#!/usr/bin/env python # coding=utf-8 # Copyright 2021 The HuggingFace Inc. team. All rights reserved. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. """ Fine-tuning the library models for sequence classification.""" # You can also adapt this script on your own text classification task. Pointers for this are left as comments. import logging import os import random import sys from dataclasses import dataclass, field from math import ceil from pathlib import Path from typing import Optional import numpy as np from datasets import load_dataset from transformers import ( AutoConfig, AutoTokenizer, HfArgumentParser, PretrainedConfig, TFAutoModelForSequenceClassification, TrainingArguments, set_seed, ) from transformers.file_utils import CONFIG_NAME, TF2_WEIGHTS_NAME os.environ["TF_CPP_MIN_LOG_LEVEL"] = "1" # Reduce the amount of console output from TF import tensorflow as tf # noqa: E402 logger = logging.getLogger(__name__) # region Helper classes class DataSequence(tf.keras.utils.Sequence): # We use a Sequence object to load the data. Although it's completely possible to load your data as Numpy/TF arrays # and pass those straight to the Model, this constrains you in a couple of ways. Most notably, it requires all # the data to be padded to the length of the longest input example, and it also requires the whole dataset to be # loaded into memory. If these aren't major problems for you, you can skip the sequence object in your own code! def __init__(self, dataset, non_label_column_names, batch_size, labels, shuffle=True): super().__init__() # Retain all of the columns not present in the original data - these are the ones added by the tokenizer self.data = { key: dataset[key] for key in dataset.features.keys() if key not in non_label_column_names and key != "label" } data_lengths = {len(array) for array in self.data.values()} assert len(data_lengths) == 1, "Dataset arrays differ in length!" self.data_length = data_lengths.pop() self.num_batches = ceil(self.data_length / batch_size) if labels: self.labels = np.array(dataset["label"]) assert len(self.labels) == self.data_length, "Labels not the same length as input arrays!" else: self.labels = None self.batch_size = batch_size self.shuffle = shuffle if self.shuffle: # Shuffle the data order self.permutation = np.random.permutation(self.data_length) else: self.permutation = None def on_epoch_end(self): # If we're shuffling, reshuffle the data order after each epoch if self.shuffle: self.permutation = np.random.permutation(self.data_length) def __getitem__(self, item): # Note that this yields a batch, not a single sample batch_start = item * self.batch_size batch_end = (item + 1) * self.batch_size if self.shuffle: data_indices = self.permutation[batch_start:batch_end] else: data_indices = np.arange(batch_start, batch_end) # We want to pad the data as little as possible, so we only pad each batch # to the maximum length within that batch. We do that by stacking the variable- # length inputs into a ragged tensor and then densifying it. batch_input = { key: tf.ragged.constant([data[i] for i in data_indices]).to_tensor() for key, data in self.data.items() } if self.labels is None: return batch_input else: batch_labels = self.labels[data_indices] return batch_input, batch_labels def __len__(self): return self.num_batches class SavePretrainedCallback(tf.keras.callbacks.Callback): # Hugging Face models have a save_pretrained() method that saves both the weights and the necessary # metadata to allow them to be loaded as a pretrained model in future. This is a simple Keras callback # that saves the model with this method after each epoch. def __init__(self, output_dir, **kwargs): super().__init__() self.output_dir = output_dir def on_epoch_end(self, epoch, logs=None): self.model.save_pretrained(self.output_dir) # endregion # region Command-line arguments @dataclass class DataTrainingArguments: """ Arguments pertaining to what data we are going to input our model for training and eval. Using `HfArgumentParser` we can turn this class into argparse arguments to be able to specify them on the command line. """ train_file: Optional[str] = field( default=None, metadata={"help": "A csv or a json file containing the training data."} ) validation_file: Optional[str] = field( default=None, metadata={"help": "A csv or a json file containing the validation data."} ) test_file: Optional[str] = field(default=None, metadata={"help": "A csv or a json file containing the test data."}) max_seq_length: int = field( default=128, metadata={ "help": "The maximum total input sequence length after tokenization. Sequences longer " "than this will be truncated, sequences shorter will be padded." }, ) overwrite_cache: bool = field( default=False, metadata={"help": "Overwrite the cached preprocessed datasets or not."} ) pad_to_max_length: bool = field( default=False, metadata={ "help": "Whether to pad all samples to `max_seq_length`. " "If False, will pad the samples dynamically when batching to the maximum length in the batch." }, ) max_train_samples: Optional[int] = field( default=None, metadata={ "help": "For debugging purposes or quicker training, truncate the number of training examples to this " "value if set." }, ) max_val_samples: Optional[int] = field( default=None, metadata={ "help": "For debugging purposes or quicker training, truncate the number of validation examples to this " "value if set." }, ) max_test_samples: Optional[int] = field( default=None, metadata={ "help": "For debugging purposes or quicker training, truncate the number of test examples to this " "value if set." }, ) def __post_init__(self): train_extension = self.train_file.split(".")[-1].lower() if self.train_file is not None else None validation_extension = ( self.validation_file.split(".")[-1].lower() if self.validation_file is not None else None ) test_extension = self.test_file.split(".")[-1].lower() if self.test_file is not None else None extensions = {train_extension, validation_extension, test_extension} extensions.discard(None) assert len(extensions) != 0, "Need to supply at least one of --train_file, --validation_file or --test_file!" assert len(extensions) == 1, "All input files should have the same file extension, either csv or json!" assert "csv" in extensions or "json" in extensions, "Input files should have either .csv or .json extensions!" self.input_file_extension = extensions.pop() @dataclass class ModelArguments: """ Arguments pertaining to which model/config/tokenizer we are going to fine-tune from. """ model_name_or_path: str = field( metadata={"help": "Path to pretrained model or model identifier from huggingface.co/models"} ) config_name: Optional[str] = field( default=None, metadata={"help": "Pretrained config name or path if not the same as model_name"} ) tokenizer_name: Optional[str] = field( default=None, metadata={"help": "Pretrained tokenizer name or path if not the same as model_name"} ) cache_dir: Optional[str] = field( default=None, metadata={"help": "Where do you want to store the pretrained models downloaded from huggingface.co"}, ) model_revision: str = field( default="main", metadata={"help": "The specific model version to use (can be a branch name, tag name or commit id)."}, ) use_auth_token: bool = field( default=False, metadata={ "help": "Will use the token generated when running `transformers-cli login` (necessary to use this script " "with private models)." }, ) # endregion def main(): # region Argument parsing # See all possible arguments in src/transformers/training_args.py # or by passing the --help flag to this script. # We now keep distinct sets of args, for a cleaner separation of concerns. parser = HfArgumentParser((ModelArguments, DataTrainingArguments, TrainingArguments)) if len(sys.argv) == 2 and sys.argv[1].endswith(".json"): # If we pass only one argument to the script and it's the path to a json file, # let's parse it to get our arguments. model_args, data_args, training_args = parser.parse_json_file(json_file=os.path.abspath(sys.argv[1])) else: model_args, data_args, training_args = parser.parse_args_into_dataclasses() output_dir = Path(training_args.output_dir) output_dir.mkdir(parents=True, exist_ok=True) # endregion # region Checkpoints # Detecting last checkpoint. checkpoint = None if len(os.listdir(training_args.output_dir)) > 0 and not training_args.overwrite_output_dir: if (output_dir / CONFIG_NAME).is_file() and (output_dir / TF2_WEIGHTS_NAME).is_file(): checkpoint = output_dir logger.info( f"Checkpoint detected, resuming training from checkpoint in {training_args.output_dir}. To avoid this" " behavior, change the `--output_dir` or add `--overwrite_output_dir` to train from scratch." ) else: raise ValueError( f"Output directory ({training_args.output_dir}) already exists and is not empty. " "Use --overwrite_output_dir to continue regardless." ) # endregion # region Logging logging.basicConfig( format="%(asctime)s - %(levelname)s - %(name)s - %(message)s", datefmt="%m/%d/%Y %H:%M:%S", handlers=[logging.StreamHandler(sys.stdout)], ) logger.setLevel(logging.INFO) logger.info(f"Training/evaluation parameters {training_args}") # endregion # region Loading data # For CSV/JSON files, this script will use the 'label' field as the label and the 'sentence1' and optionally # 'sentence2' fields as inputs if they exist. If not, the first two fields not named label are used if at least two # columns are provided. Note that the term 'sentence' can be slightly misleading, as they often contain more than # a single grammatical sentence, when the task requires it. # # If the CSVs/JSONs contain only one non-label column, the script does single sentence classification on this # single column. You can easily tweak this behavior (see below) # # In distributed training, the load_dataset function guarantee that only one local process can concurrently # download the dataset. data_files = {"train": data_args.train_file, "validation": data_args.validation_file, "test": data_args.test_file} data_files = {key: file for key, file in data_files.items() if file is not None} for key in data_files.keys(): logger.info(f"Loading a local file for {key}: {data_files[key]}") if data_args.input_file_extension == "csv": # Loading a dataset from local csv files datasets = load_dataset("csv", data_files=data_files, cache_dir=model_args.cache_dir) else: # Loading a dataset from local json files datasets = load_dataset("json", data_files=data_files, cache_dir=model_args.cache_dir) # See more about loading any type of standard or custom dataset at # https://huggingface.co/docs/datasets/loading_datasets.html. # endregion # region Label preprocessing # If you've passed us a training set, we try to infer your labels from it if "train" in datasets: # By default we assume that if your label column looks like a float then you're doing regression, # and if not then you're doing classification. This is something you may want to change! is_regression = datasets["train"].features["label"].dtype in ["float32", "float64"] if is_regression: num_labels = 1 else: # A useful fast method: # https://huggingface.co/docs/datasets/package_reference/main_classes.html#datasets.Dataset.unique label_list = datasets["train"].unique("label") label_list.sort() # Let's sort it for determinism num_labels = len(label_list) # If you haven't passed a training set, we read label info from the saved model (this happens later) else: num_labels = None label_list = None is_regression = None # endregion # region Load pretrained model and tokenizer # Set seed before initializing model set_seed(training_args.seed) # # In distributed training, the .from_pretrained methods guarantee that only one local process can concurrently # download model & vocab. if checkpoint is not None: config_path = training_args.output_dir elif model_args.config_name: config_path = model_args.config_name else: config_path = model_args.model_name_or_path if num_labels is not None: config = AutoConfig.from_pretrained( config_path, num_labels=num_labels, cache_dir=model_args.cache_dir, revision=model_args.model_revision, use_auth_token=True if model_args.use_auth_token else None, ) else: config = AutoConfig.from_pretrained( config_path, cache_dir=model_args.cache_dir, revision=model_args.model_revision, use_auth_token=True if model_args.use_auth_token else None, ) tokenizer = AutoTokenizer.from_pretrained( model_args.tokenizer_name if model_args.tokenizer_name else model_args.model_name_or_path, cache_dir=model_args.cache_dir, revision=model_args.model_revision, use_auth_token=True if model_args.use_auth_token else None, ) if checkpoint is None: model_path = model_args.model_name_or_path else: model_path = checkpoint model = TFAutoModelForSequenceClassification.from_pretrained( model_path, config=config, cache_dir=model_args.cache_dir, revision=model_args.model_revision, use_auth_token=True if model_args.use_auth_token else None, ) # endregion # region Optimizer, loss and compilation optimizer = tf.keras.optimizers.Adam( learning_rate=training_args.learning_rate, beta_1=training_args.adam_beta1, beta_2=training_args.adam_beta2, epsilon=training_args.adam_epsilon, clipnorm=training_args.max_grad_norm, ) if is_regression: loss = tf.keras.losses.MeanSquaredError() metrics = [] else: loss = tf.keras.losses.SparseCategoricalCrossentropy(from_logits=True) metrics = ["accuracy"] model.compile(optimizer=optimizer, loss=loss, metrics=metrics) # endregion # region Dataset preprocessing # Again, we try to have some nice defaults but don't hesitate to tweak to your use case. column_names = {col for cols in datasets.column_names.values() for col in cols} non_label_column_names = [name for name in column_names if name != "label"] if "sentence1" in non_label_column_names and "sentence2" in non_label_column_names: sentence1_key, sentence2_key = "sentence1", "sentence2" elif "sentence1" in non_label_column_names: sentence1_key, sentence2_key = "sentence1", None else: if len(non_label_column_names) >= 2: sentence1_key, sentence2_key = non_label_column_names[:2] else: sentence1_key, sentence2_key = non_label_column_names[0], None # Padding strategy if data_args.pad_to_max_length: padding = "max_length" else: # We will pad later, dynamically at batch creation, to the max sequence length in each batch padding = False if data_args.max_seq_length > tokenizer.model_max_length: logger.warning( f"The max_seq_length passed ({data_args.max_seq_length}) is larger than the maximum length for the" f"model ({tokenizer.model_max_length}). Using max_seq_length={tokenizer.model_max_length}." ) max_seq_length = min(data_args.max_seq_length, tokenizer.model_max_length) # Ensure that our labels match the model's, if it has some pre-specified if "train" in datasets: if not is_regression and model.config.label2id != PretrainedConfig(num_labels=num_labels).label2id: label_name_to_id = model.config.label2id if list(sorted(label_name_to_id.keys())) == list(sorted(label_list)): label_to_id = label_name_to_id # Use the model's labels else: logger.warning( "Your model seems to have been trained with labels, but they don't match the dataset: ", f"model labels: {list(sorted(label_name_to_id.keys()))}, dataset labels: {list(sorted(label_list))}." "\nIgnoring the model labels as a result.", ) label_to_id = {v: i for i, v in enumerate(label_list)} elif not is_regression: label_to_id = {v: i for i, v in enumerate(label_list)} else: label_to_id = None # Now we've established our label2id, let's overwrite the model config with it. model.config.label2id = label_to_id if model.config.label2id is not None: model.config.id2label = {id: label for label, id in label_to_id.items()} else: model.config.id2label = None else: label_to_id = model.config.label2id # Just load the data from the model if "validation" in datasets and model.config.label2id is not None: validation_label_list = datasets["validation"].unique("label") for val_label in validation_label_list: assert val_label in label_to_id, f"Label {val_label} is in the validation set but not the training set!" def preprocess_function(examples): # Tokenize the texts args = ( (examples[sentence1_key],) if sentence2_key is None else (examples[sentence1_key], examples[sentence2_key]) ) result = tokenizer(*args, padding=padding, max_length=max_seq_length, truncation=True) # Map labels to IDs if model.config.label2id is not None and "label" in examples: result["label"] = [(model.config.label2id[l] if l != -1 else -1) for l in examples["label"]] return result datasets = datasets.map(preprocess_function, batched=True, load_from_cache_file=not data_args.overwrite_cache) if "train" in datasets: train_dataset = datasets["train"] if data_args.max_train_samples is not None: train_dataset = train_dataset.select(range(data_args.max_train_samples)) # Log a few random samples from the training set so we can see that it's working as expected: for index in random.sample(range(len(train_dataset)), 3): logger.info(f"Sample {index} of the training set: {train_dataset[index]}.") if "validation" in datasets: eval_dataset = datasets["validation"] if data_args.max_val_samples is not None: eval_dataset = eval_dataset.select(range(data_args.max_val_samples)) if "test" in datasets: test_dataset = datasets["test"] if data_args.max_test_samples is not None: test_dataset = test_dataset.select(range(data_args.max_test_samples)) # endregion # region Training if "train" in datasets: training_dataset = DataSequence( train_dataset, non_label_column_names, batch_size=training_args.per_device_train_batch_size, labels=True ) if "validation" in datasets: eval_dataset = DataSequence( eval_dataset, non_label_column_names, batch_size=training_args.per_device_eval_batch_size, labels=True ) else: eval_dataset = None callbacks = [SavePretrainedCallback(output_dir=training_args.output_dir)] model.fit( training_dataset, validation_data=eval_dataset, epochs=training_args.num_train_epochs, callbacks=callbacks ) elif "validation" in datasets: # If there's a validation dataset but no training set, just evaluate the metrics eval_dataset = DataSequence( eval_dataset, non_label_column_names, batch_size=training_args.per_device_eval_batch_size, labels=True ) logger.info("Computing metrics on validation data...") if is_regression: loss = model.evaluate(eval_dataset) logger.info(f"Loss: {loss:.5f}") else: loss, accuracy = model.evaluate(eval_dataset) logger.info(f"Loss: {loss:.5f}, Accuracy: {accuracy * 100:.4f}%") # endregion # region Prediction if "test" in datasets: logger.info("Doing predictions on test dataset...") test_dataset = DataSequence( test_dataset, non_label_column_names, batch_size=training_args.per_device_eval_batch_size, labels=False ) predictions = model.predict(test_dataset)["logits"] predictions = np.squeeze(predictions) if is_regression else np.argmax(predictions, axis=1) output_test_file = os.path.join(training_args.output_dir, "test_results.txt") with open(output_test_file, "w") as writer: writer.write("index\tprediction\n") for index, item in enumerate(predictions): if is_regression: writer.write(f"{index}\t{item:3.3f}\n") else: item = model.config.id2label[item] writer.write(f"{index}\t{item}\n") logger.info(f"Wrote predictions to {output_test_file}!") # endregion if __name__ == "__main__": main()