CU Lookup

This process is used to look up information about controllable units to verify whether they are already registered in the system before initiating the following processes:

Why is CU lookup a necessary process?

To verify whether the unit is already registered in the system
to determine next step

This process retrieves the necessary information from FIS, to ensure that the service provider has sufficient data to determine the appropriate process to execute.

After a successful request, the service provider evaluates the returned CU data and decides the next step. If the CU is there, then the next step could be service provider switching or evaluation of the data. If the CU is not there, the service provider can create a new CU. This is further explained below.
To verify the link between the end user and the accounting point / CU

Before starting the CU registration or switching process, the service provider needs to verify the link between the end user and the accounting point / CU.
To prevent unauthorized use

To prevent unauthorized use, FIS requires the end user id from the service provider to allow them to access CU data.

If the accounting point or CU is already part of the system, this validation will be done based on existing data in FIS. Data for accounting points with CUs will always be synced from Elhub.

If, however, the service provider is requesting data for an accounting point that does not have any CUs registered in FIS, there will be a synchronous lookup towards Elhub to validate the accounting point end user relation. From then on, the accounting point will be part of the regular data sync from Elhub.

Prerequisites

Service provider has a consent from the end user to request data on the accounting point / CU.
Service provider knows the end user id and other key information about accounting point / CU.
CU ID provided from FIS must be used in service provider switching.

Request and response

The input to the controllable unit lookup contains three fields:

end user (EU) business identifier
accounting point (AP) business identifier
controllable unit (CU) business identifier

The request must contain EU and one of AP or CU. If that requirement is not met, or the format of the input is malformed, the request will be rejected with a 400 - Bad Request response.

If the request is valid, but the requested resource (CU or AP) does not exist, the response will be 404 - Not Found. If the requested resource exist, but the end user does not match the end user associated with the CU or AP, the response will be 403 - Forbidden.

Upon a successful request, the response will be 200 - Ok and contain the following fields:

Field	Abbr	Description
end_user	EU	Technical identifier for the end user.
accounting_point	AP	Information about the accounting point, including its identifier.
controllable_units	CU	A list of controllable units, if found. Each containing a list of technical resources.

The following table describes the possible combinations of input parameters and the expected response. The column Next action is just ment as a guide.

CU	AP	AP exists	CU(s) exists	EU matches	HTTP response	Response	Next action
Yes	No	❔	❌	❔	404 - Not found	ErrorMessage	Check request data
Yes	No	❔	✅	❌	403 - Forbidden	ErrorMessage	Check request data
Yes	No	❔	✅	✅	200 - Ok	EU, AP, CU(1)	Create contract
No	Yes	❌	❔	❔	404 - Not found	ErrorMessage	Check request data
No	Yes	✅	❔	❌	403 - Forbidden	ErrorMessage	Check request data
No	Yes	✅	❌	✅	200 - Ok	EU, AP, CU(0)	Create CU
No	Yes	✅	✅	✅	200 - Ok	EU, AP, CU(n)	Evaluate returned CUs

Sequence

Full Size | PlantUML description

Controllable Unit Lookup