Coverage for python/lsst/daf/butler/core/_butlerUri.py : 16%

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1# This file is part of daf_butler.
2#
3# Developed for the LSST Data Management System.
4# This product includes software developed by the LSST Project
5# (http://www.lsst.org).
6# See the COPYRIGHT file at the top-level directory of this distribution
7# for details of code ownership.
8#
9# This program is free software: you can redistribute it and/or modify
10# it under the terms of the GNU General Public License as published by
11# the Free Software Foundation, either version 3 of the License, or
12# (at your option) any later version.
13#
14# This program is distributed in the hope that it will be useful,
15# but WITHOUT ANY WARRANTY; without even the implied warranty of
16# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17# GNU General Public License for more details.
18#
19# You should have received a copy of the GNU General Public License
20# along with this program. If not, see <http://www.gnu.org/licenses/>.
22from __future__ import annotations
24__all__ = ("ButlerURI",)
26import contextlib
27import os
28import os.path
29import shutil
30import urllib
31import pkg_resources
32import posixpath
33from pathlib import Path, PurePath, PurePosixPath
34import requests
35import tempfile
36import copy
37import logging
38import re
40from typing import (
41 TYPE_CHECKING,
42 Any,
43 Callable,
44 cast,
45 Iterator,
46 Optional,
47 Tuple,
48 Type,
49 Union,
50)
52from .utils import safeMakeDir
54if TYPE_CHECKING: 54 ↛ 55line 54 didn't jump to line 55, because the condition on line 54 was never true
55 try:
56 import boto3
57 except ImportError:
58 pass
59 from .datastore import DatastoreTransaction
62log = logging.getLogger(__name__)
64# Determine if the path separator for the OS looks like POSIX
65IS_POSIX = os.sep == posixpath.sep
67# Root path for this operating system
68OS_ROOT_PATH = Path().resolve().root
70# Regex for looking for URI escapes
71ESCAPES_RE = re.compile(r"%[A-F0-9]{2}")
74def os2posix(ospath: str) -> str:
75 """Convert a local path description to a POSIX path description.
77 Parameters
78 ----------
79 ospath : `str`
80 Path using the local path separator.
82 Returns
83 -------
84 posix : `str`
85 Path using POSIX path separator
86 """
87 if IS_POSIX:
88 return ospath
90 posix = PurePath(ospath).as_posix()
92 # PurePath strips trailing "/" from paths such that you can no
93 # longer tell if a path is meant to be referring to a directory
94 # Try to fix this.
95 if ospath.endswith(os.sep) and not posix.endswith(posixpath.sep):
96 posix += posixpath.sep
98 return posix
101def posix2os(posix: Union[PurePath, str]) -> str:
102 """Convert a POSIX path description to a local path description.
104 Parameters
105 ----------
106 posix : `str`, `PurePath`
107 Path using the POSIX path separator.
109 Returns
110 -------
111 ospath : `str`
112 Path using OS path separator
113 """
114 if IS_POSIX:
115 return str(posix)
117 posixPath = PurePosixPath(posix)
118 paths = list(posixPath.parts)
120 # Have to convert the root directory after splitting
121 if paths[0] == posixPath.root:
122 paths[0] = OS_ROOT_PATH
124 # Trailing "/" is stripped so we need to add back an empty path
125 # for consistency
126 if str(posix).endswith(posixpath.sep):
127 paths.append("")
129 return os.path.join(*paths)
132class NoTransaction:
133 """A simple emulation of the `DatastoreTransaction` class.
135 Does nothing.
136 """
138 def __init__(self) -> None:
139 return
141 @contextlib.contextmanager
142 def undoWith(self, name: str, undoFunc: Callable, *args: Any, **kwargs: Any) -> Iterator[None]:
143 """No-op context manager to replace `DatastoreTransaction`
144 """
145 yield None
148class ButlerURI:
149 """Convenience wrapper around URI parsers.
151 Provides access to URI components and can convert file
152 paths into absolute path URIs. Scheme-less URIs are treated as if
153 they are local file system paths and are converted to absolute URIs.
155 A specialist subclass is created for each supported URI scheme.
157 Parameters
158 ----------
159 uri : `str` or `urllib.parse.ParseResult`
160 URI in string form. Can be scheme-less if referring to a local
161 filesystem path.
162 root : `str` or `ButlerURI`, optional
163 When fixing up a relative path in a ``file`` scheme or if scheme-less,
164 use this as the root. Must be absolute. If `None` the current
165 working directory will be used. Can be a file URI.
166 forceAbsolute : `bool`, optional
167 If `True`, scheme-less relative URI will be converted to an absolute
168 path using a ``file`` scheme. If `False` scheme-less URI will remain
169 scheme-less and will not be updated to ``file`` or absolute path.
170 forceDirectory: `bool`, optional
171 If `True` forces the URI to end with a separator, otherwise given URI
172 is interpreted as is.
173 """
175 _pathLib: Type[PurePath] = PurePosixPath
176 """Path library to use for this scheme."""
178 _pathModule = posixpath
179 """Path module to use for this scheme."""
181 transferModes: Tuple[str, ...] = ("copy", "auto", "move")
182 """Transfer modes supported by this implementation.
184 Move is special in that it is generally a copy followed by an unlink.
185 Whether that unlink works depends critically on whether the source URI
186 implements unlink. If it does not the move will be reported as a failure.
187 """
189 transferDefault: str = "copy"
190 """Default mode to use for transferring if ``auto`` is specified."""
192 quotePaths = True
193 """True if path-like elements modifying a URI should be quoted.
195 All non-schemeless URIs have to internally use quoted paths. Therefore
196 if a new file name is given (e.g. to updateFile or join) a decision must
197 be made whether to quote it to be consistent.
198 """
200 # This is not an ABC with abstract methods because the __new__ being
201 # a factory confuses mypy such that it assumes that every constructor
202 # returns a ButlerURI and then determines that all the abstract methods
203 # are still abstract. If they are not marked abstract but just raise
204 # mypy is fine with it.
206 # mypy is confused without this
207 _uri: urllib.parse.ParseResult
209 def __new__(cls, uri: Union[str, urllib.parse.ParseResult, ButlerURI],
210 root: Optional[Union[str, ButlerURI]] = None, forceAbsolute: bool = True,
211 forceDirectory: bool = False) -> ButlerURI:
212 parsed: urllib.parse.ParseResult
213 dirLike: bool
214 subclass: Optional[Type] = None
216 # Record if we need to post process the URI components
217 # or if the instance is already fully configured
218 if isinstance(uri, str):
219 # Since local file names can have special characters in them
220 # we need to quote them for the parser but we can unquote
221 # later. Assume that all other URI schemes are quoted.
222 # Since sometimes people write file:/a/b and not file:///a/b
223 # we should not quote in the explicit case of file:
224 if "://" not in uri and not uri.startswith("file:"):
225 if ESCAPES_RE.search(uri):
226 log.warning("Possible double encoding of %s", uri)
227 else:
228 uri = urllib.parse.quote(uri)
229 parsed = urllib.parse.urlparse(uri)
230 elif isinstance(uri, urllib.parse.ParseResult):
231 parsed = copy.copy(uri)
232 elif isinstance(uri, ButlerURI):
233 parsed = copy.copy(uri._uri)
234 dirLike = uri.dirLike
235 # No further parsing required and we know the subclass
236 subclass = type(uri)
237 else:
238 raise ValueError(f"Supplied URI must be string, ButlerURI, or ParseResult but got '{uri!r}'")
240 if subclass is None:
241 # Work out the subclass from the URI scheme
242 if not parsed.scheme:
243 subclass = ButlerSchemelessURI
244 elif parsed.scheme == "file":
245 subclass = ButlerFileURI
246 elif parsed.scheme == "s3":
247 subclass = ButlerS3URI
248 elif parsed.scheme.startswith("http"):
249 subclass = ButlerHttpURI
250 elif parsed.scheme == "resource":
251 # Rules for scheme names disasllow pkg_resource
252 subclass = ButlerPackageResourceURI
253 elif parsed.scheme == "mem":
254 # in-memory datastore object
255 subclass = ButlerInMemoryURI
256 else:
257 raise NotImplementedError(f"No URI support for scheme: '{parsed.scheme}'"
258 " in {parsed.geturl()}")
260 parsed, dirLike = subclass._fixupPathUri(parsed, root=root,
261 forceAbsolute=forceAbsolute,
262 forceDirectory=forceDirectory)
264 # It is possible for the class to change from schemeless
265 # to file so handle that
266 if parsed.scheme == "file":
267 subclass = ButlerFileURI
269 # Now create an instance of the correct subclass and set the
270 # attributes directly
271 self = object.__new__(subclass)
272 self._uri = parsed
273 self.dirLike = dirLike
274 return self
276 @property
277 def scheme(self) -> str:
278 """The URI scheme (``://`` is not part of the scheme)."""
279 return self._uri.scheme
281 @property
282 def netloc(self) -> str:
283 """The URI network location."""
284 return self._uri.netloc
286 @property
287 def path(self) -> str:
288 """The path component of the URI."""
289 return self._uri.path
291 @property
292 def unquoted_path(self) -> str:
293 """The path component of the URI with any URI quoting reversed."""
294 return urllib.parse.unquote(self._uri.path)
296 @property
297 def ospath(self) -> str:
298 """Path component of the URI localized to current OS."""
299 raise AttributeError(f"Non-file URI ({self}) has no local OS path.")
301 @property
302 def relativeToPathRoot(self) -> str:
303 """Returns path relative to network location.
305 Effectively, this is the path property with posix separator stripped
306 from the left hand side of the path.
308 Always unquotes.
309 """
310 p = self._pathLib(self.path)
311 relToRoot = str(p.relative_to(p.root))
312 if self.dirLike and not relToRoot.endswith("/"):
313 relToRoot += "/"
314 return urllib.parse.unquote(relToRoot)
316 @property
317 def fragment(self) -> str:
318 """The fragment component of the URI."""
319 return self._uri.fragment
321 @property
322 def params(self) -> str:
323 """Any parameters included in the URI."""
324 return self._uri.params
326 @property
327 def query(self) -> str:
328 """Any query strings included in the URI."""
329 return self._uri.query
331 def geturl(self) -> str:
332 """Return the URI in string form.
334 Returns
335 -------
336 url : `str`
337 String form of URI.
338 """
339 return self._uri.geturl()
341 def split(self) -> Tuple[ButlerURI, str]:
342 """Splits URI into head and tail. Equivalent to os.path.split where
343 head preserves the URI components.
345 Returns
346 -------
347 head: `ButlerURI`
348 Everything leading up to tail, expanded and normalized as per
349 ButlerURI rules.
350 tail : `str`
351 Last `self.path` component. Tail will be empty if path ends on a
352 separator. Tail will never contain separators. It will be
353 unquoted.
354 """
355 head, tail = self._pathModule.split(self.path)
356 headuri = self._uri._replace(path=head)
358 # The file part should never include quoted metacharacters
359 tail = urllib.parse.unquote(tail)
361 # Schemeless is special in that it can be a relative path
362 # We need to ensure that it stays that way. All other URIs will
363 # be absolute already.
364 forceAbsolute = self._pathModule.isabs(self.path)
365 return ButlerURI(headuri, forceDirectory=True, forceAbsolute=forceAbsolute), tail
367 def basename(self) -> str:
368 """Returns the base name, last element of path, of the URI. If URI ends
369 on a slash returns an empty string. This is the second element returned
370 by split().
372 Equivalent of os.path.basename().
374 Returns
375 -------
376 tail : `str`
377 Last part of the path attribute. Trail will be empty if path ends
378 on a separator.
379 """
380 return self.split()[1]
382 def dirname(self) -> ButlerURI:
383 """Returns a ButlerURI containing all the directories of the path
384 attribute.
386 Equivalent of os.path.dirname()
388 Returns
389 -------
390 head : `ButlerURI`
391 Everything except the tail of path attribute, expanded and
392 normalized as per ButlerURI rules.
393 """
394 return self.split()[0]
396 def parent(self) -> ButlerURI:
397 """Returns a ButlerURI containing all the directories of the path
398 attribute, minus the last one.
400 Returns
401 -------
402 head : `ButlerURI`
403 Everything except the tail of path attribute, expanded and
404 normalized as per ButlerURI rules.
405 """
406 # When self is file-like, return self.dirname()
407 if not self.dirLike:
408 return self.dirname()
409 # When self is dir-like, return its parent directory,
410 # regardless of the presence of a trailing separator
411 originalPath = self._pathLib(self.path)
412 parentPath = originalPath.parent
413 parentURI = self._uri._replace(path=str(parentPath))
415 return ButlerURI(parentURI, forceDirectory=True)
417 def replace(self, **kwargs: Any) -> ButlerURI:
418 """Replace components in a URI with new values and return a new
419 instance.
421 Returns
422 -------
423 new : `ButlerURI`
424 New `ButlerURI` object with updated values.
425 """
426 return self.__class__(self._uri._replace(**kwargs))
428 def updateFile(self, newfile: str) -> None:
429 """Update in place the final component of the path with the supplied
430 file name.
432 Parameters
433 ----------
434 newfile : `str`
435 File name with no path component.
437 Notes
438 -----
439 Updates the URI in place.
440 Updates the ButlerURI.dirLike attribute. The new file path will
441 be quoted if necessary.
442 """
443 if self.quotePaths:
444 newfile = urllib.parse.quote(newfile)
445 dir, _ = self._pathModule.split(self.path)
446 newpath = self._pathModule.join(dir, newfile)
448 self.dirLike = False
449 self._uri = self._uri._replace(path=newpath)
451 def getExtension(self) -> str:
452 """Return the file extension(s) associated with this URI path.
454 Returns
455 -------
456 ext : `str`
457 The file extension (including the ``.``). Can be empty string
458 if there is no file extension. Usually returns only the last
459 file extension unless there is a special extension modifier
460 indicating file compression, in which case the combined
461 extension (e.g. ``.fits.gz``) will be returned.
462 """
463 special = {".gz", ".bz2", ".xz", ".fz"}
465 extensions = self._pathLib(self.path).suffixes
467 if not extensions:
468 return ""
470 ext = extensions.pop()
472 # Multiple extensions, decide whether to include the final two
473 if extensions and ext in special:
474 ext = f"{extensions[-1]}{ext}"
476 return ext
478 def join(self, path: str) -> ButlerURI:
479 """Create a new `ButlerURI` with additional path components including
480 a file.
482 Parameters
483 ----------
484 path : `str`
485 Additional file components to append to the current URI. Assumed
486 to include a file at the end. Will be quoted depending on the
487 associated URI scheme.
489 Returns
490 -------
491 new : `ButlerURI`
492 New URI with any file at the end replaced with the new path
493 components.
495 Notes
496 -----
497 Schemeless URIs assume local path separator but all other URIs assume
498 POSIX separator if the supplied path has directory structure. It
499 may be this never becomes a problem but datastore templates assume
500 POSIX separator is being used.
501 """
502 new = self.dirname() # By definition a directory URI
504 # new should be asked about quoting, not self, since dirname can
505 # change the URI scheme for schemeless -> file
506 if new.quotePaths:
507 path = urllib.parse.quote(path)
509 newpath = self._pathModule.normpath(self._pathModule.join(new.path, path))
510 new._uri = new._uri._replace(path=newpath)
511 # Declare the new URI not be dirLike unless path ended in /
512 if not path.endswith(self._pathModule.sep):
513 new.dirLike = False
514 return new
516 def relative_to(self, other: ButlerURI) -> Optional[str]:
517 """Return the relative path from this URI to the other URI.
519 Parameters
520 ----------
521 other : `ButlerURI`
522 URI to use to calculate the relative path. Must be a parent
523 of this URI.
525 Returns
526 -------
527 subpath : `str`
528 The sub path of this URI relative to the supplied other URI.
529 Returns `None` if there is no parent child relationship.
530 Scheme and netloc must match.
531 """
532 if self.scheme != other.scheme or self.netloc != other.netloc:
533 return None
535 enclosed_path = self._pathLib(self.relativeToPathRoot)
536 parent_path = other.relativeToPathRoot
537 subpath: Optional[str]
538 try:
539 subpath = str(enclosed_path.relative_to(parent_path))
540 except ValueError:
541 subpath = None
542 else:
543 subpath = urllib.parse.unquote(subpath)
544 return subpath
546 def exists(self) -> bool:
547 """Indicate that the resource is available.
549 Returns
550 -------
551 exists : `bool`
552 `True` if the resource exists.
553 """
554 raise NotImplementedError()
556 def remove(self) -> None:
557 """Remove the resource."""
558 raise NotImplementedError()
560 def isabs(self) -> bool:
561 """Indicate that the resource is fully specified.
563 For non-schemeless URIs this is always true.
565 Returns
566 -------
567 isabs : `bool`
568 `True` in all cases except schemeless URI.
569 """
570 return True
572 def as_local(self) -> Tuple[str, bool]:
573 """Return the location of the (possibly remote) resource in the
574 local file system.
576 Returns
577 -------
578 path : `str`
579 If this is a remote resource, it will be a copy of the resource
580 on the local file system, probably in a temporary directory.
581 For a local resource this should be the actual path to the
582 resource.
583 is_temporary : `bool`
584 Indicates if the local path is a temporary file or not.
585 """
586 raise NotImplementedError()
588 def read(self, size: int = -1) -> bytes:
589 """Open the resource and return the contents in bytes.
591 Parameters
592 ----------
593 size : `int`, optional
594 The number of bytes to read. Negative or omitted indicates
595 that all data should be read.
596 """
597 raise NotImplementedError()
599 def write(self, data: bytes, overwrite: bool = True) -> None:
600 """Write the supplied bytes to the new resource.
602 Parameters
603 ----------
604 data : `bytes`
605 The bytes to write to the resource. The entire contents of the
606 resource will be replaced.
607 overwrite : `bool`, optional
608 If `True` the resource will be overwritten if it exists. Otherwise
609 the write will fail.
610 """
611 raise NotImplementedError()
613 def mkdir(self) -> None:
614 """For a dir-like URI, create the directory resource if it does not
615 already exist.
616 """
617 raise NotImplementedError()
619 def size(self) -> int:
620 """For non-dir-like URI, return the size of the resource.
622 Returns
623 -------
624 sz : `int`
625 The size in bytes of the resource associated with this URI.
626 Returns 0 if dir-like.
627 """
628 raise NotImplementedError()
630 def __str__(self) -> str:
631 return self.geturl()
633 def __repr__(self) -> str:
634 return f'ButlerURI("{self.geturl()}")'
636 def __eq__(self, other: Any) -> bool:
637 if not isinstance(other, ButlerURI):
638 return False
639 return self.geturl() == other.geturl()
641 def __copy__(self) -> ButlerURI:
642 # Implement here because the __new__ method confuses things
643 return type(self)(str(self))
645 def __deepcopy__(self, memo: Any) -> ButlerURI:
646 # Implement here because the __new__ method confuses things
647 return self.__copy__()
649 def __getnewargs__(self) -> Tuple:
650 return (str(self),)
652 @staticmethod
653 def _fixupPathUri(parsed: urllib.parse.ParseResult, root: Optional[Union[str, ButlerURI]] = None,
654 forceAbsolute: bool = False,
655 forceDirectory: bool = False) -> Tuple[urllib.parse.ParseResult, bool]:
656 """Correct any issues with the supplied URI.
658 Parameters
659 ----------
660 parsed : `~urllib.parse.ParseResult`
661 The result from parsing a URI using `urllib.parse`.
662 root : `str` or `ButlerURI`, ignored
663 Not used by the this implementation since all URIs are
664 absolute except for those representing the local file system.
665 forceAbsolute : `bool`, ignored.
666 Not used by this implementation. URIs are generally always
667 absolute.
668 forceDirectory : `bool`, optional
669 If `True` forces the URI to end with a separator, otherwise given
670 URI is interpreted as is. Specifying that the URI is conceptually
671 equivalent to a directory can break some ambiguities when
672 interpreting the last element of a path.
674 Returns
675 -------
676 modified : `~urllib.parse.ParseResult`
677 Update result if a URI is being handled.
678 dirLike : `bool`
679 `True` if given parsed URI has a trailing separator or
680 forceDirectory is True. Otherwise `False`.
682 Notes
683 -----
684 Relative paths are explicitly not supported by RFC8089 but `urllib`
685 does accept URIs of the form ``file:relative/path.ext``. They need
686 to be turned into absolute paths before they can be used. This is
687 always done regardless of the ``forceAbsolute`` parameter.
689 AWS S3 differentiates between keys with trailing POSIX separators (i.e
690 `/dir` and `/dir/`) whereas POSIX does not neccessarily.
692 Scheme-less paths are normalized.
693 """
694 # assume we are not dealing with a directory like URI
695 dirLike = False
697 # URI is dir-like if explicitly stated or if it ends on a separator
698 endsOnSep = parsed.path.endswith(posixpath.sep)
699 if forceDirectory or endsOnSep:
700 dirLike = True
701 # only add the separator if it's not already there
702 if not endsOnSep:
703 parsed = parsed._replace(path=parsed.path+posixpath.sep)
705 return parsed, dirLike
707 def transfer_from(self, src: ButlerURI, transfer: str,
708 overwrite: bool = False,
709 transaction: Optional[Union[DatastoreTransaction, NoTransaction]] = None) -> None:
710 """Transfer the current resource to a new location.
712 Parameters
713 ----------
714 src : `ButlerURI`
715 Source URI.
716 transfer : `str`
717 Mode to use for transferring the resource. Generically there are
718 many standard options: copy, link, symlink, hardlink, relsymlink.
719 Not all URIs support all modes.
720 overwrite : `bool`, optional
721 Allow an existing file to be overwritten. Defaults to `False`.
722 transaction : `DatastoreTransaction`, optional
723 A transaction object that can (depending on implementation)
724 rollback transfers on error. Not guaranteed to be implemented.
726 Notes
727 -----
728 Conceptually this is hard to scale as the number of URI schemes
729 grow. The destination URI is more important than the source URI
730 since that is where all the transfer modes are relevant (with the
731 complication that "move" deletes the source).
733 Local file to local file is the fundamental use case but every
734 other scheme has to support "copy" to local file (with implicit
735 support for "move") and copy from local file.
736 All the "link" options tend to be specific to local file systems.
738 "move" is a "copy" where the remote resource is deleted at the end.
739 Whether this works depends on the source URI rather than the
740 destination URI. Reverting a move on transaction rollback is
741 expected to be problematic if a remote resource was involved.
742 """
743 raise NotImplementedError(f"No transfer modes supported by URI scheme {self.scheme}")
746class ButlerFileURI(ButlerURI):
747 """URI for explicit ``file`` scheme."""
749 transferModes = ("copy", "link", "symlink", "hardlink", "relsymlink", "auto", "move")
750 transferDefault: str = "link"
752 @property
753 def ospath(self) -> str:
754 """Path component of the URI localized to current OS.
756 Will unquote URI path since a formal URI must include the quoting.
757 """
758 return urllib.parse.unquote(posix2os(self._uri.path))
760 def exists(self) -> bool:
761 # Uses os.path.exists so if there is a soft link that points
762 # to a file that no longer exists this will return False
763 return os.path.exists(self.ospath)
765 def size(self) -> int:
766 if not os.path.isdir(self.ospath):
767 stat = os.stat(self.ospath)
768 sz = stat.st_size
769 else:
770 sz = 0
771 return sz
773 def remove(self) -> None:
774 """Remove the resource."""
775 os.remove(self.ospath)
777 def as_local(self) -> Tuple[str, bool]:
778 """Return the local path of the file.
780 Returns
781 -------
782 path : `str`
783 The local path to this file.
784 temporary : `bool`
785 Always returns `False` (this is not a temporary file).
786 """
787 return self.ospath, False
789 def _force_to_file(self) -> ButlerFileURI:
790 """Force a schemeless URI to a file URI and returns a new URI.
792 Returns
793 -------
794 file : `ButlerFileURI`
795 A copy of the URI using file scheme. If already a file scheme
796 the copy will be identical.
798 Raises
799 ------
800 ValueError
801 Raised if this URI is schemeless and relative path and so can
802 not be forced to file absolute path without context.
803 """
804 # This is always a file scheme so always return copy
805 return copy.copy(self)
807 def relative_to(self, other: ButlerURI) -> Optional[str]:
808 """Return the relative path from this URI to the other URI.
810 Parameters
811 ----------
812 other : `ButlerURI`
813 URI to use to calculate the relative path. Must be a parent
814 of this URI.
816 Returns
817 -------
818 subpath : `str`
819 The sub path of this URI relative to the supplied other URI.
820 Returns `None` if there is no parent child relationship.
821 Scheme and netloc must match but for file URIs schemeless
822 is also used. If this URI is a relative URI but the other is
823 absolute, it is assumed to be in the parent completely unless it
824 starts with ".." (in which case the path is combined and tested).
825 If both URIs are relative, the relative paths are compared
826 for commonality.
828 Notes
829 -----
830 By definition a relative path will be relative to the enclosing
831 absolute parent URI. It will be returned unchanged if it does not
832 use a parent directory specification.
833 """
834 # We know self is a file so check the other. Anything other than
835 # file or schemeless means by definition these have no paths in common
836 if other.scheme and other.scheme != "file":
837 return None
839 # for case where both URIs are relative use the normal logic
840 # where a/b/c.txt and a/b/ returns c.txt.
841 if not self.isabs() and not other.isabs():
842 return super().relative_to(other)
844 # if we have a relative path convert it to absolute
845 # relative to the supplied parent. This is solely to handle
846 # the case where the relative path includes ".." but somehow
847 # then goes back inside the directory of the parent
848 if not self.isabs():
849 childUri = other.join(self.path)
850 return childUri.relative_to(other)
852 # By this point if the schemes are identical we can use the
853 # base class implementation.
854 if self.scheme == other.scheme:
855 return super().relative_to(other)
857 # if one is schemeless and the other is not the base implementation
858 # will fail so we need to fix that -- they are both absolute so
859 # forcing to file is fine.
860 # Use a cast to convince mypy that other has to be a ButlerFileURI
861 # in order to get to this part of the code.
862 return self._force_to_file().relative_to(cast(ButlerFileURI, other)._force_to_file())
864 def read(self, size: int = -1) -> bytes:
865 # Docstring inherits
866 with open(self.ospath, "rb") as fh:
867 return fh.read(size)
869 def write(self, data: bytes, overwrite: bool = True) -> None:
870 dir = os.path.dirname(self.ospath)
871 if not os.path.exists(dir):
872 safeMakeDir(dir)
873 if overwrite:
874 mode = "wb"
875 else:
876 mode = "xb"
877 with open(self.ospath, mode) as f:
878 f.write(data)
880 def mkdir(self) -> None:
881 if not os.path.exists(self.ospath):
882 safeMakeDir(self.ospath)
883 elif not os.path.isdir(self.ospath):
884 raise FileExistsError(f"URI {self} exists but is not a directory!")
886 def transfer_from(self, src: ButlerURI, transfer: str,
887 overwrite: bool = False,
888 transaction: Optional[Union[DatastoreTransaction, NoTransaction]] = None) -> None:
889 """Transfer the current resource to a local file.
891 Parameters
892 ----------
893 src : `ButlerURI`
894 Source URI.
895 transfer : `str`
896 Mode to use for transferring the resource. Supports the following
897 options: copy, link, symlink, hardlink, relsymlink.
898 overwrite : `bool`, optional
899 Allow an existing file to be overwritten. Defaults to `False`.
900 transaction : `DatastoreTransaction`, optional
901 If a transaction is provided, undo actions will be registered.
902 """
903 # Fail early to prevent delays if remote resources are requested
904 if transfer not in self.transferModes:
905 raise ValueError(f"Transfer mode '{transfer}' not supported by URI scheme {self.scheme}")
907 log.debug(f"Transferring {src} [exists: {src.exists()}] -> "
908 f"{self} [exists: {self.exists()}] (transfer={transfer})")
910 # We do not have to special case ButlerFileURI here because
911 # as_local handles that.
912 local_src, is_temporary = src.as_local()
914 # Default transfer mode depends on whether we have a temporary
915 # file or not.
916 if transfer == "auto":
917 transfer = self.transferDefault if not is_temporary else "copy"
919 # Follow soft links
920 local_src = os.path.realpath(os.path.normpath(local_src))
922 if not os.path.exists(local_src):
923 raise FileNotFoundError(f"Source URI {src} does not exist")
925 # All the modes involving linking use "link" somewhere
926 if "link" in transfer and is_temporary:
927 raise RuntimeError("Can not use local file system transfer mode"
928 f" {transfer} for remote resource ({src})")
930 # For temporary files we can own them
931 requested_transfer = transfer
932 if is_temporary and transfer == "copy":
933 transfer = "move"
935 # The output location should not exist
936 dest_exists = self.exists()
937 if not overwrite and dest_exists:
938 raise FileExistsError(f"Destination path '{self}' already exists. Transfer "
939 f"from {src} cannot be completed.")
941 # Make the path absolute (but don't follow links since that
942 # would possibly cause us to end up in the wrong place if the
943 # file existed already as a soft link)
944 newFullPath = os.path.abspath(self.ospath)
945 outputDir = os.path.dirname(newFullPath)
946 if not os.path.isdir(outputDir):
947 # Must create the directory -- this can not be rolled back
948 # since another transfer running concurrently may
949 # be relying on this existing.
950 safeMakeDir(outputDir)
952 if transaction is None:
953 # Use a no-op transaction to reduce code duplication
954 transaction = NoTransaction()
956 # For links the OS doesn't let us overwrite so if something does
957 # exist we have to remove it before we do the actual "transfer" below
958 if "link" in transfer and overwrite and dest_exists:
959 try:
960 self.remove()
961 except Exception:
962 # If this fails we ignore it since it's a problem
963 # that will manifest immediately below with a more relevant
964 # error message
965 pass
967 if transfer == "move":
968 with transaction.undoWith(f"move from {local_src}", shutil.move, newFullPath, local_src):
969 shutil.move(local_src, newFullPath)
970 elif transfer == "copy":
971 with transaction.undoWith(f"copy from {local_src}", os.remove, newFullPath):
972 shutil.copy(local_src, newFullPath)
973 elif transfer == "link":
974 # Try hard link and if that fails use a symlink
975 with transaction.undoWith(f"link to {local_src}", os.remove, newFullPath):
976 try:
977 os.link(local_src, newFullPath)
978 except OSError:
979 # Read through existing symlinks
980 os.symlink(local_src, newFullPath)
981 elif transfer == "hardlink":
982 with transaction.undoWith(f"hardlink to {local_src}", os.remove, newFullPath):
983 os.link(local_src, newFullPath)
984 elif transfer == "symlink":
985 # Read through existing symlinks
986 with transaction.undoWith(f"symlink to {local_src}", os.remove, newFullPath):
987 os.symlink(local_src, newFullPath)
988 elif transfer == "relsymlink":
989 # This is a standard symlink but using a relative path
990 # Need the directory name to give to relative root
991 # A full file path confuses it into an extra ../
992 newFullPathRoot = os.path.dirname(newFullPath)
993 relPath = os.path.relpath(local_src, newFullPathRoot)
994 with transaction.undoWith(f"relsymlink to {local_src}", os.remove, newFullPath):
995 os.symlink(relPath, newFullPath)
996 else:
997 raise NotImplementedError("Transfer type '{}' not supported.".format(transfer))
999 # This was an explicit move requested from a remote resource
1000 # try to remove that resource. We check is_temporary because
1001 # the local file would have been moved by shutil.move already.
1002 if requested_transfer == "move" and is_temporary:
1003 # Transactions do not work here
1004 src.remove()
1006 if is_temporary and os.path.exists(local_src):
1007 # This should never happen since we have moved it above
1008 os.remove(local_src)
1010 @staticmethod
1011 def _fixupPathUri(parsed: urllib.parse.ParseResult, root: Optional[Union[str, ButlerURI]] = None,
1012 forceAbsolute: bool = False,
1013 forceDirectory: bool = False) -> Tuple[urllib.parse.ParseResult, bool]:
1014 """Fix up relative paths in URI instances.
1016 Parameters
1017 ----------
1018 parsed : `~urllib.parse.ParseResult`
1019 The result from parsing a URI using `urllib.parse`.
1020 root : `str` or `ButlerURI`, optional
1021 Path to use as root when converting relative to absolute.
1022 If `None`, it will be the current working directory. This
1023 is a local file system path, or a file URI. It is only used if
1024 a file-scheme is used incorrectly with a relative path.
1025 forceAbsolute : `bool`, ignored
1026 Has no effect for this subclass. ``file`` URIs are always
1027 absolute.
1028 forceDirectory : `bool`, optional
1029 If `True` forces the URI to end with a separator, otherwise given
1030 URI is interpreted as is.
1032 Returns
1033 -------
1034 modified : `~urllib.parse.ParseResult`
1035 Update result if a URI is being handled.
1036 dirLike : `bool`
1037 `True` if given parsed URI has a trailing separator or
1038 forceDirectory is True. Otherwise `False`.
1040 Notes
1041 -----
1042 Relative paths are explicitly not supported by RFC8089 but `urllib`
1043 does accept URIs of the form ``file:relative/path.ext``. They need
1044 to be turned into absolute paths before they can be used. This is
1045 always done regardless of the ``forceAbsolute`` parameter.
1046 """
1047 # assume we are not dealing with a directory like URI
1048 dirLike = False
1050 # file URI implies POSIX path separators so split as POSIX,
1051 # then join as os, and convert to abspath. Do not handle
1052 # home directories since "file" scheme is explicitly documented
1053 # to not do tilde expansion.
1054 sep = posixpath.sep
1056 # For local file system we can explicitly check to see if this
1057 # really is a directory. The URI might point to a location that
1058 # does not exists yet but all that matters is if it is a directory
1059 # then we make sure use that fact. No need to do the check if
1060 # we are already being told.
1061 if not forceDirectory and posixpath.isdir(parsed.path):
1062 forceDirectory = True
1064 # For an absolute path all we need to do is check if we need
1065 # to force the directory separator
1066 if posixpath.isabs(parsed.path):
1067 if forceDirectory:
1068 if not parsed.path.endswith(sep):
1069 parsed = parsed._replace(path=parsed.path+sep)
1070 dirLike = True
1071 return copy.copy(parsed), dirLike
1073 # Relative path so must fix it to be compliant with the standard
1075 # Replacement values for the URI
1076 replacements = {}
1078 if root is None:
1079 root = os.path.abspath(os.path.curdir)
1080 elif isinstance(root, ButlerURI):
1081 if root.scheme and root.scheme != "file":
1082 raise RuntimeError(f"The override root must be a file URI not {root.scheme}")
1083 root = os.path.abspath(root.ospath)
1085 replacements["path"] = posixpath.normpath(posixpath.join(os2posix(root), parsed.path))
1087 # normpath strips trailing "/" so put it back if necessary
1088 # Acknowledge that trailing separator exists.
1089 if forceDirectory or (parsed.path.endswith(sep) and not replacements["path"].endswith(sep)):
1090 replacements["path"] += sep
1091 dirLike = True
1093 # ParseResult is a NamedTuple so _replace is standard API
1094 parsed = parsed._replace(**replacements)
1096 if parsed.params or parsed.query:
1097 log.warning("Additional items unexpectedly encountered in file URI: %s", parsed.geturl())
1099 return parsed, dirLike
1102class ButlerS3URI(ButlerURI):
1103 """S3 URI"""
1105 @property
1106 def client(self) -> boto3.client:
1107 """Client object to address remote resource."""
1108 # Defer import for circular dependencies
1109 from .s3utils import getS3Client
1110 return getS3Client()
1112 def exists(self) -> bool:
1113 # s3utils itself imports ButlerURI so defer this import
1114 from .s3utils import s3CheckFileExists
1115 exists, _ = s3CheckFileExists(self, client=self.client)
1116 return exists
1118 def size(self) -> int:
1119 # s3utils itself imports ButlerURI so defer this import
1120 from .s3utils import s3CheckFileExists
1121 if self.dirLike:
1122 return 0
1123 _, sz = s3CheckFileExists(self, client=self.client)
1124 return sz
1126 def remove(self) -> None:
1127 """Remove the resource."""
1129 # https://github.com/boto/boto3/issues/507 - there is no
1130 # way of knowing if the file was actually deleted except
1131 # for checking all the keys again, reponse is HTTP 204 OK
1132 # response all the time
1133 self.client.delete_object(Bucket=self.netloc, Key=self.relativeToPathRoot)
1135 def read(self, size: int = -1) -> bytes:
1136 args = {}
1137 if size > 0:
1138 args["Range"] = f"bytes=0-{size-1}"
1139 try:
1140 response = self.client.get_object(Bucket=self.netloc,
1141 Key=self.relativeToPathRoot,
1142 **args)
1143 except (self.client.exceptions.NoSuchKey, self.client.exceptions.NoSuchBucket) as err:
1144 raise FileNotFoundError(f"No such resource: {self}") from err
1145 body = response["Body"].read()
1146 response["Body"].close()
1147 return body
1149 def write(self, data: bytes, overwrite: bool = True) -> None:
1150 if not overwrite:
1151 if self.exists():
1152 raise FileExistsError(f"Remote resource {self} exists and overwrite has been disabled")
1153 self.client.put_object(Bucket=self.netloc, Key=self.relativeToPathRoot,
1154 Body=data)
1156 def mkdir(self) -> None:
1157 # Defer import for circular dependencies
1158 from .s3utils import bucketExists
1159 if not bucketExists(self.netloc):
1160 raise ValueError(f"Bucket {self.netloc} does not exist for {self}!")
1162 if not self.dirLike:
1163 raise ValueError(f"Can not create a 'directory' for file-like URI {self}")
1165 # don't create S3 key when root is at the top-level of an Bucket
1166 if not self.path == "/":
1167 self.client.put_object(Bucket=self.netloc, Key=self.relativeToPathRoot)
1169 def as_local(self) -> Tuple[str, bool]:
1170 """Download object from S3 and place in temporary directory.
1172 Returns
1173 -------
1174 path : `str`
1175 Path to local temporary file.
1176 temporary : `bool`
1177 Always returns `True`. This is always a temporary file.
1178 """
1179 with tempfile.NamedTemporaryFile(suffix=self.getExtension(), delete=False) as tmpFile:
1180 self.client.download_fileobj(self.netloc, self.relativeToPathRoot, tmpFile)
1181 return tmpFile.name, True
1183 def transfer_from(self, src: ButlerURI, transfer: str = "copy",
1184 overwrite: bool = False,
1185 transaction: Optional[Union[DatastoreTransaction, NoTransaction]] = None) -> None:
1186 """Transfer the current resource to an S3 bucket.
1188 Parameters
1189 ----------
1190 src : `ButlerURI`
1191 Source URI.
1192 transfer : `str`
1193 Mode to use for transferring the resource. Supports the following
1194 options: copy.
1195 overwrite : `bool`, optional
1196 Allow an existing file to be overwritten. Defaults to `False`.
1197 transaction : `DatastoreTransaction`, optional
1198 Currently unused.
1199 """
1200 # Fail early to prevent delays if remote resources are requested
1201 if transfer not in self.transferModes:
1202 raise ValueError(f"Transfer mode '{transfer}' not supported by URI scheme {self.scheme}")
1204 log.debug(f"Transferring {src} [exists: {src.exists()}] -> "
1205 f"{self} [exists: {self.exists()}] (transfer={transfer})")
1207 if not overwrite and self.exists():
1208 raise FileExistsError(f"Destination path '{self}' already exists.")
1210 if transfer == "auto":
1211 transfer = self.transferDefault
1213 if isinstance(src, type(self)):
1214 # Looks like an S3 remote uri so we can use direct copy
1215 # note that boto3.resource.meta.copy is cleverer than the low
1216 # level copy_object
1217 copy_source = {
1218 "Bucket": src.netloc,
1219 "Key": src.relativeToPathRoot,
1220 }
1221 self.client.copy_object(CopySource=copy_source, Bucket=self.netloc, Key=self.relativeToPathRoot)
1222 else:
1223 # Use local file and upload it
1224 local_src, is_temporary = src.as_local()
1226 # resource.meta.upload_file seems like the right thing
1227 # but we have a low level client
1228 with open(local_src, "rb") as fh:
1229 self.client.put_object(Bucket=self.netloc,
1230 Key=self.relativeToPathRoot, Body=fh)
1231 if is_temporary:
1232 os.remove(local_src)
1234 # This was an explicit move requested from a remote resource
1235 # try to remove that resource
1236 if transfer == "move":
1237 # Transactions do not work here
1238 src.remove()
1241class ButlerPackageResourceURI(ButlerURI):
1242 """URI referring to a Python package resource.
1244 These URIs look like: ``resource://lsst.daf.butler/configs/file.yaml``
1245 where the network location is the Python package and the path is the
1246 resource name.
1247 """
1249 def exists(self) -> bool:
1250 """Check that the python resource exists."""
1251 return pkg_resources.resource_exists(self.netloc, self.relativeToPathRoot)
1253 def read(self, size: int = -1) -> bytes:
1254 with pkg_resources.resource_stream(self.netloc, self.relativeToPathRoot) as fh:
1255 return fh.read(size)
1258class ButlerHttpURI(ButlerURI):
1259 """General HTTP(S) resource."""
1261 @property
1262 def session(self) -> requests.Session:
1263 """Client object to address remote resource."""
1264 from .webdavutils import getHttpSession, isWebdavEndpoint
1265 baseURL = self.scheme + "://" + self.netloc
1266 if isWebdavEndpoint(baseURL):
1267 log.debug("%s looks like a Webdav endpoint.", baseURL)
1268 return getHttpSession()
1270 log.debug("%s looks like a standard HTTP endpoint.", baseURL)
1271 return requests.Session()
1273 def exists(self) -> bool:
1274 """Check that a remote HTTP resource exists."""
1275 log.debug("Checking if resource exists: %s", self.geturl())
1276 r = self.session.head(self.geturl())
1278 return True if r.status_code == 200 else False
1280 def size(self) -> int:
1281 if self.dirLike:
1282 return 0
1283 r = self.session.head(self.geturl())
1284 if r.status_code == 200:
1285 return int(r.headers['Content-Length'])
1286 else:
1287 raise FileNotFoundError(f"Resource {self} does not exist")
1289 def mkdir(self) -> None:
1290 """For a dir-like URI, create the directory resource if it does not
1291 already exist.
1292 """
1293 if not self.dirLike:
1294 raise ValueError(f"Can not create a 'directory' for file-like URI {self}")
1296 if not self.exists():
1297 # We need to test the absence of the parent directory,
1298 # but also if parent URL is different from self URL,
1299 # otherwise we could be stuck in a recursive loop
1300 # where self == parent
1301 if not self.parent().exists() and self.parent().geturl() != self.geturl():
1302 self.parent().mkdir()
1303 log.debug("Creating new directory: %s", self.geturl())
1304 r = self.session.request("MKCOL", self.geturl())
1305 if r.status_code != 201:
1306 raise ValueError(f"Can not create directory {self}, status code: {r.status_code}")
1308 def remove(self) -> None:
1309 """Remove the resource."""
1310 log.debug("Removing resource: %s", self.geturl())
1311 r = self.session.delete(self.geturl())
1312 if r.status_code not in [200, 202, 204]:
1313 raise FileNotFoundError(f"Unable to delete resource {self}; status code: {r.status_code}")
1315 def as_local(self) -> Tuple[str, bool]:
1316 """Download object over HTTP and place in temporary directory.
1318 Returns
1319 -------
1320 path : `str`
1321 Path to local temporary file.
1322 temporary : `bool`
1323 Always returns `True`. This is always a temporary file.
1324 """
1325 log.debug("Downloading remote resource as local file: %s", self.geturl())
1326 r = self.session.get(self.geturl(), stream=True)
1327 if r.status_code != 200:
1328 raise FileNotFoundError(f"Unable to download resource {self}; status code: {r.status_code}")
1329 with tempfile.NamedTemporaryFile(suffix=self.getExtension(), delete=False) as tmpFile:
1330 for chunk in r.iter_content():
1331 tmpFile.write(chunk)
1332 return tmpFile.name, True
1334 def read(self, size: int = -1) -> bytes:
1335 """Open the resource and return the contents in bytes.
1337 Parameters
1338 ----------
1339 size : `int`, optional
1340 The number of bytes to read. Negative or omitted indicates
1341 that all data should be read.
1342 """
1343 log.debug("Reading from remote resource: %s", self.geturl())
1344 stream = True if size > 0 else False
1345 r = self.session.get(self.geturl(), stream=stream)
1346 if r.status_code != 200:
1347 raise FileNotFoundError(f"Unable to read resource {self}; status code: {r.status_code}")
1348 if not stream:
1349 return r.content
1350 else:
1351 return next(r.iter_content(chunk_size=size))
1353 def write(self, data: bytes, overwrite: bool = True) -> None:
1354 """Write the supplied bytes to the new resource.
1356 Parameters
1357 ----------
1358 data : `bytes`
1359 The bytes to write to the resource. The entire contents of the
1360 resource will be replaced.
1361 overwrite : `bool`, optional
1362 If `True` the resource will be overwritten if it exists. Otherwise
1363 the write will fail.
1364 """
1365 log.debug("Writing to remote resource: %s", self.geturl())
1366 if not overwrite:
1367 if self.exists():
1368 raise FileExistsError(f"Remote resource {self} exists and overwrite has been disabled")
1369 self.session.put(self.geturl(), data=data)
1371 def transfer_from(self, src: ButlerURI, transfer: str = "copy",
1372 overwrite: bool = False,
1373 transaction: Optional[Union[DatastoreTransaction, NoTransaction]] = None) -> None:
1374 """Transfer the current resource to a Webdav repository.
1376 Parameters
1377 ----------
1378 src : `ButlerURI`
1379 Source URI.
1380 transfer : `str`
1381 Mode to use for transferring the resource. Supports the following
1382 options: copy.
1383 transaction : `DatastoreTransaction`, optional
1384 Currently unused.
1385 """
1386 # Fail early to prevent delays if remote resources are requested
1387 if transfer not in self.transferModes:
1388 raise ValueError(f"Transfer mode {transfer} not supported by URI scheme {self.scheme}")
1390 log.debug(f"Transferring {src} [exists: {src.exists()}] -> "
1391 f"{self} [exists: {self.exists()}] (transfer={transfer})")
1393 if self.exists():
1394 raise FileExistsError(f"Destination path {self} already exists.")
1396 if transfer == "auto":
1397 transfer = self.transferDefault
1399 if isinstance(src, type(self)):
1400 if transfer == "move":
1401 self.session.request("MOVE", src.geturl(), headers={"Destination": self.geturl()})
1402 log.debug("Direct move via MOVE operation executed.")
1403 else:
1404 self.session.request("COPY", src.geturl(), headers={"Destination": self.geturl()})
1405 log.debug("Direct copy via COPY operation executed.")
1406 else:
1407 # Use local file and upload it
1408 local_src, is_temporary = src.as_local()
1409 f = open(local_src, "rb")
1410 self.session.put(self.geturl(), data=f)
1411 f.close()
1412 if is_temporary:
1413 os.remove(local_src)
1414 log.debug("Indirect copy via temporary file executed.")
1417class ButlerInMemoryURI(ButlerURI):
1418 """Internal in-memory datastore URI (`mem://`).
1420 Not used for any real purpose other than indicating that the dataset
1421 is in memory.
1422 """
1424 def exists(self) -> bool:
1425 """Test for existence and always return False."""
1426 return True
1428 def as_local(self) -> Tuple[str, bool]:
1429 raise RuntimeError(f"Do not know how to retrieve data for URI '{self}'")
1432class ButlerSchemelessURI(ButlerFileURI):
1433 """Scheme-less URI referring to the local file system"""
1435 _pathLib = PurePath
1436 _pathModule = os.path
1437 quotePaths = False
1439 @property
1440 def ospath(self) -> str:
1441 """Path component of the URI localized to current OS."""
1442 return self.path
1444 def isabs(self) -> bool:
1445 """Indicate that the resource is fully specified.
1447 For non-schemeless URIs this is always true.
1449 Returns
1450 -------
1451 isabs : `bool`
1452 `True` if the file is absolute, `False` otherwise.
1453 """
1454 return os.path.isabs(self.ospath)
1456 def _force_to_file(self) -> ButlerFileURI:
1457 """Force a schemeless URI to a file URI and returns a new URI.
1459 This will include URI quoting of the path.
1461 Returns
1462 -------
1463 file : `ButlerFileURI`
1464 A copy of the URI using file scheme. If already a file scheme
1465 the copy will be identical.
1467 Raises
1468 ------
1469 ValueError
1470 Raised if this URI is schemeless and relative path and so can
1471 not be forced to file absolute path without context.
1472 """
1473 if not self.isabs():
1474 raise RuntimeError(f"Internal error: Can not force {self} to absolute file URI")
1475 uri = self._uri._replace(scheme="file", path=urllib.parse.quote(os2posix(self.path)))
1476 # mypy really wants a ButlerFileURI to be returned here
1477 return ButlerURI(uri, forceDirectory=self.dirLike) # type: ignore
1479 @staticmethod
1480 def _fixupPathUri(parsed: urllib.parse.ParseResult, root: Optional[Union[str, ButlerURI]] = None,
1481 forceAbsolute: bool = False,
1482 forceDirectory: bool = False) -> Tuple[urllib.parse.ParseResult, bool]:
1483 """Fix up relative paths for local file system.
1485 Parameters
1486 ----------
1487 parsed : `~urllib.parse.ParseResult`
1488 The result from parsing a URI using `urllib.parse`.
1489 root : `str` or `ButlerURI`, optional
1490 Path to use as root when converting relative to absolute.
1491 If `None`, it will be the current working directory. This
1492 is a local file system path, or a file URI.
1493 forceAbsolute : `bool`, optional
1494 If `True`, scheme-less relative URI will be converted to an
1495 absolute path using a ``file`` scheme. If `False` scheme-less URI
1496 will remain scheme-less and will not be updated to ``file`` or
1497 absolute path.
1498 forceDirectory : `bool`, optional
1499 If `True` forces the URI to end with a separator, otherwise given
1500 URI is interpreted as is.
1502 Returns
1503 -------
1504 modified : `~urllib.parse.ParseResult`
1505 Update result if a URI is being handled.
1506 dirLike : `bool`
1507 `True` if given parsed URI has a trailing separator or
1508 forceDirectory is True. Otherwise `False`.
1510 Notes
1511 -----
1512 Relative paths are explicitly not supported by RFC8089 but `urllib`
1513 does accept URIs of the form ``file:relative/path.ext``. They need
1514 to be turned into absolute paths before they can be used. This is
1515 always done regardless of the ``forceAbsolute`` parameter.
1517 Scheme-less paths are normalized.
1518 """
1519 # assume we are not dealing with a directory URI
1520 dirLike = False
1522 # Replacement values for the URI
1523 replacements = {}
1525 if root is None:
1526 root = os.path.abspath(os.path.curdir)
1527 elif isinstance(root, ButlerURI):
1528 if root.scheme and root.scheme != "file":
1529 raise RuntimeError(f"The override root must be a file URI not {root.scheme}")
1530 root = os.path.abspath(root.ospath)
1532 # this is a local OS file path which can support tilde expansion.
1533 # we quoted it in the constructor so unquote here
1534 expandedPath = os.path.expanduser(urllib.parse.unquote(parsed.path))
1536 # Ensure that this becomes a file URI if it is already absolute
1537 if os.path.isabs(expandedPath):
1538 replacements["scheme"] = "file"
1539 # Keep in OS form for now to simplify later logic
1540 replacements["path"] = os.path.normpath(expandedPath)
1541 elif forceAbsolute:
1542 # This can stay in OS path form, do not change to file
1543 # scheme.
1544 replacements["path"] = os.path.normpath(os.path.join(root, expandedPath))
1545 else:
1546 # No change needed for relative local path staying relative
1547 # except normalization
1548 replacements["path"] = os.path.normpath(expandedPath)
1549 # normalization of empty path returns "." so we are dirLike
1550 if expandedPath == "":
1551 dirLike = True
1553 # normpath strips trailing "/" which makes it hard to keep
1554 # track of directory vs file when calling replaceFile
1556 # For local file system we can explicitly check to see if this
1557 # really is a directory. The URI might point to a location that
1558 # does not exists yet but all that matters is if it is a directory
1559 # then we make sure use that fact. No need to do the check if
1560 # we are already being told.
1561 if not forceDirectory and os.path.isdir(replacements["path"]):
1562 forceDirectory = True
1564 # add the trailing separator only if explicitly required or
1565 # if it was stripped by normpath. Acknowledge that trailing
1566 # separator exists.
1567 endsOnSep = expandedPath.endswith(os.sep) and not replacements["path"].endswith(os.sep)
1568 if (forceDirectory or endsOnSep or dirLike):
1569 dirLike = True
1570 if not replacements["path"].endswith(os.sep):
1571 replacements["path"] += os.sep
1573 if "scheme" in replacements:
1574 # This is now meant to be a URI path so force to posix
1575 # and quote
1576 replacements["path"] = urllib.parse.quote(os2posix(replacements["path"]))
1578 # ParseResult is a NamedTuple so _replace is standard API
1579 parsed = parsed._replace(**replacements)
1581 if parsed.params or parsed.fragment or parsed.query:
1582 log.warning("Additional items unexpectedly encountered in schemeless URI: %s", parsed.geturl())
1584 return parsed, dirLike