{"record":{"id":"7b593cffa48751f8","repo":"odysseus-dev/odysseus","slug":"signature-png-is-empty","errorCode":null,"errorMessage":"Signature PNG is empty","messagePattern":"Signature PNG is empty","errorType":"http","errorClass":"HTTPException","httpStatus":400,"severity":"error","filePath":"routes/signature_routes.py","lineNumber":48,"sourceCode":"\n\ndef _normalize_signature_png(raw: str) -> str:\n    raw = (raw or \"\").strip()\n    m = _DATA_URL_RE.match(raw)\n    if m:\n        b64 = m.group(\"data\")\n    elif _ANY_IMAGE_DATA_URL_RE.match(raw):\n        raise HTTPException(400, \"Signature data must be a PNG image\")\n    else:\n        b64 = raw\n    if len(b64) > _MAX_SIGNATURE_B64:\n        raise HTTPException(400, \"Signature PNG is too large\")\n    try:\n        payload = base64.b64decode(b64, validate=True)\n    except Exception:\n        raise HTTPException(400, \"Signature data must be base64-encoded PNG bytes\")\n    if not payload:\n        raise HTTPException(400, \"Signature PNG is empty\")\n    if len(payload) > _MAX_SIGNATURE_BYTES:\n        raise HTTPException(400, \"Signature PNG is too large\")\n    if not payload.startswith(_PNG_MAGIC):\n        raise HTTPException(400, \"Signature data must be a PNG image\")\n    return base64.b64encode(payload).decode(\"ascii\")\n\n\ndef _signature_dimension(value: Optional[int]) -> Optional[int]:\n    if value is None:\n        return None\n    if not isinstance(value, int) or value < 1 or value > _MAX_SIGNATURE_DIMENSION:\n        raise HTTPException(400, \"Signature dimensions are invalid\")\n    return value\n\n\nclass SignatureCreate(BaseModel):\n    name: Optional[str] = None\n    data: str  # base64 PNG, with or without `data:image/png;base64,` prefix","sourceCodeStart":30,"sourceCodeEnd":66,"githubUrl":"https://github.com/odysseus-dev/odysseus/blob/f9235ebbf13f693a6fd29ce70b097f6ec83705bf/routes/signature_routes.py#L30-L66","documentation":"Error \"Signature PNG is empty\" thrown in odysseus-dev/odysseus.","triggerScenarios":"Triggered when the corresponding server-side validation or runtime check at the recorded location rejects the request or operation and returns this error message to the caller.","commonSituations":"See trigger scenarios.","solutions":["Draw a signature before saving; the canvas was empty.","Verify the captured PNG contains image data."],"exampleFix":null,"handlingStrategy":null,"validationCode":null,"typeGuard":null,"tryCatchPattern":null,"preventionTips":[],"tags":[],"backgroundTag":null,"analyzedSha":"f9235ebbf13f693a6fd29ce70b097f6ec83705bf","analyzedAt":"2026-08-14T21:47:48.359Z","schemaVersion":2},"datasetVersion":"2026-08-15T22:17:37.221Z"}