tryServe method

Future<bool> tryServe(Request req, Response res)

Attempts to serve a file matching the request path.

Implementation

Future<bool> tryServe(Request req, Response res) async {
  if (req.method != 'GET') return false;

  String safePath;
  try {
    safePath = Uri.decodeComponent(req.path);
  } catch (_) {
    return false;
  }

  if (safePath == '/' || safePath.isEmpty) {
    safePath = 'index.html';
  }

  if (safePath.startsWith('/')) {
    safePath = safePath.substring(1);
  }

  final normalizedPath = p.normalize(safePath);
  if (p.isAbsolute(normalizedPath) ||
      p.split(normalizedPath).contains('..')) {
    return false;
  }

  final String fullPath = p.normalize(p.join(_rootDirectory, normalizedPath));
  if (!_isWithinStaticRoot(fullPath)) {
    return false;
  }

  final File file = File(fullPath);

  if (!await file.exists()) return false;

  final stat = await file.stat();
  if (stat.type != FileSystemEntityType.file) {
    return false;
  }

  try {
    final mimeType = lookupMimeType(file.path) ?? 'application/octet-stream';
    res.raw.response.headers.contentType = ContentType.parse(mimeType);

    // Add caching headers for better performance
    // Cache for 1 hour by default
    res.raw.response.headers.add(
      HttpHeaders.cacheControlHeader,
      'public, max-age=3600',
    );

    // Add Last-Modified header
    final lastModified = await file.lastModified();
    res.raw.response.headers.add(
      HttpHeaders.lastModifiedHeader,
      HttpDate.format(lastModified),
    );

    // Check If-Modified-Since
    final ifModifiedSince = req.raw.headers.value(
      HttpHeaders.ifModifiedSinceHeader,
    );
    if (ifModifiedSince != null) {
      try {
        final ifModifiedDate = HttpDate.parse(ifModifiedSince);
        if (lastModified.isBefore(ifModifiedDate) ||
            lastModified.isAtSameMomentAs(ifModifiedDate)) {
          res.raw.response.statusCode = HttpStatus.notModified;
          await res.raw.response.close();
          return true;
        }
      } catch (_) {
        // Ignore parsing errors
      }
    }

    await res.raw.response.addStream(file.openRead());
    await res.raw.response.close();
    return true;
  } catch (_) {
    return false;
  }
}