Coverage for python/lsst/daf/butler/registry/opaque.py : 98%

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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/>.
21from __future__ import annotations
22"""The default concrete implementations of the classes that manage
23opaque tables for `Registry`.
24"""
26__all__ = ["ByNameOpaqueTableStorage", "ByNameOpaqueTableStorageManager"]
28from typing import (
29 Any,
30 ClassVar,
31 Iterator,
32 Optional,
33)
35import sqlalchemy
37from ..core.ddl import TableSpec, FieldSpec
38from .interfaces import Database, OpaqueTableStorageManager, OpaqueTableStorage, StaticTablesContext
41class ByNameOpaqueTableStorage(OpaqueTableStorage):
42 """An implementation of `OpaqueTableStorage` that simply creates a true
43 table for each different named opaque logical table.
45 A `ByNameOpaqueTableStorageManager` instance should always be used to
46 construct and manage instances of this class.
48 Parameters
49 ----------
50 db : `Database`
51 Database engine interface for the namespace in which this table lives.
52 name : `str`
53 Name of the logical table (also used as the name of the actual table).
54 table : `sqlalchemy.schema.Table`
55 SQLAlchemy representation of the table, which must have already been
56 created in the namespace managed by ``db`` (this is the responsibility
57 of `ByNameOpaqueTableStorageManager`).
58 """
59 def __init__(self, *, db: Database, name: str, table: sqlalchemy.schema.Table):
60 super().__init__(name=name)
61 self._db = db
62 self._table = table
64 def insert(self, *data: dict):
65 # Docstring inherited from OpaqueTableStorage.
66 self._db.insert(self._table, *data)
68 def fetch(self, **where: Any) -> Iterator[dict]:
69 # Docstring inherited from OpaqueTableStorage.
70 sql = self._table.select().where(
71 sqlalchemy.sql.and_(*[self._table.columns[k] == v for k, v in where.items()])
72 )
73 for row in self._db.query(sql):
74 yield dict(row)
76 def delete(self, **where: Any):
77 # Docstring inherited from OpaqueTableStorage.
78 self._db.delete(self._table, where.keys(), where)
81class ByNameOpaqueTableStorageManager(OpaqueTableStorageManager):
82 """An implementation of `OpaqueTableStorageManager` that simply creates a
83 true table for each different named opaque logical table.
85 Instances of this class should generally be constructed via the
86 `initialize` class method instead of invoking ``__init__`` directly.
88 Parameters
89 ----------
90 db : `Database`
91 Database engine interface for the namespace in which this table lives.
92 metaTable : `sqlalchemy.schema.Table`
93 SQLAlchemy representation of the table that records which opaque
94 logical tables exist.
95 """
96 def __init__(self, db: Database, metaTable: sqlalchemy.schema.Table):
97 self._db = db
98 self._metaTable = metaTable
99 self._storage = {}
101 _META_TABLE_NAME: ClassVar[str] = "opaque_meta"
103 _META_TABLE_SPEC: ClassVar[TableSpec] = TableSpec(
104 fields=[
105 FieldSpec("table_name", dtype=sqlalchemy.String, length=128, primaryKey=True),
106 ],
107 )
109 @classmethod
110 def initialize(cls, db: Database, context: StaticTablesContext) -> OpaqueTableStorageManager:
111 # Docstring inherited from OpaqueTableStorageManager.
112 metaTable = context.addTable(cls._META_TABLE_NAME, cls._META_TABLE_SPEC)
113 return cls(db=db, metaTable=metaTable)
115 def get(self, name: str) -> Optional[OpaqueTableStorage]:
116 # Docstring inherited from OpaqueTableStorageManager.
117 return self._storage.get(name)
119 def register(self, name: str, spec: TableSpec) -> OpaqueTableStorage:
120 # Docstring inherited from OpaqueTableStorageManager.
121 result = self._storage.get(name)
122 if result is None: 122 ↛ 132line 122 didn't jump to line 132, because the condition on line 122 was never false
123 # Create the table itself. If it already exists but wasn't in
124 # the dict because it was added by another client since this one
125 # was initialized, that's fine.
126 table = self._db.ensureTableExists(name, spec)
127 # Add a row to the meta table so we can find this table in the
128 # future. Also okay if that already exists, so we use sync.
129 self._db.sync(self._metaTable, keys={"table_name": name})
130 result = ByNameOpaqueTableStorage(name=name, table=table, db=self._db)
131 self._storage[name] = result
132 return result