langflow-ai/langflow · error · HTTPException

No files provided

Error message

No files provided

What it means

Error "No files provided" thrown in langflow-ai/langflow.

Source

Thrown at src/backend/base/langflow/api/v1/knowledge_bases.py:904

    files: Annotated[list[UploadFile], File(description="Files to preview chunking for")],
    # Upper bounds cap the memory footprint of a preview request.
    # ``max_chunks * chunk_size * CHUNK_PREVIEW_MULTIPLIER`` is the
    # largest text slice this endpoint will hold in memory — without
    # these bounds, an authenticated user can request gigabytes.
    chunk_size: Annotated[int, Form(ge=MIN_CHUNK_SIZE, le=MAX_CHUNK_SIZE)] = 1000,
    chunk_overlap: Annotated[int, Form(ge=MIN_CHUNK_OVERLAP, le=MAX_CHUNK_OVERLAP)] = 200,
    separator: Annotated[str, Form()] = "\n",
    max_chunks: Annotated[int, Form(ge=MIN_MAX_CHUNKS, le=MAX_MAX_CHUNKS)] = 5,
) -> dict[str, object]:
    """Preview how files will be chunked without storing anything.

    Uses the same RecursiveCharacterTextSplitter as the ingest endpoint
    so the preview accurately reflects what will be stored.
    """
    await _guard_kb_action(current_user=current_user, action=KnowledgeBaseAction.CREATE, kb_name=None)
    try:
        if not files:
            raise HTTPException(status_code=400, detail="No files provided")

        # Build separators list: user separator first, then defaults
        separators = None
        if separator:
            # Unescape common escape sequences
            actual_separator = separator.replace("\\n", "\n").replace("\\t", "\t")
            separators = [actual_separator, "\n\n", "\n", " ", ""]

        text_splitter = RecursiveCharacterTextSplitter(
            chunk_size=chunk_size,
            chunk_overlap=chunk_overlap,
            separators=separators,
        )

        file_previews: list[dict[str, Any]] = []
        for uploaded_file in files:
            try:
                file_content = await uploaded_file.read()

View on GitHub (pinned to 976ec789d2)

Solutions

1. Attach at least one file to the upload request.

When it happens

Trigger: Occurs when an ingestion or preview request to a knowledge base arrives without any attached files.

Common situations: See trigger scenarios.

AI-assisted analysis of langflow-ai/langflow@976ec789d2 (2026-08-14). Data as JSON: /api/errors/578248a35879663a. Report an issue: GitHub.