metrics

type Metrics struct {

	// ── Write path ──────────────────────────────────────────────────────────
	// PayloadProcessingLatency is the end-to-end write path latency, labeled
	// by source. Observed in handleWrite on each accepted payload.
	PayloadProcessingLatency *prometheus.HistogramVec

	// ThroughputPerSource counts successful writes per source.
	// Incremented in handleWrite after WAL + enqueue succeed.
	ThroughputPerSource *prometheus.CounterVec

	// ErrorsTotal counts errors by type label (e.g. "wal_append", "unmarshal").
	// Incremented whenever a write or queue operation fails fatally.
	ErrorsTotal *prometheus.CounterVec

	// ── Read path ────────────────────────────────────────────────────────────
	// ReadLatency is the end-to-end read path latency, labeled by source and
	// endpoint. Observed in handleQuery on each completed read.
	ReadLatency *prometheus.HistogramVec

	// ── Queue ────────────────────────────────────────────────────────────────
	// QueueDepth is the current number of entries buffered in the queue channel.
	// Updated by the daemon's watchdog goroutine and on each enqueue/dequeue.
	QueueDepth prometheus.Gauge

	// QueueProcessingRate counts payloads successfully dequeued and written.
	// Incremented by the queue worker on each successful destination write.
	QueueProcessingRate prometheus.Counter

	// ── WAL ──────────────────────────────────────────────────────────────────
	// WALPendingEntries is the count of WAL entries not yet DELIVERED.
	// Set after replay and updated by the WAL watchdog.
	WALPendingEntries prometheus.Gauge

	// WALDiskBytesFree is the available disk space on the WAL partition.
	// Updated by the WAL watchdog and doctor.
	WALDiskBytesFree prometheus.Gauge

	// WALHealthy is 1 when the WAL watchdog reports healthy, 0 otherwise.
	// Set by the WAL watchdog goroutine.
	WALHealthy prometheus.Gauge

	// WALAppendLatency is the per-Append fsync latency.
	// Observed in handleWrite around each wal.Append call.
	WALAppendLatency prometheus.Histogram

	// WALCRCFailures counts CRC32 mismatches detected during replay.
	// Incremented after replay by syncing WAL.CRCFailures().
	WALCRCFailures prometheus.Counter

	// WALIntegrityFailures counts HMAC mismatches during replay (integrity=mac).
	// Incremented when integrity checking is enabled and a MAC fails.
	WALIntegrityFailures prometheus.Counter

	// ── Replay ───────────────────────────────────────────────────────────────
	// ReplayEntriesTotal counts WAL entries processed during startup replay.
	// Incremented once per PENDING entry in replayWAL.
	ReplayEntriesTotal prometheus.Counter

	// ReplayDurationSeconds records the wall-clock time spent on WAL replay.
	// Set (not incremented) in replayWAL after replay completes.
	ReplayDurationSeconds prometheus.Gauge

	// ── Auth ─────────────────────────────────────────────────────────────────
	// AuthFailuresTotal counts authentication failures by source label.
	// Incremented in authenticate() when no key matches.
	AuthFailuresTotal *prometheus.CounterVec

	// ── Policy ───────────────────────────────────────────────────────────────
	// PolicyDenialsTotal counts policy gate rejections by source and reason.
	// Incremented whenever a policy check denies a request (403).
	// Reference: Tech Spec Section 11.3.
	PolicyDenialsTotal *prometheus.CounterVec

	// ── Rate limit ───────────────────────────────────────────────────────────
	// RateLimitHitsTotal counts rate limit rejections by source label.
	// Incremented in handleWrite and handleQuery when Allow() returns false.
	RateLimitHitsTotal *prometheus.CounterVec

	// ── Admin ────────────────────────────────────────────────────────────────
	// AdminCallsTotal counts admin endpoint calls by endpoint label.
	// Incremented in the admin middleware (requireAdminToken success path).
	AdminCallsTotal *prometheus.CounterVec

	// ── Config ───────────────────────────────────────────────────────────────
	// ConfigLintWarnings is the number of non-fatal config lint warnings.
	// Set after config load and after each hot reload.
	ConfigLintWarnings prometheus.Gauge

	// ── Embedding (Stage 4) ──────────────────────────────────────────────────
	// EmbeddingLatency is the end-to-end embedding provider call duration.
	// Observed in the cascade Stage 4 path on each Embed() call.
	// Reference: Tech Spec Section 11.3.
	EmbeddingLatency prometheus.Histogram

	// ── Temporal Decay (Stage 5) ─────────────────────────────────────────────
	// TemporalDecayApplied counts the number of times temporal decay reranking
	// was applied in Stage 5 (Hybrid Merge + Temporal Decay).
	// Reference: Tech Spec Section 11.3.
	TemporalDecayApplied prometheus.Counter

	// ── Visualization ───────────────────────────────────────────────────────
	// VizEventsDroppedTotal counts pipeline visualization events dropped
	// (channel full). Reference: Tech Spec Section 11.3.
	VizEventsDroppedTotal prometheus.Counter

	// ── Event Sink ──────────────────────────────────────────────────────────
	// EventsDroppedTotal counts event sink events dropped (channel full).
	// Reference: Tech Spec Section 11.3.
	EventsDroppedTotal prometheus.Counter

	// EventsDeliveredTotal counts event sink events successfully delivered.
	// Reference: Tech Spec Section 11.3.
	EventsDeliveredTotal prometheus.Counter

	// EventsFailedTotal counts event sink delivery failures (retries exhausted).
	// Reference: Tech Spec Section 11.3.
	EventsFailedTotal prometheus.Counter

	// ── Consistency ──────────────────────────────────────────────────────────
	// ConsistencyScore is the WAL-to-destination consistency score (0.0–1.0).
	// Set by the consistency checker background goroutine.
	// Reference: Tech Spec Section 11.5.
	ConsistencyScore prometheus.Gauge

	// ── Audit (Interaction Log) ─────────────────────────────────────────────
	// AuditLogErrorsTotal counts audit log write failures by file label
	// (primary or shadow). Incremented when a write or fsync fails.
	// Reference: Update U1.3.
	AuditLogErrorsTotal *prometheus.CounterVec

	// AuditShadowErrorsTotal counts shadow file write failures.
	// Reference: Update U1.7.
	AuditShadowErrorsTotal prometheus.Counter

	// AuditCRCFailuresTotal counts records where both primary and shadow had
	// CRC32 mismatches (unrecoverable corruption).
	// Reference: Update U1.7.
	AuditCRCFailuresTotal prometheus.Counter

	// AuditShadowRecoveriesTotal counts records recovered from shadow after
	// primary corruption.
	// Reference: Update U1.7.
	AuditShadowRecoveriesTotal prometheus.Counter

	// ── Audit (Interaction Log) — API & Emission ───────────────────────────
	// AuditRecordsTotal counts interaction records written, labeled by
	// operation_type and policy_decision.
	// Reference: Tech Spec Addendum Section A2.6.
	AuditRecordsTotal *prometheus.CounterVec

	// AuditLogBytes is the current interaction log file size in bytes.
	// Reference: Tech Spec Addendum Section A2.6.
	AuditLogBytes prometheus.Gauge

	// AuditLogRotationTotal counts interaction log file rotations.
	// Reference: Tech Spec Addendum Section A2.6.
	AuditLogRotationTotal prometheus.Counter

	// AuditQueryLatency is the /api/audit/log query latency.
	// Reference: Tech Spec Addendum Section A2.6.
	AuditQueryLatency prometheus.Histogram

	// ── Retrieval Firewall ──────────────────────────────────────────────────
	// FirewallFilteredTotal counts memories filtered (removed) by the retrieval
	// firewall, labeled by source and label that triggered the filter.
	// Reference: Tech Spec Addendum Section A2.6, A3.8.
	FirewallFilteredTotal *prometheus.CounterVec

	// FirewallDeniedTotal counts queries fully denied by the retrieval firewall,
	// labeled by source.
	// Reference: Tech Spec Addendum Section A2.6, A3.8.
	FirewallDeniedTotal *prometheus.CounterVec

	// FirewallLatency is the retrieval firewall filtering duration, labeled by
	// source. Reference: Tech Spec Addendum Section A3.8.
	FirewallLatency *prometheus.HistogramVec
	// contains filtered or unexported fields
}