release: 1.6.0

Add 30-day send statistics and auto level-2 rate limits on the domain page. Close Unreleased; pin compose and docs to 1.6.0.

Co-authored-by: Cursor <cursoragent@cursor.com>

internal/store/applications.go

@@ -163,6 +163,25 @@ func (s *Store) GetApplication(id int64) (Application, error) {
 	return a, nil
 }
 
+// GetApplicationByLogin returns one application by its globally unique SASL login.
+func (s *Store) GetApplicationByLogin(login string) (Application, error) {
+	row := s.db.QueryRow(
+		"SELECT id, domain_id, login, address_mode, created_at FROM applications WHERE login = ?", login)
+	a, err := scanApplication(row)
+	if errors.Is(err, sql.ErrNoRows) {
+		return Application{}, ErrApplicationNotFound
+	}
+	if err != nil {
+		return Application{}, err
+	}
+	addrs, err := s.applicationAddresses(a.ID)
+	if err != nil {
+		return Application{}, err
+	}
+	a.Addresses = addrs
+	return a, nil
+}
+
 // ListApplicationsByDomain returns a domain's applications ordered by login,
 // each with its address list populated (product.md).
 func (s *Store) ListApplicationsByDomain(domainID int64) ([]Application, error) {

internal/store/migrations/0007_rate_limit_auto.sql

@@ -0,0 +1,7 @@
+-- Level-2 rate limit auto mode: operator sets a multiplier; max_messages is
+-- derived from 30-day send stats (plan domain-stats-auto-ratelimit).
+
+ALTER TABLE rate_limits ADD COLUMN mode TEXT NOT NULL DEFAULT 'manual'
+  CHECK (mode IN ('manual', 'auto'));
+ALTER TABLE rate_limits ADD COLUMN auto_multiplier REAL;
+ALTER TABLE rate_limits ADD COLUMN auto_updated_at TEXT;

internal/store/ratelimit_auto.go

@@ -0,0 +1,166 @@
+package store
+
+import (
+	"database/sql"
+	"fmt"
+	"log"
+	"math"
+	"time"
+)
+
+// RecalcAllAutoRateLimits recomputes max_messages for every auto-mode limit.
+// Store errors for individual rows are logged and skipped (fail-open on the
+// last successfully written limit). Returns how many rows were updated.
+func (s *Store) RecalcAllAutoRateLimits(retentionDays, l1Max, l1Window int) (int, error) {
+	rows, err := s.listAutoRateLimits()
+	if err != nil {
+		return 0, err
+	}
+	var updated int
+	for _, rl := range rows {
+		if err := s.recalcAutoRateLimit(rl, retentionDays, l1Max, l1Window); err != nil {
+			log.Printf("store: auto rate-limit recalc %s ref %d: %v", rl.Scope, rl.RefID, err)
+			continue
+		}
+		updated++
+	}
+	return updated, nil
+}
+
+// RecalcAutoRateLimit recomputes one auto-mode limit. Returns an error when
+// the row is missing or not in auto mode.
+func (s *Store) RecalcAutoRateLimit(scope string, refID int64, retentionDays, l1Max, l1Window int) error {
+	rl, ok, err := s.GetRateLimit(scope, refID)
+	if err != nil {
+		return err
+	}
+	if !ok || !rl.IsAuto() {
+		return fmt.Errorf("rate limit not in auto mode")
+	}
+	rl.Scope, rl.RefID = scope, refID
+	return s.recalcAutoRateLimit(rl, retentionDays, l1Max, l1Window)
+}
+
+func (s *Store) listAutoRateLimits() ([]RateLimit, error) {
+	rows, err := s.db.Query(
+		`SELECT scope, ref_id, allowed_ips, max_messages, window_seconds, mode, auto_multiplier, auto_updated_at
+		 FROM rate_limits WHERE mode = ?`, RateLimitModeAuto,
+	)
+	if err != nil {
+		return nil, fmt.Errorf("list auto rate limits: %w", err)
+	}
+	defer rows.Close()
+
+	var out []RateLimit
+	for rows.Next() {
+		var scope string
+		var refID int64
+		var ips sql.NullString
+		var maxMsgs, windowSecs sql.NullInt64
+		var mode sql.NullString
+		var autoMult sql.NullFloat64
+		var autoUpdated sql.NullString
+		if err := rows.Scan(&scope, &refID, &ips, &maxMsgs, &windowSecs, &mode, &autoMult, &autoUpdated); err != nil {
+			return nil, fmt.Errorf("scan auto rate limit: %w", err)
+		}
+		rl := RateLimit{
+			Scope:         scope,
+			RefID:         refID,
+			AllowedIPs:    splitIPs(ips.String),
+			MaxMessages:   int(maxMsgs.Int64),
+			WindowSeconds: int(windowSecs.Int64),
+			Mode:          mode.String,
+		}
+		if autoMult.Valid {
+			rl.AutoMultiplier = autoMult.Float64
+		}
+		if autoUpdated.Valid {
+			rl.AutoUpdatedAt, _ = time.Parse(time.RFC3339, autoUpdated.String)
+		}
+		out = append(out, rl)
+	}
+	return out, rows.Err()
+}
+
+func (s *Store) recalcAutoRateLimit(rl RateLimit, retentionDays, l1Max, l1Window int) error {
+	if !rl.IsAuto() {
+		return fmt.Errorf("not auto mode")
+	}
+	mult := rl.AutoMultiplier
+	if mult <= 0 {
+		mult = DefaultAutoMultiplier
+	}
+
+	var stats SendStats
+	var domainMax int
+	var domainActive bool
+
+	switch rl.Scope {
+	case RateLimitScopeDomain:
+		d, err := s.GetDomain(rl.RefID)
+		if err != nil {
+			return err
+		}
+		stats, err = s.DomainSendStats(d.Name, retentionDays, d.CreatedAt)
+		if err != nil {
+			return err
+		}
+	case RateLimitScopeApp:
+		a, err := s.GetApplication(rl.RefID)
+		if err != nil {
+			return err
+		}
+		stats, err = s.AppSendStats(a.Login, retentionDays, a.CreatedAt)
+		if err != nil {
+			return err
+		}
+		domainRL, ok, err := s.GetRateLimit(RateLimitScopeDomain, a.DomainID)
+		if err != nil {
+			return err
+		}
+		domainActive = ok && domainRL.Active()
+		if domainActive {
+			domainMax = domainRL.MaxMessages
+		}
+	default:
+		return fmt.Errorf("unknown scope %q", rl.Scope)
+	}
+
+	maxMsgs := computeAutoMaxMessages(stats, mult, l1Max)
+	if rl.Scope == RateLimitScopeApp {
+		maxMsgs = adjustAppAutoMax(maxMsgs, domainMax, domainActive, l1Max)
+	}
+
+	rl.MaxMessages = maxMsgs
+	rl.WindowSeconds = l1Window
+	rl.AutoUpdatedAt = time.Now().UTC()
+	if rl.AutoMultiplier <= 0 {
+		rl.AutoMultiplier = mult
+	}
+
+	return s.SetRateLimit(rl)
+}
+
+func computeAutoMaxMessages(stats SendStats, multiplier float64, l1Max int) int {
+	if stats.Total == 0 {
+		return 0
+	}
+	max := int(math.Ceil(stats.AvgPerHour * multiplier))
+	if max > l1Max {
+		max = l1Max
+	}
+	return max
+}
+
+func adjustAppAutoMax(appMax, domainMax int, domainActive bool, l1Max int) int {
+	if appMax <= 0 {
+		return 0
+	}
+	if domainActive && appMax <= domainMax {
+		appMax = domainMax + 1
+		if appMax > l1Max {
+			return 0
+		}
+	}
+	return appMax
+}

internal/store/ratelimits.go

@@ -17,6 +17,19 @@ const (
 	RateLimitScopeApp    = "application"
 )
 
+// Level-2 rate limit operating modes (plan domain-stats-auto-ratelimit).
+const (
+	RateLimitModeManual = "manual"
+	RateLimitModeAuto   = "auto"
+)
+
+// Auto rate-limit multiplier bounds shown in the panel.
+const (
+	DefaultAutoMultiplier = 2.5
+	MinAutoMultiplier     = 1.5
+	MaxAutoMultiplier     = 5.0
+)
+
 // RateLimit is a differentiated level-2 rate limit (guide § Rate limiting):
 // a message ceiling over a sliding window, attached to a domain or an
 // application. It is enforced in the journal-milter; level 1 (Postfix anvil,
@@ -28,16 +41,24 @@ const (
 // ceiling (above the domain) and skip the domain check; other IPs stay under
 // the domain limit or level 1 alone (guide § Rate limiting).
 type RateLimit struct {
-	Scope         string
-	RefID         int64
-	AllowedIPs    []string // trusted client IPs for an application override
-	MaxMessages   int
-	WindowSeconds int
+	Scope          string
+	RefID          int64
+	AllowedIPs     []string // trusted client IPs for an application override
+	MaxMessages    int
+	WindowSeconds  int
+	Mode           string  // manual | auto
+	AutoMultiplier float64 // used when Mode == auto
+	AutoUpdatedAt  time.Time
 }
 
 // Active reports whether the limit is fully configured and should be enforced.
 // Domain: max and window only. Application: also needs at least one trusted IP
 // (the privilege that raises the ceiling above the domain).
+// IsAuto reports whether the limit derives max_messages from send statistics.
+func (r RateLimit) IsAuto() bool {
+	return r.Mode == RateLimitModeAuto
+}
+
 func (r RateLimit) Active() bool {
 	if r.MaxMessages <= 0 || r.WindowSeconds <= 0 {
 		return false
@@ -69,7 +90,7 @@ func (r RateLimit) AllowsIP(ip string) bool {
 // its id, for the panel's edit form. ok is false when none is configured.
 func (s *Store) GetRateLimit(scope string, refID int64) (RateLimit, bool, error) {
 	row := s.db.QueryRow(
-		`SELECT allowed_ips, max_messages, window_seconds
+		`SELECT allowed_ips, max_messages, window_seconds, mode, auto_multiplier, auto_updated_at
 		 FROM rate_limits WHERE scope = ? AND ref_id = ?`, scope, refID)
 	rl, err := scanRateLimit(row)
 	if errors.Is(err, sql.ErrNoRows) {
@@ -86,14 +107,30 @@ func (s *Store) GetRateLimit(scope string, refID int64) (RateLimit, bool, error)
 // (panel) has already validated the IPs and numbers (security.md); values are
 // stored via bound parameters and read back live by the milter.
 func (s *Store) SetRateLimit(rl RateLimit) error {
+	mode := rl.Mode
+	if mode == "" {
+		mode = RateLimitModeManual
+	}
+	var autoMult interface{}
+	if rl.IsAuto() {
+		autoMult = rl.AutoMultiplier
+	}
+	var autoUpdated interface{}
+	if !rl.AutoUpdatedAt.IsZero() {
+		autoUpdated = rl.AutoUpdatedAt.UTC().Format(time.RFC3339)
+	}
 	_, err := s.db.Exec(
-		`INSERT INTO rate_limits (scope, ref_id, allowed_ips, max_messages, window_seconds)
-		 VALUES (?, ?, ?, ?, ?)
+		`INSERT INTO rate_limits (scope, ref_id, allowed_ips, max_messages, window_seconds, mode, auto_multiplier, auto_updated_at)
+		 VALUES (?, ?, ?, ?, ?, ?, ?, ?)
 		 ON CONFLICT(scope, ref_id) DO UPDATE SET
-		   allowed_ips    = excluded.allowed_ips,
-		   max_messages   = excluded.max_messages,
-		   window_seconds = excluded.window_seconds`,
+		   allowed_ips       = excluded.allowed_ips,
+		   max_messages      = excluded.max_messages,
+		   window_seconds    = excluded.window_seconds,
+		   mode              = excluded.mode,
+		   auto_multiplier   = excluded.auto_multiplier,
+		   auto_updated_at   = excluded.auto_updated_at`,
 		rl.Scope, rl.RefID, strings.Join(rl.AllowedIPs, ","), rl.MaxMessages, rl.WindowSeconds,
+		mode, autoMult, autoUpdated,
 	)
 	if err != nil {
 		return fmt.Errorf("set rate limit: %w", err)
@@ -134,11 +171,11 @@ func (s *Store) RateLimit(scope, ref string) (RateLimit, bool, error) {
 	var query string
 	switch scope {
 	case RateLimitScopeDomain:
-		query = `SELECT rl.allowed_ips, rl.max_messages, rl.window_seconds
+		query = `SELECT rl.allowed_ips, rl.max_messages, rl.window_seconds, rl.mode, rl.auto_multiplier, rl.auto_updated_at
 		         FROM rate_limits rl JOIN domains d ON d.id = rl.ref_id
 		         WHERE rl.scope = 'domain' AND d.name = ?`
 	case RateLimitScopeApp:
-		query = `SELECT rl.allowed_ips, rl.max_messages, rl.window_seconds
+		query = `SELECT rl.allowed_ips, rl.max_messages, rl.window_seconds, rl.mode, rl.auto_multiplier, rl.auto_updated_at
 		         FROM rate_limits rl JOIN applications a ON a.id = rl.ref_id
 		         WHERE rl.scope = 'application' AND a.login = ?`
 	default:
@@ -191,18 +228,29 @@ func (s *Store) CountMessages(scope, ref string, since time.Time) (int64, error)
 // Active() until max and window are both set.
 func scanRateLimit(r scanRow) (RateLimit, error) {
 	var (
-		ips        sql.NullString
-		maxMsgs    sql.NullInt64
-		windowSecs sql.NullInt64
+		ips         sql.NullString
+		maxMsgs     sql.NullInt64
+		windowSecs  sql.NullInt64
+		mode        sql.NullString
+		autoMult    sql.NullFloat64
+		autoUpdated sql.NullString
 	)
-	if err := r.Scan(&ips, &maxMsgs, &windowSecs); err != nil {
+	if err := r.Scan(&ips, &maxMsgs, &windowSecs, &mode, &autoMult, &autoUpdated); err != nil {
 		return RateLimit{}, err
 	}
-	return RateLimit{
+	rl := RateLimit{
 		AllowedIPs:    splitIPs(ips.String),
 		MaxMessages:   int(maxMsgs.Int64),
 		WindowSeconds: int(windowSecs.Int64),
-	}, nil
+		Mode:          mode.String,
+	}
+	if autoMult.Valid {
+		rl.AutoMultiplier = autoMult.Float64
+	}
+	if autoUpdated.Valid {
+		rl.AutoUpdatedAt, _ = time.Parse(time.RFC3339, autoUpdated.String)
+	}
+	return rl, nil
 }
 
 // splitIPs parses the comma-separated storage form back into a slice, dropping

internal/store/ratelimits_test.go

@@ -1,6 +1,7 @@
 package store
 
 import (
+	"fmt"
 	"testing"
 	"time"
 )
@@ -184,3 +185,92 @@ func TestRateLimitActiveAndAllowsIP(t *testing.T) {
 		t.Fatalf("unregistered/invalid IPs must not match")
 	}
 }
+
+func TestAutoRateLimitRecalc(t *testing.T) {
+	st := openTestStore(t)
+	d, _ := st.AddDomain("example.com", "selfpost")
+	a, _ := st.AddApplication(d.ID, "app1", AddressModeWildcard, nil)
+
+	for i := 0; i < 10; i++ {
+		if err := st.InsertQueued(SendLogEntry{
+			QueueID: fmt.Sprintf("Q%d", i), Domain: "example.com", AppLogin: "app1", To: "t@x.net",
+		}); err != nil {
+			t.Fatalf("InsertQueued: %v", err)
+		}
+	}
+
+	if err := st.SetRateLimit(RateLimit{
+		Scope: RateLimitScopeDomain, RefID: d.ID, Mode: RateLimitModeAuto,
+		AutoMultiplier: 2.0, WindowSeconds: 3600,
+	}); err != nil {
+		t.Fatalf("SetRateLimit domain: %v", err)
+	}
+	if err := st.RecalcAutoRateLimit(RateLimitScopeDomain, d.ID, 90, 100, 3600); err != nil {
+		t.Fatalf("RecalcAutoRateLimit domain: %v", err)
+	}
+	rl, ok, err := st.GetRateLimit(RateLimitScopeDomain, d.ID)
+	if err != nil || !ok {
+		t.Fatalf("GetRateLimit: ok=%v err=%v", ok, err)
+	}
+	if !rl.Active() || rl.MaxMessages > 100 {
+		t.Fatalf("domain auto limit = %+v", rl)
+	}
+	if rl.WindowSeconds != 3600 {
+		t.Fatalf("window = %d, want 3600", rl.WindowSeconds)
+	}
+
+	// Domain limit at ceiling; app auto must be strictly above or inactive at L1.
+	_ = st.SetRateLimit(RateLimit{
+		Scope: RateLimitScopeDomain, RefID: d.ID, Mode: RateLimitModeManual,
+		MaxMessages: 100, WindowSeconds: 3600,
+	})
+	if err := st.SetRateLimit(RateLimit{
+		Scope: RateLimitScopeApp, RefID: a.ID, Mode: RateLimitModeAuto,
+		AllowedIPs: []string{"203.0.113.1"}, AutoMultiplier: 2.0,
+	}); err != nil {
+		t.Fatalf("SetRateLimit app: %v", err)
+	}
+	if err := st.RecalcAutoRateLimit(RateLimitScopeApp, a.ID, 90, 100, 3600); err != nil {
+		t.Fatalf("RecalcAutoRateLimit app: %v", err)
+	}
+	appRL, ok, _ := st.GetRateLimit(RateLimitScopeApp, a.ID)
+	if ok && appRL.Active() {
+		t.Fatalf("app auto at L1 cap with domain at L1 should be inactive: %+v", appRL)
+	}
+
+	_ = st.SetRateLimit(RateLimit{
+		Scope: RateLimitScopeDomain, RefID: d.ID, Mode: RateLimitModeManual,
+		MaxMessages: 40, WindowSeconds: 3600,
+	})
+	if err := st.RecalcAutoRateLimit(RateLimitScopeApp, a.ID, 90, 100, 3600); err != nil {
+		t.Fatalf("RecalcAutoRateLimit app: %v", err)
+	}
+	appRL, ok, _ = st.GetRateLimit(RateLimitScopeApp, a.ID)
+	if !ok || !appRL.Active() || appRL.MaxMessages <= 40 {
+		t.Fatalf("app auto should be above domain 40: %+v", appRL)
+	}
+
+	// Milter reads the stored ceiling via RateLimit(name/login).
+	milterRL, ok, err := st.RateLimit(RateLimitScopeDomain, "example.com")
+	if err != nil || !ok || milterRL.MaxMessages != 40 {
+		t.Fatalf("milter domain limit = %+v ok=%v err=%v", milterRL, ok, err)
+	}
+}
+
+func TestAutoRateLimitZeroTrafficInactive(t *testing.T) {
+	st := openTestStore(t)
+	d, _ := st.AddDomain("quiet.com", "selfpost")
+	if err := st.SetRateLimit(RateLimit{
+		Scope: RateLimitScopeDomain, RefID: d.ID, Mode: RateLimitModeAuto,
+		AutoMultiplier: 2.5,
+	}); err != nil {
+		t.Fatalf("SetRateLimit: %v", err)
+	}
+	if err := st.RecalcAutoRateLimit(RateLimitScopeDomain, d.ID, 90, 100, 3600); err != nil {
+		t.Fatalf("RecalcAutoRateLimit: %v", err)
+	}
+	rl, ok, _ := st.GetRateLimit(RateLimitScopeDomain, d.ID)
+	if ok && rl.Active() {
+		t.Fatalf("zero traffic auto should be inactive: %+v", rl)
+	}
+}

internal/store/stats.go

@@ -0,0 +1,101 @@
+package store
+
+import (
+	"fmt"
+	"math"
+	"time"
+)
+
+// StatsWindowDays is the rolling window for send statistics on the domain page.
+const StatsWindowDays = 30
+
+// SendStats holds message-volume metrics over a stats window (guide § Rate
+// limiting — same counting rules as CountMessages).
+type SendStats struct {
+	Total       int64
+	PeakPerHour int64
+	AvgPerHour  float64
+	WindowDays  int   // actual days queried (min(30, retention))
+	WindowHours float64 // hours used for the average-rate denominator
+}
+
+// StatsWindow computes the since timestamp and hours denominator for send
+// statistics. The query window is min(30, retention) days; hours_in_window is
+// min(720, entity age in hours, retention hours).
+func StatsWindow(retentionDays int, entityCreated time.Time) (since time.Time, hours float64, windowDays int) {
+	if retentionDays <= 0 {
+		retentionDays = SendLogRetentionDaysDefault
+	}
+	windowDays = StatsWindowDays
+	if retentionDays < StatsWindowDays {
+		windowDays = retentionDays
+	}
+	since = time.Now().UTC().AddDate(0, 0, -windowDays)
+
+	retentionHours := float64(retentionDays) * 24
+	ageHours := time.Since(entityCreated).Hours()
+	if ageHours < 0 {
+		ageHours = 0
+	}
+
+	hours = math.Min(720, math.Min(ageHours, retentionHours))
+	if hours < 1 {
+		hours = 1
+	}
+	return since, hours, windowDays
+}
+
+// DomainSendStats returns 30-day (or shorter when retention is lower) send
+// statistics for a domain name.
+func (s *Store) DomainSendStats(name string, retentionDays int, createdAt time.Time) (SendStats, error) {
+	since, hours, windowDays := StatsWindow(retentionDays, createdAt)
+	stats, err := s.sendStats("domain", name, since, hours)
+	if err != nil {
+		return SendStats{}, err
+	}
+	stats.WindowDays = windowDays
+	stats.WindowHours = hours
+	return stats, nil
+}
+
+// AppSendStats returns send statistics for an application login.
+func (s *Store) AppSendStats(login string, retentionDays int, createdAt time.Time) (SendStats, error) {
+	since, hours, windowDays := StatsWindow(retentionDays, createdAt)
+	stats, err := s.sendStats("app_login", login, since, hours)
+	if err != nil {
+		return SendStats{}, err
+	}
+	stats.WindowDays = windowDays
+	stats.WindowHours = hours
+	return stats, nil
+}
+
+func (s *Store) sendStats(column, ref string, since time.Time, hours float64) (SendStats, error) {
+	sinceStr := since.UTC().Format(time.RFC3339)
+
+	var total int64
+	err := s.db.QueryRow(
+		`SELECT COUNT(DISTINCT queue_id) FROM send_log
+		 WHERE `+column+` = ? AND status != ? AND created_at >= ?`,
+		ref, StatusRejected, sinceStr,
+	).Scan(&total)
+	if err != nil {
+		return SendStats{}, fmt.Errorf("send stats total %s %q: %w", column, ref, err)
+	}
+
+	var peak int64
+	err = s.db.QueryRow(
+		`SELECT COALESCE(MAX(bucket_count), 0) FROM (
+		   SELECT COUNT(DISTINCT queue_id) AS bucket_count FROM send_log
+		   WHERE `+column+` = ? AND status != ? AND created_at >= ?
+		   GROUP BY substr(created_at, 1, 13)
+		 )`,
+		ref, StatusRejected, sinceStr,
+	).Scan(&peak)
+	if err != nil {
+		return SendStats{}, fmt.Errorf("send stats peak %s %q: %w", column, ref, err)
+	}
+
+	avg := float64(total) / hours
+	return SendStats{Total: total, PeakPerHour: peak, AvgPerHour: avg}, nil
+}

internal/store/stats_test.go

@@ -0,0 +1,78 @@
+package store
+
+import (
+	"testing"
+	"time"
+)
+
+func TestSendStatsTotalPeakAvg(t *testing.T) {
+	st := openTestStore(t)
+	d, err := st.AddDomain("example.com", "selfpost")
+	if err != nil {
+		t.Fatalf("AddDomain: %v", err)
+	}
+	a, err := st.AddApplication(d.ID, "app1", AddressModeWildcard, nil)
+	if err != nil {
+		t.Fatalf("AddApplication: %v", err)
+	}
+
+	now := time.Now().UTC()
+	hour := now.Format("2006-01-02T15")
+	prevHour := now.Add(-2 * time.Hour).Format("2006-01-02T15")
+
+	// Hour 1: two messages (Q1 two recipients + Q2).
+	for _, to := range []string{"a@x.net", "b@x.net"} {
+		if err := st.InsertQueued(SendLogEntry{QueueID: "Q1", Domain: "example.com", AppLogin: "app1", To: to}); err != nil {
+			t.Fatalf("InsertQueued: %v", err)
+		}
+	}
+	if err := st.InsertQueued(SendLogEntry{QueueID: "Q2", Domain: "example.com", AppLogin: "app1", To: "c@x.net"}); err != nil {
+		t.Fatalf("InsertQueued: %v", err)
+	}
+	// Hour 2: one message.
+	if _, err := st.db.Exec(`UPDATE send_log SET created_at = ? WHERE queue_id = 'Q2'`,
+		prevHour+":00:00Z"); err != nil {
+		t.Fatalf("backdate Q2: %v", err)
+	}
+	if _, err := st.db.Exec(`UPDATE send_log SET created_at = ? WHERE queue_id = 'Q1'`,
+		hour+":10:00Z"); err != nil {
+		t.Fatalf("backdate Q1: %v", err)
+	}
+	if err := st.InsertRejected(SendLogEntry{Domain: "example.com", AppLogin: "app1"}); err != nil {
+		t.Fatalf("InsertRejected: %v", err)
+	}
+
+	stats, err := st.DomainSendStats("example.com", 90, d.CreatedAt)
+	if err != nil {
+		t.Fatalf("DomainSendStats: %v", err)
+	}
+	if stats.Total != 2 {
+		t.Fatalf("total = %d, want 2", stats.Total)
+	}
+	if stats.PeakPerHour != 1 {
+		t.Fatalf("peak = %d, want 1 (one message per hour bucket)", stats.PeakPerHour)
+	}
+	if stats.AvgPerHour <= 0 {
+		t.Fatalf("avg should be positive, got %v", stats.AvgPerHour)
+	}
+
+	appStats, err := st.AppSendStats("app1", 90, a.CreatedAt)
+	if err != nil {
+		t.Fatalf("AppSendStats: %v", err)
+	}
+	if appStats.Total != 2 {
+		t.Fatalf("app total = %d, want 2", appStats.Total)
+	}
+}
+
+func TestStatsWindowShortRetention(t *testing.T) {
+	st := openTestStore(t)
+	d, _ := st.AddDomain("example.com", "selfpost")
+	stats, err := st.DomainSendStats("example.com", 7, d.CreatedAt)
+	if err != nil {
+		t.Fatalf("DomainSendStats: %v", err)
+	}
+	if stats.WindowDays != 7 {
+		t.Fatalf("window days = %d, want 7", stats.WindowDays)
+	}
+}