establish the tree structure through `getParentGraphs()` and `getChildGraphs().` To relate these `Ids` to another OSID, `getGraphNodes()` can be used for retrievals that can be used for bulk lookups in other OSIDs. Any `Graph` available in the Topology OSID is known to this hierarchy but does not appear in the hierarchy traversal until added as a root node or a child of another node. A user may not be authorized to traverse the entire hierarchy. Parts of the hierarchy may be made invisible through omission from the returns of `getParentGraphs()` or `getChildGraphs()` in lieu of a `PERMISSION_DENIED` error that may disrupt the traversal through authorized pathways. This session defines views that offer differing behaviors when retrieving multiple objects. comparative graph view: graph elements may be silently omitted or re-ordered plenary graph view: provides a complete set or is an error condition
Method	getGraphHierarchyId
Description	Gets the hierarchy `Id` associated with this session.
Return	`osid.id.Id`		the hierarchy `Id` associated with this session
Compliance	`mandatory`		This method must be implemented.
Method	getGraphHierarchy
Description	Gets the hierarchy associated with this session.
Return	`osid.hierarchy.Hierarchy`		the hierarchy associated with this session
Errors	OPERATION_FAILED		unable to complete request
Errors	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	canAccessGraphHierarchy
Description	Tests if this user can perform hierarchy queries. 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 hierarchy traversal methods are not authorized, `true` otherwise
Compliance	`mandatory`		This method must be implemented.
Method	useComparativeGraphView
Description	The returns from the graph 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	usePlenaryGraphView
Description	A complete view of the `Graphs` 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	getRootGraphIds
Description	Gets the root graph `Ids` in this hierarchy.
Return	`osid.id.IdList`		the root catalog `Ids`
Errors	OPERATION_FAILED		unable to complete request
Errors	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	getRootGraphs
Description	Gets the root graph in the graph hierarchy. A node with no parents is an orphan. While all graph `Ids` are known to the hierarchy, an orphan does not appear in the hierarchy unless explicitly added as a root node or child of another node.
Return	`osid.topology.GraphList`		the root graphs
Errors	OPERATION_FAILED		unable to complete request
Errors	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method is must be implemented.
Method	hasParentGraphs
Description	Tests if the `Graph` has any parents.
Parameters	`osid.id.Id`	`graphId`	a catalog `Id`
Return	`boolean`		`true` if the catalog has parents, f `alse` otherwise
Errors	NOT_FOUND		`graphId` is not found
	NULL_ARGUMENT		`graphId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	isParentOfGraph
Description	Tests if an `Id` is a direct parent of graph.
Parameters	`osid.id.Id`	`id`	an `Id`
Parameters	`osid.id.Id`	`graphId`	the `Id` of a graph
Return	`boolean`		`true` if this `id` is a parent of `graphId,` f `alse` otherwise
Errors	NOT_FOUND		`graphId` is not found
	NULL_ARGUMENT		`id` or `graphId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Provider Notes	If `id` not found return `false.`
Method	getParentGraphIds
Description	Gets the parent `Ids` of the given graph.
Parameters	`osid.id.Id`	`graphId`	a catalog `Id`
Return	`osid.id.IdList`		the parent `Ids` of the graph
Errors	NOT_FOUND		`graphId` is not found
	NULL_ARGUMENT		`graphId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	getParentGraphs
Description	Gets the parents of the given graph.
Parameters	`osid.id.Id`	`graphId`	the `Id` to query
Return	`osid.topology.GraphList`		the parents of the graph
Errors	NOT_FOUND		`graphId` not found
	NULL_ARGUMENT		`graphId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	isAncestorOfGraph
Description	Tests if an `Id` is an ancestor of a graph.
Parameters	`osid.id.Id`	`id`	an `Id`
Parameters	`osid.id.Id`	`graphId`	the `Id` of a catalog
Return	`boolean`		`tru` e if this `id` is an ancestor of `graphId,` `false` otherwise
Errors	NOT_FOUND		`graphId` not found
	NULL_ARGUMENT		`graphId` or `id` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Provider Notes	If `id` not found return `false.`
Method	hasChildGraphs
Description	Tests if a graph has any children.
Parameters	`osid.id.Id`	`graphId`	a graph `Id`
Return	`boolean`		`true` if the `graphId` has children, `false` otherwise
Errors	NOT_FOUND		`graphId` not found
	NULL_ARGUMENT		`graphId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	isChildOfGraph
Description	Tests if a graph is a direct child of another.
Parameters	`osid.id.Id`	`id`	an `Id`
Parameters	`osid.id.Id`	`graphId`	the `Id` of a graph
Return	`boolean`		`true` if the `id` is a child of `graphId,` `false` otherwise
Errors	NOT_FOUND		`graphId` not found
	NULL_ARGUMENT		`id` or `graphId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Provider Notes	If `id` not found return `false.`
Method	getChildGraphIds
Description	Gets the child `Ids` of the given graph.
Parameters	`osid.id.Id`	`graphId`	the `Id` to query
Return	`osid.id.IdList`		the children of the catalog
Errors	NOT_FOUND		`graphId` not found
	NULL_ARGUMENT		`graphId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	getChildGraphs
Description	Gets the children of the given graph.
Parameters	`osid.id.Id`	`graphId`	the `Id` to query
Return	`osid.topology.GraphList`		the children of the graph
Errors	NOT_FOUND		`graphId` not found
	NULL_ARGUMENT		`graphId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	isDescendantOfGraph
Description	Tests if an `Id` is a descendant of a graph.
Parameters	`osid.id.Id`	`id`	an `Id`
Parameters	`osid.id.Id`	`graphId`	the `Id` of a catalog
Return	`boolean`		`true` if the `id` is a descendant of the `graphId,` `false` otherwise
Errors	NOT_FOUND		`graphId` not found
	NULL_ARGUMENT		`id` or `graphId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Provider Notes	If `id` is not found return `false.`
Method	getGraphNodeIds
Description	Gets a portion of the hierarchy for the given graph.
Parameters	`osid.id.Id`	`graphId`	the `Id` to query
	`cardinal`	`ancestorLevels`	the maximum number of ancestor levels to include. A value of 0 returns no parents in the node.
	`cardinal`	`descendantLevels`	the maximum number of descendant levels to include. A value of 0 returns no children in the node.
	`boolean`	`includeSiblings`	`true` to include the siblings of the given node, `false` to omit the siblings
Return	`osid.hierarchy.Node`		a catalog node
Errors	NOT_FOUND		`graphId` not found
	NULL_ARGUMENT		`graphId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	getGraphNodes
Description	Gets a portion of the hierarchy for the given graph.
Parameters	`osid.id.Id`	`graphId`	the `Id` to query
	`cardinal`	`ancestorLevels`	the maximum number of ancestor levels to include. A value of 0 returns no parents in the node.
	`cardinal`	`descendantLevels`	the maximum number of descendant levels to include. A value of 0 returns no children in the node.
	`boolean`	`includeSiblings`	`true` to include the siblings of the given node, `false` to omit the siblings
Return	`osid.topology.GraphNode`		a graph node
Errors	NOT_FOUND		`graphId` not found
	NULL_ARGUMENT		`graphId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.