fix: UDP-logged QSOs fall back to the offline outbox on DB failure (were silently lost); speed up MySQL connect (batch migration checks into 1 query, connect direct-to-DB first) — was ~40s on a high-latency link

app.go

@@ -9623,6 +9623,14 @@ func (a *App) LogUDPLoggedADIF(adifText string) (int64, error) {
 
 	id, err := a.qso.Add(a.ctx, q)
 	if err != nil {
+		// DB UNREACHABLE (drop / timeout on a slow-or-broken MySQL) — park the QSO
+		// in the offline outbox rather than lose it, exactly like the manual log
+		// path. Without this, a laggy shared MySQL silently dropped UDP-logged QSOs
+		// from a multi-stream MSHV. Returns -1 so the caller treats it as "saved,
+		// waiting to sync", not a failure.
+		if db.IsConnLost(err) && a.queueOffline(q, err) {
+			return -1, nil
+		}
 		return 0, fmt.Errorf("insert qso: %w", err)
 	}
 	q.ID = id
@@ -9633,6 +9641,10 @@ func (a *App) LogUDPLoggedADIF(adifText string) (int64, error) {
 		a.extsvc.OnQSOLogged(id)
 	}
 	a.maybeAutoSendEQSL(q)
+	// A successful write means the link is healthy again — flush anything parked.
+	if a.offlineMode && a.offlineQ != nil && a.offlineQ.Count() > 0 {
+		go func() { _, _ = a.replayOfflineQueue() }()
+	}
 	return id, nil
 }
 

internal/db/db.go

@@ -198,14 +198,26 @@ func migrate(conn *sql.DB, translate func(string) string) error {
 	}
 	sort.Strings(names)
 
-	for _, name := range names {
-		var dummy string
-		err := conn.QueryRow(`SELECT name FROM schema_migrations WHERE name = ?`, name).Scan(&dummy)
-		if err == nil {
-			continue // already applied
+	// Fetch every applied migration name in ONE query rather than one round-trip
+	// per migration. On a high-latency remote MySQL those 20+ SELECTs dominated the
+	// connect time (each RTT × migration count) — the whole logbook connect could
+	// take tens of seconds. One SELECT + an in-memory set is effectively instant.
+	applied := map[string]bool{}
+	if rows, err := conn.Query(`SELECT name FROM schema_migrations`); err == nil {
+		for rows.Next() {
+			var n string
+			if rows.Scan(&n) == nil {
+				applied[n] = true
+			}
 		}
-		if err != sql.ErrNoRows {
-			return fmt.Errorf("check migration %s: %w", name, err)
+		rows.Close()
+	} else {
+		return fmt.Errorf("read applied migrations: %w", err)
+	}
+
+	for _, name := range names {
+		if applied[name] {
+			continue // already applied
 		}
 		content, err := migrationsFS.ReadFile("migrations/" + name)
 		if err != nil {

internal/db/mysql.go

@@ -137,10 +137,6 @@ func OpenMySQL(c MySQLConfig) (*sql.DB, error) {
 	if !validDBIdent(name) {
 		return nil, fmt.Errorf("invalid database name %q (letters, digits, underscore only)", name)
 	}
-	// Ensure the database exists (connect server-level first).
-	if err := PingMySQL(c); err != nil {
-		return nil, err
-	}
 	conn, err := sql.Open("mysql", c.dsn())
 	if err != nil {
 		return nil, fmt.Errorf("open mysql: %w", err)
@@ -157,9 +153,28 @@ func OpenMySQL(c MySQLConfig) (*sql.DB, error) {
 	// (surfacing as "Unknown database"). Idle connections are still recycled
 	// after 90s, and the driver retries stale pooled connections.
 	conn.SetConnMaxLifetime(0)
+	// Connect DIRECTLY to the database first. Only if that fails — the DB doesn't
+	// exist yet (first-time setup) or the server is unreachable — do we pay for the
+	// server-level connect + CREATE DATABASE (two more handshakes). On a normal
+	// startup against an existing DB this halves the connection round-trips, which
+	// matters a lot on a high-latency remote MySQL (each handshake is several RTTs).
 	if err := conn.Ping(); err != nil {
 		_ = conn.Close()
-		return nil, fmt.Errorf("connect to %s: %w", name, err)
+		if perr := PingMySQL(c); perr != nil {
+			return nil, perr // creates the DB (or returns a clear "cannot create" error)
+		}
+		conn, err = sql.Open("mysql", c.dsn())
+		if err != nil {
+			return nil, fmt.Errorf("open mysql: %w", err)
+		}
+		conn.SetMaxOpenConns(50)
+		conn.SetMaxIdleConns(10)
+		conn.SetConnMaxIdleTime(90 * time.Second)
+		conn.SetConnMaxLifetime(0)
+		if err := conn.Ping(); err != nil {
+			_ = conn.Close()
+			return nil, fmt.Errorf("connect to %s: %w", name, err)
+		}
 	}
 	// Set the dialect before migrating so the runner takes the MySQL path
 	// (per-statement, idempotent) rather than the SQLite transaction path.