What causes "Error fetching transformation: {str(e)}" in lfnovo/open-notebook?

Check API logs for the underlying exception message

lfnovo/open-notebook · error · HTTPException

Error fetching transformation: {str(e)}

Error message

Error fetching transformation: {str(e)}

What it means

Generic 500 from GET /transformations/{transformation_id} when fetching the record raises an unexpected exception (i.e. not the clean not-found case). Typically a SurrealDB query error or record deserialization problem inside Transformation.get.

Source

Thrown at api/routers/transformations.py:202

@router.get(
    "/transformations/{transformation_id}", response_model=TransformationResponse
)
async def get_transformation(transformation_id: str):
    """Get a specific transformation by ID."""
    try:
        transformation = await Transformation.get(transformation_id)
        if not transformation:
            raise HTTPException(status_code=404, detail="Transformation not found")

        return _transformation_response(transformation)
    except HTTPException:
        raise
    except OpenNotebookError:
        raise
    except Exception as e:
        logger.error(f"Error fetching transformation {transformation_id}: {str(e)}")
        raise HTTPException(
            status_code=500, detail=f"Error fetching transformation: {str(e)}"
        )


@router.put(
    "/transformations/{transformation_id}", response_model=TransformationResponse
)
async def update_transformation(
    transformation_id: str, transformation_update: TransformationUpdate
):
    """Update a transformation."""
    try:
        transformation = await Transformation.get(transformation_id)
        if not transformation:
            raise HTTPException(status_code=404, detail="Transformation not found")

        # Update only provided fields
        if transformation_update.name is not None:

View on GitHub (pinned to a7de90d38a)

Solutions

Check API logs for the underlying exception message
Confirm the ID format matches existing transformation IDs (compare with GET /transformations output)
Verify SurrealDB is reachable and restart the API if the connection pool went stale

Defensive patterns

Strategy: try-catch

Validate before calling

def looks_like_record_id(rid: str) -> bool:
    return bool(rid) and ':' in rid

Try / catch

resp = await client.get(f'/transformations/{tid}')
if resp.status_code == 500:
    logger.error('fetch failed', resp.json().get('detail'))
    # verify DB health before retrying
if resp.status_code == 404:
    ...  # genuine not-found

Prevention

Use full record IDs (table:id) as returned by the API
Distinguish 404 (bad ID) from 500 (infrastructure) in error handling
Check API logs for the root exception

When it happens

Trigger: GET /api/transformations/{id} with a malformed record ID that crashes the SurrealDB query parser, or while the database connection has dropped.

Common situations: Passing a raw ID without the record prefix, a SurrealDB restart mid-session, or version drift between the model class and stored records.

Related errors

AI-assisted analysis of lfnovo/open-notebook@a7de90d38a (2026-08-27). Data as JSON: /api/errors/d06cb5eddb2d9b36. Report an issue: GitHub.