# Logging

When you run a migration task, the tools set up logging automatically. You get a Rich-formatted console stream plus log files under the iteration’s `reports/` folder. Third-party libraries (including `folio_data_import`) flow into the same handlers.

## What you see during a run
- Console: Rich output at INFO by default (DEBUG if enabled). Progress output and logs interleave cleanly.
- Files (per task run):
  - `reports/log_<object>_<timestamp>.log` — full run log at INFO/DEBUG.
  - `reports/data_issues_log_<timestamp>.tsv` — only data issues (custom level 26).
- Noise control: `httpx` and `pymarc` are reduced to WARNING so they do not flood the console.

## Turning on DEBUG
- In your configuration (libraryInformation), set `logLevelDebug: true` to enable DEBUG for the run. This raises verbosity for both console and log files.
- Leave it `false` for the default INFO view.

## Where logs land
Logs are written inside the iteration you specify in `libraryInformation.iterationIdentifier`, under `base_folder/iterations/<iteration>/reports/`:
- `log_<object>_<timestamp>.log` — main log
- `data_issues_log_<timestamp>.tsv` — data issues only

## Third-party logs
Handlers are attached at the root logger, so module-level loggers inside dependencies (e.g., `folio_data_import`) are captured automatically. Suppression for chatty libraries remains in place; adjust levels manually if you need more detail.

## Tips for noisy environments
- If you enable DEBUG and see too much from HTTP clients, you can lower them via env or a small shim before invoking the CLI (e.g., set `LOGGING_HTTPX_LEVEL=WARNING` in your wrapper). By default, they are already set to WARNING.