cmd/speedtest-sync: fail-fast on bad timestamps + minor cleanups

- Skip rows with null/malformed timestamps instead of silently
  re-stamping with time.Now() (data corruption hidden behind a
  fallback). Drops the time import.
- Replace ad-hoc parentDir() with stdlib filepath.Dir().
- Add t.Fatal error checks to TestExtractRows_SkipsBadExtra
  (CREATE TABLE / INSERT) and switch sql.Open to checked form.
- New TestExtractRows_SkipsBadTimestamp covers the null-ts path.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

cmd/speedtest-sync/main.go

@@ -6,6 +6,7 @@ import (
 	"flag"
 	"log"
 	"os"
+	"path/filepath"
 	"strconv"
 	"time"
 
@@ -99,17 +100,8 @@ func readCursor(path string) int64 {
 }
 
 func writeCursor(path string, id int64) error {
-	if err := os.MkdirAll(parentDir(path), 0o755); err != nil {
+	if err := os.MkdirAll(filepath.Dir(path), 0o755); err != nil {
 		return err
 	}
 	return os.WriteFile(path, []byte(strconv.FormatInt(id, 10)), 0o600)
 }
-
-func parentDir(p string) string {
-	for i := len(p) - 1; i >= 0; i-- {
-		if p[i] == '/' {
-			return p[:i]
-		}
-	}
-	return "."
-}

cmd/speedtest-sync/sync.go

@@ -6,7 +6,6 @@ import (
 	"encoding/json"
 	"fmt"
 	"log"
-	"time"
 
 	pb "github.com/bergabruh/stats-gateway/gen/stats/v1"
 )
@@ -63,12 +62,14 @@ func extractRows(ctx context.Context, db *sql.DB, sinceID int64) ([]extractedRow
 			continue
 		}
 
-		var tsUnix int64
-		if ts.Valid {
-			fmt.Sscanf(ts.String, "%d", &tsUnix)
+		if !ts.Valid {
+			log.Printf("skip id=%d: null timestamp", id)
+			continue
 		}
-		if tsUnix == 0 {
-			tsUnix = time.Now().Unix()
+		var tsUnix int64
+		if _, err := fmt.Sscanf(ts.String, "%d", &tsUnix); err != nil || tsUnix == 0 {
+			log.Printf("skip id=%d: bad timestamp %q", id, ts.String)
+			continue
 		}
 
 		out = append(out, extractedRow{

cmd/speedtest-sync/sync_test.go

@@ -54,15 +54,22 @@ func TestExtractRows_FiltersExtraJSON(t *testing.T) {
 func TestExtractRows_SkipsBadExtra(t *testing.T) {
 	dir := t.TempDir()
 	dbPath := filepath.Join(dir, "test.db")
-	db, _ := sql.Open("sqlite", dbPath)
+	db, err := sql.Open("sqlite", dbPath)
+	if err != nil {
+		t.Fatal(err)
+	}
 	defer db.Close()
 
-	db.Exec(`CREATE TABLE speedtest_users (
+	if _, err := db.Exec(`CREATE TABLE speedtest_users (
 		id INTEGER PRIMARY KEY AUTOINCREMENT,
 		timestamp DATETIME, ip TEXT, ispinfo TEXT, extra TEXT,
-		ua TEXT, lang TEXT, dl REAL, ul REAL, ping REAL, jitter REAL, log TEXT)`)
-	db.Exec(`INSERT INTO speedtest_users(timestamp, extra, dl, ul, ping, jitter)
-             VALUES(datetime('now'), 'not-json', 1, 1, 1, 1)`)
+		ua TEXT, lang TEXT, dl REAL, ul REAL, ping REAL, jitter REAL, log TEXT)`); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := db.Exec(`INSERT INTO speedtest_users(timestamp, extra, dl, ul, ping, jitter)
+             VALUES(datetime('now'), 'not-json', 1, 1, 1, 1)`); err != nil {
+		t.Fatal(err)
+	}
 
 	rows, err := extractRows(context.Background(), db, 0)
 	if err != nil {
@@ -72,3 +79,35 @@ func TestExtractRows_SkipsBadExtra(t *testing.T) {
 		t.Errorf("expected 0 rows (bad extra skipped), got %d", len(rows))
 	}
 }
+
+func TestExtractRows_SkipsBadTimestamp(t *testing.T) {
+	dir := t.TempDir()
+	dbPath := filepath.Join(dir, "test.db")
+	db, err := sql.Open("sqlite", dbPath)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer db.Close()
+
+	if _, err := db.Exec(`CREATE TABLE speedtest_users (
+		id INTEGER PRIMARY KEY AUTOINCREMENT,
+		timestamp DATETIME, ip TEXT, ispinfo TEXT, extra TEXT,
+		ua TEXT, lang TEXT, dl REAL, ul REAL, ping REAL, jitter REAL, log TEXT)`); err != nil {
+		t.Fatal(err)
+	}
+
+	extra, _ := json.Marshal(map[string]string{"node": "fl", "country": "RU"})
+	// NULL timestamp
+	if _, err := db.Exec(`INSERT INTO speedtest_users(timestamp, extra, dl, ul, ping, jitter)
+		VALUES(NULL, ?, 1, 1, 1, 1)`, string(extra)); err != nil {
+		t.Fatal(err)
+	}
+
+	rows, err := extractRows(context.Background(), db, 0)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(rows) != 0 {
+		t.Errorf("expected 0 rows (null timestamp skipped), got %d", len(rows))
+	}
+}