Coverage for python/lsst/daf/butler/registry/attributes.py: 37%

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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/>. 

21 

22"""The default concrete implementation of the class that manages 

23attributes for `Registry`. 

24""" 

25 

26from __future__ import annotations 

27 

28__all__ = ["DefaultButlerAttributeManager"] 

29 

30from collections.abc import Iterable 

31from typing import ClassVar 

32 

33import sqlalchemy 

34 

35from ..core.ddl import FieldSpec, TableSpec 

36from .interfaces import ( 

37 ButlerAttributeExistsError, 

38 ButlerAttributeManager, 

39 Database, 

40 StaticTablesContext, 

41 VersionTuple, 

42) 

43 

44# Schema version 1.0.1 signifies that we do not write schema digests. Writing 

45# is done by the `versions` module, but table is controlled by this manager. 

46_VERSION = VersionTuple(1, 0, 1) 

47 

48 

49class DefaultButlerAttributeManager(ButlerAttributeManager): 

50 """An implementation of `ButlerAttributeManager` that stores attributes 

51 in a database table. 

52 

53 Parameters 

54 ---------- 

55 db : `Database` 

56 Database engine interface for the namespace in which this table lives. 

57 table : `sqlalchemy.schema.Table` 

58 SQLAlchemy representation of the table that stores attributes. 

59 """ 

60 

61 def __init__( 

62 self, 

63 db: Database, 

64 table: sqlalchemy.schema.Table, 

65 registry_schema_version: VersionTuple | None = None, 

66 ): 

67 super().__init__(registry_schema_version=registry_schema_version) 

68 self._db = db 

69 self._table = table 

70 

71 _TABLE_NAME: ClassVar[str] = "butler_attributes" 

72 

73 _TABLE_SPEC: ClassVar[TableSpec] = TableSpec( 

74 fields=[ 

75 FieldSpec("name", dtype=sqlalchemy.String, length=1024, primaryKey=True), 

76 FieldSpec("value", dtype=sqlalchemy.String, length=65535, nullable=False), 

77 ], 

78 ) 

79 

80 @classmethod 

81 def initialize( 

82 cls, db: Database, context: StaticTablesContext, registry_schema_version: VersionTuple | None = None 

83 ) -> ButlerAttributeManager: 

84 # Docstring inherited from ButlerAttributeManager. 

85 table = context.addTable(cls._TABLE_NAME, cls._TABLE_SPEC) 

86 return cls(db=db, table=table, registry_schema_version=registry_schema_version) 

87 

88 def get(self, name: str, default: str | None = None) -> str | None: 

89 # Docstring inherited from ButlerAttributeManager. 

90 sql = sqlalchemy.sql.select(self._table.columns.value).where(self._table.columns.name == name) 

91 with self._db.query(sql) as sql_result: 

92 row = sql_result.fetchone() 

93 if row is not None: 

94 return row[0] 

95 return default 

96 

97 def set(self, name: str, value: str, *, force: bool = False) -> None: 

98 # Docstring inherited from ButlerAttributeManager. 

99 if not name or not value: 

100 raise ValueError("name and value cannot be empty") 

101 if force: 

102 self._db.replace( 

103 self._table, 

104 { 

105 "name": name, 

106 "value": value, 

107 }, 

108 ) 

109 else: 

110 try: 

111 self._db.insert( 

112 self._table, 

113 { 

114 "name": name, 

115 "value": value, 

116 }, 

117 ) 

118 except sqlalchemy.exc.IntegrityError as exc: 

119 raise ButlerAttributeExistsError(f"attribute {name} already exists") from exc 

120 

121 def delete(self, name: str) -> bool: 

122 # Docstring inherited from ButlerAttributeManager. 

123 numRows = self._db.delete(self._table, ["name"], {"name": name}) 

124 return numRows > 0 

125 

126 def items(self) -> Iterable[tuple[str, str]]: 

127 # Docstring inherited from ButlerAttributeManager. 

128 sql = sqlalchemy.sql.select( 

129 self._table.columns.name, 

130 self._table.columns.value, 

131 ) 

132 with self._db.query(sql) as sql_result: 

133 sql_rows = sql_result.fetchall() 

134 for row in sql_rows: 

135 yield row[0], row[1] 

136 

137 def empty(self) -> bool: 

138 # Docstring inherited from ButlerAttributeManager. 

139 sql = sqlalchemy.sql.select(sqlalchemy.sql.func.count()).select_from(self._table) 

140 with self._db.query(sql) as sql_result: 

141 count = sql_result.scalar() 

142 return count == 0 

143 

144 @classmethod 

145 def currentVersions(cls) -> list[VersionTuple]: 

146 # Docstring inherited from VersionedExtension. 

147 return [_VERSION]