Function downloadHandler

packages/server/src/routes/fs.ts:211–302

(
    req,
    reply,
  )

  );

  const downloadHandler: Parameters<FsRouteHost['get']>[2] = async (
    req,
    reply,
  ) => {
    const { session_id } = req.params as { session_id: string };
    const wildcard = (req.params as Record<string, unknown>)['*'] as string;

    const DOWNLOAD_SUFFIX = ':download';
    if (!wildcard.endsWith(DOWNLOAD_SUFFIX)) {
      return reply.send(
        errEnvelope(
          ErrorCode.VALIDATION_FAILED,
          `unsupported action: ${wildcard}`,
          req.id,
        ),
      );
    }
    const relPath = wildcard.slice(0, -DOWNLOAD_SUFFIX.length);
    if (relPath.length === 0) {
      return reply.send(
        errEnvelope(
          ErrorCode.VALIDATION_FAILED,
          'path is empty',
          req.id,
        ),
      );
    }

    let resolved: import('@moonshot-ai/agent-core').FsDownloadResolved;
    try {
      resolved = await ix.invokeFunction((a) =>
        a.get(IFsService).resolveDownload(session_id, relPath),
      );
    } catch (err) {
      sendMappedError(reply, req.id, err);
      return reply;
    }

    const ifNoneMatch = pickHeader(req.headers, 'if-none-match');
    if (ifNoneMatch !== undefined && ifNoneMatch === resolved.etag) {
      return reply.code(304).header('etag', resolved.etag).send('');
    }

    reply.header('etag', resolved.etag);
    reply.header(
      'last-modified',
      resolved.modifiedAt.toUTCString(),
    );
    reply.header(
      'content-disposition',
      `attachment; filename="${sanitizeFilename(resolved.relative)}"`,
    );
    reply.type(resolved.mime);

    const rangeHeader = pickHeader(req.headers, 'range');
    const range = parseRangeHeader(rangeHeader, resolved.size);
    if (range !== null) {
      reply