samredai commented on a change in pull request #4081: URL: https://github.com/apache/iceberg/pull/4081#discussion_r810664603
########## File path: python/src/iceberg/io/pyarrow.py ########## @@ -0,0 +1,154 @@ +# Licensed to the Apache Software Foundation (ASF) under one +# or more contributor license agreements. See the NOTICE file +# distributed with this work for additional information +# regarding copyright ownership. The ASF licenses this file +# to you under the Apache License, Version 2.0 (the +# "License"); you may not use this file except in compliance +# with the License. You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, +# software distributed under the License is distributed on an +# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +# KIND, either express or implied. See the License for the +# specific language governing permissions and limitations +# under the License. +"""FileIO implementation for reading and writing table files that uses pyarrow.fs + +This file contains a FileIO implementation that relies on the filesystem interface provided +by PyArrow. It relies on PyArrow's `from_uri` method that infers the correct filesystem +type to use. Theoretically, this allows the supported storage types to grow naturally +with the pyarrow library. +""" + +import os +from typing import Union +from urllib.parse import urlparse + +from pyarrow.fs import FileSystem, FileType + +from iceberg.io.base import FileIO, InputFile, InputStream, OutputFile, OutputStream + + +class PyArrowFile(InputFile, OutputFile): + """A combined InputFile and OutputFile implementation that uses a pyarrow filesystem to generate pyarrow.lib.NativeFile instances + + Args: + location(str): A URI or a path to a local file + + Attributes: + location(str): The URI or path to a local file for a PyArrowFile instance + exists(bool): Whether the file exists or not + filesystem(pyarrow.fs.FileSystem): An implementation of the FileSystem base class inferred from the location + + Examples: + >>> from iceberg.io.pyarrow import PyArrowFile + >>> input_file = PyArrowFile("s3://foo/bar.txt") + >>> file_content = input_file.open().read() # Read the contents of the PyArrowFile instance + >>> output_file = PyArrowFile("s3://baz/qux.txt") + >>> output_file.create().write(b'foobytes') # Write bytes to the PyArrowFile instance + """ + + def __init__(self, location: str): + parsed_location = urlparse(location) # Create a ParseResult from the uri + if not parsed_location.scheme: # If no scheme, assume the path is to a local file + self._filesystem, self._path = FileSystem.from_uri(os.path.abspath(location)) + else: + self._filesystem, self._path = FileSystem.from_uri(location) # Infer the proper filesystem + super().__init__(location=location) + + def __len__(self) -> int: + """Returns the total length of the file, in bytes""" + file = self._filesystem.open_input_file(self._path) + return file.size() + + @property + def exists(self) -> bool: + """Checks whether the file exists""" Review comment: [Updated](https://github.com/apache/iceberg/pull/4081/commits/8198bfd8d791957b8858cc838d73e90b38ffc58e) this to say "Checks whether the location exists" which makes more sense generally because the attribute is named `location`. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
