Coverage for python/lsst/images/json/_output_archive.py: 57%
55 statements
« prev ^ index » next coverage.py v7.15.2, created at 2026-07-25 09:03 +0000
« prev ^ index » next coverage.py v7.15.2, created at 2026-07-25 09:03 +0000
1# This file is part of lsst-images.
2#
3# Developed for the LSST Data Management System.
4# This product includes software developed by the LSST Project
5# (https://www.lsst.org).
6# See the COPYRIGHT 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.
12from __future__ import annotations
14__all__ = ("JsonOutputArchive", "write")
16from collections.abc import Callable, Hashable, Iterator, Mapping
17from typing import TYPE_CHECKING, Any
19import astropy.table
20import numpy as np
21import pydantic
23from lsst.resources import ResourcePath, ResourcePathExpression
25from .._transforms import FrameSet
26from ..serialization import (
27 ArchiveTree,
28 ButlerInfo,
29 InlineArrayModel,
30 JsonRef,
31 MetadataValue,
32 NestedOutputArchive,
33 NumberType,
34 OutputArchive,
35 TableColumnModel,
36 TableModel,
37 no_header_updates,
38)
40if TYPE_CHECKING:
41 import astropy.io.fits
44def write(
45 obj: Any,
46 path: ResourcePathExpression | None = None,
47 metadata: dict[str, MetadataValue] | None = None,
48 butler_info: ButlerInfo | None = None,
49) -> ArchiveTree:
50 """Write an object with a ``serialize`` method to a JSON file.
52 Parameters
53 ----------
54 obj
55 Object with a ``serialize`` method to write.
56 path
57 Name of the file to write to (may be a URI). If not provided, a
58 serializable model is returned but not written to disk.
59 metadata
60 Additional metadata to save with the object. This will override any
61 flexible metadata carried by the object itself with the same keys.
62 butler_info
63 Butler information to store in the file.
65 Returns
66 -------
67 `.serialization.ArchiveTree`
68 The serialized representation of the object.
69 """
70 archive = JsonOutputArchive()
71 tree = archive.serialize_root(obj, metadata, butler_info)
72 archive.finish(tree)
73 if path is not None: 73 ↛ 75line 73 didn't jump to line 75 because the condition on line 73 was always true
74 ResourcePath(path).write(tree.model_dump_json().encode())
75 return tree
78class JsonOutputArchive(OutputArchive[JsonRef]):
79 """An implementation of the `.serialization.OutputArchive` interface that
80 writes to JSON files.
82 This archive type is designed for pure-JSON objects and cases where any
83 images or tables are tiny. It will be *extremely* inefficient for large
84 images or tables, if it works at all.
85 """
87 def __init__(self) -> None:
88 super().__init__()
89 self._pointers: dict[Hashable, JsonRef] = {}
90 self._indirect: list[Any] = []
91 self._frame_sets: list[tuple[FrameSet, JsonRef]] = []
93 def serialize_direct[T: pydantic.BaseModel | None](
94 self, name: str, serializer: Callable[[OutputArchive[JsonRef]], T]
95 ) -> T:
96 nested = NestedOutputArchive[JsonRef](name, self)
97 return serializer(nested)
99 def serialize_pointer[T: ArchiveTree](
100 self, name: str, serializer: Callable[[OutputArchive[JsonRef]], T], key: Hashable
101 ) -> JsonRef:
102 if (pointer := self._pointers.get(key)) is not None:
103 return pointer
104 pointer = JsonRef.model_construct(ref=f"#/indirect/{len(self._indirect)}")
105 self._indirect.append(self.serialize_direct(name, serializer).model_dump())
106 self._pointers[key] = pointer
107 return pointer
109 def serialize_frame_set[T: ArchiveTree](
110 self, name: str, frame_set: FrameSet, serializer: Callable[[OutputArchive], T], key: Hashable
111 ) -> JsonRef:
112 pointer = self.serialize_pointer(name, serializer, key)
113 self._frame_sets.append((frame_set, pointer))
114 return pointer
116 def iter_frame_sets(self) -> Iterator[tuple[FrameSet, JsonRef]]:
117 return iter(self._frame_sets)
119 def add_array(
120 self,
121 array: np.ndarray,
122 *,
123 name: str | None = None,
124 update_header: Callable[[astropy.io.fits.Header], None] = no_header_updates,
125 tile_shape: tuple[int, ...] | None = None,
126 options_name: str | None = None,
127 ) -> InlineArrayModel:
128 return InlineArrayModel(
129 data=array.tolist(),
130 datatype=NumberType.from_numpy(array.dtype),
131 )
133 def add_table(
134 self,
135 table: astropy.table.Table,
136 *,
137 name: str | None = None,
138 update_header: Callable[[astropy.io.fits.Header], None] = no_header_updates,
139 ) -> TableModel:
140 columns = TableColumnModel.from_table(table, inline=True)
141 return TableModel(columns=columns, meta=table.meta)
143 def add_structured_array(
144 self,
145 array: np.ndarray,
146 *,
147 name: str | None = None,
148 units: Mapping[str, astropy.units.Unit] | None = None,
149 descriptions: Mapping[str, str] | None = None,
150 update_header: Callable[[astropy.io.fits.Header], None] = no_header_updates,
151 ) -> TableModel:
152 columns = TableColumnModel.from_record_array(array, inline=True)
153 for c in columns:
154 if units and (unit := units.get(c.name)):
155 c.unit = unit
156 if descriptions and (description := descriptions.get(c.name)):
157 c.description = description
158 return TableModel(columns=columns)
160 def finish[T: ArchiveTree](self, tree: T) -> T:
161 """Finish serialization.
163 Parameters
164 ----------
165 tree
166 Serialized archive tree to write, which is modified in place
167 (the ``indirect`` attribute is overwritten) and then returned.
168 """
169 tree.indirect = self._indirect
170 return tree