#!/usr/bin/env python
import argparse
import glob
import logging
import os
import sys
import time
from collections import defaultdict
from pathlib import Path
from typing import Dict, List, Tuple
import numpy as np
import pytorch_lightning as pl
import torch
from callbacks import Seq2SeqLoggingCallback, get_checkpoint_callback, get_early_stopping_callback
from torch import nn
from torch.utils.data import DataLoader
from transformers import MBartTokenizer, T5ForConditionalGeneration
from transformers.models.bart.modeling_bart import shift_tokens_right
from utils import (
ROUGE_KEYS,
LegacySeq2SeqDataset,
Seq2SeqDataset,
assert_all_frozen,
calculate_bleu,
calculate_rouge,
check_output_dir,
flatten_list,
freeze_embeds,
freeze_params,
get_git_info,
label_smoothed_nll_loss,
lmap,
pickle_save,
save_git_info,
save_json,
use_task_specific_params,
)
# need the parent dir module
sys.path.insert(2, str(Path(__file__).resolve().parents[1]))
from lightning_base import BaseTransformer, add_generic_args, generic_train # noqa
logger = logging.getLogger(__name__)
class SummarizationModule(BaseTransformer):
mode = "summarization"
loss_names = ["loss"]
metric_names = ROUGE_KEYS
default_val_metric = "rouge2"
def __init__(self, hparams, **kwargs):
if hparams.sortish_sampler and hparams.gpus > 1:
hparams.replace_sampler_ddp = False
elif hparams.max_tokens_per_batch is not None:
if hparams.gpus > 1:
raise NotImplementedError("Dynamic Batch size does not work for multi-gpu training")
if hparams.sortish_sampler:
raise ValueError("--sortish_sampler and --max_tokens_per_batch may not be used simultaneously")
super().__init__(hparams, num_labels=None, mode=self.mode, **kwargs)
use_task_specific_params(self.model, "summarization")
save_git_info(self.hparams.output_dir)
self.metrics_save_path = Path(self.output_dir) / "metrics.json"
self.hparams_save_path = Path(self.output_dir) / "hparams.pkl"
pickle_save(self.hparams, self.hparams_save_path)
self.step_count = 0
self.metrics = defaultdict(list)
self.model_type = self.config.model_type
self.vocab_size = self.config.tgt_vocab_size if self.model_type == "fsmt" else self.config.vocab_size
self.dataset_kwargs: dict = {
"data_dir": self.hparams.data_dir,
"max_source_length": self.hparams.max_source_length,
"prefix": self.model.config.prefix or "",
}
n_observations_per_split = {
"train": self.hparams.n_train,
"val": self.hparams.n_val,
"test": self.hparams.n_test,
}
self.n_obs = {k: v if v >= 0 else None for k, v in n_observations_per_split.items()}
self.target_lens = {
"train": self.hparams.max_target_length,
"val": self.hparams.val_max_target_length,
"test": self.hparams.test_max_target_length,
}
assert self.target_lens["train"] <= self.target_lens["val"], f"target_lens: {self.target_lens}"
assert self.target_lens["train"] <= self.target_lens["test"], f"target_lens: {self.target_lens}"
if self.hparams.freeze_embeds:
freeze_embeds(self.model)
if self.hparams.freeze_encoder:
freeze_params(self.model.get_encoder())
assert_all_frozen(self.model.get_encoder())
self.hparams.git_sha = get_git_info()["repo_sha"]
self.num_workers = hparams.num_workers
self.decoder_start_token_id = None # default to config
if self.model.config.decoder_start_token_id is None and isinstance(self.tokenizer, MBartTokenizer):
self.decoder_start_token_id = self.tokenizer.lang_code_to_id[hparams.tgt_lang]
self.model.config.decoder_start_token_id = self.decoder_start_token_id
self.dataset_class = (
Seq2SeqDataset if hasattr(self.tokenizer, "prepare_seq2seq_batch") else LegacySeq2SeqDataset
)
self.already_saved_batch = False
self.eval_beams = self.model.config.num_beams if self.hparams.eval_beams is None else self.hparams.eval_beams
if self.hparams.eval_max_gen_length is not None:
self.eval_max_length = self.hparams.eval_max_gen_length
else:
self.eval_max_length = self.model.config.max_length
self.val_metric = self.default_val_metric if self.hparams.val_metric is None else self.hparams.val_metric
def save_readable_batch(self, batch: Dict[str, torch.Tensor]) -> Dict[str, List[str]]:
"""A debugging utility"""
readable_batch = {
k: self.tokenizer.batch_decode(v.tolist()) if "mask" not in k else v.shape for k, v in batch.items()
}
save_json(readable_batch, Path(self.output_dir) / "text_batch.json")
save_json({k: v.tolist() for k, v in batch.items()}, Path(self.output_dir) / "tok_batch.json")
self.already_saved_batch = True
return readable_batch
def forward(self, input_ids, **kwargs):
return self.model(input_ids, **kwargs)
def ids_to_clean_text(self, generated_ids: List[int]):
gen_text = self.tokenizer.batch_decode(
generated_ids, skip_special_tokens=True, clean_up_tokenization_spaces=True
)
return lmap(str.strip, gen_text)
def _step(self, batch: dict) -> Tuple:
pad_token_id = self.tokenizer.pad_token_id
src_ids, src_mask = batch["input_ids"], batch["attention_mask"]
tgt_ids = batch["labels"]
if isinstance(self.model, T5ForConditionalGeneration):
decoder_input_ids = self.model._shift_right(tgt_ids)
else:
decoder_input_ids = shift_tokens_right(tgt_ids, pad_token_id)
if not self.already_saved_batch: # This would be slightly better if it only happened on rank zero
batch["decoder_input_ids"] = decoder_input_ids
self.save_readable_batch(batch)
outputs = self(src_ids, attention_mask=src_mask, decoder_input_ids=decoder_input_ids, use_cache=False)
lm_logits = outputs["logits"]
if self.hparams.label_smoothing == 0:
# Same behavior as modeling_bart.py, besides ignoring pad_token_id
ce_loss_fct = nn.CrossEntropyLoss(ignore_index=pad_token_id)
assert lm_logits.shape[-1] == self.vocab_size
loss = ce_loss_fct(lm_logits.view(-1, lm_logits.shape[-1]), tgt_ids.view(-1))
else:
lprobs = nn.functional.log_softmax(lm_logits, dim=-1)
loss, nll_loss = label_smoothed_nll_loss(
lprobs, tgt_ids, self.hparams.label_smoothing, ignore_index=pad_token_id
)
return (loss,)
@property
def pad(self) -> int:
return self.tokenizer.pad_token_id
def training_step(self, batch, batch_idx) -> Dict:
loss_tensors = self._step(batch)
logs = dict(zip(self.loss_names, loss_tensors))
# tokens per batch
logs["tpb"] = batch["input_ids"].ne(self.pad).sum() + batch["labels"].ne(self.pad).sum()
logs["bs"] = batch["input_ids"].shape[0]
logs["src_pad_tok"] = batch["input_ids"].eq(self.pad).sum()
logs["src_pad_frac"] = batch["input_ids"].eq(self.pad).float().mean()
# TODO(SS): make a wandb summary metric for this
return {"loss": loss_tensors[0], "log": logs}
def validation_step(self, batch, batch_idx) -> Dict:
return self._generative_step(batch)
def validation_epoch_end(self, outputs, prefix="val") -> Dict:
self.step_count += 1
losses = {k: torch.stack([x[k] for x in outputs]).mean() for k in self.loss_names}
loss = losses["loss"]
generative_metrics = {
k: np.array([x[k] for x in outputs]).mean() for k in self.metric_names + ["gen_time", "gen_len"]
}
metric_val = (
generative_metrics[self.val_metric] if self.val_metric in generative_metrics else losses[self.val_metric]
)
metric_tensor: torch.FloatTensor = torch.tensor(metric_val).type_as(loss)
generative_metrics.update({k: v.item() for k, v in losses.items()})
losses.update(generative_metrics)
all_metrics = {f"{prefix}_avg_{k}": x for k, x in losses.items()}
all_metrics["step_count"] = self.step_count
self.metrics[prefix].append(all_metrics) # callback writes this to self.metrics_save_path
preds = flatten_list([x["preds"] for x in outputs])
return {
"log": all_metrics,
"preds": preds,
f"{prefix}_loss": loss,
f"{prefix}_{self.val_metric}": metric_tensor,
}
def calc_generative_metrics(self, preds, target) -> Dict:
return calculate_rouge(preds, target)
def _generative_step(self, batch: dict) -> dict:
t0 = time.time()
# parser.add_argument('--eval_max_gen_length', type=int, default=None, help='never generate more than n tokens')
generated_ids = self.model.generate(
batch["input_ids"],
attention_mask=batch["attention_mask"],
use_cache=True,
decoder_start_token_id=self.decoder_start_token_id,
num_beams=self.eval_beams,
max_length=self.eval_max_length,
)
gen_time = (time.time() - t0) / batch["input_ids"].shape[0]
preds: List[str] = self.ids_to_clean_text(generated_ids)
target: List[str] = self.ids_to_clean_text(batch["labels"])
loss_tensors = self._step(batch)
base_metrics = dict(zip(self.loss_names, loss_tensors))
rouge: Dict = self.calc_generative_metrics(preds, target)
summ_len = np.mean(lmap(len, generated_ids))
base_metrics.update(gen_time=gen_time, gen_len=summ_len, preds=preds, target=target, **rouge)
return base_metrics
def test_step(self, batch, batch_idx):
return self._generative_step(batch)
def test_epoch_end(self, outputs):
return self.validation_epoch_end(outputs, prefix="test")
def get_dataset(self, type_path) -> Seq2SeqDataset:
n_obs = self.n_obs[type_path]
max_target_length = self.target_lens[type_path]
dataset = self.dataset_class(
self.tokenizer,
type_path=type_path,
n_obs=n_obs,
max_target_length=max_target_length,
**self.dataset_kwargs,
)
return dataset
def get_dataloader(self, type_path: str, batch_size: int, shuffle: bool = False) -> DataLoader:
dataset = self.get_dataset(type_path)
if self.hparams.sortish_sampler and type_path != "test" and type_path != "val":
sampler = dataset.make_sortish_sampler(batch_size, distributed=self.hparams.gpus > 1)
return DataLoader(
dataset,
batch_size=batch_size,
collate_fn=dataset.collate_fn,
shuffle=False,
num_workers=self.num_workers,
sampler=sampler,
)
elif self.hparams.max_tokens_per_batch is not None and type_path != "test" and type_path != "val":
batch_sampler = dataset.make_dynamic_sampler(
self.hparams.max_tokens_per_batch, distributed=self.hparams.gpus > 1
)
return DataLoader(
dataset,
batch_sampler=batch_sampler,
collate_fn=dataset.collate_fn,
# shuffle=False,
num_workers=self.num_workers,
# batch_size=None,
)
else:
return DataLoader(
dataset,
batch_size=batch_size,
collate_fn=dataset.collate_fn,
shuffle=shuffle,
num_workers=self.num_workers,
sampler=None,
)
def train_dataloader(self) -> DataLoader:
dataloader = self.get_dataloader("train", batch_size=self.hparams.train_batch_size, shuffle=True)
return dataloader
def val_dataloader(self) -> DataLoader:
return self.get_dataloader("val", batch_size=self.hparams.eval_batch_size)
def test_dataloader(self) -> DataLoader:
return self.get_dataloader("test", batch_size=self.hparams.eval_batch_size)
@staticmethod
def add_model_specific_args(parser, root_dir):
BaseTransformer.add_model_specific_args(parser, root_dir)
add_generic_args(parser, root_dir)
parser.add_argument(
"--max_source_length",
default=1024,
type=int,
help=(
"The maximum total input sequence length after tokenization. Sequences longer "
"than this will be truncated, sequences shorter will be padded."
),
)
parser.add_argument(
"--max_target_length",
default=56,
type=int,
help=(
"The maximum total input sequence length after tokenization. Sequences longer "
"than this will be truncated, sequences shorter will be padded."
),
)
parser.add_argument(
"--val_max_target_length",
default=142, # these defaults are optimized for CNNDM. For xsum, see README.md.
type=int,
help=(
"The maximum total input sequence length after tokenization. Sequences longer "
"than this will be truncated, sequences shorter will be padded."
),
)
parser.add_argument(
"--test_max_target_length",
default=142,
type=int,
help=(
"The maximum total input sequence length after tokenization. Sequences longer "
"than this will be truncated, sequences shorter will be padded."
),
)
parser.add_argument("--freeze_encoder", action="store_true")
parser.add_argument("--freeze_embeds", action="store_true")
parser.add_argument("--sortish_sampler", action="store_true", default=False)
parser.add_argument("--overwrite_output_dir", action="store_true", default=False)
parser.add_argument("--max_tokens_per_batch", type=int, default=None)
parser.add_argument("--logger_name", type=str, choices=["default", "wandb", "wandb_shared"], default="default")
parser.add_argument("--n_train", type=int, default=-1, required=False, help="# examples. -1 means use all.")
parser.add_argument("--n_val", type=int, default=500, required=False, help="# examples. -1 means use all.")
parser.add_argument("--n_test", type=int, default=-1, required=False, help="# examples. -1 means use all.")
parser.add_argument(
"--task", type=str, default="summarization", required=False, help="# examples. -1 means use all."
)
parser.add_argument("--label_smoothing", type=float, default=0.0, required=False)
parser.add_argument("--src_lang", type=str, default="", required=False)
parser.add_argument("--tgt_lang", type=str, default="", required=False)
parser.add_argument("--eval_beams", type=int, default=None, required=False)
parser.add_argument(
"--val_metric", type=str, default=None, required=False, choices=["bleu", "rouge2", "loss", None]
)
parser.add_argument("--eval_max_gen_length", type=int, default=None, help="never generate more than n tokens")
parser.add_argument("--save_top_k", type=int, default=1, required=False, help="How many checkpoints to save")
parser.add_argument(
"--early_stopping_patience",
type=int,
default=-1,
required=False,
help=(
"-1 means never early stop. early_stopping_patience is measured in validation checks, not epochs. So"
" val_check_interval will effect it."
),
)
return parser
class TranslationModule(SummarizationModule):
mode = "translation"
loss_names = ["loss"]
metric_names = ["bleu"]
default_val_metric = "bleu"
def __init__(self, hparams, **kwargs):
super().__init__(hparams, **kwargs)
self.dataset_kwargs["src_lang"] = hparams.src_lang
self.dataset_kwargs["tgt_lang"] = hparams.tgt_lang
def calc_generative_metrics(self, preds, target) -> dict:
return calculate_bleu(preds, target)
def main(args, model=None) -> SummarizationModule:
Path(args.output_dir).mkdir(exist_ok=True)
check_output_dir(args, expected_items=3)
if model is None:
if "summarization" in args.task:
model: SummarizationModule = SummarizationModule(args)
else:
model: SummarizationModule = TranslationModule(args)
dataset = Path(args.data_dir).name
if (
args.logger_name == "default"
or args.fast_dev_run
or str(args.output_dir).startswith("/tmp")
or str(args.output_dir).startswith("/var")
):
logger = True # don't pollute wandb logs unnecessarily
elif args.logger_name == "wandb":
from pytorch_lightning.loggers import WandbLogger
project = os.environ.get("WANDB_PROJECT", dataset)
logger = WandbLogger(name=model.output_dir.name, project=project)
elif args.logger_name == "wandb_shared":
from pytorch_lightning.loggers import WandbLogger
logger = WandbLogger(name=model.output_dir.name, project=f"hf_{dataset}")
if args.early_stopping_patience >= 0:
es_callback = get_early_stopping_callback(model.val_metric, args.early_stopping_patience)
else:
es_callback = False
lower_is_better = args.val_metric == "loss"
trainer: pl.Trainer = generic_train(
model,
args,
logging_callback=Seq2SeqLoggingCallback(),
checkpoint_callback=get_checkpoint_callback(
args.output_dir, model.val_metric, args.save_top_k, lower_is_better
),
early_stopping_callback=es_callback,
logger=logger,
)
pickle_save(model.hparams, model.output_dir / "hparams.pkl")
if not args.do_predict:
return model
model.hparams.test_checkpoint = ""
checkpoints = sorted(glob.glob(os.path.join(args.output_dir, "*.ckpt"), recursive=True))
if checkpoints:
model.hparams.test_checkpoint = checkpoints[-1]
trainer.resume_from_checkpoint = checkpoints[-1]
trainer.logger.log_hyperparams(model.hparams)
# test() without a model tests using the best checkpoint automatically
trainer.test()
return model
if __name__ == "__main__":
parser = argparse.ArgumentParser()
parser = pl.Trainer.add_argparse_args(parser)
parser = SummarizationModule.add_model_specific_args(parser, os.getcwd())
args = parser.parse_args()
main(args)