rustfs/crates/ecstore/src/bucket/lifecycle/README.md

ECStore Lifecycle Split Inventory

This directory still belongs to ECStore. It is not ready to become a standalone crate because lifecycle workers currently depend on ECStore runtime state, object IO, bucket metadata, replication scheduling, notification/audit sinks, and tier services.

Current Modules

Module	Current role	Split blocker
core.rs	Lifecycle rule model, action evaluation, object options, and transition/expiry decisions.	Uses ECStore object metadata types and compatibility DTO re-exports.
bucket_lifecycle_ops.rs	Worker orchestration, expiry, transition, stale multipart cleanup, audit, replication delete scheduling, and queue state.	Depends on ECStore, SetDisks, runtime globals, bucket metadata/versioning/replication, disk internals, event notification, and tier services.
evaluator.rs	Bucket lifecycle evaluation wrapper.	Reads object-lock and replication config from ECStore bucket modules.
rule.rs	Lifecycle rule filter helpers.	Uses lifecycle-local tagging boundary.
tier_delete_journal.rs	Remote tier delete journal persistence and recovery.	Uses lifecycle-local config persistence boundary, object IO contracts, metadata bucket paths, and ECStore.
tier_free_version_recovery.rs	Free-version recovery queue and object restoration path.	Depends on ECStore, object metadata, storage-api contracts, and lifecycle queue callbacks.
tier_last_day_stats.rs	Tier statistics helpers.	Pure data/stat logic, but still part of lifecycle worker reporting.
tier_sweeper.rs	Remote tier deletion worker and transition cleanup.	Depends on runtime sources, ECStore, tier journal persistence, signer-error handling, and lifecycle object options.
bucket_lifecycle_audit.rs	Lifecycle audit event source labels.	Must remain wired to lifecycle audit and notification sinks.

Required Contracts

Contract	Responsibility	Current dependency to remove
LifecycleObjectStore	Object stat, delete, transition, restore, multipart cleanup, and version-aware metadata operations.	Direct ECStore, SetDisks, disk, and object API access in worker paths.
LifecycleMetadataStore	Lifecycle, object-lock, replication, bucket versioning, and stale multipart metadata reads.	Direct bucket metadata, object-lock, versioning, and replication module imports.
LifecycleRuntime	Expiry state, transition state, tier config, deployment ID, local node name, queue metrics, cancellation, and worker sizing.	Direct runtime source/global access and process environment reads inside worker code.
LifecycleConfigStore	Persist, read, and remove lifecycle-owned journal/config objects.	Direct ECStore config persistence helper imports from worker paths.
LifecycleTagFilter	Decode object tag strings for lifecycle rule matching.	Direct bucket tagging helper imports from lifecycle rule paths.
LifecycleReplicationSink	Lifecycle-originated delete and version-purge replication scheduling.	Direct imports from bucket replication modules.
LifecycleAuditSink	Lifecycle audit and notification event emission.	Direct event notification service calls and audit-side effects from worker code.

Migration Rules

1. Do not move bucket/lifecycle into a new crate while any worker imports crate::store::ECStore, crate::set_disk::SetDisks, runtime globals, or bucket replication internals directly.
2. Extract pure contracts before runtime movement. The first code-bearing PR should introduce one contract boundary and keep the old ECStore call path.
3. Preserve lifecycle queue behavior, transition/expiry state, replication delete scheduling, notification/audit events, scanner-visible metrics, and stale multipart cleanup semantics.
4. Keep rustfs_ecstore::api::bucket::lifecycle compatibility until scanner, OBS, and test boundary files compile through replacement paths.
5. Verify each code-bearing step with focused lifecycle tests before attempting broad gates.

First Code-Bearing Step

Start with LifecycleRuntime or LifecycleAuditSink. Both can be introduced as narrow internal contracts while keeping the current ECStore worker behavior unchanged. Do not start with a crate move.

Current first boundary: runtime_boundary.rs centralizes lifecycle access to runtime state while preserving the existing ECStore-backed implementations. config_boundary.rs centralizes lifecycle-owned config object persistence for tier delete journal recovery while preserving the existing ECStore config store.