# LOGGING

`LoggingStep` is a pipeline step that simply logs the input data keys (and optionally values) and returns the input data unchanged.

| Configs        | Descriptions                                                                                                                                                               |
| -------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| logLevel       | This is similar to how standard logging frameworks define logging categories. Default value is `INFO`. Another available options are `TRACE`, `DEBUG`, `WARN` and `ERROR`. |
| log            | An enum specifying what part of a data instance should be logged. Default value is `KEYS`.                                                                                 |
| keyFilterRegex | A regular expression that allows filtering of keys - i.e., only those that match the regex will be logged.                                                                 |