80 lines
2.4 KiB
Python
80 lines
2.4 KiB
Python
"""
|
|
pkgdata is a simple, extensible way for a package to acquire data file
|
|
resources.
|
|
|
|
The getResource function is equivalent to the standard idioms, such as
|
|
the following minimal implementation:
|
|
|
|
import sys, os
|
|
|
|
def getResource(identifier, pkgname=__name__):
|
|
pkgpath = os.path.dirname(sys.modules[pkgname].__file__)
|
|
path = os.path.join(pkgpath, identifier)
|
|
return file(os.path.normpath(path), mode='rb')
|
|
|
|
When a __loader__ is present on the module given by __name__, it will defer
|
|
getResource to its get_data implementation and return it as a file-like
|
|
object (such as StringIO).
|
|
"""
|
|
|
|
__all__ = ["getResource"]
|
|
import sys
|
|
import os
|
|
|
|
from io import BytesIO
|
|
|
|
try:
|
|
from pkg_resources import resource_stream, resource_exists
|
|
except ImportError:
|
|
|
|
def resource_exists(_package_or_requirement, _resource_name):
|
|
"""
|
|
A stub for when we fail to import this function.
|
|
|
|
:return: Always returns False
|
|
"""
|
|
return False
|
|
|
|
def resource_stream(_package_of_requirement, _resource_name):
|
|
"""
|
|
A stub for when we fail to import this function.
|
|
|
|
Always raises a NotImplementedError when called.
|
|
"""
|
|
raise NotImplementedError
|
|
|
|
|
|
def getResource(identifier, pkgname=__name__):
|
|
"""
|
|
Acquire a readable object for a given package name and identifier.
|
|
An IOError will be raised if the resource can not be found.
|
|
|
|
For example:
|
|
mydata = getResource('mypkgdata.jpg').read()
|
|
|
|
Note that the package name must be fully qualified, if given, such
|
|
that it would be found in sys.modules.
|
|
|
|
In some cases, getResource will return a real file object. In that
|
|
case, it may be useful to use its name attribute to get the path
|
|
rather than use it as a file-like object. For example, you may
|
|
be handing data off to a C API.
|
|
"""
|
|
|
|
# When pyinstaller (or similar tools) are used, resource_exists may raise
|
|
# NotImplemented error
|
|
try:
|
|
if resource_exists(pkgname, identifier):
|
|
return resource_stream(pkgname, identifier)
|
|
except NotImplementedError:
|
|
pass
|
|
|
|
mod = sys.modules[pkgname]
|
|
path_to_file = getattr(mod, "__file__", None)
|
|
if path_to_file is None:
|
|
raise IOError(f"{repr(mod)} has no __file__!")
|
|
path = os.path.join(os.path.dirname(path_to_file), identifier)
|
|
|
|
# pylint: disable=consider-using-with
|
|
return open(os.path.normpath(path), "rb")
|