Statistics page: the statistics database's size, and a fullness bar on the disk tiles

The server section shows the statistics database's size (with its -wal and -shm) and how many answers the query log holds, linking to the dashboard's Storage panel; the disk tiles get the same bar as the dashboard. GET /stats/server has database {path, bytes, query_log_rows}.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

internal/server/h_stats.go

@@ -283,6 +283,16 @@ func (s *Server) statsServer(w http.ResponseWriter, r *http.Request, p *auth.Pri
 		labels = append(labels, "statistics database")
 	}
 	out["disks"] = stats.DiskUsage(labels, dirs)
+	// The statistics database: what the statistics cost on disk.
+	if db := s.cfg.Stats.Store().Path(); db != "" && db != ":memory:" {
+		info := map[string]any{"path": db, "bytes": dbBytes(db)}
+		if keep := s.cfg.Stats.Options().RetainQueries; keep > 0 && s.cfg.Stats.Options().QueryLog {
+			if n, err := s.cfg.Stats.Store().QueryLogSize(r.Context()); err == nil {
+				info["query_log_rows"] = n
+			}
+		}
+		out["database"] = info
+	}
 	writeJSON(w, http.StatusOK, out)
 	return nil
 }

internal/server/h_storage.go

@@ -18,12 +18,7 @@ func (s *Server) storage(ctx context.Context) *api.Storage {
 		if path == "" || path == ":memory:" {
 			return nil
 		}
-		d := api.Database{Label: label, Path: path}
-		for _, suffix := range []string{"", "-wal", "-shm"} {
-			if fi, err := os.Stat(path + suffix); err == nil {
-				d.Bytes += fi.Size()
-			}
-		}
+		d := api.Database{Label: label, Path: path, Bytes: dbBytes(path)}
 		out.Databases = append(out.Databases, d)
 		out.Total += d.Bytes
 		return &out.Databases[len(out.Databases)-1]
@@ -70,3 +65,14 @@ func (s *Server) storage(ctx context.Context) *api.Storage {
 	}
 	return out
 }
+
+// dbBytes is the size of a SQLite database: its file, -wal and -shm.
+func dbBytes(path string) int64 {
+	var n int64
+	for _, suffix := range []string{"", "-wal", "-shm"} {
+		if fi, err := os.Stat(path + suffix); err == nil {
+			n += fi.Size()
+		}
+	}
+	return n
+}

internal/server/stats_test.go

@@ -5,6 +5,7 @@ import (
 	"encoding/json"
 	"io"
 	"log/slog"
+	"path/filepath"
 	"strings"
 	"testing"
 	"time"
@@ -176,3 +177,24 @@ func TestStatsExploreAPI(t *testing.T) {
 		t.Errorf("storage %v", st["storage"])
 	}
 }
+
+// /stats/server reports the statistics database's size and the query log.
+func TestStatsServerDatabase(t *testing.T) {
+	ss, err := stats.OpenStore(filepath.Join(t.TempDir(), "stats.db"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer ss.Close()
+	b := &stats.Batch{}
+	b.AddQueries([]stats.QueryRow{{Time: time.Now().Unix(), Client: "10.0.0.7", View: "internal", Name: "www.example.com", Type: "A", RCode: "NOERROR"}})
+	if err := ss.Commit(context.Background(), b); err != nil {
+		t.Fatal(err)
+	}
+	opts := stats.Options{QueryLog: true, StatisticsChannel: "127.0.0.1:1", TopN: 10, RetainMinute: time.Hour, RetainHour: 24 * time.Hour, RetainDay: 24 * time.Hour, RetainQueries: 7 * 24 * time.Hour}
+	e := newAPIEnv(t, stats.NewCollector(ss, opts, nil, slog.New(slog.NewTextHandler(io.Discard, nil))))
+	sv := e.do("GET", "/stats/server", e.token, nil, 200)
+	db, ok := sv["database"].(map[string]any)
+	if !ok || db["bytes"].(float64) <= 0 || db["query_log_rows"].(float64) != 1 {
+		t.Errorf("database %v", sv["database"])
+	}
+}