ray.data.read_json#

ray.data.read_json(paths: Union[str, List[str]], *, filesystem: Optional[pyarrow.fs.FileSystem] = None, parallelism: int = -1, ray_remote_args: Dict[str, Any] = None, arrow_open_stream_args: Optional[Dict[str, Any]] = None, meta_provider: ray.data.datasource.file_meta_provider.BaseFileMetadataProvider = <ray.data.datasource.file_meta_provider.DefaultFileMetadataProvider object>, partition_filter: Optional[ray.data.datasource.partitioning.PathPartitionFilter] = FileExtensionFilter(extensions=['.json'], allow_if_no_extensions=False), partitioning: ray.data.datasource.partitioning.Partitioning = Partitioning(style='hive', base_dir='', field_names=None, filesystem=None), **arrow_json_args) ray.data.dataset.Dataset[ray.data._internal.arrow_block.ArrowRow][source]#

Create an Arrow dataset from json files.

Examples

>>> import ray
>>> # Read a directory of files in remote storage.
>>> ray.data.read_json("s3://bucket/path") 
>>> # Read multiple local files.
>>> ray.data.read_json(["/path/to/file1", "/path/to/file2"]) 
>>> # Read multiple directories.
>>> ray.data.read_json( 
...     ["s3://bucket/path1", "s3://bucket/path2"])

By default, read_json parses Hive-style partitions from file paths. If your data adheres to a different partitioning scheme, set the partitioning parameter.

>>> ds = ray.data.read_json("example://year=2022/month=09/sales.json")  
>>> ds.take(1)  
[{'order_number': 10107, 'quantity': 30, 'year': '2022', 'month': '09'}
Parameters
  • paths – A single file/directory path or a list of file/directory paths. A list of paths can contain both files and directories.

  • filesystem – The filesystem implementation to read from.

  • parallelism – The requested parallelism of the read. Parallelism may be limited by the number of files of the dataset.

  • ray_remote_args – kwargs passed to ray.remote in the read tasks.

  • arrow_open_stream_args – kwargs passed to pyarrow.fs.FileSystem.open_input_stream

  • meta_provider – File metadata provider. Custom metadata providers may be able to resolve file metadata more quickly and/or accurately.

  • partition_filter – Path-based partition filter, if any. Can be used with a custom callback to read only selected partitions of a dataset. By default, this filters out any file paths whose file extension does not match “.json”.

  • arrow_json_args – Other json read options to pass to pyarrow.

  • partitioning

    A Partitioning object that describes how paths are organized. By default, this function parses Hive-style partitions.

Returns

Dataset holding Arrow records read from the specified paths.

PublicAPI: This API is stable across Ray releases.