# 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.
# Miscellaneous utility code
import contextlib
import functools
import pathlib
import socket
import warnings
_DEPR_MSG = (
"pyarrow.{} is deprecated as of {}, please use pyarrow.{} instead."
)
def implements(f):
def decorator(g):
g.__doc__ = f.__doc__
return g
return decorator
def _deprecate_api(old_name, new_name, api, next_version):
msg = _DEPR_MSG.format(old_name, next_version, new_name)
def wrapper(*args, **kwargs):
warnings.warn(msg, FutureWarning)
return api(*args, **kwargs)
return wrapper
def _deprecate_class(old_name, new_class, next_version,
instancecheck=True):
"""
Raise warning if a deprecated class is used in an isinstance check.
"""
class _DeprecatedMeta(type):
def __instancecheck__(self, other):
warnings.warn(
_DEPR_MSG.format(old_name, next_version, new_class.__name__),
FutureWarning,
stacklevel=2
)
return isinstance(other, new_class)
return _DeprecatedMeta(old_name, (new_class,), {})
def _is_path_like(path):
# PEP519 filesystem path protocol is available from python 3.6, so pathlib
# doesn't implement __fspath__ for earlier versions
return (isinstance(path, str) or
hasattr(path, '__fspath__') or
isinstance(path, pathlib.Path))
def _stringify_path(path):
"""
Convert *path* to a string or unicode path if possible.
"""
if isinstance(path, str):
return path
# checking whether path implements the filesystem protocol
try:
return path.__fspath__() # new in python 3.6
except AttributeError:
# fallback pathlib ckeck for earlier python versions than 3.6
if isinstance(path, pathlib.Path):
return str(path)
raise TypeError("not a path-like object")
def product(seq):
"""
Return a product of sequence items.
"""
return functools.reduce(lambda a, b: a*b, seq, 1)
def get_contiguous_span(shape, strides, itemsize):
"""
Return a contiguous span of N-D array data.
Parameters
----------
shape : tuple
strides : tuple
itemsize : int
Specify array shape data
Returns
-------
start, end : int
The span end points.
"""
if not strides:
start = 0
end = itemsize * product(shape)
else:
start = 0
end = itemsize
for i, dim in enumerate(shape):
if dim == 0:
start = end = 0
break
stride = strides[i]
if stride > 0:
end += stride * (dim - 1)
elif stride < 0:
start += stride * (dim - 1)
if end - start != itemsize * product(shape):
raise ValueError('array data is non-contiguous')
return start, end
def find_free_port():
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
with contextlib.closing(sock) as sock:
sock.bind(('', 0))
sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
return sock.getsockname()[1]
def guid():
from uuid import uuid4
return uuid4().hex