def main()

in archived/language-modeling/scripts/run_mlm.py [0:0]


def main():
    # region Argument Parsing
    parser = HfArgumentParser((ModelArguments, DataTrainingArguments, TFTrainingArguments))
    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()

    # Sanity checks
    if (
        data_args.dataset_name is None
        and data_args.train_file is None
        and data_args.validation_file is None
    ):
        raise ValueError("Need either a dataset name or a training/validation file.")
    else:
        if data_args.train_file is not None:
            extension = data_args.train_file.split(".")[-1]
            assert extension in [
                "csv",
                "json",
                "txt",
            ], "`train_file` should be a csv, json or txt file."
        if data_args.validation_file is not None:
            extension = data_args.validation_file.split(".")[-1]
            assert extension in [
                "csv",
                "json",
                "txt",
            ], "`validation_file` should be a csv, json or txt file."

    if training_args.output_dir is not None:
        training_args.output_dir = Path(training_args.output_dir)
        os.makedirs(training_args.output_dir, exist_ok=True)

    if (
        isinstance(training_args.strategy, tf.distribute.TPUStrategy)
        and not data_args.pad_to_max_length
    ):
        logger.warning("We are training on TPU - forcing pad_to_max_length")
        data_args.pad_to_max_length = 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:
        config_path = training_args.output_dir / CONFIG_NAME
        weights_path = training_args.output_dir / TF2_WEIGHTS_NAME
        if config_path.is_file() and weights_path.is_file():
            checkpoint = training_args.output_dir
            logger.warning(
                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 Setup logging
    # accelerator.is_local_main_process is only True for one process per machine.
    logger.setLevel(logging.INFO)
    datasets.utils.logging.set_verbosity_warning()
    transformers.utils.logging.set_verbosity_info()
    # endregion

    # If passed along, set the training seed now.
    if training_args.seed is not None:
        set_seed(training_args.seed)

    # region Load datasets
    # Get the datasets: you can either provide your own CSV/JSON/TXT training and evaluation files (see below)
    # or just provide the name of one of the public datasets available on the hub at https://huggingface.co/datasets/
    # (the dataset will be downloaded automatically from the datasets Hub).
    #
    # For CSV/JSON files, this script will use the column called 'text' or the first column if no column called
    # 'text' is found. 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.
    if data_args.dataset_name is not None:
        # Downloading and loading a dataset from the hub.
        raw_datasets = load_dataset(data_args.dataset_name, data_args.dataset_config_name)
        if "validation" not in raw_datasets.keys():
            raw_datasets["validation"] = load_dataset(
                data_args.dataset_name,
                data_args.dataset_config_name,
                split=f"train[:{data_args.validation_split_percentage}%]",
            )
            raw_datasets["train"] = load_dataset(
                data_args.dataset_name,
                data_args.dataset_config_name,
                split=f"train[{data_args.validation_split_percentage}%:]",
            )
    else:
        data_files = {}
        if data_args.train_file is not None:
            data_files["train"] = data_args.train_file
        if data_args.validation_file is not None:
            data_files["validation"] = data_args.validation_file
        extension = data_args.train_file.split(".")[-1]
        if extension == "txt":
            extension = "text"
        raw_datasets = load_dataset(extension, data_files=data_files)

    # See more about loading any type of standard or custom dataset (from files, python dict, pandas DataFrame, etc) at
    # https://huggingface.co/docs/datasets/loading_datasets.html.
    # endregion

    # region Load pretrained model and tokenizer
    #
    # In distributed training, the .from_pretrained methods guarantee that only one local process can concurrently
    # download model & vocab.
    if checkpoint is not None:
        config = AutoConfig.from_pretrained(checkpoint)
    elif model_args.config_name:
        config = AutoConfig.from_pretrained(model_args.config_name)
    elif model_args.model_name_or_path:
        config = AutoConfig.from_pretrained(model_args.model_name_or_path)
    else:
        config = CONFIG_MAPPING[model_args.model_type]()
        logger.warning("You are instantiating a new config instance from scratch.")

    if model_args.tokenizer_name:
        tokenizer = AutoTokenizer.from_pretrained(model_args.tokenizer_name)
    elif model_args.model_name_or_path:
        tokenizer = AutoTokenizer.from_pretrained(model_args.model_name_or_path)
    else:
        raise ValueError(
            "You are instantiating a new tokenizer from scratch. This is not supported by this script."
            "You can do it from another script, save it, and load it from here, using --tokenizer_name."
        )
    # endregion

    # region Dataset preprocessing
    # First we tokenize all the texts.
    column_names = raw_datasets["train"].column_names
    text_column_name = "text" if "text" in column_names else column_names[0]

    if data_args.max_seq_length is None:
        max_seq_length = tokenizer.model_max_length
        if max_seq_length > 1024:
            logger.warning(
                f"The tokenizer picked seems to have a very large `model_max_length` ({tokenizer.model_max_length}). "
                "Picking 1024 instead. You can reduce that default value by passing --max_seq_length xxx."
            )
            max_seq_length = 1024
    else:
        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)

    if data_args.line_by_line:
        # When using line_by_line, we just tokenize each nonempty line.
        padding = "max_length" if data_args.pad_to_max_length else False

        def tokenize_function(examples):
            # Remove empty lines
            examples[text_column_name] = [
                line for line in examples[text_column_name] if len(line) > 0 and not line.isspace()
            ]
            return tokenizer(
                examples[text_column_name],
                padding=padding,
                truncation=True,
                max_length=max_seq_length,
                # We use this option because DataCollatorForLanguageModeling (see below) is more efficient when it
                # receives the `special_tokens_mask`.
                return_special_tokens_mask=True,
            )

        tokenized_datasets = raw_datasets.map(
            tokenize_function,
            batched=True,
            num_proc=data_args.preprocessing_num_workers,
            remove_columns=[text_column_name],
            load_from_cache_file=not data_args.overwrite_cache,
            desc="Running tokenizer on dataset line_by_line",
        )
    else:
        # Otherwise, we tokenize every text, then concatenate them together before splitting them in smaller parts.
        # We use `return_special_tokens_mask=True` because DataCollatorForLanguageModeling (see below) is more
        # efficient when it receives the `special_tokens_mask`.
        def tokenize_function(examples):
            return tokenizer(examples[text_column_name], return_special_tokens_mask=True)

        tokenized_datasets = raw_datasets.map(
            tokenize_function,
            batched=True,
            num_proc=data_args.preprocessing_num_workers,
            remove_columns=column_names,
            load_from_cache_file=not data_args.overwrite_cache,
            desc="Running tokenizer on every text in dataset",
        )

        # Main data processing function that will concatenate all texts from our dataset and generate chunks of
        # max_seq_length.
        def group_texts(examples):
            # Concatenate all texts.
            concatenated_examples = {k: sum(examples[k], []) for k in examples.keys()}
            total_length = len(concatenated_examples[list(examples.keys())[0]])
            # We drop the small remainder, we could add padding if the model supported it instead of this drop, you can
            # customize this part to your needs.
            if total_length >= max_seq_length:
                total_length = (total_length // max_seq_length) * max_seq_length
            # Split by chunks of max_len.
            result = {
                k: [t[i : i + max_seq_length] for i in range(0, total_length, max_seq_length)]
                for k, t in concatenated_examples.items()
            }
            return result

        # Note that with `batched=True`, this map processes 1,000 texts together, so group_texts throws away a
        # remainder for each of those groups of 1,000 texts. You can adjust that batch_size here but a higher value
        # might be slower to preprocess.
        #
        # To speed up this part, we use multiprocessing. See the documentation of the map method for more information:
        # https://huggingface.co/docs/datasets/package_reference/main_classes.html#datasets.Dataset.map

        tokenized_datasets = tokenized_datasets.map(
            group_texts,
            batched=True,
            num_proc=data_args.preprocessing_num_workers,
            load_from_cache_file=not data_args.overwrite_cache,
            desc=f"Grouping texts in chunks of {max_seq_length}",
        )

    train_dataset = tokenized_datasets["train"]

    if data_args.validation_file is not None:
        eval_dataset = tokenized_datasets["validation"]
    else:
        logger.info(
            f"Validation file not found: using {data_args.validation_split_percentage}% of the dataset as validation as provided in data_args"
        )
        train_indices, val_indices = train_test_split(
            list(range(len(train_dataset))), test_size=data_args.validation_split_percentage / 100
        )

        eval_dataset = train_dataset.select(val_indices)
        train_dataset = train_dataset.select(train_indices)

    if data_args.max_train_samples is not None:
        train_dataset = train_dataset.select(range(data_args.max_train_samples))
    if data_args.max_eval_samples is not None:
        eval_dataset = eval_dataset.select(range(data_args.max_eval_samples))

    # Log a few random samples from the training set:
    for index in random.sample(range(len(train_dataset)), 3):
        logger.info(f"Sample {index} of the training set: {train_dataset[index]}.")
    # endregion

    with training_args.strategy.scope():
        # region Prepare model
        if checkpoint is not None:
            model = TFAutoModelForMaskedLM.from_pretrained(checkpoint, config=config)
        elif model_args.model_name_or_path:
            model = TFAutoModelForMaskedLM.from_pretrained(
                model_args.model_name_or_path, config=config
            )
        else:
            logger.info("Training new model from scratch")
            model = TFAutoModelForMaskedLM.from_config(config)

        model.resize_token_embeddings(len(tokenizer))
        # endregion

        # region TF Dataset preparation
        num_replicas = training_args.strategy.num_replicas_in_sync
        train_generator = partial(sample_generator, train_dataset, tokenizer)
        train_signature = {
            feature: tf.TensorSpec(shape=(None,), dtype=tf.int64)
            for feature in train_dataset.features
            if feature != "special_tokens_mask"
        }
        train_signature["labels"] = train_signature["input_ids"]
        train_signature = (train_signature, train_signature["labels"])
        options = tf.data.Options()
        options.experimental_distribute.auto_shard_policy = tf.data.experimental.AutoShardPolicy.OFF
        tf_train_dataset = (
            tf.data.Dataset.from_generator(train_generator, output_signature=train_signature)
            .with_options(options)
            .batch(
                batch_size=num_replicas * training_args.per_device_train_batch_size,
                drop_remainder=True,
            )
            .repeat(int(training_args.num_train_epochs))
        )
        eval_generator = partial(sample_generator, eval_dataset, tokenizer)
        eval_signature = {
            feature: tf.TensorSpec(shape=(None,), dtype=tf.int64)
            for feature in eval_dataset.features
            if feature != "special_tokens_mask"
        }
        eval_signature["labels"] = eval_signature["input_ids"]
        eval_signature = (eval_signature, eval_signature["labels"])
        tf_eval_dataset = (
            tf.data.Dataset.from_generator(eval_generator, output_signature=eval_signature)
            .with_options(options)
            .batch(
                batch_size=num_replicas * training_args.per_device_eval_batch_size,
                drop_remainder=True,
            )
        )
        # endregion

        # region Optimizer and loss
        batches_per_epoch = len(train_dataset) // (
            num_replicas * training_args.per_device_train_batch_size
        )
        # Bias and layernorm weights are automatically excluded from the decay
        optimizer, lr_schedule = create_optimizer(
            init_lr=training_args.learning_rate,
            num_train_steps=int(training_args.num_train_epochs * batches_per_epoch),
            num_warmup_steps=training_args.warmup_steps,
            adam_beta1=training_args.adam_beta1,
            adam_beta2=training_args.adam_beta2,
            adam_epsilon=training_args.adam_epsilon,
            weight_decay_rate=training_args.weight_decay,
        )

        def dummy_loss(y_true, y_pred):
            return tf.reduce_mean(y_pred)

        model.compile(optimizer=optimizer, loss={"loss": dummy_loss})
        # endregion

        # region Training and validation
        logger.info("***** Running training *****")
        logger.info(f"  Num examples = {len(train_dataset)}")
        logger.info(f"  Num Epochs = {training_args.num_train_epochs}")
        logger.info(
            f"  Instantaneous batch size per device = {training_args.per_device_train_batch_size}"
        )
        logger.info(
            f"  Total train batch size = {training_args.per_device_train_batch_size * num_replicas}"
        )

        history = model.fit(
            tf_train_dataset,
            validation_data=tf_eval_dataset,
            epochs=int(training_args.num_train_epochs),
            steps_per_epoch=len(train_dataset)
            // (training_args.per_device_train_batch_size * num_replicas),
            callbacks=[SavePretrainedCallback(output_dir=training_args.output_dir)],
        )
        try:
            train_perplexity = math.exp(history.history["loss"][-1])
        except OverflowError:
            train_perplexity = math.inf
        try:
            validation_perplexity = math.exp(history.history["val_loss"][-1])
        except OverflowError:
            validation_perplexity = math.inf
        logger.warning(f"  Final train loss: {history.history['loss'][-1]:.3f}")
        logger.warning(f"  Final train perplexity: {train_perplexity:.3f}")
        logger.warning(f"  Final validation loss: {history.history['val_loss'][-1]:.3f}")
        logger.warning(f"  Final validation perplexity: {validation_perplexity:.3f}")
        # endregion

        if training_args.output_dir is not None:
            model.save_pretrained(training_args.output_dir)

    if training_args.push_to_hub:
        # You'll probably want to append some of your own metadata here!
        model.push_to_hub()