.. _label-uc-service-remove:

Use-Case: Remove a Service
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.. Description of a use case
.. The description must be formulated as seen from system (not: actors)
.. Describes those changes an (outside) actor can notice
.. Short and abstract as possible, as long as necessary.
.. Each use case must have at least one actor involved
.. Each use case must have a trigger and a result


Short Description
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A service is removed from system.

Actor(s)
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Staff


Trigger(s)
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- Imports (removing existing data)
- Web form(s) submitted by authorized user.


Result(s)
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- The given service and all connected data (contracts, etc.) were
  removed from the system.
- All removed data is archived.


Incoming Data
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- Service ID

Outgoing Data
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- Message about service removal.
- Log message
- Archive entry.


Precondition(s)
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- Service ID must exist.
- Submitting user must be authorized to perform the operation.


Postcondition(s)
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Invariant(s)
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A service cannot be removed from the system while still contracts
connected to it exist in the system.


Essential Steps
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- System checks service ID validity.
- System checks whether any contracts created by the requested service
  are still in use in the system and cancels operation if so.
- Removed data is archived.
- System removes the given service.


Open Issues
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Remarks
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