Coverage for python/astro_metadata_translator/observationGroup.py: 29%
76 statements
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« prev ^ index » next coverage.py v7.2.7, created at 2023-07-12 11:01 -0700
1# This file is part of astro_metadata_translator.
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 LICENSE file at the top-level directory of this distribution
7# for details of code ownership.
8#
9# Use of this source code is governed by a 3-clause BSD-style
10# license that can be found in the LICENSE file.
12"""Represent a collection of translated headers."""
14from __future__ import annotations
16__all__ = ("ObservationGroup",)
18import logging
19from collections.abc import Callable, Iterable, Iterator, MutableMapping, MutableSequence
20from typing import TYPE_CHECKING, Any
22from .observationInfo import ObservationInfo
24if TYPE_CHECKING: 24 ↛ 25line 24 didn't jump to line 25, because the condition on line 24 was never true
25 from .translator import MetadataTranslator
27log = logging.getLogger(__name__)
30class ObservationGroup(MutableSequence):
31 """A collection of `ObservationInfo` headers.
33 Parameters
34 ----------
35 members : iterable of `ObservationInfo` or `dict`-like
36 `ObservationInfo` to seed the group membership. If `dict`-like
37 values are used they will be passed to the `ObservationInfo`
38 constructor.
39 translator_class : `MetadataTranslator`-class, optional
40 If any of the members is not an `ObservationInfo`, translator class
41 to pass to the `ObservationInfo` constructor. If `None` the
42 translation class will be determined automatically.
43 pedantic : `bool`, optional
44 If any of the members is not an `ObservationInfo`, passed to the
45 `ObservationInfo` constructor to control whether
46 a failed translation is fatal or not. `None` indicates that the
47 `ObservationInfo` constructor default should be used.
48 """
50 def __init__(
51 self,
52 members: Iterable[ObservationInfo | MutableMapping[str, Any]],
53 translator_class: type[MetadataTranslator] | None = None,
54 pedantic: bool | None = None,
55 ) -> None:
56 self._members = [
57 self._coerce_value(m, translator_class=translator_class, pedantic=pedantic) for m in members
58 ]
60 # Cache of members in time order
61 self._sorted: list[ObservationInfo] | None = None
63 def __len__(self) -> int:
64 return len(self._members)
66 def __delitem__(self, index: int) -> None: # type: ignore
67 del self._members[index]
68 self._sorted = None
70 def __getitem__(self, index: int) -> ObservationInfo: # type: ignore
71 return self._members[index]
73 def __str__(self) -> str:
74 results = []
75 for obs_info in self._members:
76 results.append(f"({obs_info.instrument}, {obs_info.datetime_begin})")
77 return "[" + ", ".join(results) + "]"
79 def _coerce_value(
80 self,
81 value: ObservationInfo | MutableMapping[str, Any],
82 translator_class: type[MetadataTranslator] | None = None,
83 pedantic: bool | None = None,
84 ) -> ObservationInfo:
85 """Given a value, ensure it is an `ObservationInfo`.
87 Parameters
88 ----------
89 value : `ObservationInfo` or `dict`-like
90 Either an `ObservationInfo` or something that can be passed to
91 an `ObservationInfo` constructor.
92 translator_class : `MetadataTranslator`-class, optional
93 If value is not an `ObservationInfo`, translator class to pass to
94 the `ObservationInfo` constructor. If `None` the
95 translation class will be determined automatically.
96 pedantic : `bool`, optional
97 If value is not an `ObservationInfo`, passed to the
98 `ObservationInfo` constructor to control whether
99 a failed translation is fatal or not. `None` indicates that the
100 `ObservationInfo` constructor default should be used.
102 Raises
103 ------
104 ValueError
105 Raised if supplied value is not an `ObservationInfo` and can
106 not be turned into one.
107 """
108 if value is None:
109 raise ValueError("An ObservationGroup cannot contain 'None'")
111 if not isinstance(value, ObservationInfo):
112 try:
113 kwargs: dict[str, Any] = {"translator_class": translator_class}
114 if pedantic is not None:
115 kwargs["pedantic"] = pedantic
116 value = ObservationInfo(value, **kwargs)
117 except Exception as e:
118 raise ValueError("Could not convert value to ObservationInfo") from e
120 return value
122 def __iter__(self) -> Iterator[ObservationInfo]:
123 return iter(self._members)
125 def __eq__(self, other: Any) -> bool:
126 """Check equality with another group.
128 Compare equal if all the members are equal in the same order.
129 """
130 if not isinstance(other, ObservationGroup):
131 return NotImplemented
133 for info1, info2 in zip(self, other):
134 if info1 != info2:
135 return False
136 return True
138 def __setitem__( # type: ignore
139 self, index: int, value: ObservationInfo | MutableMapping[str, Any]
140 ) -> None:
141 """Store item in group.
143 Item must be an `ObservationInfo` or something that can be passed
144 to an `ObservationInfo` constructor.
145 """
146 value = self._coerce_value(value)
147 self._members[index] = value
148 self._sorted = None
150 def insert(self, index: int, value: ObservationInfo | MutableMapping[str, Any]) -> None:
151 value = self._coerce_value(value)
152 self._members.insert(index, value)
153 self._sorted = None
155 def reverse(self) -> None:
156 self._members.reverse()
158 def sort(self, key: Callable | None = None, reverse: bool = False) -> None:
159 self._members.sort(key=key, reverse=reverse)
160 if key is None and not reverse and self._sorted is None:
161 # Store sorted order in cache
162 self._sorted = self._members.copy()
164 def extremes(self) -> tuple[ObservationInfo, ObservationInfo]:
165 """Return the oldest observation in the group and the newest.
167 If there is only one member of the group, the newest and oldest
168 can be the same observation.
170 Returns
171 -------
172 oldest : `ObservationInfo`
173 Oldest observation.
174 newest : `ObservationInfo`
175 Newest observation.
176 """
177 if self._sorted is None:
178 self._sorted = sorted(self._members)
179 return self._sorted[0], self._sorted[-1]
181 def newest(self) -> ObservationInfo:
182 """Return the newest observation in the group.
184 Returns
185 -------
186 newest : `ObservationInfo`
187 The newest `ObservationInfo` in the `ObservationGroup`.
188 """
189 return self.extremes()[1]
191 def oldest(self) -> ObservationInfo:
192 """Return the oldest observation in the group.
194 Returns
195 -------
196 oldest : `ObservationInfo`
197 The oldest `ObservationInfo` in the `ObservationGroup`.
198 """
199 return self.extremes()[0]
201 def property_values(self, property: str) -> set[Any]:
202 """Return a set of values associated with the specified property.
204 Parameters
205 ----------
206 property : `str`
207 Property of an `ObservationInfo`
209 Returns
210 -------
211 values : `set`
212 All the distinct values for that property within this group.
213 """
214 return {getattr(obs_info, property) for obs_info in self}
216 def to_simple(self) -> list[MutableMapping[str, Any]]:
217 """Convert the group to simplified form.
219 Returns
220 -------
221 simple : `list` of `dict`
222 Simple form is a list containing the simplified dict form of
223 each `ObservationInfo`.
224 """
225 return [obsinfo.to_simple() for obsinfo in self]
227 @classmethod
228 def from_simple(cls, simple: list[dict[str, Any]]) -> ObservationGroup:
229 """Convert simplified form back to `ObservationGroup`.
231 Parameters
232 ----------
233 simple : `list` of `dict`
234 Object returned by `to_simple`.
236 Returns
237 -------
238 group : `ObservationGroup`
239 Reconstructed group.
240 """
241 return cls(ObservationInfo.from_simple(o) for o in simple)