Coverage for python/lsst/daf/butler/core/config.py : 42%

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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"""Configuration control."""
26__all__ = ("Config", "ConfigSubset")
28import collections
29import copy
30import json
31import logging
32import pprint
33import os
34import yaml
35import sys
36from pathlib import Path
37from yaml.representer import Representer
38import io
39from typing import Any, Dict, List, Sequence, Optional, ClassVar, IO, Tuple, Union
41from lsst.utils import doImport
42from ._butlerUri import ButlerURI
44yaml.add_representer(collections.defaultdict, Representer.represent_dict)
47# Config module logger
48log = logging.getLogger(__name__)
50# PATH-like environment variable to use for defaults.
51CONFIG_PATH = "DAF_BUTLER_CONFIG_PATH"
53try:
54 yamlLoader = yaml.CSafeLoader
55except AttributeError:
56 # Not all installations have the C library
57 # (but assume for mypy's sake that they're the same)
58 yamlLoader = yaml.SafeLoader # type: ignore
61class Loader(yamlLoader):
62 """YAML Loader that supports file include directives.
64 Uses ``!include`` directive in a YAML file to point to another
65 YAML file to be included. The path in the include directive is relative
66 to the file containing that directive.
68 storageClasses: !include storageClasses.yaml
70 Examples
71 --------
72 >>> with open("document.yaml", "r") as f:
73 data = yaml.load(f, Loader=Loader)
75 Notes
76 -----
77 See https://davidchall.github.io/yaml-includes.html
78 """
80 def __init__(self, stream):
81 super().__init__(stream)
82 # if this is a string and not a stream we may well lack a name
83 try:
84 self._root = ButlerURI(stream.name)
85 except AttributeError:
86 # No choice but to assume a local filesystem
87 self._root = ButlerURI("no-file.yaml")
88 Loader.add_constructor("!include", Loader.include)
90 def include(self, node):
91 result: Union[List[Any], Dict[str, Any]]
92 if isinstance(node, yaml.ScalarNode):
93 return self.extractFile(self.construct_scalar(node))
95 elif isinstance(node, yaml.SequenceNode):
96 result = []
97 for filename in self.construct_sequence(node):
98 result.append(self.extractFile(filename))
99 return result
101 elif isinstance(node, yaml.MappingNode):
102 result = {}
103 for k, v in self.construct_mapping(node).items():
104 result[k] = self.extractFile(v)
105 return result
107 else:
108 print("Error:: unrecognised node type in !include statement", file=sys.stderr)
109 raise yaml.constructor.ConstructorError
111 def extractFile(self, filename):
112 # It is possible for the !include to point to an explicit URI
113 # instead of a relative URI, therefore we first see if it is
114 # scheme-less or not. If it has a scheme we use it directly
115 # if it is scheme-less we use it relative to the file root.
116 requesteduri = ButlerURI(filename, forceAbsolute=False)
118 if requesteduri.scheme:
119 fileuri = requesteduri
120 else:
121 fileuri = self._root.updatedFile(filename)
123 log.debug("Opening YAML file via !include: %s", fileuri)
125 # Read all the data from the resource
126 data = fileuri.read()
128 # Store the bytes into a BytesIO so we can attach a .name
129 stream = io.BytesIO(data)
130 stream.name = fileuri.geturl()
131 return yaml.load(stream, Loader)
134class Config(collections.abc.MutableMapping):
135 r"""Implements a datatype that is used by `Butler` for configuration.
137 It is essentially a `dict` with key/value pairs, including nested dicts
138 (as values). In fact, it can be initialized with a `dict`.
139 This is explained next:
141 Config extends the `dict` api so that hierarchical values may be accessed
142 with delimited notation or as a tuple. If a string is given the delimiter
143 is picked up from the first character in that string. For example,
144 ``foo.getValue(".a.b.c")``, ``foo["a"]["b"]["c"]``, ``foo["a", "b", "c"]``,
145 ``foo[".a.b.c"]``, and ``foo["/a/b/c"]`` all achieve the same outcome.
146 If the first character is alphanumeric, no delimiter will be used.
147 ``foo["a.b.c"]`` will be a single key ``a.b.c`` as will ``foo[":a.b.c"]``.
148 Unicode characters can be used as the delimiter for distinctiveness if
149 required.
151 If a key in the hierarchy starts with a non-alphanumeric character care
152 should be used to ensure that either the tuple interface is used or
153 a distinct delimiter is always given in string form.
155 Finally, the delimiter can be escaped if it is part of a key and also
156 has to be used as a delimiter. For example, ``foo[r".a.b\.c"]`` results in
157 a two element hierarchy of ``a`` and ``b.c``. For hard-coded strings it is
158 always better to use a different delimiter in these cases.
160 Note that adding a multi-level key implicitly creates any nesting levels
161 that do not exist, but removing multi-level keys does not automatically
162 remove empty nesting levels. As a result:
164 >>> c = Config()
165 >>> c[".a.b"] = 1
166 >>> del c[".a.b"]
167 >>> c["a"]
168 Config({'a': {}})
170 Storage formats supported:
172 - yaml: read and write is supported.
173 - json: read and write is supported but no ``!include`` directive.
175 Parameters
176 ----------
177 other : `str` or `Config` or `dict` or `ButlerURI` or `pathlib.Path`
178 Other source of configuration, can be:
180 - (`str` or `ButlerURI`) Treated as a URI to a config file. Must end
181 with ".yaml".
182 - (`Config`) Copies the other Config's values into this one.
183 - (`dict`) Copies the values from the dict into this Config.
185 If `None` is provided an empty `Config` will be created.
186 """
188 _D: str = "→"
189 """Default internal delimiter to use for components in the hierarchy when
190 constructing keys for external use (see `Config.names()`)."""
192 includeKey: ClassVar[str] = "includeConfigs"
193 """Key used to indicate that another config should be included at this
194 part of the hierarchy."""
196 resourcesPackage: str = "lsst.daf.butler"
197 """Package to search for default configuration data. The resources
198 themselves will be within a ``configs`` resource hierarchy."""
200 def __init__(self, other=None):
201 self._data: Dict[str, Any] = {}
202 self.configFile = None
204 if other is None:
205 return
207 if isinstance(other, Config):
208 self._data = copy.deepcopy(other._data)
209 self.configFile = other.configFile
210 elif isinstance(other, collections.abc.Mapping):
211 self.update(other)
212 elif isinstance(other, (str, ButlerURI, Path)): 212 ↛ 219line 212 didn't jump to line 219, because the condition on line 212 was never false
213 # if other is a string, assume it is a file path/URI
214 self.__initFromUri(other)
215 self._processExplicitIncludes()
216 else:
217 # if the config specified by other could not be recognized raise
218 # a runtime error.
219 raise RuntimeError(f"A Config could not be loaded from other: {other}")
221 def ppprint(self):
222 """Return config as formatted readable string.
224 Examples
225 --------
226 use: ``pdb> print(myConfigObject.ppprint())``
228 Returns
229 -------
230 s : `str`
231 A prettyprint formatted string representing the config
232 """
233 return pprint.pformat(self._data, indent=2, width=1)
235 def __repr__(self):
236 return f"{type(self).__name__}({self._data!r})"
238 def __str__(self):
239 return self.ppprint()
241 def __len__(self):
242 return len(self._data)
244 def __iter__(self):
245 return iter(self._data)
247 def copy(self):
248 return type(self)(self)
250 @classmethod
251 def fromString(cls, string: str, format: str = "yaml") -> Config:
252 """Create a new Config instance from a serialized string.
254 Parameters
255 ----------
256 string : `str`
257 String containing content in specified format
258 format : `str`, optional
259 Format of the supplied string. Can be ``json`` or ``yaml``.
261 Returns
262 -------
263 c : `Config`
264 Newly-constructed Config.
265 """
266 if format == "yaml":
267 new_config = cls().__initFromYaml(string)
268 elif format == "json":
269 new_config = cls().__initFromJson(string)
270 else:
271 raise ValueError(f"Unexpected format of string: {format}")
272 new_config._processExplicitIncludes()
273 return new_config
275 @classmethod
276 def fromYaml(cls, string: str) -> Config:
277 """Create a new Config instance from a YAML string.
279 Parameters
280 ----------
281 string : `str`
282 String containing content in YAML format
284 Returns
285 -------
286 c : `Config`
287 Newly-constructed Config.
288 """
289 return cls.fromString(string, format="yaml")
291 def __initFromUri(self, path: Union[str, ButlerURI, Path]) -> None:
292 """Load a file from a path or an URI.
294 Parameters
295 ----------
296 path : `str`
297 Path or a URI to a persisted config file.
298 """
299 uri = ButlerURI(path)
300 ext = uri.getExtension()
301 if ext == ".yaml": 301 ↛ 308line 301 didn't jump to line 308, because the condition on line 301 was never false
302 log.debug("Opening YAML config file: %s", uri.geturl())
303 content = uri.read()
304 # Use a stream so we can name it
305 stream = io.BytesIO(content)
306 stream.name = uri.geturl()
307 self.__initFromYaml(stream)
308 elif ext == ".json":
309 log.debug("Opening JSON config file: %s", uri.geturl())
310 content = uri.read()
311 self.__initFromJson(content)
312 else:
313 # This URI does not have a valid extension. It might be because
314 # we ended up with a directory and not a file. Before we complain
315 # about an extension, do an existence check. No need to do
316 # the (possibly expensive) existence check in the default code
317 # path above because we will find out soon enough that the file
318 # is not there.
319 if not uri.exists():
320 raise FileNotFoundError(f"Config location {uri} does not exist.")
321 raise RuntimeError(f"The Config URI does not have a supported extension: {uri}")
322 self.configFile = uri
324 def __initFromYaml(self, stream):
325 """Load a YAML config from any readable stream that contains one.
327 Parameters
328 ----------
329 stream: `IO` or `str`
330 Stream to pass to the YAML loader. Accepts anything that
331 `yaml.load` accepts. This can include a string as well as an
332 IO stream.
334 Raises
335 ------
336 yaml.YAMLError
337 If there is an error loading the file.
338 """
339 content = yaml.load(stream, Loader=Loader)
340 if content is None: 340 ↛ 341line 340 didn't jump to line 341, because the condition on line 340 was never true
341 content = {}
342 self._data = content
343 return self
345 def __initFromJson(self, stream):
346 """Load a JSON config from any readable stream that contains one.
348 Parameters
349 ----------
350 stream: `IO` or `str`
351 Stream to pass to the JSON loader. This can include a string as
352 well as an IO stream.
354 Raises
355 ------
356 TypeError:
357 Raised if there is an error loading the content.
358 """
359 if isinstance(stream, (bytes, str)):
360 content = json.loads(stream)
361 else:
362 content = json.load(stream)
363 if content is None:
364 content = {}
365 self._data = content
366 return self
368 def _processExplicitIncludes(self):
369 """Scan through the configuration searching for the special includes.
371 Looks for ``includeConfigs`` directive and processes the includes.
372 """
373 # Search paths for config files
374 searchPaths = [ButlerURI(os.path.curdir, forceDirectory=True)]
375 if self.configFile is not None: 375 ↛ 383line 375 didn't jump to line 383, because the condition on line 375 was never false
376 if isinstance(self.configFile, ButlerURI): 376 ↛ 379line 376 didn't jump to line 379, because the condition on line 376 was never false
377 configDir = self.configFile.dirname()
378 else:
379 raise RuntimeError(f"Unexpected type for config file: {self.configFile}")
380 searchPaths.append(configDir)
382 # Ensure we know what delimiter to use
383 names = self.nameTuples()
384 for path in names:
385 if path[-1] == self.includeKey: 385 ↛ 387line 385 didn't jump to line 387, because the condition on line 385 was never true
387 log.debug("Processing file include directive at %s", self._D + self._D.join(path))
388 basePath = path[:-1]
390 # Extract the includes and then delete them from the config
391 includes = self[path]
392 del self[path]
394 # Be consistent and convert to a list
395 if not isinstance(includes, list):
396 includes = [includes]
398 # Read each file assuming it is a reference to a file
399 # The file can be relative to config file or cwd
400 # ConfigSubset search paths are not used
401 subConfigs = []
402 for fileName in includes:
403 # Expand any shell variables -- this could be URI
404 fileName = ButlerURI(os.path.expandvars(fileName), forceAbsolute=False)
405 found = None
406 if fileName.isabs():
407 found = fileName
408 else:
409 for dir in searchPaths:
410 if isinstance(dir, ButlerURI):
411 specific = dir.join(fileName.path)
412 # Remote resource check might be expensive
413 if specific.exists():
414 found = specific
415 else:
416 log.warning("Do not understand search path entry '%s' of type %s",
417 dir, type(dir).__name__)
418 if not found:
419 raise RuntimeError(f"Unable to find referenced include file: {fileName}")
421 # Read the referenced Config as a Config
422 subConfigs.append(type(self)(found))
424 # Now we need to merge these sub configs with the current
425 # information that was present in this node in the config
426 # tree with precedence given to the explicit values
427 newConfig = subConfigs.pop(0)
428 for sc in subConfigs:
429 newConfig.update(sc)
431 # Explicit values take precedence
432 if not basePath:
433 # This is an include at the root config
434 newConfig.update(self)
435 # Replace the current config
436 self._data = newConfig._data
437 else:
438 newConfig.update(self[basePath])
439 # And reattach to the base config
440 self[basePath] = newConfig
442 @staticmethod
443 def _splitIntoKeys(key):
444 r"""Split the argument for get/set/in into a hierarchical list.
446 Parameters
447 ----------
448 key : `str` or iterable
449 Argument given to get/set/in. If an iterable is provided it will
450 be converted to a list. If the first character of the string
451 is not an alphanumeric character then it will be used as the
452 delimiter for the purposes of splitting the remainder of the
453 string. If the delimiter is also in one of the keys then it
454 can be escaped using ``\``. There is no default delimiter.
456 Returns
457 -------
458 keys : `list`
459 Hierarchical keys as a `list`.
460 """
461 if isinstance(key, str):
462 if not key[0].isalnum(): 462 ↛ 463line 462 didn't jump to line 463, because the condition on line 462 was never true
463 d = key[0]
464 key = key[1:]
465 else:
466 return [key, ]
467 escaped = f"\\{d}"
468 temp = None
469 if escaped in key:
470 # Complain at the attempt to escape the escape
471 doubled = fr"\{escaped}"
472 if doubled in key:
473 raise ValueError(f"Escaping an escaped delimiter ({doubled} in {key})"
474 " is not yet supported.")
475 # Replace with a character that won't be in the string
476 temp = "\r"
477 if temp in key or d == temp:
478 raise ValueError(f"Can not use character {temp!r} in hierarchical key or as"
479 " delimiter if escaping the delimiter")
480 key = key.replace(escaped, temp)
481 hierarchy = key.split(d)
482 if temp:
483 hierarchy = [h.replace(temp, d) for h in hierarchy]
484 return hierarchy
485 elif isinstance(key, collections.abc.Iterable): 485 ↛ 489line 485 didn't jump to line 489, because the condition on line 485 was never false
486 return list(key)
487 else:
488 # Not sure what this is so try it anyway
489 return [key, ]
491 def _getKeyHierarchy(self, name):
492 """Retrieve the key hierarchy for accessing the Config.
494 Parameters
495 ----------
496 name : `str` or `tuple`
497 Delimited string or `tuple` of hierarchical keys.
499 Returns
500 -------
501 hierarchy : `list` of `str`
502 Hierarchy to use as a `list`. If the name is available directly
503 as a key in the Config it will be used regardless of the presence
504 of any nominal delimiter.
505 """
506 if name in self._data:
507 keys = [name, ]
508 else:
509 keys = self._splitIntoKeys(name)
510 return keys
512 def _findInHierarchy(self, keys, create=False):
513 """Look for hierarchy of keys in Config.
515 Parameters
516 ----------
517 keys : `list` or `tuple`
518 Keys to search in hierarchy.
519 create : `bool`, optional
520 If `True`, if a part of the hierarchy does not exist, insert an
521 empty `dict` into the hierarchy.
523 Returns
524 -------
525 hierarchy : `list`
526 List of the value corresponding to each key in the supplied
527 hierarchy. Only keys that exist in the hierarchy will have
528 a value.
529 complete : `bool`
530 `True` if the full hierarchy exists and the final element
531 in ``hierarchy`` is the value of relevant value.
532 """
533 d = self._data
535 def checkNextItem(k, d, create):
536 """See if k is in d and if it is return the new child."""
537 nextVal = None
538 isThere = False
539 if d is None: 539 ↛ 541line 539 didn't jump to line 541, because the condition on line 539 was never true
540 # We have gone past the end of the hierarchy
541 pass
542 elif isinstance(d, collections.abc.Sequence): 542 ↛ 547line 542 didn't jump to line 547, because the condition on line 542 was never true
543 # Check sequence first because for lists
544 # __contains__ checks whether value is found in list
545 # not whether the index exists in list. When we traverse
546 # the hierarchy we are interested in the index.
547 try:
548 nextVal = d[int(k)]
549 isThere = True
550 except IndexError:
551 pass
552 except ValueError:
553 isThere = k in d
554 elif k in d:
555 nextVal = d[k]
556 isThere = True
557 elif create: 557 ↛ 558line 557 didn't jump to line 558, because the condition on line 557 was never true
558 d[k] = {}
559 nextVal = d[k]
560 isThere = True
561 return nextVal, isThere
563 hierarchy = []
564 complete = True
565 for k in keys:
566 d, isThere = checkNextItem(k, d, create)
567 if isThere:
568 hierarchy.append(d)
569 else:
570 complete = False
571 break
573 return hierarchy, complete
575 def __getitem__(self, name):
576 # Override the split for the simple case where there is an exact
577 # match. This allows `Config.items()` to work via a simple
578 # __iter__ implementation that returns top level keys of
579 # self._data.
580 keys = self._getKeyHierarchy(name)
582 hierarchy, complete = self._findInHierarchy(keys)
583 if not complete: 583 ↛ 584line 583 didn't jump to line 584, because the condition on line 583 was never true
584 raise KeyError(f"{name} not found")
585 data = hierarchy[-1]
587 if isinstance(data, collections.abc.Mapping):
588 data = Config(data)
589 # Ensure that child configs inherit the parent internal delimiter
590 if self._D != Config._D: 590 ↛ 591line 590 didn't jump to line 591, because the condition on line 590 was never true
591 data._D = self._D
592 return data
594 def __setitem__(self, name, value):
595 keys = self._getKeyHierarchy(name)
596 last = keys.pop()
597 if isinstance(value, Config):
598 value = copy.deepcopy(value._data)
600 hierarchy, complete = self._findInHierarchy(keys, create=True)
601 if hierarchy:
602 data = hierarchy[-1]
603 else:
604 data = self._data
606 try:
607 data[last] = value
608 except TypeError:
609 data[int(last)] = value
611 def __contains__(self, key):
612 keys = self._getKeyHierarchy(key)
613 hierarchy, complete = self._findInHierarchy(keys)
614 return complete
616 def __delitem__(self, key):
617 keys = self._getKeyHierarchy(key)
618 last = keys.pop()
619 hierarchy, complete = self._findInHierarchy(keys)
620 if complete: 620 ↛ 627line 620 didn't jump to line 627, because the condition on line 620 was never false
621 if hierarchy: 621 ↛ 622line 621 didn't jump to line 622, because the condition on line 621 was never true
622 data = hierarchy[-1]
623 else:
624 data = self._data
625 del data[last]
626 else:
627 raise KeyError(f"{key} not found in Config")
629 def update(self, other):
630 """Update config from other `Config` or `dict`.
632 Like `dict.update()`, but will add or modify keys in nested dicts,
633 instead of overwriting the nested dict entirely.
635 Parameters
636 ----------
637 other : `dict` or `Config`
638 Source of configuration:
640 Examples
641 --------
642 >>> c = Config({"a": {"b": 1}})
643 >>> c.update({"a": {"c": 2}})
644 >>> print(c)
645 {'a': {'b': 1, 'c': 2}}
647 >>> foo = {"a": {"b": 1}}
648 >>> foo.update({"a": {"c": 2}})
649 >>> print(foo)
650 {'a': {'c': 2}}
651 """
652 def doUpdate(d, u):
653 if not isinstance(u, collections.abc.Mapping) or \ 653 ↛ 655line 653 didn't jump to line 655, because the condition on line 653 was never true
654 not isinstance(d, collections.abc.MutableMapping):
655 raise RuntimeError("Only call update with Mapping, not {}".format(type(d)))
656 for k, v in u.items():
657 if isinstance(v, collections.abc.Mapping):
658 d[k] = doUpdate(d.get(k, {}), v)
659 else:
660 d[k] = v
661 return d
662 doUpdate(self._data, other)
664 def merge(self, other):
665 """Merge another Config into this one.
667 Like `Config.update()`, but will add keys & values from other that
668 DO NOT EXIST in self.
670 Keys and values that already exist in self will NOT be overwritten.
672 Parameters
673 ----------
674 other : `dict` or `Config`
675 Source of configuration:
676 """
677 if not isinstance(other, collections.abc.Mapping):
678 raise TypeError(f"Can only merge a Mapping into a Config, not {type(other)}")
680 # Convert the supplied mapping to a Config for consistency
681 # This will do a deepcopy if it is already a Config
682 otherCopy = Config(other)
683 otherCopy.update(self)
684 self._data = otherCopy._data
686 def nameTuples(self, topLevelOnly=False):
687 """Get tuples representing the name hierarchies of all keys.
689 The tuples returned from this method are guaranteed to be usable
690 to access items in the configuration object.
692 Parameters
693 ----------
694 topLevelOnly : `bool`, optional
695 If False, the default, a full hierarchy of names is returned.
696 If True, only the top level are returned.
698 Returns
699 -------
700 names : `list` of `tuple` of `str`
701 List of all names present in the `Config` where each element
702 in the list is a `tuple` of strings representing the hierarchy.
703 """
704 if topLevelOnly: 704 ↛ 705line 704 didn't jump to line 705, because the condition on line 704 was never true
705 return list((k,) for k in self)
707 def getKeysAsTuples(d, keys, base):
708 if isinstance(d, collections.abc.Sequence):
709 theseKeys = range(len(d))
710 else:
711 theseKeys = d.keys()
712 for key in theseKeys:
713 val = d[key]
714 levelKey = base + (key,) if base is not None else (key,)
715 keys.append(levelKey)
716 if isinstance(val, (collections.abc.Mapping, collections.abc.Sequence)) \
717 and not isinstance(val, str):
718 getKeysAsTuples(val, keys, levelKey)
719 keys: List[Tuple[str, ...]] = []
720 getKeysAsTuples(self._data, keys, None)
721 return keys
723 def names(self, topLevelOnly=False, delimiter=None):
724 """Get a delimited name of all the keys in the hierarchy.
726 The values returned from this method are guaranteed to be usable
727 to access items in the configuration object.
729 Parameters
730 ----------
731 topLevelOnly : `bool`, optional
732 If False, the default, a full hierarchy of names is returned.
733 If True, only the top level are returned.
734 delimiter : `str`, optional
735 Delimiter to use when forming the keys. If the delimiter is
736 present in any of the keys, it will be escaped in the returned
737 names. If `None` given a delimiter will be automatically provided.
738 The delimiter can not be alphanumeric.
740 Returns
741 -------
742 names : `list` of `str`
743 List of all names present in the `Config`.
745 Notes
746 -----
747 This is different than the built-in method `dict.keys`, which will
748 return only the first level keys.
750 Raises
751 ------
752 ValueError:
753 The supplied delimiter is alphanumeric.
754 """
755 if topLevelOnly:
756 return list(self.keys())
758 # Get all the tuples of hierarchical keys
759 nameTuples = self.nameTuples()
761 if delimiter is not None and delimiter.isalnum():
762 raise ValueError(f"Supplied delimiter ({delimiter!r}) must not be alphanumeric.")
764 if delimiter is None:
765 # Start with something, and ensure it does not need to be
766 # escaped (it is much easier to understand if not escaped)
767 delimiter = self._D
769 # Form big string for easy check of delimiter clash
770 combined = "".join("".join(str(s) for s in k) for k in nameTuples)
772 # Try a delimiter and keep trying until we get something that
773 # works.
774 ntries = 0
775 while delimiter in combined:
776 log.debug("Delimiter '%s' could not be used. Trying another.", delimiter)
777 ntries += 1
779 if ntries > 100:
780 raise ValueError(f"Unable to determine a delimiter for Config {self}")
782 # try another one
783 while True:
784 delimiter = chr(ord(delimiter)+1)
785 if not delimiter.isalnum():
786 break
788 log.debug("Using delimiter %r", delimiter)
790 # Form the keys, escaping the delimiter if necessary
791 strings = [delimiter + delimiter.join(str(s).replace(delimiter, f"\\{delimiter}") for s in k)
792 for k in nameTuples]
793 return strings
795 def asArray(self, name):
796 """Get a value as an array.
798 May contain one or more elements.
800 Parameters
801 ----------
802 name : `str`
803 Key to use to retrieve value.
805 Returns
806 -------
807 array : `collections.abc.Sequence`
808 The value corresponding to name, but guaranteed to be returned
809 as a list with at least one element. If the value is a
810 `~collections.abc.Sequence` (and not a `str`) the value itself
811 will be returned, else the value will be the first element.
812 """
813 val = self.get(name)
814 if isinstance(val, str):
815 val = [val]
816 elif not isinstance(val, collections.abc.Sequence):
817 val = [val]
818 return val
820 def __eq__(self, other):
821 if isinstance(other, Config):
822 other = other._data
823 return self._data == other
825 def __ne__(self, other):
826 if isinstance(other, Config):
827 other = other._data
828 return self._data != other
830 #######
831 # i/o #
833 def dump(self, output: Optional[IO] = None, format: str = "yaml") -> Optional[str]:
834 """Write the config to an output stream.
836 Parameters
837 ----------
838 output : `IO`, optional
839 The stream to use for output. If `None` the serialized content
840 will be returned.
841 format : `str`, optional
842 The format to use for the output. Can be "yaml" or "json".
844 Returns
845 -------
846 serialized : `str` or `None`
847 If a stream was given the stream will be used and the return
848 value will be `None`. If the stream was `None` the
849 serialization will be returned as a string.
850 """
851 if format == "yaml":
852 return yaml.safe_dump(self._data, output, default_flow_style=False)
853 elif format == "json":
854 if output is not None:
855 json.dump(self._data, output, ensure_ascii=False)
856 return None
857 else:
858 return json.dumps(self._data, ensure_ascii=False)
859 raise ValueError(f"Unsupported format for Config serialization: {format}")
861 def dumpToUri(self, uri: Union[ButlerURI, str], updateFile: bool = True,
862 defaultFileName: str = "butler.yaml",
863 overwrite: bool = True) -> None:
864 """Write the config to location pointed to by given URI.
866 Currently supports 's3' and 'file' URI schemes.
868 Parameters
869 ----------
870 uri: `str` or `ButlerURI`
871 URI of location where the Config will be written.
872 updateFile : bool, optional
873 If True and uri does not end on a filename with extension, will
874 append `defaultFileName` to the target uri. True by default.
875 defaultFileName : bool, optional
876 The file name that will be appended to target uri if updateFile is
877 True and uri does not end on a file with an extension.
878 overwrite : bool, optional
879 If True the configuration will be written even if it already
880 exists at that location.
881 """
882 # Make local copy of URI or create new one
883 uri = ButlerURI(uri)
885 if updateFile and not uri.getExtension():
886 uri = uri.updatedFile(defaultFileName)
888 # Try to work out the format from the extension
889 ext = uri.getExtension()
890 format = ext[1:].lower()
892 output = self.dump(format=format)
893 assert output is not None, "Config.dump guarantees not-None return when output arg is None"
894 uri.write(output.encode(), overwrite=overwrite)
895 self.configFile = uri
897 @staticmethod
898 def updateParameters(configType, config, full, toUpdate=None, toCopy=None, overwrite=True, toMerge=None):
899 """Update specific config parameters.
901 Allows for named parameters to be set to new values in bulk, and
902 for other values to be set by copying from a reference config.
904 Assumes that the supplied config is compatible with ``configType``
905 and will attach the updated values to the supplied config by
906 looking for the related component key. It is assumed that
907 ``config`` and ``full`` are from the same part of the
908 configuration hierarchy.
910 Parameters
911 ----------
912 configType : `ConfigSubset`
913 Config type to use to extract relevant items from ``config``.
914 config : `Config`
915 A `Config` to update. Only the subset understood by
916 the supplied `ConfigSubset` will be modified. Default values
917 will not be inserted and the content will not be validated
918 since mandatory keys are allowed to be missing until
919 populated later by merging.
920 full : `Config`
921 A complete config with all defaults expanded that can be
922 converted to a ``configType``. Read-only and will not be
923 modified by this method. Values are read from here if
924 ``toCopy`` is defined.
926 Repository-specific options that should not be obtained
927 from defaults when Butler instances are constructed
928 should be copied from ``full`` to ``config``.
929 toUpdate : `dict`, optional
930 A `dict` defining the keys to update and the new value to use.
931 The keys and values can be any supported by `Config`
932 assignment.
933 toCopy : `tuple`, optional
934 `tuple` of keys whose values should be copied from ``full``
935 into ``config``.
936 overwrite : `bool`, optional
937 If `False`, do not modify a value in ``config`` if the key
938 already exists. Default is always to overwrite.
939 toMerge : `tuple`, optional
940 Keys to merge content from full to config without overwriting
941 pre-existing values. Only works if the key refers to a hierarchy.
942 The ``overwrite`` flag is ignored.
944 Raises
945 ------
946 ValueError
947 Neither ``toUpdate``, ``toCopy`` nor ``toMerge`` were defined.
948 """
949 if toUpdate is None and toCopy is None and toMerge is None:
950 raise ValueError("At least one of toUpdate, toCopy, or toMerge parameters must be set.")
952 # If this is a parent configuration then we need to ensure that
953 # the supplied config has the relevant component key in it.
954 # If this is a parent configuration we add in the stub entry
955 # so that the ConfigSubset constructor will do the right thing.
956 # We check full for this since that is guaranteed to be complete.
957 if configType.component in full and configType.component not in config:
958 config[configType.component] = {}
960 # Extract the part of the config we wish to update
961 localConfig = configType(config, mergeDefaults=False, validate=False)
963 if toUpdate:
964 for key, value in toUpdate.items():
965 if key in localConfig and not overwrite:
966 log.debug("Not overriding key '%s' with value '%s' in config %s",
967 key, value, localConfig.__class__.__name__)
968 else:
969 localConfig[key] = value
971 if toCopy or toMerge:
972 localFullConfig = configType(full, mergeDefaults=False)
974 if toCopy:
975 for key in toCopy:
976 if key in localConfig and not overwrite:
977 log.debug("Not overriding key '%s' from defaults in config %s",
978 key, localConfig.__class__.__name__)
979 else:
980 localConfig[key] = localFullConfig[key]
981 if toMerge:
982 for key in toMerge:
983 if key in localConfig:
984 # Get the node from the config to do the merge
985 # but then have to reattach to the config.
986 subset = localConfig[key]
987 subset.merge(localFullConfig[key])
988 localConfig[key] = subset
989 else:
990 localConfig[key] = localFullConfig[key]
992 # Reattach to parent if this is a child config
993 if configType.component in config:
994 config[configType.component] = localConfig
995 else:
996 config.update(localConfig)
998 def toDict(self):
999 """Convert a `Config` to a standalone hierarchical `dict`.
1001 Returns
1002 -------
1003 d : `dict`
1004 The standalone hierarchical `dict` with any `Config` classes
1005 in the hierarchy converted to `dict`.
1007 Notes
1008 -----
1009 This can be useful when passing a Config to some code that
1010 expects native Python types.
1011 """
1012 output = copy.deepcopy(self._data)
1013 for k, v in output.items():
1014 if isinstance(v, Config):
1015 v = v.toDict()
1016 output[k] = v
1017 return output
1020class ConfigSubset(Config):
1021 """Config representing a subset of a more general configuration.
1023 Subclasses define their own component and when given a configuration
1024 that includes that component, the resulting configuration only includes
1025 the subset. For example, your config might contain ``dimensions`` if it's
1026 part of a global config and that subset will be stored. If ``dimensions``
1027 can not be found it is assumed that the entire contents of the
1028 configuration should be used.
1030 Default values are read from the environment or supplied search paths
1031 using the default configuration file name specified in the subclass.
1032 This allows a configuration class to be instantiated without any
1033 additional arguments.
1035 Additional validation can be specified to check for keys that are mandatory
1036 in the configuration.
1038 Parameters
1039 ----------
1040 other : `Config` or `str` or `dict`
1041 Argument specifying the configuration information as understood
1042 by `Config`
1043 validate : `bool`, optional
1044 If `True` required keys will be checked to ensure configuration
1045 consistency.
1046 mergeDefaults : `bool`, optional
1047 If `True` defaults will be read and the supplied config will
1048 be combined with the defaults, with the supplied valiues taking
1049 precedence.
1050 searchPaths : `list` or `tuple`, optional
1051 Explicit additional paths to search for defaults. They should
1052 be supplied in priority order. These paths have higher priority
1053 than those read from the environment in
1054 `ConfigSubset.defaultSearchPaths()`. Paths can be `str` referring to
1055 the local file system or URIs, `ButlerURI`.
1056 """
1058 component: ClassVar[Optional[str]] = None
1059 """Component to use from supplied config. Can be None. If specified the
1060 key is not required. Can be a full dot-separated path to a component.
1061 """
1063 requiredKeys: ClassVar[Sequence[str]] = ()
1064 """Keys that are required to be specified in the configuration.
1065 """
1067 defaultConfigFile: ClassVar[Optional[str]] = None
1068 """Name of the file containing defaults for this config class.
1069 """
1071 def __init__(self, other=None, validate=True, mergeDefaults=True, searchPaths=None):
1073 # Create a blank object to receive the defaults
1074 # Once we have the defaults we then update with the external values
1075 super().__init__()
1077 # Create a standard Config rather than subset
1078 externalConfig = Config(other)
1080 # Select the part we need from it
1081 # To simplify the use of !include we also check for the existence of
1082 # component.component (since the included files can themselves
1083 # include the component name)
1084 if self.component is not None: 1084 ↛ 1093line 1084 didn't jump to line 1093, because the condition on line 1084 was never false
1085 doubled = (self.component, self.component)
1086 # Must check for double depth first
1087 if doubled in externalConfig: 1087 ↛ 1088line 1087 didn't jump to line 1088, because the condition on line 1087 was never true
1088 externalConfig = externalConfig[doubled]
1089 elif self.component in externalConfig:
1090 externalConfig._data = externalConfig._data[self.component]
1092 # Default files read to create this configuration
1093 self.filesRead = []
1095 # Assume we are not looking up child configurations
1096 containerKey = None
1098 # Sometimes we do not want to merge with defaults.
1099 if mergeDefaults:
1101 # Supplied search paths have highest priority
1102 fullSearchPath = []
1103 if searchPaths: 1103 ↛ 1104line 1103 didn't jump to line 1104, because the condition on line 1103 was never true
1104 fullSearchPath.extend(searchPaths)
1106 # Read default paths from enviroment
1107 fullSearchPath.extend(self.defaultSearchPaths())
1109 # There are two places to find defaults for this particular config
1110 # - The "defaultConfigFile" defined in the subclass
1111 # - The class specified in the "cls" element in the config.
1112 # Read cls after merging in case it changes.
1113 if self.defaultConfigFile is not None: 1113 ↛ 1118line 1113 didn't jump to line 1118, because the condition on line 1113 was never false
1114 self._updateWithConfigsFromPath(fullSearchPath, self.defaultConfigFile)
1116 # Can have a class specification in the external config (priority)
1117 # or from the defaults.
1118 pytype = None
1119 if "cls" in externalConfig: 1119 ↛ 1120line 1119 didn't jump to line 1120, because the condition on line 1119 was never true
1120 pytype = externalConfig["cls"]
1121 elif "cls" in self: 1121 ↛ 1122line 1121 didn't jump to line 1122, because the condition on line 1121 was never true
1122 pytype = self["cls"]
1124 if pytype is not None: 1124 ↛ 1125line 1124 didn't jump to line 1125, because the condition on line 1124 was never true
1125 try:
1126 cls = doImport(pytype)
1127 except ImportError as e:
1128 raise RuntimeError(f"Failed to import cls '{pytype}' for config {type(self)}") from e
1129 defaultsFile = cls.defaultConfigFile
1130 if defaultsFile is not None:
1131 self._updateWithConfigsFromPath(fullSearchPath, defaultsFile)
1133 # Get the container key in case we need it
1134 try:
1135 containerKey = cls.containerKey
1136 except AttributeError:
1137 pass
1139 # Now update this object with the external values so that the external
1140 # values always override the defaults
1141 self.update(externalConfig)
1143 # If this configuration has child configurations of the same
1144 # config class, we need to expand those defaults as well.
1146 if mergeDefaults and containerKey is not None and containerKey in self: 1146 ↛ 1147line 1146 didn't jump to line 1147, because the condition on line 1146 was never true
1147 for idx, subConfig in enumerate(self[containerKey]):
1148 self[containerKey, idx] = type(self)(other=subConfig, validate=validate,
1149 mergeDefaults=mergeDefaults,
1150 searchPaths=searchPaths)
1152 if validate:
1153 self.validate()
1155 @classmethod
1156 def defaultSearchPaths(cls):
1157 """Read environment to determine search paths to use.
1159 Global defaults, at lowest priority, are found in the ``config``
1160 directory of the butler source tree. Additional defaults can be
1161 defined using the environment variable ``$DAF_BUTLER_CONFIG_PATHS``
1162 which is a PATH-like variable where paths at the front of the list
1163 have priority over those later.
1165 Returns
1166 -------
1167 paths : `list`
1168 Returns a list of paths to search. The returned order is in
1169 priority with the highest priority paths first. The butler config
1170 configuration resources will not be included here but will
1171 always be searched last.
1173 Notes
1174 -----
1175 The environment variable is split on the standard ``:`` path separator.
1176 This currently makes it incompatible with usage of URIs.
1177 """
1178 # We can pick up defaults from multiple search paths
1179 # We fill defaults by using the butler config path and then
1180 # the config path environment variable in reverse order.
1181 defaultsPaths: List[Union[str, ButlerURI]] = []
1183 if CONFIG_PATH in os.environ: 1183 ↛ 1184line 1183 didn't jump to line 1184, because the condition on line 1183 was never true
1184 externalPaths = os.environ[CONFIG_PATH].split(os.pathsep)
1185 defaultsPaths.extend(externalPaths)
1187 # Add the package defaults as a resource
1188 defaultsPaths.append(ButlerURI(f"resource://{cls.resourcesPackage}/configs",
1189 forceDirectory=True))
1190 return defaultsPaths
1192 def _updateWithConfigsFromPath(self, searchPaths, configFile):
1193 """Search the supplied paths, merging the configuration values.
1195 The values read will override values currently stored in the object.
1196 Every file found in the path will be read, such that the earlier
1197 path entries have higher priority.
1199 Parameters
1200 ----------
1201 searchPaths : `list` of `ButlerURI`, `str`
1202 Paths to search for the supplied configFile. This path
1203 is the priority order, such that files read from the
1204 first path entry will be selected over those read from
1205 a later path. Can contain `str` referring to the local file
1206 system or a URI string.
1207 configFile : `ButlerURI`
1208 File to locate in path. If absolute path it will be read
1209 directly and the search path will not be used. Can be a URI
1210 to an explicit resource (which will ignore the search path)
1211 which is assumed to exist.
1212 """
1213 uri = ButlerURI(configFile)
1214 if uri.isabs() and uri.exists(): 1214 ↛ 1216line 1214 didn't jump to line 1216, because the condition on line 1214 was never true
1215 # Assume this resource exists
1216 self._updateWithOtherConfigFile(configFile)
1217 self.filesRead.append(configFile)
1218 else:
1219 # Reverse order so that high priority entries
1220 # update the object last.
1221 for pathDir in reversed(searchPaths):
1222 if isinstance(pathDir, (str, ButlerURI)): 1222 ↛ 1229line 1222 didn't jump to line 1229, because the condition on line 1222 was never false
1223 pathDir = ButlerURI(pathDir, forceDirectory=True)
1224 file = pathDir.join(configFile)
1225 if file.exists(): 1225 ↛ 1221line 1225 didn't jump to line 1221, because the condition on line 1225 was never false
1226 self.filesRead.append(file)
1227 self._updateWithOtherConfigFile(file)
1228 else:
1229 raise ValueError(f"Unexpected search path type encountered: {pathDir!r}")
1231 def _updateWithOtherConfigFile(self, file):
1232 """Read in some defaults and update.
1234 Update the configuration by reading the supplied file as a config
1235 of this class, and merging such that these values override the
1236 current values. Contents of the external config are not validated.
1238 Parameters
1239 ----------
1240 file : `Config`, `str`, `ButlerURI`, or `dict`
1241 Entity that can be converted to a `ConfigSubset`.
1242 """
1243 # Use this class to read the defaults so that subsetting can happen
1244 # correctly.
1245 externalConfig = type(self)(file, validate=False, mergeDefaults=False)
1246 self.update(externalConfig)
1248 def validate(self):
1249 """Check that mandatory keys are present in this configuration.
1251 Ignored if ``requiredKeys`` is empty.
1252 """
1253 # Validation
1254 missing = [k for k in self.requiredKeys if k not in self._data]
1255 if missing: 1255 ↛ 1256line 1255 didn't jump to line 1256, because the condition on line 1255 was never true
1256 raise KeyError(f"Mandatory keys ({missing}) missing from supplied configuration for {type(self)}")