Files
AstrAI/astrai/preprocessing/transform.py
T
ViperEkura 31c22dc043 refactor: deduplicate preprocessing kernel and BFD packing
- Extract shared core (mask building, primary-id extraction, tensorisation, position-id generation) to astrai/preprocessing/core.py; Pipeline and TokenizeTransform both consume it, eliminating ~60% duplicated logic
- Promote BFD _plan to module-level plan_bfd(lengths, max_len) returning pure index bins; BFDPacking.apply and evaluate_ifd._pack_bins both call it, removing the second BFD implementation
- Split Pipeline._flush (49 lines) into _inject_doc_reset_position_ids + _inject_continuous_position_ids + _to_tensors; split Pipeline.run by delegating record iteration to core.iter_raw_records
- Remove dead no-op pop/塞回 in Pipeline.run (L110-111)
2026-07-19 12:27:56 +08:00

93 lines
3.3 KiB
Python

"""Tokenization transform for JSONL record streams.
Bridges the Reader layer (``JsonlStore`` reads raw JSON records) and the
Dataset layer (expects per-record tensors). Holds the tokenizer,
mask-builder and position-id strategy together so that I/O code stays
free of model dependencies.
The record-processing core (mask building, primary-id extraction,
per-key tensorisation, position-id generation) is shared with
:class:`astrai.preprocessing.pipeline.Pipeline` via the
:mod:`astrai.preprocessing.core` helpers.
"""
import json
from pathlib import Path
from typing import Dict, List
import torch
from astrai.config.preprocess_config import PipelineConfig
from astrai.preprocessing.core import (
build_position_ids,
build_preprocessing_components,
iter_raw_records,
to_per_record_tensors,
)
class TokenizeTransform:
"""Tokenize raw JSONL record dicts into per-key tensor lists.
Owns the three preprocessing concerns that were previously inlined in
``JsonlStore``: tokenization, loss-mask construction and position-id
generation. Constructing it loads the tokenizer, so it is intentionally
cheap to pass around once built.
Args:
config: Pipeline config describing sections / masks / position mode.
tokenizer_path: Path passed to ``AutoTokenizer.from_pretrained``.
"""
def __init__(self, config: PipelineConfig, tokenizer_path: str):
self.config = config
self.tokenizer, self.mask_builder, self.position_strategy = (
build_preprocessing_components(config, tokenizer_path)
)
@classmethod
def from_config_file(cls, config_path: str) -> "TokenizeTransform":
"""Build from a ``dataset_config.json`` file path.
The config file follows :class:`PipelineConfig` schema with an
extra ``tokenizer_path`` field. When omitted, the config's
parent directory is used as the tokenizer path.
"""
root = Path(config_path).parent
with open(config_path, "r", encoding="utf-8") as f:
raw_config = json.load(f)
tokenizer_path = raw_config.pop("tokenizer_path", None) or str(root)
config = PipelineConfig.from_dict(raw_config)
return cls(config, tokenizer_path)
def apply(self, records: List[dict]) -> Dict[str, list]:
"""Tokenize a list of raw record dicts.
Returns a dict mapping key (``sequence``, ``chosen``, ``responses``,
…) to a list of per-record tensors (or nested tensor lists for
multi-response keys such as GRPO ``responses``).
"""
raw: Dict[str, list] = {}
doc_sequences: List[List[int]] = []
for result in iter_raw_records(
records, self.mask_builder, self.config, self.tokenizer
):
primary = None
for val in result.values():
if isinstance(val, list) and val and isinstance(val[0], int):
primary = val
break
if primary is not None:
doc_sequences.append(primary)
for key, ids in result.items():
raw.setdefault(key, []).append(ids)
tensors = to_per_record_tensors(raw)
pos_ids = build_position_ids(doc_sequences, self.position_strategy)
if pos_ids is not None:
tensors["position_ids"] = [torch.tensor(pos_ids, dtype=torch.int32)]
return tensors