5 Standard NodeClasses ToC Previous Next

5.2 Base NodeClass ToC Previous Next

5.2.9 RolePermissions ToC Previous Next

The optional RolePermissions Attribute specifies the Permissions that apply to a Node for all Roles which have access to the Node. The value of the Attribute is an array of RolePermissionType Structures (see Table 8).

Table 8 – RolePermissionType

Name Type Description
RolePermissionType Structure Specifies the Permissions for a Role
   roleId NodeId The NodeId of the Role Object.
   permissions PermissionType A mask specifying which Permissions are available to the Role.

Servers may allow administrators to write to the RolePermissions Attribute.

If not specified, the value of DefaultRolePermissions Property from the NamespaceMetadata Object associated with the Node shall be used instead. If the NamespaceMetadata Object does not define the Property or does not exist, then the Server should not publish any information about how it manages Permissions.

If a Server supports Permissions for a particular Namespace it shall add the DefaultRolePermissions Property to the NamespaceMetadata Object for that Namespace (see Figure 8). If a particular Node in the Namespace needs to override the default values, the Server adds the RolePermissions Attribute to the Node. The DefaultRolePermissions Property and RolePermissions Attribute shall only be readable by administrators. If a Server allows the Permissions to be changed these values shall be writeable. If the Server allows the Permissions to be overridden for a particular Node but does not currently have any Node Permissions configured, then the value of the Attribute shall be an empty array. If the administrator wishes to remove overridden Permissions, an empty array shall be written to this Attribute. Servers shall prevent Permissions from being changed in such a way as to render the Server inoperable.

If a Server publishes information about the Roles for a Namespace assigned to the current Session, it shall add the DefaultUserRolePermissions Property to the NamespaceMetadata Object for that Namespace. The value of this Property shall be a readonly list of Permissions for each Role assigned to the current Session. If a particular Node in the Namespace overrides the default RolePermissions the Server shall also override the DefaultUserRolePermissions by adding the UserRolePermissions Attribute to the Node. If the Server allows the Permissions to be overridden for a particular Node but does not currently have any Node Permissions configured, then the Server shall return the value of the DefaultUserRolePermissions Property for the Node Namespace.

If a Server implements a vendor specific Role Permission model for a Namespace, it shall not add the DefaultRolePermissions or DefaultUserRolePermissions Properties to the Namespace Metadata Object.

readme_files/image010.png Figure 8 – Permissions in the Address Space

Previous Next