Component: Smrt.Retention

Canonical source: SmrtApps/src/Smrt.Retention/README.md (mirrored below)

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Smrt.Retention

Enterprise-grade retention and legal hold primitives shared by Supervisor, Storage Guard, HubWindow, and Support Bundle components.

Overview and responsibilities

• Defines canonical models for retention policies, legal holds, and verification evidence.
• Provides validation + normalization helpers so every host enforces the same business rules.
• Provides canonical path resolution helpers for config + evidence artifacts.

Public surface / entry points

• Not documented yet.

Dependencies and integrations

• Consumed by Supervisor, Storage Guard, HubWindow, and Support Bundle.

Configuration and operational data

• Persists retention config under %ProgramData%/SmrtHub/Config/retention/ via SmrtHub.Config.ConfigJson with atomic writes.
• Evidence path resolution is provided via RetentionPaths (callers should not hard-code directories).

Observability and diagnostics

• Not documented yet.

Testing and validation

• Unit tests live in SmrtApps/tests/Smrt.Retention.Tests.

Support Bundle

• Retention config and evidence artifacts are exported via Support Bundle (see Retention Capability/SubSystem docs).

Related docs

• Retention Subsystem (contracts and invariants): README.Files/Subsystems/Retention/README.md
• Retention Capability (end-to-end flow): README.Files/Capabilities/Retention/README.md
• Retention & Legal Hold Plan (Phase 3): README.Files/System/Plans/SmrtHub-Retention-and-LegalHold.README.md

Related platform docs

• Retention Subsystem (contracts and invariants): README.Files/Subsystems/Retention/README.md
• Retention Capability (end-to-end flow): README.Files/Capabilities/Retention/README.md
• Retention & Legal Hold Plan (Phase 3): README.Files/System/Plans/SmrtHub-Retention-and-LegalHold.README.md

Responsibilities

• Define canonical models for retention policies, legal holds, and verification evidence.
• Provide validation + normalization helpers so every host enforces the same business rules (slug uniqueness, retention windows, legal-hold overrides).
• Handle persistence via SmrtHub.Config.ConfigJson with atomic writes under %ProgramData%/SmrtHub/Config/retention/ (falling back to %LocalAppData% on developer machines).
• Surface deterministic helper APIs for resolving config/evidence paths so Storage Guard workers, Supervisor CLI, and Support Bundle providers never diverge.

Key Files

File	Purpose
Models/RetentionPolicy.cs	DTO representing per-provider retention rules (days, free-space floors, max artifact size).
Models/LegalHold.cs	Captures hold metadata (scope, owner, reason, expiry).
Models/RetentionConfiguration.cs	Aggregate of policies + holds with helper methods to resolve effective policies.
Models/RetentionEvidence.cs	Output contract for scheduled verification jobs/signatures.
Storage/RetentionPaths.cs	Canonical path resolution for config + evidence artifacts.
Storage/RetentionConfigurationStore.cs	Atomic load/save helper that exposes PolicyPath/LegalHoldPath and enforces validation via Validation/RetentionConfigurationValidator.cs.
Validation/RetentionConfigurationValidator.cs	Enforces enterprise guardrails (retention days, slug uniqueness, hold scope semantics).
Validation/RetentionValidationException.cs	Exception that carriers validation issues back to callers for UI/CLI display.

Usage Notes

• Always run configurations through RetentionConfigurationStore.Save so validation occurs before the files hit disk.
• RetentionPaths exposes helper methods for policy, hold, evidence, and health files; do not hard-code directories.
• The library does not schedule jobs or mutate provider data—callers handle orchestration and logging.

Tests

Unit tests live in SmrtApps/tests/Smrt.Retention.Tests. They cover validation, normalization, and round-trip persistence to ensure we don't regress path handling.