## wiring.file_writer()


Return a writer that writes the invalid rows to a parquet file under `quarantine_dir`.


Usage

``` python
wiring.file_writer(
    key,
    quarantine_dir,
    partition_key=None,
)
```


Use it in a direct invocation, where [delegating_writer](wiring.delegating_writer.md#dagster_dataframely.wiring.delegating_writer) raises because there is no step. The file is at `quarantine_path(key, quarantine_dir, partition_key)`.


## Parameters


`key: dg.AssetKey`  
The asset key of the asset whose rows failed validation, not the quarantine's key.


## Returns


`A writer that takes the invalid rows and returns the file's path as a string.`