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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
24import contextlib
25import urllib.parse
26import posixpath
27import copy
28import logging
29import re
31from pathlib import Path, PurePath, PurePosixPath
33__all__ = ('ButlerURI',)
35from typing import (
36 TYPE_CHECKING,
37 Any,
38 Iterable,
39 Iterator,
40 List,
41 Optional,
42 Tuple,
43 Type,
44 Union,
45)
47from .utils import NoTransaction
49if TYPE_CHECKING: 49 ↛ 50line 49 didn't jump to line 50, because the condition on line 49 was never true
50 from ..datastore import DatastoreTransaction
53log = logging.getLogger(__name__)
55# Regex for looking for URI escapes
56ESCAPES_RE = re.compile(r"%[A-F0-9]{2}")
58# Precomputed escaped hash
59ESCAPED_HASH = urllib.parse.quote("#")
62class ButlerURI:
63 """Convenience wrapper around URI parsers.
65 Provides access to URI components and can convert file
66 paths into absolute path URIs. Scheme-less URIs are treated as if
67 they are local file system paths and are converted to absolute URIs.
69 A specialist subclass is created for each supported URI scheme.
71 Parameters
72 ----------
73 uri : `str` or `urllib.parse.ParseResult`
74 URI in string form. Can be scheme-less if referring to a local
75 filesystem path.
76 root : `str` or `ButlerURI`, optional
77 When fixing up a relative path in a ``file`` scheme or if scheme-less,
78 use this as the root. Must be absolute. If `None` the current
79 working directory will be used. Can be a file URI.
80 forceAbsolute : `bool`, optional
81 If `True`, scheme-less relative URI will be converted to an absolute
82 path using a ``file`` scheme. If `False` scheme-less URI will remain
83 scheme-less and will not be updated to ``file`` or absolute path.
84 forceDirectory: `bool`, optional
85 If `True` forces the URI to end with a separator, otherwise given URI
86 is interpreted as is.
87 isTemporary : `bool`, optional
88 If `True` indicates that this URI points to a temporary resource.
89 """
91 _pathLib: Type[PurePath] = PurePosixPath
92 """Path library to use for this scheme."""
94 _pathModule = posixpath
95 """Path module to use for this scheme."""
97 transferModes: Tuple[str, ...] = ("copy", "auto", "move")
98 """Transfer modes supported by this implementation.
100 Move is special in that it is generally a copy followed by an unlink.
101 Whether that unlink works depends critically on whether the source URI
102 implements unlink. If it does not the move will be reported as a failure.
103 """
105 transferDefault: str = "copy"
106 """Default mode to use for transferring if ``auto`` is specified."""
108 quotePaths = True
109 """True if path-like elements modifying a URI should be quoted.
111 All non-schemeless URIs have to internally use quoted paths. Therefore
112 if a new file name is given (e.g. to updatedFile or join) a decision must
113 be made whether to quote it to be consistent.
114 """
116 isLocal = False
117 """If `True` this URI refers to a local file."""
119 # This is not an ABC with abstract methods because the __new__ being
120 # a factory confuses mypy such that it assumes that every constructor
121 # returns a ButlerURI and then determines that all the abstract methods
122 # are still abstract. If they are not marked abstract but just raise
123 # mypy is fine with it.
125 # mypy is confused without these
126 _uri: urllib.parse.ParseResult
127 isTemporary: bool
128 dirLike: bool
130 def __new__(cls, uri: Union[str, urllib.parse.ParseResult, ButlerURI, Path],
131 root: Optional[Union[str, ButlerURI]] = None, forceAbsolute: bool = True,
132 forceDirectory: bool = False, isTemporary: bool = False) -> ButlerURI:
133 """Create and return new specialist ButlerURI subclass."""
134 parsed: urllib.parse.ParseResult
135 dirLike: bool = False
136 subclass: Optional[Type[ButlerURI]] = None
138 if isinstance(uri, Path): 138 ↛ 139line 138 didn't jump to line 139, because the condition on line 138 was never true
139 uri = str(uri)
141 # Record if we need to post process the URI components
142 # or if the instance is already fully configured
143 if isinstance(uri, str):
144 # Since local file names can have special characters in them
145 # we need to quote them for the parser but we can unquote
146 # later. Assume that all other URI schemes are quoted.
147 # Since sometimes people write file:/a/b and not file:///a/b
148 # we should not quote in the explicit case of file:
149 if "://" not in uri and not uri.startswith("file:"):
150 if ESCAPES_RE.search(uri): 150 ↛ 151line 150 didn't jump to line 151, because the condition on line 150 was never true
151 log.warning("Possible double encoding of %s", uri)
152 else:
153 uri = urllib.parse.quote(uri)
154 # Special case hash since we must support fragments
155 # even in schemeless URIs -- although try to only replace
156 # them in file part and not directory part
157 if ESCAPED_HASH in uri: 157 ↛ 158line 157 didn't jump to line 158, because the condition on line 157 was never true
158 dirpos = uri.rfind("/")
159 # Do replacement after this /
160 uri = uri[:dirpos+1] + uri[dirpos+1:].replace(ESCAPED_HASH, "#")
162 parsed = urllib.parse.urlparse(uri)
163 elif isinstance(uri, urllib.parse.ParseResult):
164 parsed = copy.copy(uri)
165 # If we are being instantiated with a subclass, rather than
166 # ButlerURI, ensure that that subclass is used directly.
167 # This could lead to inconsistencies if this constructor
168 # is used externally outside of the ButlerURI.replace() method.
169 # ButlerS3URI(urllib.parse.urlparse("file://a/b.txt"))
170 # will be a problem.
171 # This is needed to prevent a schemeless absolute URI become
172 # a file URI unexpectedly when calling updatedFile or
173 # updatedExtension
174 if cls is not ButlerURI:
175 parsed, dirLike = cls._fixDirectorySep(parsed, forceDirectory)
176 subclass = cls
178 elif isinstance(uri, ButlerURI): 178 ↛ 183line 178 didn't jump to line 183, because the condition on line 178 was never false
179 # Since ButlerURI is immutable we can return the argument
180 # unchanged.
181 return uri
182 else:
183 raise ValueError("Supplied URI must be string, Path, "
184 f"ButlerURI, or ParseResult but got '{uri!r}'")
186 if subclass is None:
187 # Work out the subclass from the URI scheme
188 if not parsed.scheme:
189 from .schemeless import ButlerSchemelessURI
190 subclass = ButlerSchemelessURI
191 elif parsed.scheme == "file": 191 ↛ 192line 191 didn't jump to line 192, because the condition on line 191 was never true
192 from .file import ButlerFileURI
193 subclass = ButlerFileURI
194 elif parsed.scheme == "s3": 194 ↛ 195line 194 didn't jump to line 195, because the condition on line 194 was never true
195 from .s3 import ButlerS3URI
196 subclass = ButlerS3URI
197 elif parsed.scheme.startswith("http"): 197 ↛ 198line 197 didn't jump to line 198, because the condition on line 197 was never true
198 from .http import ButlerHttpURI
199 subclass = ButlerHttpURI
200 elif parsed.scheme == "resource": 200 ↛ 204line 200 didn't jump to line 204, because the condition on line 200 was never false
201 # Rules for scheme names disallow pkg_resource
202 from .packageresource import ButlerPackageResourceURI
203 subclass = ButlerPackageResourceURI
204 elif parsed.scheme == "mem":
205 # in-memory datastore object
206 from .mem import ButlerInMemoryURI
207 subclass = ButlerInMemoryURI
208 else:
209 raise NotImplementedError(f"No URI support for scheme: '{parsed.scheme}'"
210 " in {parsed.geturl()}")
212 parsed, dirLike = subclass._fixupPathUri(parsed, root=root,
213 forceAbsolute=forceAbsolute,
214 forceDirectory=forceDirectory)
216 # It is possible for the class to change from schemeless
217 # to file so handle that
218 if parsed.scheme == "file": 218 ↛ 219line 218 didn't jump to line 219, because the condition on line 218 was never true
219 from .file import ButlerFileURI
220 subclass = ButlerFileURI
222 # Now create an instance of the correct subclass and set the
223 # attributes directly
224 self = object.__new__(subclass)
225 self._uri = parsed
226 self.dirLike = dirLike
227 self.isTemporary = isTemporary
228 return self
230 @property
231 def scheme(self) -> str:
232 """Return the URI scheme.
234 Notes
235 -----
236 (``://`` is not part of the scheme).
237 """
238 return self._uri.scheme
240 @property
241 def netloc(self) -> str:
242 """Return the URI network location."""
243 return self._uri.netloc
245 @property
246 def path(self) -> str:
247 """Return the path component of the URI."""
248 return self._uri.path
250 @property
251 def unquoted_path(self) -> str:
252 """Return path component of the URI with any URI quoting reversed."""
253 return urllib.parse.unquote(self._uri.path)
255 @property
256 def ospath(self) -> str:
257 """Return the path component of the URI localized to current OS."""
258 raise AttributeError(f"Non-file URI ({self}) has no local OS path.")
260 @property
261 def relativeToPathRoot(self) -> str:
262 """Return path relative to network location.
264 Effectively, this is the path property with posix separator stripped
265 from the left hand side of the path.
267 Always unquotes.
268 """
269 p = self._pathLib(self.path)
270 relToRoot = str(p.relative_to(p.root))
271 if self.dirLike and not relToRoot.endswith("/"): 271 ↛ 272line 271 didn't jump to line 272, because the condition on line 271 was never true
272 relToRoot += "/"
273 return urllib.parse.unquote(relToRoot)
275 @property
276 def is_root(self) -> bool:
277 """Return whether this URI points to the root of the network location.
279 This means that the path components refers to the top level.
280 """
281 relpath = self.relativeToPathRoot
282 if relpath == "./":
283 return True
284 return False
286 @property
287 def fragment(self) -> str:
288 """Return the fragment component of the URI."""
289 return self._uri.fragment
291 @property
292 def params(self) -> str:
293 """Return any parameters included in the URI."""
294 return self._uri.params
296 @property
297 def query(self) -> str:
298 """Return any query strings included in the URI."""
299 return self._uri.query
301 def geturl(self) -> str:
302 """Return the URI in string form.
304 Returns
305 -------
306 url : `str`
307 String form of URI.
308 """
309 return self._uri.geturl()
311 def root_uri(self) -> ButlerURI:
312 """Return the base root URI.
314 Returns
315 -------
316 uri : `ButlerURI`
317 root URI.
318 """
319 return self.replace(path="", forceDirectory=True)
321 def split(self) -> Tuple[ButlerURI, str]:
322 """Split URI into head and tail.
324 Returns
325 -------
326 head: `ButlerURI`
327 Everything leading up to tail, expanded and normalized as per
328 ButlerURI rules.
329 tail : `str`
330 Last `self.path` component. Tail will be empty if path ends on a
331 separator. Tail will never contain separators. It will be
332 unquoted.
334 Notes
335 -----
336 Equivalent to `os.path.split()` where head preserves the URI
337 components.
338 """
339 head, tail = self._pathModule.split(self.path)
340 headuri = self._uri._replace(path=head)
342 # The file part should never include quoted metacharacters
343 tail = urllib.parse.unquote(tail)
345 # Schemeless is special in that it can be a relative path
346 # We need to ensure that it stays that way. All other URIs will
347 # be absolute already.
348 forceAbsolute = self._pathModule.isabs(self.path)
349 return ButlerURI(headuri, forceDirectory=True, forceAbsolute=forceAbsolute), tail
351 def basename(self) -> str:
352 """Return the base name, last element of path, of the URI.
354 Returns
355 -------
356 tail : `str`
357 Last part of the path attribute. Trail will be empty if path ends
358 on a separator.
360 Notes
361 -----
362 If URI ends on a slash returns an empty string. This is the second
363 element returned by `split()`.
365 Equivalent of `os.path.basename()``.
366 """
367 return self.split()[1]
369 def dirname(self) -> ButlerURI:
370 """Return the directory component of the path as a new `ButlerURI`.
372 Returns
373 -------
374 head : `ButlerURI`
375 Everything except the tail of path attribute, expanded and
376 normalized as per ButlerURI rules.
378 Notes
379 -----
380 Equivalent of `os.path.dirname()`.
381 """
382 return self.split()[0]
384 def parent(self) -> ButlerURI:
385 """Return a `ButlerURI` of the parent directory.
387 Returns
388 -------
389 head : `ButlerURI`
390 Everything except the tail of path attribute, expanded and
391 normalized as per `ButlerURI` rules.
393 Notes
394 -----
395 For a file-like URI this will be the same as calling `dirname()`.
396 """
397 # When self is file-like, return self.dirname()
398 if not self.dirLike:
399 return self.dirname()
400 # When self is dir-like, return its parent directory,
401 # regardless of the presence of a trailing separator
402 originalPath = self._pathLib(self.path)
403 parentPath = originalPath.parent
404 return self.replace(path=str(parentPath), forceDirectory=True)
406 def replace(self, forceDirectory: bool = False, **kwargs: Any) -> ButlerURI:
407 """Return new `ButlerURI` with specified components replaced.
409 Parameters
410 ----------
411 forceDirectory : `bool`
412 Parameter passed to ButlerURI constructor to force this
413 new URI to be dir-like.
414 **kwargs
415 Components of a `urllib.parse.ParseResult` that should be
416 modified for the newly-created `ButlerURI`.
418 Returns
419 -------
420 new : `ButlerURI`
421 New `ButlerURI` object with updated values.
423 Notes
424 -----
425 Does not, for now, allow a change in URI scheme.
426 """
427 # Disallow a change in scheme
428 if "scheme" in kwargs: 428 ↛ 429line 428 didn't jump to line 429, because the condition on line 428 was never true
429 raise ValueError(f"Can not use replace() method to change URI scheme for {self}")
430 return self.__class__(self._uri._replace(**kwargs), forceDirectory=forceDirectory)
432 def updatedFile(self, newfile: str) -> ButlerURI:
433 """Return new URI with an updated final component of the path.
435 Parameters
436 ----------
437 newfile : `str`
438 File name with no path component.
440 Returns
441 -------
442 updated : `ButlerURI`
444 Notes
445 -----
446 Forces the ButlerURI.dirLike attribute to be false. The new file path
447 will be quoted if necessary.
448 """
449 if self.quotePaths:
450 newfile = urllib.parse.quote(newfile)
451 dir, _ = self._pathModule.split(self.path)
452 newpath = self._pathModule.join(dir, newfile)
454 updated = self.replace(path=newpath)
455 updated.dirLike = False
456 return updated
458 def updatedExtension(self, ext: Optional[str]) -> ButlerURI:
459 """Return a new `ButlerURI` with updated file extension.
461 All file extensions are replaced.
463 Parameters
464 ----------
465 ext : `str` or `None`
466 New extension. If an empty string is given any extension will
467 be removed. If `None` is given there will be no change.
469 Returns
470 -------
471 updated : `ButlerURI`
472 URI with the specified extension. Can return itself if
473 no extension was specified.
474 """
475 if ext is None:
476 return self
478 # Get the extension
479 current = self.getExtension()
481 # Nothing to do if the extension already matches
482 if current == ext:
483 return self
485 # Remove the current extension from the path
486 # .fits.gz counts as one extension do not use os.path.splitext
487 path = self.path
488 if current:
489 path = path[:-len(current)]
491 # Ensure that we have a leading "." on file extension (and we do not
492 # try to modify the empty string)
493 if ext and not ext.startswith("."):
494 ext = "." + ext
496 return self.replace(path=path + ext)
498 def getExtension(self) -> str:
499 """Return the file extension(s) associated with this URI path.
501 Returns
502 -------
503 ext : `str`
504 The file extension (including the ``.``). Can be empty string
505 if there is no file extension. Usually returns only the last
506 file extension unless there is a special extension modifier
507 indicating file compression, in which case the combined
508 extension (e.g. ``.fits.gz``) will be returned.
509 """
510 special = {".gz", ".bz2", ".xz", ".fz"}
512 # Get the file part of the path so as not to be confused by
513 # "." in directory names.
514 basename = self.basename()
515 extensions = self._pathLib(basename).suffixes
517 if not extensions: 517 ↛ 518line 517 didn't jump to line 518, because the condition on line 517 was never true
518 return ""
520 ext = extensions.pop()
522 # Multiple extensions, decide whether to include the final two
523 if extensions and ext in special: 523 ↛ 524line 523 didn't jump to line 524, because the condition on line 523 was never true
524 ext = f"{extensions[-1]}{ext}"
526 return ext
528 def join(self, path: Union[str, ButlerURI]) -> ButlerURI:
529 """Return new `ButlerURI` with additional path components.
531 Parameters
532 ----------
533 path : `str`, `ButlerURI`
534 Additional file components to append to the current URI. Assumed
535 to include a file at the end. Will be quoted depending on the
536 associated URI scheme. If the path looks like a URI with a scheme
537 referring to an absolute location, it will be returned
538 directly (matching the behavior of `os.path.join()`). It can
539 also be a `ButlerURI`.
541 Returns
542 -------
543 new : `ButlerURI`
544 New URI with any file at the end replaced with the new path
545 components.
547 Notes
548 -----
549 Schemeless URIs assume local path separator but all other URIs assume
550 POSIX separator if the supplied path has directory structure. It
551 may be this never becomes a problem but datastore templates assume
552 POSIX separator is being used.
554 If an absolute `ButlerURI` is given for ``path`` is is assumed that
555 this should be returned directly. Giving a ``path`` of an absolute
556 scheme-less URI is not allowed for safety reasons as it may indicate
557 a mistake in the calling code.
559 Raises
560 ------
561 ValueError
562 Raised if the ``path`` is an absolute scheme-less URI. In that
563 situation it is unclear whether the intent is to return a
564 ``file`` URI or it was a mistake and a relative scheme-less URI
565 was meant.
566 """
567 # If we have a full URI in path we will use it directly
568 # but without forcing to absolute so that we can trap the
569 # expected option of relative path.
570 path_uri = ButlerURI(path, forceAbsolute=False)
571 if path_uri.scheme: 571 ↛ 574line 571 didn't jump to line 574, because the condition on line 571 was never true
572 # Check for scheme so can distinguish explicit URIs from
573 # absolute scheme-less URIs.
574 return path_uri
576 if path_uri.isabs(): 576 ↛ 578line 576 didn't jump to line 578, because the condition on line 576 was never true
577 # Absolute scheme-less path.
578 raise ValueError(f"Can not join absolute scheme-less {path_uri!r} to another URI.")
580 # If this was originally a ButlerURI extract the unquoted path from it.
581 # Otherwise we use the string we were given to allow "#" to appear
582 # in the filename if given as a plain string.
583 if not isinstance(path, str): 583 ↛ 584line 583 didn't jump to line 584, because the condition on line 583 was never true
584 path = path_uri.unquoted_path
586 new = self.dirname() # By definition a directory URI
588 # new should be asked about quoting, not self, since dirname can
589 # change the URI scheme for schemeless -> file
590 if new.quotePaths: 590 ↛ 593line 590 didn't jump to line 593, because the condition on line 590 was never false
591 path = urllib.parse.quote(path)
593 newpath = self._pathModule.normpath(self._pathModule.join(new.path, path))
595 # normpath can strip trailing / so we force directory if the supplied
596 # path ended with a /
597 return new.replace(path=newpath, forceDirectory=path.endswith(self._pathModule.sep))
599 def relative_to(self, other: ButlerURI) -> Optional[str]:
600 """Return the relative path from this URI to the other URI.
602 Parameters
603 ----------
604 other : `ButlerURI`
605 URI to use to calculate the relative path. Must be a parent
606 of this URI.
608 Returns
609 -------
610 subpath : `str`
611 The sub path of this URI relative to the supplied other URI.
612 Returns `None` if there is no parent child relationship.
613 Scheme and netloc must match.
614 """
615 # Scheme-less absolute other is treated as if it's a file scheme.
616 # Scheme-less relative other can only return non-None if self
617 # is also scheme-less relative and that is handled specifically
618 # in a subclass.
619 if not other.scheme and other.isabs():
620 other = other.abspath()
622 # Scheme-less self is handled elsewhere.
623 if self.scheme != other.scheme or self.netloc != other.netloc:
624 return None
626 enclosed_path = self._pathLib(self.relativeToPathRoot)
627 parent_path = other.relativeToPathRoot
628 subpath: Optional[str]
629 try:
630 subpath = str(enclosed_path.relative_to(parent_path))
631 except ValueError:
632 subpath = None
633 else:
634 subpath = urllib.parse.unquote(subpath)
635 return subpath
637 def exists(self) -> bool:
638 """Indicate that the resource is available.
640 Returns
641 -------
642 exists : `bool`
643 `True` if the resource exists.
644 """
645 raise NotImplementedError()
647 def remove(self) -> None:
648 """Remove the resource."""
649 raise NotImplementedError()
651 def isabs(self) -> bool:
652 """Indicate that the resource is fully specified.
654 For non-schemeless URIs this is always true.
656 Returns
657 -------
658 isabs : `bool`
659 `True` in all cases except schemeless URI.
660 """
661 return True
663 def abspath(self) -> ButlerURI:
664 """Return URI using an absolute path.
666 Returns
667 -------
668 abs : `ButlerURI`
669 Absolute URI. For non-schemeless URIs this always returns itself.
670 Schemeless URIs are upgraded to file URIs.
671 """
672 return self
674 def _as_local(self) -> Tuple[str, bool]:
675 """Return the location of the (possibly remote) resource as local file.
677 This is a helper function for `as_local` context manager.
679 Returns
680 -------
681 path : `str`
682 If this is a remote resource, it will be a copy of the resource
683 on the local file system, probably in a temporary directory.
684 For a local resource this should be the actual path to the
685 resource.
686 is_temporary : `bool`
687 Indicates if the local path is a temporary file or not.
688 """
689 raise NotImplementedError()
691 @contextlib.contextmanager
692 def as_local(self) -> Iterator[ButlerURI]:
693 """Return the location of the (possibly remote) resource as local file.
695 Yields
696 ------
697 local : `ButlerURI`
698 If this is a remote resource, it will be a copy of the resource
699 on the local file system, probably in a temporary directory.
700 For a local resource this should be the actual path to the
701 resource.
703 Notes
704 -----
705 The context manager will automatically delete any local temporary
706 file.
708 Examples
709 --------
710 Should be used as a context manager:
712 .. code-block:: py
714 with uri.as_local() as local:
715 ospath = local.ospath
716 """
717 local_src, is_temporary = self._as_local()
718 local_uri = ButlerURI(local_src, isTemporary=is_temporary)
720 try:
721 yield local_uri
722 finally:
723 # The caller might have relocated the temporary file
724 if is_temporary and local_uri.exists():
725 local_uri.remove()
727 def read(self, size: int = -1) -> bytes:
728 """Open the resource and return the contents in bytes.
730 Parameters
731 ----------
732 size : `int`, optional
733 The number of bytes to read. Negative or omitted indicates
734 that all data should be read.
735 """
736 raise NotImplementedError()
738 def write(self, data: bytes, overwrite: bool = True) -> None:
739 """Write the supplied bytes to the new resource.
741 Parameters
742 ----------
743 data : `bytes`
744 The bytes to write to the resource. The entire contents of the
745 resource will be replaced.
746 overwrite : `bool`, optional
747 If `True` the resource will be overwritten if it exists. Otherwise
748 the write will fail.
749 """
750 raise NotImplementedError()
752 def mkdir(self) -> None:
753 """For a dir-like URI, create the directory resource if needed."""
754 raise NotImplementedError()
756 def isdir(self) -> bool:
757 """Return True if this URI looks like a directory, else False."""
758 return self.dirLike
760 def size(self) -> int:
761 """For non-dir-like URI, return the size of the resource.
763 Returns
764 -------
765 sz : `int`
766 The size in bytes of the resource associated with this URI.
767 Returns 0 if dir-like.
768 """
769 raise NotImplementedError()
771 def __str__(self) -> str:
772 """Convert the URI to its native string form."""
773 return self.geturl()
775 def __repr__(self) -> str:
776 """Return string representation suitable for evaluation."""
777 return f'ButlerURI("{self.geturl()}")'
779 def __eq__(self, other: Any) -> bool:
780 """Compare supplied object with this `ButlerURI`."""
781 if not isinstance(other, ButlerURI):
782 return NotImplemented
783 return self.geturl() == other.geturl()
785 def __hash__(self) -> int:
786 """Return hash of this object."""
787 return hash(str(self))
789 def __copy__(self) -> ButlerURI:
790 """Copy constructor.
792 Object is immutable so copy can return itself.
793 """
794 # Implement here because the __new__ method confuses things
795 return self
797 def __deepcopy__(self, memo: Any) -> ButlerURI:
798 """Deepcopy the object.
800 Object is immutable so copy can return itself.
801 """
802 # Implement here because the __new__ method confuses things
803 return self
805 def __getnewargs__(self) -> Tuple:
806 """Support pickling."""
807 return (str(self),)
809 @classmethod
810 def _fixDirectorySep(cls, parsed: urllib.parse.ParseResult,
811 forceDirectory: bool = False) -> Tuple[urllib.parse.ParseResult, bool]:
812 """Ensure that a path separator is present on directory paths.
814 Parameters
815 ----------
816 parsed : `~urllib.parse.ParseResult`
817 The result from parsing a URI using `urllib.parse`.
818 forceDirectory : `bool`, optional
819 If `True` forces the URI to end with a separator, otherwise given
820 URI is interpreted as is. Specifying that the URI is conceptually
821 equivalent to a directory can break some ambiguities when
822 interpreting the last element of a path.
824 Returns
825 -------
826 modified : `~urllib.parse.ParseResult`
827 Update result if a URI is being handled.
828 dirLike : `bool`
829 `True` if given parsed URI has a trailing separator or
830 forceDirectory is True. Otherwise `False`.
831 """
832 # assume we are not dealing with a directory like URI
833 dirLike = False
835 # Directory separator
836 sep = cls._pathModule.sep
838 # URI is dir-like if explicitly stated or if it ends on a separator
839 endsOnSep = parsed.path.endswith(sep)
840 if forceDirectory or endsOnSep:
841 dirLike = True
842 # only add the separator if it's not already there
843 if not endsOnSep: 843 ↛ 846line 843 didn't jump to line 846, because the condition on line 843 was never false
844 parsed = parsed._replace(path=parsed.path+sep)
846 return parsed, dirLike
848 @classmethod
849 def _fixupPathUri(cls, parsed: urllib.parse.ParseResult, root: Optional[Union[str, ButlerURI]] = None,
850 forceAbsolute: bool = False,
851 forceDirectory: bool = False) -> Tuple[urllib.parse.ParseResult, bool]:
852 """Correct any issues with the supplied URI.
854 Parameters
855 ----------
856 parsed : `~urllib.parse.ParseResult`
857 The result from parsing a URI using `urllib.parse`.
858 root : `str` or `ButlerURI`, ignored
859 Not used by the this implementation since all URIs are
860 absolute except for those representing the local file system.
861 forceAbsolute : `bool`, ignored.
862 Not used by this implementation. URIs are generally always
863 absolute.
864 forceDirectory : `bool`, optional
865 If `True` forces the URI to end with a separator, otherwise given
866 URI is interpreted as is. Specifying that the URI is conceptually
867 equivalent to a directory can break some ambiguities when
868 interpreting the last element of a path.
870 Returns
871 -------
872 modified : `~urllib.parse.ParseResult`
873 Update result if a URI is being handled.
874 dirLike : `bool`
875 `True` if given parsed URI has a trailing separator or
876 forceDirectory is True. Otherwise `False`.
878 Notes
879 -----
880 Relative paths are explicitly not supported by RFC8089 but `urllib`
881 does accept URIs of the form ``file:relative/path.ext``. They need
882 to be turned into absolute paths before they can be used. This is
883 always done regardless of the ``forceAbsolute`` parameter.
885 AWS S3 differentiates between keys with trailing POSIX separators (i.e
886 `/dir` and `/dir/`) whereas POSIX does not neccessarily.
888 Scheme-less paths are normalized.
889 """
890 return cls._fixDirectorySep(parsed, forceDirectory)
892 def transfer_from(self, src: ButlerURI, transfer: str,
893 overwrite: bool = False,
894 transaction: Optional[Union[DatastoreTransaction, NoTransaction]] = None) -> None:
895 """Transfer the current resource to a new location.
897 Parameters
898 ----------
899 src : `ButlerURI`
900 Source URI.
901 transfer : `str`
902 Mode to use for transferring the resource. Generically there are
903 many standard options: copy, link, symlink, hardlink, relsymlink.
904 Not all URIs support all modes.
905 overwrite : `bool`, optional
906 Allow an existing file to be overwritten. Defaults to `False`.
907 transaction : `DatastoreTransaction`, optional
908 A transaction object that can (depending on implementation)
909 rollback transfers on error. Not guaranteed to be implemented.
911 Notes
912 -----
913 Conceptually this is hard to scale as the number of URI schemes
914 grow. The destination URI is more important than the source URI
915 since that is where all the transfer modes are relevant (with the
916 complication that "move" deletes the source).
918 Local file to local file is the fundamental use case but every
919 other scheme has to support "copy" to local file (with implicit
920 support for "move") and copy from local file.
921 All the "link" options tend to be specific to local file systems.
923 "move" is a "copy" where the remote resource is deleted at the end.
924 Whether this works depends on the source URI rather than the
925 destination URI. Reverting a move on transaction rollback is
926 expected to be problematic if a remote resource was involved.
927 """
928 raise NotImplementedError(f"No transfer modes supported by URI scheme {self.scheme}")
930 def walk(self, file_filter: Optional[Union[str, re.Pattern]] = None) -> Iterator[Union[List,
931 Tuple[ButlerURI,
932 List[str],
933 List[str]]]]:
934 """Walk the directory tree returning matching files and directories.
936 Parameters
937 ----------
938 file_filter : `str` or `re.Pattern`, optional
939 Regex to filter out files from the list before it is returned.
941 Yields
942 ------
943 dirpath : `ButlerURI`
944 Current directory being examined.
945 dirnames : `list` of `str`
946 Names of subdirectories within dirpath.
947 filenames : `list` of `str`
948 Names of all the files within dirpath.
949 """
950 raise NotImplementedError()
952 @classmethod
953 def findFileResources(cls, candidates: Iterable[Union[str, ButlerURI]],
954 file_filter: Optional[str] = None,
955 grouped: bool = False) -> Iterator[Union[ButlerURI, Iterator[ButlerURI]]]:
956 """Get all the files from a list of values.
958 Parameters
959 ----------
960 candidates : iterable [`str` or `ButlerURI`]
961 The files to return and directories in which to look for files to
962 return.
963 file_filter : `str`, optional
964 The regex to use when searching for files within directories.
965 By default returns all the found files.
966 grouped : `bool`, optional
967 If `True` the results will be grouped by directory and each
968 yielded value will be an iterator over URIs. If `False` each
969 URI will be returned separately.
971 Yields
972 ------
973 found_file: `ButlerURI`
974 The passed-in URIs and URIs found in passed-in directories.
975 If grouping is enabled, each of the yielded values will be an
976 iterator yielding members of the group. Files given explicitly
977 will be returned as a single group at the end.
979 Notes
980 -----
981 If a value is a file it is yielded immediately. If a value is a
982 directory, all the files in the directory (recursively) that match
983 the regex will be yielded in turn.
984 """
985 fileRegex = None if file_filter is None else re.compile(file_filter)
987 singles = []
989 # Find all the files of interest
990 for location in candidates:
991 uri = ButlerURI(location)
992 if uri.isdir():
993 for found in uri.walk(fileRegex):
994 if not found:
995 # This means the uri does not exist and by
996 # convention we ignore it
997 continue
998 root, dirs, files = found
999 if not files:
1000 continue
1001 if grouped:
1002 yield (root.join(name) for name in files)
1003 else:
1004 for name in files:
1005 yield root.join(name)
1006 else:
1007 if grouped:
1008 singles.append(uri)
1009 else:
1010 yield uri
1012 # Finally, return any explicitly given files in one group
1013 if grouped and singles:
1014 yield iter(singles)