pyarrow.NativeFile

class pyarrow.NativeFile

Bases: object

The base class for all Arrow streams.

Streams are either readable, writable, or both. They optionally support seeking.

While this class exposes methods to read or write data from Python, the primary intent of using a Arrow stream is to pass it to other Arrow facilities that will make use of it, such as Arrow IPC routines.

__init__()

Initialize self. See help(type(self)) for accurate signature.

Methods

close(self)
download(self, stream_or_path[, buffer_size]) Read file completely to local path (rather than reading completely into memory).
fileno(self) NOT IMPLEMENTED
flush(self) Flush the buffer stream, if applicable.
isatty(self)
read(self[, nbytes]) Read indicated number of bytes from file, or read all remaining bytes if no argument passed
read1(self[, nbytes]) Read and return up to n bytes.
read_buffer(self[, nbytes])
readable(self)
readall(self)
readinto(self, b) Read into the supplied buffer
readline(self[, size]) NOT IMPLEMENTED.
readlines(self[, hint]) NOT IMPLEMENTED.
seek(self, int64_t position, int whence=0) Change current file stream position
seekable(self)
size(self) Return file size
tell(self) Return current stream position
truncate(self) NOT IMPLEMENTED
upload(self, stream[, buffer_size]) Pipe file-like object to file
writable(self)
write(self, data) Write byte from any object implementing buffer protocol (bytes, bytearray, ndarray, pyarrow.Buffer)
writelines(self, lines)

Attributes

closed
mode binary read * wb: binary write * rb+: binary read and write
close(self)
closed
download(self, stream_or_path, buffer_size=None)

Read file completely to local path (rather than reading completely into memory). First seeks to the beginning of the file.

fileno(self)

NOT IMPLEMENTED

flush(self)

Flush the buffer stream, if applicable.

No-op to match the IOBase interface.

isatty(self)
mode

binary read * wb: binary write * rb+: binary read and write

Type:

The file mode. Currently instances of NativeFile may support
Type:
  • rb
read(self, nbytes=None)

Read indicated number of bytes from file, or read all remaining bytes if no argument passed

Parameters:nbytes (int, default None) –
Returns:data (bytes)
read1(self, nbytes=None)

Read and return up to n bytes.

Alias for read, needed to match the IOBase interface.

read_buffer(self, nbytes=None)
readable(self)
readall(self)
readinto(self, b)

Read into the supplied buffer

Parameters:b (any python object supporting buffer interface) –
Returns:number of bytes written
readline(self, size=None)

NOT IMPLEMENTED. Read and return a line of bytes from the file.

If size is specified, read at most size bytes.

Line terminator is always b”n”.

readlines(self, hint=None)

NOT IMPLEMENTED. Read lines of the file

Parameters:hint (int maximum number of bytes read until we stop) –
seek(self, int64_t position, int whence=0)

Change current file stream position

Parameters:
  • position (int) – Byte offset, interpreted relative to value of whence argument
  • whence (int, default 0) – Point of reference for seek offset

Notes

Values of whence: * 0 – start of stream (the default); offset should be zero or positive * 1 – current stream position; offset may be negative * 2 – end of stream; offset is usually negative

Returns:new_position (the new absolute stream position)
seekable(self)
size(self)

Return file size

tell(self)

Return current stream position

truncate(self)

NOT IMPLEMENTED

upload(self, stream, buffer_size=None)

Pipe file-like object to file

writable(self)
write(self, data)

Write byte from any object implementing buffer protocol (bytes, bytearray, ndarray, pyarrow.Buffer)

Parameters:data (bytes-like object or exporter of buffer protocol) –
Returns:nbytes (number of bytes written)
writelines(self, lines)