bugfixes

backend/postgres_database.go

@@ -0,0 +1,149 @@
+package main
+
+import (
+	"context"
+	"database/sql"
+	"errors"
+	"fmt"
+	"net/url"
+	"strings"
+	"time"
+)
+
+func ensurePostgresDatabaseExists(dsn string) error {
+	dsn = strings.TrimSpace(dsn)
+	if dsn == "" {
+		return errors.New("databaseUrl ist leer")
+	}
+
+	u, err := url.Parse(dsn)
+	if err != nil {
+		return fmt.Errorf("databaseUrl ungueltig: %w", err)
+	}
+
+	dbName, err := postgresDatabaseNameFromURL(u)
+	if err != nil {
+		return err
+	}
+
+	if err := pingPostgresDSN(u.String()); err == nil {
+		return nil
+	} else if !isMissingPostgresDatabaseError(err) {
+		return err
+	}
+
+	var lastErr error
+	for _, maintenanceDB := range []string{"postgres", "template1"} {
+		if strings.EqualFold(maintenanceDB, dbName) {
+			continue
+		}
+
+		maintenanceURL := *u
+		maintenanceURL.Path = "/" + maintenanceDB
+		maintenanceURL.RawPath = ""
+
+		if err := createPostgresDatabaseIfMissing(maintenanceURL.String(), dbName); err != nil {
+			lastErr = err
+			continue
+		}
+
+		return pingPostgresDSN(u.String())
+	}
+
+	if lastErr != nil {
+		return lastErr
+	}
+	return fmt.Errorf("Datenbank %s existiert nicht und konnte nicht angelegt werden", dbName)
+}
+
+func postgresDatabaseNameFromURL(u *url.URL) (string, error) {
+	if u == nil {
+		return "", errors.New("databaseUrl ist leer")
+	}
+
+	switch strings.ToLower(strings.TrimSpace(u.Scheme)) {
+	case "postgres", "postgresql":
+	default:
+		return "", errors.New("databaseUrl muss postgres:// oder postgresql:// verwenden")
+	}
+
+	dbName, err := url.PathUnescape(strings.TrimPrefix(u.EscapedPath(), "/"))
+	if err != nil {
+		return "", fmt.Errorf("Datenbankname ungueltig: %w", err)
+	}
+	dbName = strings.TrimSpace(dbName)
+	if dbName == "" {
+		return "", errors.New("Datenbankname fehlt in databaseUrl")
+	}
+	if strings.ContainsRune(dbName, 0) {
+		return "", errors.New("Datenbankname enthaelt ungueltige Zeichen")
+	}
+	return dbName, nil
+}
+
+func pingPostgresDSN(dsn string) error {
+	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+	defer cancel()
+
+	db, err := sql.Open("pgx", dsn)
+	if err != nil {
+		return err
+	}
+	defer db.Close()
+
+	return db.PingContext(ctx)
+}
+
+func createPostgresDatabaseIfMissing(maintenanceDSN string, dbName string) error {
+	ctx, cancel := context.WithTimeout(context.Background(), 15*time.Second)
+	defer cancel()
+
+	db, err := sql.Open("pgx", maintenanceDSN)
+	if err != nil {
+		return err
+	}
+	defer db.Close()
+
+	if err := db.PingContext(ctx); err != nil {
+		return err
+	}
+
+	var exists bool
+	if err := db.QueryRowContext(ctx, `SELECT EXISTS (SELECT 1 FROM pg_database WHERE datname=$1)`, dbName).Scan(&exists); err != nil {
+		return err
+	}
+	if exists {
+		return nil
+	}
+
+	_, err = db.ExecContext(ctx, `CREATE DATABASE `+quotePostgresIdentifier(dbName))
+	if err != nil && isDuplicatePostgresDatabaseError(err) {
+		return nil
+	}
+	return err
+}
+
+func quotePostgresIdentifier(v string) string {
+	return `"` + strings.ReplaceAll(v, `"`, `""`) + `"`
+}
+
+func isMissingPostgresDatabaseError(err error) bool {
+	if err == nil {
+		return false
+	}
+	msg := strings.ToLower(err.Error())
+	return strings.Contains(msg, "sqlstate 3d000") ||
+		strings.Contains(msg, "sqlstate 30000") ||
+		strings.Contains(msg, "database") && strings.Contains(msg, "does not exist") ||
+		strings.Contains(msg, "datenbank") && strings.Contains(msg, "existiert nicht")
+}
+
+func isDuplicatePostgresDatabaseError(err error) bool {
+	if err == nil {
+		return false
+	}
+	msg := strings.ToLower(err.Error())
+	return strings.Contains(msg, "sqlstate 42p04") ||
+		strings.Contains(msg, "already exists") ||
+		strings.Contains(msg, "existiert bereits")
+}

backend/routes.go

@@ -130,6 +130,10 @@ func registerRoutes(mux *http.ServeMux, auth *AuthManager) *ModelStore {
 	}
 	appLogln("Models DB (Postgres):", sanitizeDSNForLog(storeConfig.DSN))
 
+	if err := ensurePostgresDatabaseExists(storeConfig.DSN); err != nil {
+		appLogln("models DB ensure:", err)
+	}
+
 	store := NewModelStore(storeConfig)
 	if err := store.Load(); err != nil {
 		appLogln("⚠️ models load:", err)

backend/settings.go

@@ -568,6 +568,11 @@ func recordSettingsHandler(w http.ResponseWriter, r *http.Request) {
 				return
 			}
 
+			if err := ensurePostgresDatabaseExists(storeConfig.DSN); err != nil {
+				http.Error(w, "Datenbank konnte nicht angelegt/geprueft werden: "+err.Error(), http.StatusBadRequest)
+				return
+			}
+
 			newStore = NewModelStore(storeConfig)
 			if err := newStore.Load(); err != nil {
 				_ = newStore.Close()