Coverage for python / lsst / pipe / base / quantum_graph / _multiblock.py: 39%
288 statements
« prev ^ index » next coverage.py v7.13.1, created at 2026-01-20 01:37 -0800
1# This file is part of pipe_base.
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 software is dual licensed under the GNU General Public License and also
10# under a 3-clause BSD license. Recipients may choose which of these licenses
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
17# the Free Software Foundation, either version 3 of the License, or
18# (at your option) any later version.
19#
20# This program is distributed in the hope that it will be useful,
21# but WITHOUT ANY WARRANTY; without even the implied warranty of
22# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
23# GNU General Public License for more details.
24#
25# You should have received a copy of the GNU General Public License
26# along with this program. If not, see <http://www.gnu.org/licenses/>.
28from __future__ import annotations
30__all__ = (
31 "Address",
32 "AddressReader",
33 "AddressRow",
34 "AddressWriter",
35 "Compressor",
36 "Decompressor",
37 "InvalidQuantumGraphFileError",
38 "MultiblockReader",
39 "MultiblockWriter",
40)
42import dataclasses
43import logging
44import tempfile
45import uuid
46from collections.abc import Iterator
47from contextlib import contextmanager
48from io import BufferedReader, BytesIO
49from operator import attrgetter
50from typing import IO, TYPE_CHECKING, Protocol, TypeAlias, TypeVar
52import pydantic
54if TYPE_CHECKING:
55 import zipfile
58_LOG = logging.getLogger(__name__)
61_T = TypeVar("_T", bound=pydantic.BaseModel)
64UUID_int: TypeAlias = int
66MAX_UUID_INT: UUID_int = 2**128
69DEFAULT_PAGE_SIZE: int = 5_000_000
70"""Default page size for reading chunks of quantum graph files.
72This is intended to be large enough to avoid any possibility of individual
73reads suffering from per-seek overheads, especially in network file access,
74while still being small enough to only minimally slow down tiny reads of
75individual quanta (especially for execution).
76"""
79class Compressor(Protocol):
80 """A protocol for objects with a `compress` method that takes and returns
81 `bytes`.
82 """
84 def compress(self, data: bytes) -> bytes:
85 """Compress the given data.
87 Parameters
88 ----------
89 data : `bytes`
90 Uncompressed data.
92 Returns
93 -------
94 compressed : `bytes`
95 Compressed data.
96 """
97 ...
100class Decompressor(Protocol):
101 """A protocol for objects with a `decompress` method that takes and returns
102 `bytes`.
103 """
105 def decompress(self, data: bytes) -> bytes:
106 """Decompress the given data.
108 Parameters
109 ----------
110 data : `bytes`
111 Compressed data.
113 Returns
114 -------
115 decompressed : `bytes`
116 Uncompressed data.
117 """
118 ...
121class InvalidQuantumGraphFileError(RuntimeError):
122 """An exception raised when a quantum graph file has internal
123 inconsistencies or does not actually appear to be a quantum graph file.
124 """
127@dataclasses.dataclass(slots=True)
128class Address:
129 """Struct that holds an address into a multi-block file."""
131 offset: int = 0
132 """Byte offset for the block."""
134 size: int = 0
135 """Size of the block.
137 This always includes the size of the tiny header that records the block
138 size. That header does not include the size of the header, so these sizes
139 differ by the ``int_size`` used to write the multi-block file.
141 A size of zero is used (with, by convention, an offset of zero) to indicate
142 an absent block.
143 """
145 def __str__(self) -> str:
146 return f"{self.offset:06}[{self.size:06}]"
149@dataclasses.dataclass(slots=True)
150class AddressRow:
151 """The in-memory representation of a single row in an address file."""
153 key: uuid.UUID
154 """Universally unique identifier for this row."""
156 index: int
157 """Monotonically increasing integer ID; unique within this file only."""
159 addresses: list[Address] = dataclasses.field(default_factory=list)
160 """Offsets and sizes into multi-block files."""
162 def write(self, stream: IO[bytes], int_size: int) -> None:
163 """Write this address row to a file-like object.
165 Parameters
166 ----------
167 stream : `typing.IO` [ `bytes` ]
168 Binary file-like object.
169 int_size : `int`
170 Number of bytes to use for all integers.
171 """
172 stream.write(self.key.bytes)
173 stream.write(self.index.to_bytes(int_size))
174 for address in self.addresses:
175 stream.write(address.offset.to_bytes(int_size))
176 stream.write(address.size.to_bytes(int_size))
178 @classmethod
179 def read(cls, stream: IO[bytes], n_addresses: int, int_size: int) -> AddressRow:
180 """Read this address row from a file-like object.
182 Parameters
183 ----------
184 stream : `typing.IO` [ `bytes` ]
185 Binary file-like object.
186 n_addresses : `int`
187 Number of addresses included in each row.
188 int_size : `int`
189 Number of bytes to use for all integers.
190 """
191 key = uuid.UUID(int=int.from_bytes(stream.read(16)))
192 index = int.from_bytes(stream.read(int_size))
193 row = AddressRow(key, index)
194 for _ in range(n_addresses):
195 offset = int.from_bytes(stream.read(int_size))
196 size = int.from_bytes(stream.read(int_size))
197 row.addresses.append(Address(offset, size))
198 return row
200 def __str__(self) -> str:
201 return f"{self.key} {self.index:06} {' '.join(str(a) for a in self.addresses)}"
204@dataclasses.dataclass
205class AddressWriter:
206 """A helper object for writing address files for multi-block files."""
208 addresses: list[dict[uuid.UUID, Address]] = dataclasses.field(default_factory=list)
209 """Addresses to store with each UUID.
211 Every key in one of these dictionaries must have an entry in `indices`.
212 The converse is not true.
213 """
215 def write(self, stream: IO[bytes], int_size: int) -> None:
216 """Write all addresses to a file-like object.
218 Parameters
219 ----------
220 stream : `typing.IO` [ `bytes` ]
221 Binary file-like object.
222 int_size : `int`
223 Number of bytes to use for all integers.
224 """
225 indices: set[uuid.UUID] = set()
226 for address_map in self.addresses:
227 indices.update(address_map.keys())
228 stream.write(int_size.to_bytes(1))
229 stream.write(len(indices).to_bytes(int_size))
230 stream.write(len(self.addresses).to_bytes(int_size))
231 empty_address = Address()
232 for n, key in enumerate(sorted(indices, key=attrgetter("int"))):
233 row = AddressRow(key, n, [m.get(key, empty_address) for m in self.addresses])
234 _LOG.debug("Wrote address %s.", row)
235 row.write(stream, int_size)
237 def write_to_zip(self, zf: zipfile.ZipFile, name: str, int_size: int) -> None:
238 """Write all addresses to a file in a zip archive.
240 Parameters
241 ----------
242 zf : `zipfile.ZipFile`
243 Zip archive to add the file to.
244 name : `str`
245 Base name for the address file; an extension will be added.
246 int_size : `int`
247 Number of bytes to use for all integers.
248 """
249 with zf.open(f"{name}.addr", mode="w") as stream:
250 self.write(stream, int_size=int_size)
253@dataclasses.dataclass
254class AddressPage:
255 """A page of addresses in the `AddressReader`."""
257 file_offset: int
258 """Offset in bytes to this page from the beginning of the file."""
260 begin: int
261 """Index of the first row in this page."""
263 n_rows: int
264 """Number of rows in this page."""
266 read: bool = False
267 """Whether this page has already been read."""
269 @property
270 def end(self) -> int:
271 """One past the last row index in this page."""
272 return self.begin + self.n_rows
275@dataclasses.dataclass
276class PageBounds:
277 """A page index and the UUID interval that page covers."""
279 page_index: int
280 """Index into the page array."""
282 uuid_int_begin: UUID_int
283 """Integer representation of the smallest UUID in this page."""
285 uuid_int_end: UUID_int
286 """One larger than the integer representation of the largest UUID in this
287 page.
288 """
290 def __str__(self) -> str:
291 return f"{self.page_index} [{self.uuid_int_begin:x}:{self.uuid_int_end:x}]"
294@dataclasses.dataclass
295class AddressReader:
296 """A helper object for reading address files for multi-block files."""
298 stream: IO[bytes]
299 """Stream to read from."""
301 int_size: int
302 """Size of each integer in bytes."""
304 n_rows: int
305 """Number of rows in the file."""
307 n_addresses: int
308 """Number of addresses in each row."""
310 rows_per_page: int
311 """Number of addresses in each page."""
313 rows: dict[uuid.UUID, AddressRow] = dataclasses.field(default_factory=dict)
314 """Rows that have already been read."""
316 pages: list[AddressPage] = dataclasses.field(default_factory=list)
317 """Descriptions of the file offsets and integer row indexes of pages and
318 flags for whether they have been read already.
319 """
321 page_bounds: dict[int, PageBounds] = dataclasses.field(default_factory=dict)
322 """Mapping from page index to page boundary information."""
324 @classmethod
325 def from_stream(
326 cls, stream: IO[bytes], *, page_size: int, n_addresses: int, int_size: int
327 ) -> AddressReader:
328 """Construct from a stream by reading the header.
330 Parameters
331 ----------
332 stream : `typing.IO` [ `bytes` ]
333 File-like object to read from.
334 page_size : `int`
335 Approximate number of bytes to read at a time when searching for an
336 address.
337 n_addresses : `int`
338 Number of addresses to expect per row. This is checked against
339 the size embedded in the file.
340 int_size : `int`
341 Number of bytes to use for all integers. This is checked against
342 the size embedded in the file.
343 """
344 header_size = cls.compute_header_size(int_size)
345 row_size = cls.compute_row_size(int_size, n_addresses)
346 # Read the raw header page.
347 header_page_data = stream.read(header_size)
348 if len(header_page_data) < header_size:
349 raise InvalidQuantumGraphFileError("Address file unexpectedly truncated.")
350 # Interpret the raw header data and initialize the reader instance.
351 header_page_stream = BytesIO(header_page_data)
352 file_int_size = int.from_bytes(header_page_stream.read(1))
353 if file_int_size != int_size:
354 raise InvalidQuantumGraphFileError(
355 f"int size in address file ({file_int_size}) does not match int size in header ({int_size})."
356 )
357 n_rows = int.from_bytes(header_page_stream.read(int_size))
358 file_n_addresses = int.from_bytes(header_page_stream.read(int_size))
359 if file_n_addresses != n_addresses:
360 raise InvalidQuantumGraphFileError(
361 f"Incorrect number of addresses per row: expected {n_addresses}, got {file_n_addresses}."
362 )
363 rows_per_page = max(page_size // row_size, 1)
364 # Construct an instance.
365 self = cls(stream, int_size, n_rows, n_addresses, rows_per_page=rows_per_page)
366 # Calculate positions of each page of rows.
367 row_index = 0
368 file_offset = header_size
369 while row_index < n_rows:
370 self.pages.append(AddressPage(file_offset=file_offset, begin=row_index, n_rows=rows_per_page))
371 row_index += rows_per_page
372 file_offset += rows_per_page * row_size
373 if row_index != n_rows:
374 # Last page was too big.
375 self.pages[-1].n_rows -= row_index - n_rows
376 assert sum(p.n_rows for p in self.pages) == n_rows, "Bad logic setting page row counts."
377 return self
379 @classmethod
380 @contextmanager
381 def open_in_zip(
382 cls,
383 zf: zipfile.ZipFile,
384 name: str,
385 *,
386 page_size: int,
387 n_addresses: int,
388 int_size: int,
389 ) -> Iterator[AddressReader]:
390 """Make a reader for an address file in a zip archive.
392 Parameters
393 ----------
394 zf : `zipfile.ZipFile`
395 Zip archive to read the file from.
396 name : `str`
397 Base name for the address file; an extension will be added.
398 page_size : `int`
399 Approximate number of bytes to read at a time when searching for an
400 address.
401 n_addresses : `int`
402 Number of addresses to expect per row. This is checked against
403 the size embedded in the file.
404 int_size : `int`
405 Number of bytes to use for all integers. This is checked against
406 the size embedded in the file.
408 Returns
409 -------
410 reader : `contextlib.AbstractContextManager` [ `AddressReader` ]
411 Context manager that returns a reader when entered.
412 """
413 with zf.open(f"{name}.addr", mode="r") as stream:
414 yield cls.from_stream(stream, page_size=page_size, n_addresses=n_addresses, int_size=int_size)
416 @staticmethod
417 def compute_header_size(int_size: int) -> int:
418 """Return the size (in bytes) of the header of an address file.
420 Parameters
421 ----------
422 int_size : `int`
423 Size of each integer in bytes.
425 Returns
426 -------
427 size : `int`
428 Size of the header in bytes.
429 """
430 return (
431 1 # int_size
432 + int_size # number of rows
433 + int_size # number of addresses in each row
434 )
436 @staticmethod
437 def compute_row_size(int_size: int, n_addresses: int) -> int:
438 """Return the size (in bytes) of each row of an address file.
440 Parameters
441 ----------
442 int_size : `int`
443 Size of each integer in bytes.
444 n_addresses : `int`
445 Number of addresses in each row.
447 Returns
448 -------
449 size : `int`
450 Size of each row in bytes.
451 """
452 return (
453 16 # uuid
454 + int_size
455 * (
456 1 # index
457 + 2 * n_addresses
458 )
459 )
461 @property
462 def row_size(self) -> int:
463 """The size (in bytes) of each row of this address file."""
464 return self.compute_row_size(self.int_size, self.n_addresses)
466 def read_all(self) -> dict[uuid.UUID, AddressRow]:
467 """Read all addresses in the file.
469 Returns
470 -------
471 rows : `dict` [ `uuid.UUID`, `AddressRow` ]
472 Mapping of loaded address rows, keyed by UUID.
473 """
474 # Skip any pages from the beginning that have already been read; this
475 # nicely handles both the case where we already read everything (or
476 # there was nothing to read) while giving us a page with a file offset
477 # to start from.
478 for page in self.pages:
479 if not page.read:
480 break
481 else:
482 return self.rows
483 # Read the entire rest of the file into memory.
484 self.stream.seek(page.file_offset)
485 data = self.stream.read()
486 buffer = BytesIO(data)
487 # Shortcut out if we've already read everything, but don't bother
488 # optimizing previous partial reads.
489 while len(self.rows) < self.n_rows:
490 self._read_row(buffer)
491 # Delete all pages; they don't matter anymore, and that's easier than
492 # updating them to reflect the reads we've done.
493 self.pages.clear()
494 return self.rows
496 def find(self, key: uuid.UUID) -> AddressRow:
497 """Read the row for the given UUID or integer index.
499 Parameters
500 ----------
501 key : `uuid.UUID`
502 UUID to find.
504 Returns
505 -------
506 row : `AddressRow`
507 Addresses for the given UUID.
508 """
509 if (row := self.rows.get(key)) is not None:
510 return row
511 if self.n_rows == 0 or not self.pages:
512 raise LookupError(f"Address for {key} not found.")
514 # Use a binary search to find the page containing the target UUID.
515 left = 0
516 right = len(self.pages) - 1
517 while left <= right:
518 mid = left + ((right - left) // 2)
519 self._read_page(mid)
520 if (row := self.rows.get(key)) is not None:
521 return row
522 bounds = self.page_bounds[mid]
523 if key.int < bounds.uuid_int_begin:
524 right = mid - 1
525 elif key.int > bounds.uuid_int_end:
526 left = mid + 1
527 else:
528 # Should have been on this page, but it wasn't.
529 raise LookupError(f"Address for {key} not found.")
531 # Ran out of pages to search.
532 raise LookupError(f"Address for {key} not found.")
534 def _read_page(self, page_index: int, page_stream: BytesIO | None = None) -> bool:
535 page = self.pages[page_index]
536 if page.read:
537 return False
538 if page_stream is None:
539 self.stream.seek(page.file_offset)
540 page_stream = BytesIO(self.stream.read(page.n_rows * self.row_size))
541 row = self._read_row(page_stream)
542 uuid_int_begin = row.key.int
543 for _ in range(1, page.n_rows):
544 row = self._read_row(page_stream)
545 uuid_int_end = row.key.int + 1 # Python's loop scoping rules are actually useful here!
546 page.read = True
547 bounds = PageBounds(page_index=page_index, uuid_int_begin=uuid_int_begin, uuid_int_end=uuid_int_end)
548 self.page_bounds[page_index] = bounds
549 _LOG.debug("Read page %s with rows [%s:%s].", bounds, page.begin, page.end)
550 return True
552 def _read_row(self, page_stream: BytesIO) -> AddressRow:
553 row = AddressRow.read(page_stream, self.n_addresses, self.int_size)
554 self.rows[row.key] = row
555 _LOG.debug("Read address row %s.", row)
556 return row
559@dataclasses.dataclass
560class MultiblockWriter:
561 """A helper object for writing multi-block files."""
563 stream: IO[bytes]
564 """A binary file-like object to write to."""
566 int_size: int
567 """Number of bytes to use for all integers."""
569 file_size: int = 0
570 """Running size of the full file."""
572 addresses: dict[uuid.UUID, Address] = dataclasses.field(default_factory=dict)
573 """Running map of all addresses added to the file so far.
575 When the multi-block file is fully written, this is appended to the
576 `AddressWriter.addresses` to write the corresponding address file.
577 """
579 @classmethod
580 @contextmanager
581 def open_in_zip(
582 cls, zf: zipfile.ZipFile, name: str, int_size: int, use_tempfile: bool = False
583 ) -> Iterator[MultiblockWriter]:
584 """Open a writer for a file in a zip archive.
586 Parameters
587 ----------
588 zf : `zipfile.ZipFile`
589 Zip archive to add the file to.
590 name : `str`
591 Base name for the multi-block file; an extension will be added.
592 int_size : `int`
593 Number of bytes to use for all integers.
594 use_tempfile : `bool`, optional
595 If `True`, send writes to a temporary file and only add the file to
596 the zip archive when the context manager closes. This involves
597 more overall I/O, but it permits multiple multi-block files to be
598 open for writing in the same zip archive at once.
600 Returns
601 -------
602 writer : `contextlib.AbstractContextManager` [ `MultiblockWriter` ]
603 Context manager that returns a writer when entered.
604 """
605 filename = f"{name}.mb"
606 if use_tempfile:
607 with tempfile.NamedTemporaryFile(suffix=filename) as tmp:
608 yield MultiblockWriter(tmp, int_size)
609 tmp.flush()
610 zf.write(tmp.name, filename)
611 else:
612 with zf.open(f"{name}.mb", mode="w", force_zip64=True) as stream:
613 yield MultiblockWriter(stream, int_size)
615 def write_bytes(self, id: uuid.UUID, data: bytes) -> Address:
616 """Write raw bytes to the multi-block file.
618 Parameters
619 ----------
620 id : `uuid.UUID`
621 Unique ID of the object described by this block.
622 data : `bytes`
623 Data to store directly.
625 Returns
626 -------
627 address : `Address`
628 Address of the bytes just written.
629 """
630 assert id not in self.addresses, "Duplicate write to multi-block file detected."
631 self.stream.write(len(data).to_bytes(self.int_size))
632 self.stream.write(data)
633 block_size = len(data) + self.int_size
634 address = Address(offset=self.file_size, size=block_size)
635 self.file_size += block_size
636 self.addresses[id] = address
637 return address
639 def write_model(self, id: uuid.UUID, model: pydantic.BaseModel, compressor: Compressor) -> Address:
640 """Write raw bytes to the multi-block file.
642 Parameters
643 ----------
644 id : `uuid.UUID`
645 Unique ID of the object described by this block.
646 model : `pydantic.BaseModel`
647 Model to convert to JSON and compress.
648 compressor : `Compressor`
649 Object with a `compress` method that takes and returns `bytes`.
651 Returns
652 -------
653 address : `Address`
654 Address of the bytes just written.
655 """
656 json_data = model.model_dump_json().encode()
657 compressed_data = compressor.compress(json_data)
658 return self.write_bytes(id, compressed_data)
661@dataclasses.dataclass
662class MultiblockReader:
663 """A helper object for reader multi-block files."""
665 stream: IO[bytes]
666 """A binary file-like object to read from."""
668 int_size: int
669 """Number of bytes to use for all integers."""
671 @classmethod
672 @contextmanager
673 def open_in_zip(cls, zf: zipfile.ZipFile, name: str, *, int_size: int) -> Iterator[MultiblockReader]:
674 """Open a reader for a file in a zip archive.
676 Parameters
677 ----------
678 zf : `zipfile.ZipFile`
679 Zip archive to read the file from.
680 name : `str`
681 Base name for the multi-block file; an extension will be added.
682 int_size : `int`
683 Number of bytes to use for all integers.
685 Returns
686 -------
687 reader : `contextlib.AbstractContextManager` [ `MultiblockReader` ]
688 Context manager that returns a reader when entered.
689 """
690 with zf.open(f"{name}.mb", mode="r") as stream:
691 yield MultiblockReader(stream, int_size)
693 @classmethod
694 def read_all_bytes_in_zip(
695 cls, zf: zipfile.ZipFile, name: str, *, int_size: int, page_size: int
696 ) -> Iterator[bytes]:
697 """Iterate over all of the byte blocks in a file in a zip archive.
699 Parameters
700 ----------
701 zf : `zipfile.ZipFile`
702 Zip archive to read the file from.
703 name : `str`
704 Base name for the multi-block file; an extension will be added.
705 int_size : `int`
706 Number of bytes to use for all integers.
707 page_size : `int`
708 Approximate number of bytes to read at a time.
710 Returns
711 -------
712 byte_iter : `~collections.abc.Iterator` [ `bytes` ]
713 Iterator over blocks.
714 """
715 with zf.open(f"{name}.mb", mode="r") as zf_stream:
716 # The standard library typing of IO[bytes] tiers isn't consistent.
717 buffered_stream = BufferedReader(zf_stream) # type: ignore[type-var]
718 size_data = buffered_stream.read(int_size)
719 while size_data:
720 internal_size = int.from_bytes(size_data)
721 yield buffered_stream.read(internal_size)
722 size_data = buffered_stream.read(int_size)
724 @classmethod
725 def read_all_models_in_zip(
726 cls,
727 zf: zipfile.ZipFile,
728 name: str,
729 model_type: type[_T],
730 decompressor: Decompressor,
731 *,
732 int_size: int,
733 page_size: int,
734 ) -> Iterator[_T]:
735 """Iterate over all of the models in a file in a zip archive.
737 Parameters
738 ----------
739 zf : `zipfile.ZipFile`
740 Zip archive to read the file from.
741 name : `str`
742 Base name for the multi-block file; an extension will be added.
743 model_type : `type` [ `pydantic.BaseModel` ]
744 Pydantic model to validate JSON with.
745 decompressor : `Decompressor`
746 Object with a `decompress` method that takes and returns `bytes`.
747 int_size : `int`
748 Number of bytes to use for all integers.
749 page_size : `int`
750 Approximate number of bytes to read at a time.
752 Returns
753 -------
754 model_iter : `~collections.abc.Iterator` [ `pydantic.BaseModel` ]
755 Iterator over model instances.
756 """
757 for compressed_data in cls.read_all_bytes_in_zip(zf, name, int_size=int_size, page_size=page_size):
758 json_data = decompressor.decompress(compressed_data)
759 yield model_type.model_validate_json(json_data)
761 def read_bytes(self, address: Address) -> bytes | None:
762 """Read raw bytes from the multi-block file.
764 Parameters
765 ----------
766 address : `Address`
767 Offset and size of the data to read.
769 Returns
770 -------
771 data : `bytes` or `None`
772 Data read directly, or `None` if the address has zero size.
773 """
774 if not address.size:
775 return None
776 self.stream.seek(address.offset)
777 data = self.stream.read(address.size)
778 internal_size = int.from_bytes(data[: self.int_size])
779 data = data[self.int_size :]
780 if len(data) != internal_size:
781 raise InvalidQuantumGraphFileError(
782 f"Internal size {internal_size} does not match loaded data size {len(data)}."
783 )
784 return data
786 def read_model(self, address: Address, model_type: type[_T], decompressor: Decompressor) -> _T | None:
787 """Read a single compressed JSON block.
789 Parameters
790 ----------
791 address : `Address`
792 Size and offset of the block.
793 model_type : `type` [ `pydantic.BaseModel` ]
794 Pydantic model to validate JSON with.
795 decompressor : `Decompressor`
796 Object with a `decompress` method that takes and returns `bytes`.
798 Returns
799 -------
800 model : `pydantic.BaseModel`
801 Validated model.
802 """
803 compressed_data = self.read_bytes(address)
804 if compressed_data is None:
805 return None
806 json_data = decompressor.decompress(compressed_data)
807 return model_type.model_validate_json(json_data)