HKUDS/Vibe-Trading · error · HTTPException

Missing filename

Error message

Missing filename

What it means

The upload endpoint requires a multipart file part with a filename. FastAPI reports file.filename as empty when the client sends a file part without a filename attribute, so the request is rejected with 400.

Source

Thrown at agent/src/api/uploads_routes.py:128

            raise HTTPException(status_code=404, detail=f"Shadow report not found: {shadow_id}.{format}")

        media_type = "text/html; charset=utf-8" if format == "html" else "application/pdf"
        return FileResponse(
            path,
            media_type=media_type,
            headers={"Content-Disposition": f'inline; filename="{shadow_id}.{format}"'},
        )

    @app.post("/upload", dependencies=[Depends(require_auth)])
    async def upload_file(file: UploadFile):
        """Upload any document or data file (max 50MB).

        Accepts most common formats: PDF, Word, Excel, PowerPoint, images,
        CSV/TSV, plain text, JSON, and TOML. Executables, executable-adjacent
        source/config/template files, and archives are rejected.
        """
        if not file.filename:
            raise HTTPException(status_code=400, detail="Missing filename")
        filename = Path(file.filename).name
        ext = Path(filename).suffix.lower()
        if ext in _BLOCKED_UPLOAD_EXT or filename.lower() in _BLOCKED_UPLOAD_NAMES:
            raise HTTPException(
                status_code=400,
                detail="This file type is not allowed for upload.",
            )

        uploads_dir = _host_uploads_dir()
        max_size = _host_max_upload_size()
        chunk_size = _host_chunk_size()

        safe_name = f"{uuid.uuid4().hex}{ext}"
        dest = uploads_dir / safe_name
        total_size = 0

        try:
            uploads_dir.mkdir(parents=True, exist_ok=True)

View on GitHub (pinned to 80ffdda44c)

Solutions

1. Send multipart/form-data with a named file: curl -F 'file=@report.pdf'
2. In JS: formData.append('file', blob, 'report.pdf') — include the third filename argument
3. Verify the field name matches what the endpoint expects

Example fix

// before
formData.append('file', blob)  // no filename in some clients
// after
formData.append('file', blob, 'report.pdf')

if not file_name: raise ValueError('multipart part needs a filename')

def has_filename(fd) -> bool:
    return bool(getattr(fd, 'filename', None))

When it happens

Trigger: POST /uploads with a multipart part named correctly but lacking filename=, or sending raw body/JSON instead of multipart/form-data.

Common situations: Hand-crafted curl requests, fetch/axios calls where the FormData was built incorrectly, or a proxy stripping the filename from the Content-Disposition header.

Related errors

• exit_threshold must be below enter_threshold
• invalid shadow_id
• format must be html or pdf
• This file type is not allowed for upload.
• invalid alpha_id

AI-assisted analysis of HKUDS/Vibe-Trading@80ffdda44c (2026-08-28). Data as JSON: /api/errors/2de661d08883d885. Report an issue: GitHub.