Viewing file:  readers.py (3.47 KB) -rw-r--r--
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import collections
import operator
import pathlib
import zipfile
from . import abc
from ._itertools import unique_everseen
def remove_duplicates(items):
return iter(collections.OrderedDict.fromkeys(items))
class FileReader(abc.TraversableResources):
def __init__(self, loader):
self.path = pathlib.Path(loader.path).parent
def resource_path(self, resource):
"""
Return the file system path to prevent
`resources.path()` from creating a temporary
copy.
"""
return str(self.path.joinpath(resource))
def files(self):
return self.path
class ZipReader(abc.TraversableResources):
def __init__(self, loader, module):
_, _, name = module.rpartition('.')
self.prefix = loader.prefix.replace('\\', '/') + name + '/'
self.archive = loader.archive
def open_resource(self, resource):
try:
return super().open_resource(resource)
except KeyError as exc:
raise FileNotFoundError(exc.args[0])
def is_resource(self, path):
# workaround for `zipfile.Path.is_file` returning true
# for non-existent paths.
target = self.files().joinpath(path)
return target.is_file() and target.exists()
def files(self):
return zipfile.Path(self.archive, self.prefix)
class MultiplexedPath(abc.Traversable):
"""
Given a series of Traversable objects, implement a merged
version of the interface across all objects. Useful for
namespace packages which may be multihomed at a single
name.
"""
def __init__(self, *paths):
self._paths = list(map(pathlib.Path, remove_duplicates(paths)))
if not self._paths:
message = 'MultiplexedPath must contain at least one path'
raise FileNotFoundError(message)
if not all(path.is_dir() for path in self._paths):
raise NotADirectoryError('MultiplexedPath only supports directories')
def iterdir(self):
files = (file for path in self._paths for file in path.iterdir())
return unique_everseen(files, key=operator.attrgetter('name'))
def read_bytes(self):
raise FileNotFoundError(f'{self} is not a file')
def read_text(self, *args, **kwargs):
raise FileNotFoundError(f'{self} is not a file')
def is_dir(self):
return True
def is_file(self):
return False
def joinpath(self, child):
# first try to find child in current paths
for file in self.iterdir():
if file.name == child:
return file
# if it does not exist, construct it with the first path
return self._paths[0] / child
__truediv__ = joinpath
def open(self, *args, **kwargs):
raise FileNotFoundError(f'{self} is not a file')
@property
def name(self):
return self._paths[0].name
def __repr__(self):
paths = ', '.join(f"'{path}'" for path in self._paths)
return f'MultiplexedPath({paths})'
class NamespaceReader(abc.TraversableResources):
def __init__(self, namespace_path):
if 'NamespacePath' not in str(namespace_path):
raise ValueError('Invalid path')
self.path = MultiplexedPath(*list(namespace_path))
def resource_path(self, resource):
"""
Return the file system path to prevent
`resources.path()` from creating a temporary
copy.
"""
return str(self.path.joinpath(resource))
def files(self):
return self.path
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