def inspect_io_obj(obj):
"""
:param obj: a path string, a pathlib.Path or a file / file-like object
:return: A tuple of (objtype, objpath, objopener)
:raises: UnknownFileTypeError
"""
itype = guess_io_type(obj)
if itype == IOI_PATH_STR:
ipath = anyconfig.utils.normpath(obj)
opener = open
elif itype == IOI_PATH_OBJ:
ipath = anyconfig.utils.normpath(obj.as_posix())
opener = obj.open
elif itype == IOI_STREAM:
ipath = anyconfig.utils.get_path_from_stream(obj)
opener = anyconfig.utils.noop
elif itype == IOI_NONE:
ipath = None
opener = anyconfig.utils.noop
else:
raise UnknownFileTypeError("%r" % obj)
return (itype, ipath, opener)
def find_processor(ipath, cps_by_ext, cps_by_type, forced_type=None):
"""
:param ipath: file path
:param cps_by_ext: A list of pairs (file_extension, [processor_cls])
:param cps_by_type: A list of pairs (processor_type, [processor_cls])
:param forced_type: Forced processor type or processor object
:return: Instance of processor class appropriate for the input `ipath`
:raises: ValueError, UnknownParserTypeError, UnknownFileTypeError
"""
if (ipath is None or not ipath) and forced_type is None:
raise ValueError("ipath or forced_type must be some value")
if isinstance(forced_type, anyconfig.backend.base.Parser):
return forced_type
if forced_type is None:
processor = find_by_filepath(ipath, cps_by_ext)
if processor is None:
raise UnknownFileTypeError(ipath)
return processor()
processor = find_by_type(forced_type, cps_by_type)
if processor is None:
raise UnknownParserTypeError(forced_type)
return processor()
def find(obj, prs, forced_type=None, cls=anyconfig.models.processor.Processor):
"""
:param obj:
a file path, file or file-like object, pathlib.Path object or
`~anyconfig.globals.IOInfo` (namedtuple) object
:param prs: A list of :class:`anyconfig.models.processor.Processor` classes
:param forced_type: Forced processor type or processor object itself
:param cls: A class object to compare with `forced_type` later
:return: an instance of processor class to process `obj` data
:raises: ValueError, UnknownProcessorTypeError, UnknownFileTypeError
"""
if (obj is None or not obj) and forced_type is None:
raise ValueError("The first argument 'obj' or the second argument "
"'forced_type' must be something other than "
"None or False.")
if forced_type is None:
processor = find_by_maybe_file(obj, prs)
if processor is None:
raise UnknownFileTypeError(obj)
return processor
processor = find_by_type(forced_type, prs, cls=cls)
if processor is None:
raise UnknownProcessorTypeError(forced_type)
return processor
def find_by_fileext(fileext, prs):
"""
:param fileext: File extension
:param prs: A list of :class:`anyconfig.models.processor.Processor` classes
:return: A list of processor class to processor files with given extension
:raises: UnknownFileTypeError
"""
def pred(pcls):
"""Predicate"""
return fileext in pcls.extensions()
pclss = findall_with_pred(pred, prs)
if not pclss:
raise UnknownFileTypeError("file extension={}".format(fileext))
return pclss # :: [Processor], never []
def find_by_maybe_file(obj, prs):
"""
:param obj:
a file path, file or file-like object, pathlib.Path object or
`~anyconfig.globals.IOInfo` (namedtuple) object
:param cps_by_ext: A list of processor classes
:return:
An instance of most appropriate processor class to process given data
:raises: UnknownFileTypeError
"""
if not isinstance(obj, IOInfo):
obj = anyconfig.ioinfo.make(obj)
processor = find_by_fileext(obj.extension, prs)
if processor is None:
raise UnknownFileTypeError("file extension={}".format(obj.extension))
return processor()