Module migrate 

gtc op env migrate-dev <target> (A4b of plans/next-gen-deployment.md).

Preflight-gated, one-shot migration of a legacy dev environment to the A4 bootstrap target (typically local). Two verbs:

• --check — runs every registered MigrationScanner and emits a MigrateDevReport. clean is true iff no scanner reported a FindingSeverity::Blocking finding.
• --apply — first re-runs the check, refuses with OpError::Conflict if not clean, then merges the source env into the target under the target’s transact lock and renames the source directory to a .dev-migrated-<ts> sentinel that’s hidden from EnvironmentStore::list (the leading dot is rejected by EnvId).

Scope is intentionally narrow:

• Refuses migration of any source env that carries bundles, revisions, traffic splits, or a credentials_ref — those require deep ref rewrites (env-scoped SecretRefs, BundleDeployment.env_id, etc.) which A4b’s “presence guarantee” semantic does not promise.
• On a “simple” source (only host_config + optional pack bindings), the merge preserves user-customized bindings on the target: defaults missing from target get filled from source; slots already bound on target stay untouched (the A4 #206 lesson — bootstrap is presence, not replacement).
• Audit-log scanning (A7) and secrets-store scanning (A4b PR4) ship as NotYetImplemented placeholders so the report surface is forward-stable.

Structs

AuditLogScanner

Placeholder for the audit-log scanner. A7 adds an append-only audit log keyed by env; until then we report a single informational finding so operators don’t expect this surface to silently catch missed references.

BundleHintScanner

Permanent no-op scanner — bundles carry no embedded env hint in any shipped code (per the A4b inventory), so any future drift would surface as a new scanner rather than a finding here.

LocalFsStoreScanner

Inspects the configured LocalFsStore root for a <from_env> directory. Classifies any source env as either a “simple” candidate (only host_config + optional pack bindings) or “complex” (carries bundles, revisions, traffic splits, or a credentials_ref).

MigrateDevApplyOutcome

Outcome of migrate-dev --apply. Only emitted when the check was clean.

MigrateDevReport

Report returned by migrate-dev --check.

MigrationFinding

One observation from a scanner run.

RuntimeConfigScanner

Reports a finding when GREENTIC_ENV is set to the legacy value in the process environment running the check. The migration tool can’t fix this from inside the process (the var is set in the caller’s shell), but flagging it informs the operator that their shell will still resolve dev after the on-disk migration.

ScanContext

Read-only context handed to every scanner.

SecretsStoreScanner

Placeholder for the secrets-store scanner. PR4 of A4b adds the real helper in greentic-secrets-broker; until then, no production code-paths enumerate dev-scoped keys, so this scanner reports a no-op informational finding.

Enums

FindingSeverity

Severity classification for a single finding.

Constants

LEGACY_ENV_ID

Legacy env-id this migration moves from. The target env-id is provided by the caller; defaults to LOCAL_ENV_ID in the binary clap layer.

Traits

MigrationScanner

Pluggable scanner — each implementation reports zero or more MigrationFindings for one slice of legacy dev-named state.

Functions

apply

op env migrate-dev <target> --apply. Re-runs the check, refuses with OpError::Conflict if not clean, then merges the source env into the target under the target’s transact lock and renames the source directory to a hidden .dev-migrated-<ts> sentinel.

check

op env migrate-dev <target> --check. Reports findings without touching state.

classify_runtime_env_var

Pure classification helper for RuntimeConfigScanner. Returns Some(finding) iff value equals the legacy env id. Extracted from the scanner so tests can exercise the logic without mutating the process environment — the crate is #![forbid(unsafe_code)] and Rust 2024 requires unsafe to set/remove env vars.

default_scanners

Bundle the set of scanners that ship with A4b. Future PRs add to this vector; consumers that want a different set can call the individual scanners directly.

run_check

Run every scanner and produce the report.