TenantAtlas/specs/205-compare-job-cleanup/data-model.md

Data Model: Compare Job Legacy Drift Path Cleanup

Overview

This feature introduces no new top-level persisted entity and no new runtime or product-facing contract. It removes an obsolete implementation branch from CompareBaselineToTenantJob and preserves the existing persisted truths and compare contracts that already drive the live strategy-based compare flow. The OpenAPI document in contracts/ is a planning-only logical artifact that records invariants for this cleanup; it does not define a new runtime integration surface.

Existing Persisted Truth Reused Without Change

Workspace-owned baseline truth

• baseline_profiles
• baseline_snapshots
• baseline_snapshot_items
• Canonical baseline scope payload already stored in profile and run context

These remain the baseline reference truth that compare reads.

Tenant-owned current-state and operational truth

• inventory_items
• operation_runs for baseline_compare
• findings written by the baseline compare lifecycle
• existing run-context JSON such as baseline_compare, findings, and result

These remain the long-lived operational truths written or consumed by compare.

Existing evidence inputs reused without change

• policy-version content evidence
• inventory meta evidence
• current-state hash resolution
• coverage and gap context already recorded in the compare run

Spec 205 changes none of these inputs; it only removes a dead alternate computation path.

Existing Internal Contracts Preserved

Compare orchestration path

The live orchestration path remains:

1. CompareBaselineToTenantJob::handle()
2. CompareStrategyRegistry::select(...)
3. CompareStrategyRegistry::resolve(...)
4. strategy->compare(...)
5. normalizeStrategySubjectResults(...)
6. finding upsert, summary aggregation, gap handling, and run completion

No new branch, fallback path, or second engine is introduced.

CompareStrategySelection

Existing selection metadata remains unchanged and continues to be written into the compare run context.

Field	Purpose	Change in Spec 205
selection_state	Supported vs unsupported strategy state	unchanged
strategy_key	Active compare strategy family	unchanged
diagnostics	Secondary strategy selection detail	unchanged

CompareOrchestrationContext

Existing strategy input context remains unchanged.

Field	Purpose	Change in Spec 205
workspace_id	Workspace scope for compare run	unchanged
tenant_id	Tenant scope for compare run	unchanged
baseline_profile_id	Baseline profile reference	unchanged
baseline_snapshot_id	Snapshot reference	unchanged
operation_run_id	Run identity	unchanged
normalized_scope	Canonical scope payload	unchanged
coverage_context	Coverage and unsupported-type context	unchanged

CompareSubjectResult and CompareFindingCandidate

Existing per-subject compare results and finding projection contracts remain unchanged.

Contract	Purpose	Change in Spec 205
CompareSubjectResult	Strategy-owned per-subject compare outcome	unchanged
CompareFindingCandidate	Strategy-neutral finding mutation payload	unchanged

OperationRun compare context

The compare run continues to record current strategy, evidence coverage, gap counts, fidelity, reason translation, and result summaries inside the existing context structure. Spec 205 does not add, remove, or rename run-context fields.

Finding lifecycle output

Finding severity, change type, recurrence key, evidence fidelity, timestamps, reopen behavior, and auto-close behavior remain unchanged. Spec 205 only preserves the live path that already feeds these outputs.

Deleted Internal Cluster

Current repository inspection confirms one dead implementation cluster anchored by computeDrift() inside CompareBaselineToTenantJob, plus exclusive helpers clustered beneath it. The current candidate delete set includes:

• computeDrift()
• effectiveBaselineHash()
• resolveBaselinePolicyVersionId()
• selectSummaryKind()
• buildDriftEvidenceContract()
• buildRoleDefinitionEvidencePayload()
• resolveRoleDefinitionVersion()
• fallbackRoleDefinitionNormalized()
• roleDefinitionChangedKeys()
• roleDefinitionPermissionKeys()
• resolveRoleDefinitionDiff()
• severityForRoleDefinitionDiff()

The final delete list is confirmed by call-graph inspection during implementation. Any method still used by the live orchestration path remains out of scope.

Relationships

• One baseline_compare run selects one supported strategy.
• One selected strategy processes many compare subjects.
• One CompareSubjectResult may yield zero or one CompareFindingCandidate.
• Existing finding and summary writers consume the strategy result contracts directly.
• The legacy drift cluster is not part of any required runtime relationship after Spec 203 and is therefore removed.

Validation Rules

1. CompareBaselineToTenantJob::handle() must not call computeDrift() or any helper used exclusively by that legacy path.
2. Compare execution must continue to run through strategy selection, strategy resolution, and strategy->compare(...).
3. Existing OperationRun status, outcome, summary-count, and context semantics must remain unchanged.
4. Existing finding lifecycle behavior must remain driven by normalized strategy subject results.
5. No new persistence, contract, or state family may be introduced as part of the cleanup.

State Transitions

No new state transition is introduced.

Existing compare run transitions such as queued -> running -> completed or blocked remain unchanged, and finding lifecycle transitions remain governed by the current writers and services.