inputsnapshot

func Compute ¶

func Compute(varNames []string, lookup func(string) (string, bool)) map[string]string

Compute returns a map of env-var name → 16-hex-char sha256 prefix of the value. Variables that aren't set (lookup returns ok=false) are omitted from the snapshot.

func ComputeDrift ¶

func ComputeDrift(planSnap, applySnap map[string]string) []interfaces.DriftEntry

ComputeDrift compares plan-time vs apply-time fingerprint snapshots and produces a drift report. Iterates over planSnap keys (no phantom InputNames field needed; map keys ARE the names). Honors the in-package preservedFingerprint sentinel from snapshot.go — keys whose applySnap value equals the sentinel are skipped (sub-action cleanup case).

Cross-function contract:

• Compute (snapshot.go) passes the sentinel through unhashed.
• NewTolerantEnvProvider (snapshot.go, sole sanctioned injector) returns the sentinel for plan-time-set apply-time-unset vars.
• ComputeDrift (this function) honors the sentinel by skipping the entry.

func FormatStaleError ¶

func FormatStaleError(drift []interfaces.DriftEntry) string

FormatStaleError renders a drift report into the canonical human-readable message used at every plan-stale call site (cmd/wfctl/infra.go persisted `--plan` path; wfctlhelpers.ApplyPlan in-process path in T3.1.5). Output:

plan stale: %d input(s) changed since plan
  KEY1: fingerprint planFP1 (plan) → applyFP1 (apply)
  KEY2: fingerprint planFP2 (plan) → applyFP2 (apply)
  hint: ensure all env vars referenced by your infra config are exported to both Plan and Apply steps

Drift entries are sorted by Name for deterministic output. An empty drift report yields the singular header line "plan stale: 0 input(s) changed since plan" with no trailing hint — callers should avoid invoking the formatter when no drift exists, but if they do the output stays minimal.

func NewTolerantEnvProvider ¶

func NewTolerantEnvProvider(planSnapshot map[string]string) func(name string) (string, bool)

NewTolerantEnvProvider returns an EnvProvider closure used by the in-process apply postcondition (T3.1.5). When a var was set at plan time (present in planSnapshot) but is now unset (sub-action cleanup), the closure returns the in-package preservedFingerprint sentinel so ComputeDrift suppresses the (false-positive) drift entry. For vars genuinely unset at both times, returns ("", false) → Compute drops the key from the resulting map.

This is the ONLY sanctioned way to inject the preservation sentinel. The sentinel constant is unexported, so external code cannot reference it by name; a determined caller could still return the literal string from a custom env-provider, but doing so is a deliberate discipline violation rather than a tooling bypass.

func OSEnvProvider ¶

func OSEnvProvider(name string) (string, bool)

OSEnvProvider is the canonical env-provider closure that reads from process env via os.LookupEnv. Used by start-of-apply InputSnapshot capture.

func Snapshot ¶

func Snapshot(names []string, provider func(string) (string, bool)) map[string]string

Snapshot is an alias for Compute that reads slightly more naturally at the in-process apply postcondition call site (T3.1.5).