Coverage for python/lsst/daf/butler/core/location.py: 25%
81 statements
« prev ^ index » next coverage.py v7.2.7, created at 2023-06-14 09:11 +0000
« prev ^ index » next coverage.py v7.2.7, created at 2023-06-14 09:11 +0000
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")
26from lsst.resources import ResourcePath, ResourcePathExpression
29class Location:
30 """Identifies a location within the `Datastore`.
32 Parameters
33 ----------
34 datastoreRootUri : `lsst.resources.ResourcePathExpression` or `None`
35 Base URI for this datastore, must include an absolute path.
36 If `None` the `path` must correspond to an absolute URI.
37 path : `lsst.resources.ResourcePathExpression`
38 Relative path within datastore. Assumed to be using the local
39 path separator if a ``file`` scheme is being used for the URI,
40 else a POSIX separator. Can be a full URI if the root URI is `None`.
41 Can also be a schemeless URI if it refers to a relative path.
42 """
44 __slots__ = ("_datastoreRootUri", "_path", "_uri")
46 def __init__(self, datastoreRootUri: None | ResourcePathExpression, path: ResourcePathExpression):
47 # Be careful not to force a relative local path to absolute path
48 path_uri = ResourcePath(path, forceAbsolute=False)
50 if isinstance(datastoreRootUri, str):
51 datastoreRootUri = ResourcePath(datastoreRootUri, forceDirectory=True)
52 elif datastoreRootUri is None:
53 if not path_uri.isabs():
54 raise ValueError(f"No datastore root URI given but path '{path}' was not absolute URI.")
55 elif not isinstance(datastoreRootUri, ResourcePath):
56 raise ValueError("Datastore root must be a ResourcePath instance")
58 if datastoreRootUri is not None and not datastoreRootUri.isabs():
59 raise ValueError(f"Supplied root URI must be an absolute path (given {datastoreRootUri}).")
61 self._datastoreRootUri = datastoreRootUri
63 # if the root URI is not None the path must not be absolute since
64 # it is required to be within the root.
65 if datastoreRootUri is not None:
66 if path_uri.isabs():
67 raise ValueError(f"Path within datastore must be relative not absolute, got {path_uri}")
69 self._path = path_uri
71 # Internal cache of the full location as a ResourcePath
72 self._uri: ResourcePath | None = None
74 # Check that the resulting URI is inside the datastore
75 # This can go wrong if we were given ../dir as path
76 if self._datastoreRootUri is not None:
77 pathInStore = self.uri.relative_to(self._datastoreRootUri)
78 if pathInStore is None:
79 raise ValueError(f"Unexpectedly {path} jumps out of {self._datastoreRootUri}")
81 def __str__(self) -> str:
82 return str(self.uri)
84 def __repr__(self) -> str:
85 uri = self._datastoreRootUri
86 path = self._path
87 return f"{self.__class__.__name__}({uri!r}, {path.path!r})"
89 def __eq__(self, other: object) -> bool:
90 if not isinstance(other, Location):
91 return NotImplemented
92 # Compare the combined URI rather than how it is apportioned
93 return self.uri == other.uri
95 @property
96 def uri(self) -> ResourcePath:
97 """Return URI corresponding to fully-specified datastore location."""
98 if self._uri is None:
99 root = self._datastoreRootUri
100 if root is None:
101 uri = self._path
102 else:
103 uri = root.join(self._path)
104 self._uri = uri
105 return self._uri
107 @property
108 def path(self) -> str:
109 """Return path corresponding to location.
111 This path includes the root of the `Datastore`, but does not include
112 non-path components of the root URI. Paths will not include URI
113 quoting. If a file URI scheme is being used the path will be returned
114 with the local OS path separator.
115 """
116 full = self.uri
117 try:
118 return full.ospath
119 except AttributeError:
120 return full.unquoted_path
122 @property
123 def pathInStore(self) -> ResourcePath:
124 """Return path corresponding to location relative to `Datastore` root.
126 Uses the same path separator as supplied to the object constructor.
127 Can be an absolute URI if that is how the location was configured.
128 """
129 return self._path
131 @property
132 def netloc(self) -> str:
133 """Return the URI network location."""
134 return self.uri.netloc
136 @property
137 def relativeToPathRoot(self) -> str:
138 """Return the path component relative to the network location.
140 Effectively, this is the path property with POSIX separator stripped
141 from the left hand side of the path. Will be unquoted.
142 """
143 return self.uri.relativeToPathRoot
145 def updateExtension(self, ext: str | None) -> None:
146 """Update the file extension associated with this `Location`.
148 All file extensions are replaced.
150 Parameters
151 ----------
152 ext : `str`
153 New extension. If an empty string is given any extension will
154 be removed. If `None` is given there will be no change.
155 """
156 if ext is None:
157 return
159 self._path = self._path.updatedExtension(ext)
161 # Clear the URI cache so it can be recreated with the new path
162 self._uri = None
164 def getExtension(self) -> str:
165 """Return the file extension(s) associated with this location.
167 Returns
168 -------
169 ext : `str`
170 The file extension (including the ``.``). Can be empty string
171 if there is no file extension. Will return all file extensions
172 as a single extension such that ``file.fits.gz`` will return
173 a value of ``.fits.gz``.
174 """
175 return self.uri.getExtension()
178class LocationFactory:
179 """Factory for `Location` instances.
181 The factory is constructed from the root location of the datastore.
182 This location can be a path on the file system (absolute or relative)
183 or as a URI.
185 Parameters
186 ----------
187 datastoreRoot : `str`
188 Root location of the `Datastore` either as a path in the local
189 filesystem or as a URI. File scheme URIs can be used. If a local
190 filesystem path is used without URI scheme, it will be converted
191 to an absolute path and any home directory indicators expanded.
192 If a file scheme is used with a relative path, the path will
193 be treated as a posixpath but then converted to an absolute path.
194 """
196 def __init__(self, datastoreRoot: ResourcePathExpression):
197 self._datastoreRootUri = ResourcePath(datastoreRoot, forceAbsolute=True, forceDirectory=True)
199 def __str__(self) -> str:
200 return f"{self.__class__.__name__}@{self._datastoreRootUri}"
202 @property
203 def netloc(self) -> str:
204 """Return the network location of root location of the `Datastore`."""
205 return self._datastoreRootUri.netloc
207 def fromPath(self, path: ResourcePathExpression) -> Location:
208 """Create a `Location` from a POSIX path.
210 Parameters
211 ----------
212 path : `str` or `lsst.resources.ResourcePath`
213 A standard POSIX path, relative to the `Datastore` root.
214 If it is a `lsst.resources.ResourcePath` it must not be absolute.
216 Returns
217 -------
218 location : `Location`
219 The equivalent `Location`.
220 """
221 path = ResourcePath(path, forceAbsolute=False)
222 if path.isabs():
223 raise ValueError("LocationFactory path must be relative to datastore, not absolute.")
224 return Location(self._datastoreRootUri, path)