encounter-compartment

encounter_compartment Validator Documentation

FHIR Compartment-Based Access Control for Encounter-Associated Resources

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Intent

The encounter_compartment validator restricts access to resources explicitly tied to a specific FHIR Encounter. This ensures users (e.g., clinicians, temporary roles) can only interact with data relevant to a time-bound clinical context, such as an emergency visit, surgery, or inpatient stay.

Key Use Cases:

• Emergency department staff accessing resources tied to an active patient encounter.
• Surgical teams updating records during an operation.
• Temporary access to lab results or imaging studies generated during a specific encounter.

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Key Features

1. Role Enforcement:
   • Validates that the client has the Encounter role (or a role mapped to an encounter context, e.g., Surgeon with encounter-scoped permissions).
2. Compartment Membership Check:
   • Confirms the requested resource type belongs to the FHIR Encounter compartment (e.g., Procedure, Observation, Encounter itself).
3. Reference Validation:
   • For create/update operations, ensures the resource references the encounter’s ID (e.g., Procedure.context.reference = Encounter/<id>).

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Validation Logic

Step	Action	Error If Failed
1	Check client_role is mapped to an encounter (e.g., Encounter role or a role with encounter context).	403 Forbidden (Invalid role/context)
2	Verify resource type is in the Encounter compartment.	403 Forbidden (Invalid compartment)
3	For write operations, validate encounter ID in relevant fields (e.g., context, encounter).	403 Forbidden (Reference mismatch)

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Example Configurations

1. Read Access to Procedures Linked to an Encounter

{
  "client_role": "Encounter",
  "entity_name": "Procedure",
  "operation": "read",
  "validator": "encounter_compartment"
}

Explanation: A user with encounter-scoped access can read Procedure resources only if Procedure.context.reference matches Encounter/<encounter_id>.

2. Create an Observation During an Inpatient Stay

{
  "client_role": "Encounter",
  "entity_name": "Observation",
  "operation": "create",
  "validator": "encounter_compartment"
}

Requirements: The Observation body must include:

"context": {
  "reference": "Encounter/<encounter_id>"
}

Otherwise, the request is denied.

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FHIR References

1. Encounter Compartment Definition:
   FHIR R4 Encounter Compartment (Official HL7 documentation).
2. Resource Examples:
   • Procedure.context
   • Encounter

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Use Case: Emergency Department Workflow

1. Temporary Access: A triage nurse with the Encounter role can:
   • View Observation resources (e.g., vital signs) tied to the active encounter.
   • Update Encounter.status to reflect patient progress.
2. Audit Compliance: All actions are automatically scoped to the encounter, simplifying audit trails.

Error Handling:

• A clinician attempting to access a DiagnosticReport outside the encounter’s time window receives 403 Forbidden.

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Assumptions & Notes

• If your system does not use a dedicated Encounter role, replace client_role with roles that inherit encounter context (e.g., EmergencyClinician with metadata linking to an encounter).
• The compartment is ephemeral: Access expires when the encounter is marked as finished.