HIM supports structuring information into different trees instead of bundling it all into one tree. This is likely to lead to that e. g. a server that manages a super domain of somewhat heterogeneous information will have that information represented by multiple trees. HIM enables this “forest of trees” to be accessed in a uniform manner by using the paths of the nodes of the trees to address the information contained in the trees. To support the server in managing this forest of trees, a HIM configuration tree provides a representation of the key parameters of this forest. The server may also share this configuration file on request from clients, in order for them to discover the information available by the forest.
The HIM model is not restricted to client/server models.
A file containing this configuration may have any name, but it is recommended that it contains version or date-time information. The file shall have the extension “.him”, which indicates that it is a HIM configuration file. Its format shall be YAML or any other text format that is compatible with YAML.
The configuration tree root node shall have the name “HIM”.
A server may share the information of this file with a client that wants to discover what information the server manages. It shall however not share the “local” metadata that is private to the server.
A HIM compliant server shall be able to read a HIM configuration file and from that access the forest of trees it defines.
A HIM compliant tree must follow the HIM rule set.
The project specifying this tree must also define the domain metadata for this tree,
and it may provide a public URL to a file containing the complete tree,
possible also multiple public URLs to renditions of the tree in different formats such as YAML, JSON, etc.
The creation of a HIM configuration file is the responsibility of the “manager” of the HIM server.
The following node types can be used in a configuration tree:
This example shows a forest consisting of three local trees, and a remote tree:
HIM:
type: branch
description: Contains the set of trees that are managed as one virtual domain.
VehicleData:
type: direct
domain: Vehicle.Car.ResourceData
version: X.Y.Z
local: file://<full-path-name>
public: https://himrepo.oem.com?instance=Vehicle.Car.ResourceData.X.Y.Z
description: ….
VehicleServices:
type: direct
domain: Vehicle.Car.ServiceData
version: X.Y.Z
local: file://<full-path-name>
public: https://himrepo.oem.com?instance=Vehicle.Car.ServiceData.X.Y.Z
description: ….
Types:
type: direct
domain: Vehicle.Car.TypeDefinition
version: X.Y.Z
local: file://<full-path-name>
public: https://himrepo.oem.com?instance=Vehicle.Car.DataType.X.Y.Z
description: ….
ChargingStationData:
type: proxy
domain:ChargingStation.Vehicle.ResourceData
version: X.Y.Z
public: https://himrepo.energyco.com?instance=ChargingStation.Vehicle.ResourceData.X.Y.Z
description: ….