Coverage for python/lsst/daf/butler/registry/opaque.py: 32%
79 statements
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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.
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9# This software is dual licensed under the GNU General Public License and also
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11# to use; please see the files gpl-3.0.txt and/or bsd_license.txt,
12# respectively. If you choose the GPL option then the following text applies
13# (but note that there is still no warranty even if you opt for BSD instead):
14#
15# This program is free software: you can redistribute it and/or modify
16# it under the terms of the GNU General Public License as published by
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28"""The default concrete implementations of the classes that manage
29opaque tables for `Registry`.
30"""
32from __future__ import annotations
34__all__ = ["ByNameOpaqueTableStorage", "ByNameOpaqueTableStorageManager"]
36import itertools
37from collections.abc import Iterable, Iterator
38from typing import TYPE_CHECKING, Any, ClassVar
40import sqlalchemy
42from .._utilities.thread_safe_cache import ThreadSafeCache
43from ..ddl import FieldSpec, TableSpec
44from .interfaces import (
45 Database,
46 OpaqueTableStorage,
47 OpaqueTableStorageManager,
48 StaticTablesContext,
49 VersionTuple,
50)
52if TYPE_CHECKING:
53 from ..datastore import DatastoreTransaction
55# This has to be updated on every schema change
56_VERSION = VersionTuple(0, 2, 0)
59class ByNameOpaqueTableStorage(OpaqueTableStorage):
60 """An implementation of `OpaqueTableStorage` that simply creates a true
61 table for each different named opaque logical table.
63 A `ByNameOpaqueTableStorageManager` instance should always be used to
64 construct and manage instances of this class.
66 Parameters
67 ----------
68 db : `Database`
69 Database engine interface for the namespace in which this table lives.
70 name : `str`
71 Name of the logical table (also used as the name of the actual table).
72 table : `sqlalchemy.schema.Table`
73 SQLAlchemy representation of the table, which must have already been
74 created in the namespace managed by ``db`` (this is the responsibility
75 of `ByNameOpaqueTableStorageManager`).
76 """
78 def __init__(self, *, db: Database, name: str, table: sqlalchemy.schema.Table):
79 super().__init__(name=name)
80 self._db = db
81 self._table = table
83 def insert(self, *data: dict, transaction: DatastoreTransaction | None = None) -> None:
84 # Docstring inherited from OpaqueTableStorage.
85 # The provided transaction object can be ignored since we rely on
86 # the database itself providing any rollback functionality.
87 self._db.insert(self._table, *data)
89 def ensure(self, *data: dict, transaction: DatastoreTransaction | None = None) -> None:
90 # Docstring inherited from OpaqueTableStorage.
91 # The provided transaction object can be ignored since we rely on
92 # the database itself providing any rollback functionality.
93 self._db.ensure(self._table, *data)
95 def replace(self, *data: dict, transaction: DatastoreTransaction | None = None) -> None:
96 # Docstring inherited from OpaqueTableStorage.
97 # The provided transaction object can be ignored since we rely on
98 # the database itself providing any rollback functionality.
99 self._db.replace(self._table, *data)
101 def fetch(self, **where: Any) -> Iterator[sqlalchemy.RowMapping]:
102 # Docstring inherited from OpaqueTableStorage.
104 def _batch_in_clause(
105 column: sqlalchemy.schema.Column, values: Iterable[Any]
106 ) -> Iterator[sqlalchemy.sql.expression.ClauseElement]:
107 """Split one long IN clause into a series of shorter ones."""
108 in_limit = 1000
109 # We have to remove possible duplicates from values; and in many
110 # cases it should be helpful to order the items in the clause.
111 values = sorted(set(values))
112 for iposn in range(0, len(values), in_limit):
113 in_clause = column.in_(values[iposn : iposn + in_limit])
114 yield in_clause
116 def _batch_in_clauses(**where: Any) -> Iterator[sqlalchemy.sql.expression.ColumnElement]:
117 """Generate a sequence of WHERE clauses with a limited number of
118 items in IN clauses.
119 """
120 batches: list[Iterable[Any]] = []
121 for k, v in where.items():
122 column = self._table.columns[k]
123 if isinstance(v, list | tuple | set):
124 batches.append(_batch_in_clause(column, v))
125 else:
126 # single "batch" for a regular eq operator
127 batches.append([column == v])
129 for clauses in itertools.product(*batches):
130 yield sqlalchemy.sql.and_(*clauses)
132 sql = self._table.select()
133 if where:
134 # Split long IN clauses into shorter batches
135 batched_sql = [sql.where(clause) for clause in _batch_in_clauses(**where)]
136 else:
137 batched_sql = [sql]
138 for sql_batch in batched_sql:
139 with self._db.query(sql_batch) as sql_result:
140 sql_mappings = sql_result.mappings().fetchall()
141 yield from sql_mappings
143 def delete(self, columns: Iterable[str], *rows: dict) -> None:
144 # Docstring inherited from OpaqueTableStorage.
145 self._db.delete(self._table, columns, *rows)
148class ByNameOpaqueTableStorageManager(OpaqueTableStorageManager):
149 """An implementation of `OpaqueTableStorageManager` that simply creates a
150 true table for each different named opaque logical table.
152 Instances of this class should generally be constructed via the
153 `initialize` class method instead of invoking ``__init__`` directly.
155 Parameters
156 ----------
157 db : `Database`
158 Database engine interface for the namespace in which this table lives.
159 metaTable : `sqlalchemy.schema.Table`
160 SQLAlchemy representation of the table that records which opaque
161 logical tables exist.
162 tables : `ThreadSafeCache` [`str`, `~sqlalchemy.schema.Table`]
163 Mapping from string to table, to track which tables have already been
164 created. This mapping is shared between cloned instances of this
165 manager.
166 registry_schema_version : `VersionTuple` or `None`, optional
167 Version of registry schema.
168 """
170 def __init__(
171 self,
172 db: Database,
173 metaTable: sqlalchemy.schema.Table,
174 tables: ThreadSafeCache[str, sqlalchemy.schema.Table],
175 registry_schema_version: VersionTuple | None = None,
176 ):
177 super().__init__(registry_schema_version=registry_schema_version)
178 self._db = db
179 self._metaTable = metaTable
180 self._tables = tables
182 def clone(self, db: Database) -> ByNameOpaqueTableStorageManager:
183 return ByNameOpaqueTableStorageManager(
184 db, self._metaTable, self._tables, self._registry_schema_version
185 )
187 _META_TABLE_NAME: ClassVar[str] = "opaque_meta"
189 _META_TABLE_SPEC: ClassVar[TableSpec] = TableSpec(
190 fields=[
191 FieldSpec("table_name", dtype=sqlalchemy.String, length=128, primaryKey=True),
192 ],
193 )
195 @classmethod
196 def initialize(
197 cls, db: Database, context: StaticTablesContext, registry_schema_version: VersionTuple | None = None
198 ) -> OpaqueTableStorageManager:
199 # Docstring inherited from OpaqueTableStorageManager.
200 metaTable = context.addTable(cls._META_TABLE_NAME, cls._META_TABLE_SPEC)
201 return cls(
202 db=db,
203 metaTable=metaTable,
204 tables=ThreadSafeCache(),
205 registry_schema_version=registry_schema_version,
206 )
208 def get(self, name: str) -> OpaqueTableStorage | None:
209 # Docstring inherited from OpaqueTableStorageManager.
210 table = self._tables.get(name)
211 if table is None:
212 return None
213 return ByNameOpaqueTableStorage(name=name, table=table, db=self._db)
215 def register(self, name: str, spec: TableSpec) -> OpaqueTableStorage:
216 # Docstring inherited from OpaqueTableStorageManager.
217 result = self.get(name)
218 if result is None:
219 # Create the table itself. If it already exists but wasn't in
220 # the dict because it was added by another client since this one
221 # was initialized, that's fine.
222 table = self._db.ensureTableExists(name, spec)
223 # Add a row to the meta table so we can find this table in the
224 # future. Also okay if that already exists, so we use sync.
225 self._db.sync(self._metaTable, keys={"table_name": name})
226 self._tables.set_or_get(name, table)
227 result = self.get(name)
228 assert result is not None
229 return result
231 @classmethod
232 def currentVersions(cls) -> list[VersionTuple]:
233 # Docstring inherited from VersionedExtension.
234 return [_VERSION]