Coverage for python/lsst/daf/butler/core/location.py : 27%

Hot-keys on this page
r m x p toggle line displays
j k next/prev highlighted chunk
0 (zero) top of page
1 (one) first highlighted chunk
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__ = ("Location", "LocationFactory")
26import os
27import os.path
29from typing import (
30 Optional,
31 Union,
32)
34from ._butlerUri import ButlerURI
37class Location:
38 """Identifies a location within the `Datastore`.
40 Parameters
41 ----------
42 datastoreRootUri : `ButlerURI` or `str` or `None`
43 Base URI for this datastore, must include an absolute path.
44 If `None` the `path` must correspond to an absolute URI.
45 path : `ButlerURI` or `str`
46 Relative path within datastore. Assumed to be using the local
47 path separator if a ``file`` scheme is being used for the URI,
48 else a POSIX separator. Can be a full URI if the root URI is `None`.
49 Can also be a schemeless URI if it refers to a relative path.
50 """
52 __slots__ = ("_datastoreRootUri", "_path", "_uri")
54 def __init__(self, datastoreRootUri: Union[None, ButlerURI, str],
55 path: Union[ButlerURI, str]):
56 # Be careful not to force a relative local path to absolute path
57 path_uri = ButlerURI(path, forceAbsolute=False)
59 if isinstance(datastoreRootUri, str):
60 datastoreRootUri = ButlerURI(datastoreRootUri, forceDirectory=True)
61 elif datastoreRootUri is None:
62 if not path_uri.isabs():
63 raise ValueError(f"No datastore root URI given but path '{path}' was not absolute URI.")
64 elif not isinstance(datastoreRootUri, ButlerURI):
65 raise ValueError("Datastore root must be a ButlerURI instance")
67 if datastoreRootUri is not None and not datastoreRootUri.isabs():
68 raise ValueError(f"Supplied root URI must be an absolute path (given {datastoreRootUri}).")
70 self._datastoreRootUri = datastoreRootUri
72 # if the root URI is not None the path must not be absolute since
73 # it is required to be within the root.
74 if datastoreRootUri is not None:
75 if path_uri.isabs():
76 raise ValueError(f"Path within datastore must be relative not absolute, got {path_uri}")
78 self._path = path_uri
80 # Internal cache of the full location as a ButlerURI
81 self._uri: Optional[ButlerURI] = None
83 # Check that the resulting URI is inside the datastore
84 # This can go wrong if we were given ../dir as path
85 if self._datastoreRootUri is not None:
86 pathInStore = self.uri.relative_to(self._datastoreRootUri)
87 if pathInStore is None:
88 raise ValueError(f"Unexpectedly {path} jumps out of {self._datastoreRootUri}")
90 def __str__(self) -> str:
91 return str(self.uri)
93 def __repr__(self) -> str:
94 uri = self._datastoreRootUri
95 path = self._path
96 return f"{self.__class__.__name__}({uri!r}, {path.path!r})"
98 def __eq__(self, other: object) -> bool:
99 if not isinstance(other, Location):
100 return NotImplemented
101 # Compare the combined URI rather than how it is apportioned
102 return self.uri == other.uri
104 @property
105 def uri(self) -> ButlerURI:
106 """URI corresponding to fully-specified location in datastore.
107 """
108 if self._uri is None:
109 root = self._datastoreRootUri
110 if root is None:
111 uri = self._path
112 else:
113 uri = root.join(self._path)
114 self._uri = uri
115 return self._uri
117 @property
118 def path(self) -> str:
119 """Path corresponding to location.
121 This path includes the root of the `Datastore`, but does not include
122 non-path components of the root URI. Paths will not include URI
123 quoting. If a file URI scheme is being used the path will be returned
124 with the local OS path separator.
125 """
126 full = self.uri
127 try:
128 return full.ospath
129 except AttributeError:
130 return full.unquoted_path
132 @property
133 def pathInStore(self) -> ButlerURI:
134 """Path corresponding to location relative to `Datastore` root.
136 Uses the same path separator as supplied to the object constructor.
137 Can be an absolute URI if that is how the location was configured.
138 """
139 return self._path
141 @property
142 def netloc(self) -> str:
143 """The URI network location."""
144 return self.uri.netloc
146 @property
147 def relativeToPathRoot(self) -> str:
148 """Returns the path component of the URI relative to the network
149 location.
151 Effectively, this is the path property with POSIX separator stripped
152 from the left hand side of the path. Will be unquoted.
153 """
154 return self.uri.relativeToPathRoot
156 def updateExtension(self, ext: Optional[str]) -> None:
157 """Update the file extension associated with this `Location`.
159 All file extensions are replaced.
161 Parameters
162 ----------
163 ext : `str`
164 New extension. If an empty string is given any extension will
165 be removed. If `None` is given there will be no change.
166 """
167 if ext is None:
168 return
170 self._path.updateExtension(ext)
172 # Clear the URI cache so it can be recreated with the new path
173 self._uri = None
175 def getExtension(self) -> str:
176 """Return the file extension(s) associated with this location.
178 Returns
179 -------
180 ext : `str`
181 The file extension (including the ``.``). Can be empty string
182 if there is no file extension. Will return all file extensions
183 as a single extension such that ``file.fits.gz`` will return
184 a value of ``.fits.gz``.
185 """
186 return self.uri.getExtension()
189class LocationFactory:
190 """Factory for `Location` instances.
192 The factory is constructed from the root location of the datastore.
193 This location can be a path on the file system (absolute or relative)
194 or as a URI.
196 Parameters
197 ----------
198 datastoreRoot : `str`
199 Root location of the `Datastore` either as a path in the local
200 filesystem or as a URI. File scheme URIs can be used. If a local
201 filesystem path is used without URI scheme, it will be converted
202 to an absolute path and any home directory indicators expanded.
203 If a file scheme is used with a relative path, the path will
204 be treated as a posixpath but then converted to an absolute path.
205 """
207 def __init__(self, datastoreRoot: Union[ButlerURI, str]):
208 self._datastoreRootUri = ButlerURI(datastoreRoot, forceAbsolute=True,
209 forceDirectory=True)
211 def __str__(self) -> str:
212 return f"{self.__class__.__name__}@{self._datastoreRootUri}"
214 @property
215 def netloc(self) -> str:
216 """Returns the network location of root location of the `Datastore`."""
217 return self._datastoreRootUri.netloc
219 def fromPath(self, path: str) -> Location:
220 """Factory function to create a `Location` from a POSIX path.
222 Parameters
223 ----------
224 path : `str`
225 A standard POSIX path, relative to the `Datastore` root.
227 Returns
228 -------
229 location : `Location`
230 The equivalent `Location`.
231 """
232 if os.path.isabs(path):
233 raise ValueError("LocationFactory path must be relative to datastore, not absolute.")
234 return Location(self._datastoreRootUri, path)