# coding=utf-8
# Copyright 2018 The HuggingFace Inc. team.
#
# 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.
""" Auto Tokenizer class. """
import importlib
import json
import os
from collections import OrderedDict
from typing import TYPE_CHECKING, Dict, Optional, Tuple, Union
from ...configuration_utils import PretrainedConfig
from ...file_utils import (
cached_path,
hf_bucket_url,
is_offline_mode,
is_sentencepiece_available,
is_tokenizers_available,
)
from ...tokenization_utils_base import TOKENIZER_CONFIG_FILE
from ...tokenization_utils_fast import PreTrainedTokenizerFast
from ...utils import logging
from ..encoder_decoder import EncoderDecoderConfig
from .auto_factory import _LazyAutoMapping
from .configuration_auto import (
CONFIG_MAPPING_NAMES,
AutoConfig,
config_class_to_model_type,
model_type_to_module_name,
replace_list_option_in_docstrings,
)
logger = logging.get_logger(__name__)
if TYPE_CHECKING:
# This significantly improves completion suggestion performance when
# the transformers package is used with Microsoft's Pylance language server.
TOKENIZER_MAPPING_NAMES: OrderedDict[str, Tuple[Optional[str], Optional[str]]] = OrderedDict()
else:
TOKENIZER_MAPPING_NAMES = OrderedDict(
[
("retribert", ("RetriBertTokenizer", "RetriBertTokenizerFast" if is_tokenizers_available() else None)),
("roformer", ("RoFormerTokenizer", "RoFormerTokenizerFast" if is_tokenizers_available() else None)),
(
"t5",
(
"T5Tokenizer" if is_sentencepiece_available() else None,
"T5TokenizerFast" if is_tokenizers_available() else None,
),
),
(
"mt5",
(
"MT5Tokenizer" if is_sentencepiece_available() else None,
"MT5TokenizerFast" if is_tokenizers_available() else None,
),
),
("mobilebert", ("MobileBertTokenizer", "MobileBertTokenizerFast" if is_tokenizers_available() else None)),
("distilbert", ("DistilBertTokenizer", "DistilBertTokenizerFast" if is_tokenizers_available() else None)),
(
"albert",
(
"AlbertTokenizer" if is_sentencepiece_available() else None,
"AlbertTokenizerFast" if is_tokenizers_available() else None,
),
),
(
"camembert",
(
"CamembertTokenizer" if is_sentencepiece_available() else None,
"CamembertTokenizerFast" if is_tokenizers_available() else None,
),
),
(
"pegasus",
(
"PegasusTokenizer" if is_sentencepiece_available() else None,
"PegasusTokenizerFast" if is_tokenizers_available() else None,
),
),
(
"mbart",
(
"MBartTokenizer" if is_sentencepiece_available() else None,
"MBartTokenizerFast" if is_tokenizers_available() else None,
),
),
(
"xlm-roberta",
(
"XLMRobertaTokenizer" if is_sentencepiece_available() else None,
"XLMRobertaTokenizerFast" if is_tokenizers_available() else None,
),
),
("marian", ("MarianTokenizer" if is_sentencepiece_available() else None, None)),
("blenderbot-small", ("BlenderbotSmallTokenizer", None)),
("blenderbot", ("BlenderbotTokenizer", None)),
("bart", ("BartTokenizer", "BartTokenizerFast")),
("longformer", ("LongformerTokenizer", "LongformerTokenizerFast" if is_tokenizers_available() else None)),
("roberta", ("RobertaTokenizer", "RobertaTokenizerFast" if is_tokenizers_available() else None)),
(
"reformer",
(
"ReformerTokenizer" if is_sentencepiece_available() else None,
"ReformerTokenizerFast" if is_tokenizers_available() else None,
),
),
("electra", ("ElectraTokenizer", "ElectraTokenizerFast" if is_tokenizers_available() else None)),
("funnel", ("FunnelTokenizer", "FunnelTokenizerFast" if is_tokenizers_available() else None)),
("lxmert", ("LxmertTokenizer", "LxmertTokenizerFast" if is_tokenizers_available() else None)),
("layoutlm", ("LayoutLMTokenizer", "LayoutLMTokenizerFast" if is_tokenizers_available() else None)),
("layoutlmv2", ("LayoutLMv2Tokenizer", "LayoutLMv2TokenizerFast" if is_tokenizers_available() else None)),
(
"dpr",
(
"DPRQuestionEncoderTokenizer",
"DPRQuestionEncoderTokenizerFast" if is_tokenizers_available() else None,
),
),
(
"squeezebert",
("SqueezeBertTokenizer", "SqueezeBertTokenizerFast" if is_tokenizers_available() else None),
),
("bert", ("BertTokenizer", "BertTokenizerFast" if is_tokenizers_available() else None)),
("openai-gpt", ("OpenAIGPTTokenizer", "OpenAIGPTTokenizerFast" if is_tokenizers_available() else None)),
("gpt2", ("GPT2Tokenizer", "GPT2TokenizerFast" if is_tokenizers_available() else None)),
("transfo-xl", ("TransfoXLTokenizer", None)),
(
"xlnet",
(
"XLNetTokenizer" if is_sentencepiece_available() else None,
"XLNetTokenizerFast" if is_tokenizers_available() else None,
),
),
("flaubert", ("FlaubertTokenizer", None)),
("xlm", ("XLMTokenizer", None)),
("ctrl", ("CTRLTokenizer", None)),
("fsmt", ("FSMTTokenizer", None)),
("bert-generation", ("BertGenerationTokenizer" if is_sentencepiece_available() else None, None)),
("deberta", ("DebertaTokenizer", "DebertaTokenizerFast" if is_tokenizers_available() else None)),
("deberta-v2", ("DebertaV2Tokenizer" if is_sentencepiece_available() else None, None)),
("rag", ("RagTokenizer", None)),
("xlm-prophetnet", ("XLMProphetNetTokenizer" if is_sentencepiece_available() else None, None)),
("speech_to_text", ("Speech2TextTokenizer" if is_sentencepiece_available() else None, None)),
("m2m_100", ("M2M100Tokenizer" if is_sentencepiece_available() else None, None)),
("prophetnet", ("ProphetNetTokenizer", None)),
("mpnet", ("MPNetTokenizer", "MPNetTokenizerFast" if is_tokenizers_available() else None)),
("tapas", ("TapasTokenizer", None)),
("led", ("LEDTokenizer", "LEDTokenizerFast" if is_tokenizers_available() else None)),
("convbert", ("ConvBertTokenizer", "ConvBertTokenizerFast" if is_tokenizers_available() else None)),
(
"big_bird",
(
"BigBirdTokenizer" if is_sentencepiece_available() else None,
"BigBirdTokenizerFast" if is_tokenizers_available() else None,
),
),
("ibert", ("RobertaTokenizer", "RobertaTokenizerFast" if is_tokenizers_available() else None)),
("wav2vec2", ("Wav2Vec2CTCTokenizer", None)),
("hubert", ("Wav2Vec2CTCTokenizer", None)),
("gpt_neo", ("GPT2Tokenizer", "GPT2TokenizerFast" if is_tokenizers_available() else None)),
("luke", ("LukeTokenizer", None)),
("bigbird_pegasus", ("PegasusTokenizer", "PegasusTokenizerFast" if is_tokenizers_available() else None)),
("canine", ("CanineTokenizer", None)),
("bertweet", ("BertweetTokenizer", None)),
("bert-japanese", ("BertJapaneseTokenizer", None)),
("splinter", ("SplinterTokenizer", "SplinterTokenizerFast")),
("byt5", ("ByT5Tokenizer", None)),
(
"cpm",
(
"CpmTokenizer" if is_sentencepiece_available() else None,
"CpmTokenizerFast" if is_tokenizers_available() else None,
),
),
("herbert", ("HerbertTokenizer", "HerbertTokenizerFast" if is_tokenizers_available() else None)),
("phobert", ("PhobertTokenizer", None)),
(
"barthez",
(
"BarthezTokenizer" if is_sentencepiece_available() else None,
"BarthezTokenizerFast" if is_tokenizers_available() else None,
),
),
(
"mbart50",
(
"MBart50Tokenizer" if is_sentencepiece_available() else None,
"MBart50TokenizerFast" if is_tokenizers_available() else None,
),
),
(
"rembert",
(
"RemBertTokenizer" if is_sentencepiece_available() else None,
"RemBertTokenizerFast" if is_tokenizers_available() else None,
),
),
(
"clip",
(
"CLIPTokenizer",
"CLIPTokenizerFast" if is_tokenizers_available() else None,
),
),
]
)
TOKENIZER_MAPPING = _LazyAutoMapping(CONFIG_MAPPING_NAMES, TOKENIZER_MAPPING_NAMES)
CONFIG_TO_TYPE = {v: k for k, v in CONFIG_MAPPING_NAMES.items()}
def tokenizer_class_from_name(class_name: str):
if class_name == "PreTrainedTokenizerFast":
return PreTrainedTokenizerFast
for module_name, tokenizers in TOKENIZER_MAPPING_NAMES.items():
if class_name in tokenizers:
module_name = model_type_to_module_name(module_name)
module = importlib.import_module(f".{module_name}", "transformers.models")
return getattr(module, class_name)
return None
def get_tokenizer_config(
pretrained_model_name_or_path: Union[str, os.PathLike],
cache_dir: Optional[Union[str, os.PathLike]] = None,
force_download: bool = False,
resume_download: bool = False,
proxies: Optional[Dict[str, str]] = None,
use_auth_token: Optional[Union[bool, str]] = None,
revision: Optional[str] = None,
local_files_only: bool = False,
**kwargs,
):
"""
Loads the tokenizer configuration from a pretrained model tokenizer configuration.
Args:
pretrained_model_name_or_path (:obj:`str` or :obj:`os.PathLike`):
This can be either:
- a string, the `model id` of a pretrained model configuration hosted inside a model repo on
huggingface.co. Valid model ids can be located at the root-level, like ``bert-base-uncased``, or
namespaced under a user or organization name, like ``dbmdz/bert-base-german-cased``.
- a path to a `directory` containing a configuration file saved using the
:func:`~transformers.PreTrainedTokenizer.save_pretrained` method, e.g., ``./my_model_directory/``.
cache_dir (:obj:`str` or :obj:`os.PathLike`, `optional`):
Path to a directory in which a downloaded pretrained model configuration should be cached if the standard
cache should not be used.
force_download (:obj:`bool`, `optional`, defaults to :obj:`False`):
Whether or not to force to (re-)download the configuration files and override the cached versions if they
exist.
resume_download (:obj:`bool`, `optional`, defaults to :obj:`False`):
Whether or not to delete incompletely received file. Attempts to resume the download if such a file exists.
proxies (:obj:`Dict[str, str]`, `optional`):
A dictionary of proxy servers to use by protocol or endpoint, e.g., :obj:`{'http': 'foo.bar:3128',
'http://hostname': 'foo.bar:4012'}.` The proxies are used on each request.
use_auth_token (:obj:`str` or `bool`, `optional`):
The token to use as HTTP bearer authorization for remote files. If :obj:`True`, will use the token
generated when running :obj:`transformers-cli login` (stored in :obj:`~/.huggingface`).
revision(:obj:`str`, `optional`, defaults to :obj:`"main"`):
The specific model version to use. It can be a branch name, a tag name, or a commit id, since we use a
git-based system for storing models and other artifacts on huggingface.co, so ``revision`` can be any
identifier allowed by git.
local_files_only (:obj:`bool`, `optional`, defaults to :obj:`False`):
If :obj:`True`, will only try to load the tokenizer configuration from local files.
.. note::
Passing :obj:`use_auth_token=True` is required when you want to use a private model.
Returns:
:obj:`Dict`: The configuration of the tokenizer.
Examples::
# Download configuration from huggingface.co and cache.
tokenizer_config = get_tokenizer_config("bert-base-uncased")
# This model does not have a tokenizer config so the result will be an empty dict.
tokenizer_config = get_tokenizer_config("xlm-roberta-base")
# Save a pretrained tokenizer locally and you can reload its config
from transformers import AutoTokenizer
tokenizer = AutoTokenizer.from_pretrained("bert-base-cased")
tokenizer.save_pretrained("tokenizer-test")
tokenizer_config = get_tokenizer_config("tokenizer-test")
"""
if is_offline_mode() and not local_files_only:
logger.info("Offline mode: forcing local_files_only=True")
local_files_only = True
pretrained_model_name_or_path = str(pretrained_model_name_or_path)
if os.path.isdir(pretrained_model_name_or_path):
config_file = os.path.join(pretrained_model_name_or_path, TOKENIZER_CONFIG_FILE)
else:
config_file = hf_bucket_url(
pretrained_model_name_or_path, filename=TOKENIZER_CONFIG_FILE, revision=revision, mirror=None
)
try:
# Load from URL or cache if already cached
resolved_config_file = cached_path(
config_file,
cache_dir=cache_dir,
force_download=force_download,
proxies=proxies,
resume_download=resume_download,
local_files_only=local_files_only,
use_auth_token=use_auth_token,
)
except EnvironmentError:
logger.info("Could not locate the tokenizer configuration file, will try to use the model config instead.")
return {}
with open(resolved_config_file, encoding="utf-8") as reader:
return json.load(reader)
[docs]class AutoTokenizer:
r"""
This is a generic tokenizer class that will be instantiated as one of the tokenizer classes of the library when
created with the :meth:`AutoTokenizer.from_pretrained` class method.
This class cannot be instantiated directly using ``__init__()`` (throws an error).
"""
def __init__(self):
raise EnvironmentError(
"AutoTokenizer is designed to be instantiated "
"using the `AutoTokenizer.from_pretrained(pretrained_model_name_or_path)` method."
)
[docs] @classmethod
@replace_list_option_in_docstrings(TOKENIZER_MAPPING_NAMES)
def from_pretrained(cls, pretrained_model_name_or_path, *inputs, **kwargs):
r"""
Instantiate one of the tokenizer classes of the library from a pretrained model vocabulary.
The tokenizer class to instantiate is selected based on the :obj:`model_type` property of the config object
(either passed as an argument or loaded from :obj:`pretrained_model_name_or_path` if possible), or when it's
missing, by falling back to using pattern matching on :obj:`pretrained_model_name_or_path`:
List options
Params:
pretrained_model_name_or_path (:obj:`str` or :obj:`os.PathLike`):
Can be either:
- A string, the `model id` of a predefined tokenizer hosted inside a model repo on huggingface.co.
Valid model ids can be located at the root-level, like ``bert-base-uncased``, or namespaced under
a user or organization name, like ``dbmdz/bert-base-german-cased``.
- A path to a `directory` containing vocabulary files required by the tokenizer, for instance saved
using the :func:`~transformers.PreTrainedTokenizer.save_pretrained` method, e.g.,
``./my_model_directory/``.
- A path or url to a single saved vocabulary file if and only if the tokenizer only requires a
single vocabulary file (like Bert or XLNet), e.g.: ``./my_model_directory/vocab.txt``. (Not
applicable to all derived classes)
inputs (additional positional arguments, `optional`):
Will be passed along to the Tokenizer ``__init__()`` method.
config (:class:`~transformers.PretrainedConfig`, `optional`)
The configuration object used to dertermine the tokenizer class to instantiate.
cache_dir (:obj:`str` or :obj:`os.PathLike`, `optional`):
Path to a directory in which a downloaded pretrained model configuration should be cached if the
standard cache should not be used.
force_download (:obj:`bool`, `optional`, defaults to :obj:`False`):
Whether or not to force the (re-)download the model weights and configuration files and override the
cached versions if they exist.
resume_download (:obj:`bool`, `optional`, defaults to :obj:`False`):
Whether or not to delete incompletely received files. Will attempt to resume the download if such a
file exists.
proxies (:obj:`Dict[str, str]`, `optional`):
A dictionary of proxy servers to use by protocol or endpoint, e.g., :obj:`{'http': 'foo.bar:3128',
'http://hostname': 'foo.bar:4012'}`. The proxies are used on each request.
revision(:obj:`str`, `optional`, defaults to :obj:`"main"`):
The specific model version to use. It can be a branch name, a tag name, or a commit id, since we use a
git-based system for storing models and other artifacts on huggingface.co, so ``revision`` can be any
identifier allowed by git.
subfolder (:obj:`str`, `optional`):
In case the relevant files are located inside a subfolder of the model repo on huggingface.co (e.g. for
facebook/rag-token-base), specify it here.
use_fast (:obj:`bool`, `optional`, defaults to :obj:`True`):
Whether or not to try to load the fast version of the tokenizer.
kwargs (additional keyword arguments, `optional`):
Will be passed to the Tokenizer ``__init__()`` method. Can be used to set special tokens like
``bos_token``, ``eos_token``, ``unk_token``, ``sep_token``, ``pad_token``, ``cls_token``,
``mask_token``, ``additional_special_tokens``. See parameters in the ``__init__()`` for more details.
Examples::
>>> from transformers import AutoTokenizer
>>> # Download vocabulary from huggingface.co and cache.
>>> tokenizer = AutoTokenizer.from_pretrained('bert-base-uncased')
>>> # Download vocabulary from huggingface.co (user-uploaded) and cache.
>>> tokenizer = AutoTokenizer.from_pretrained('dbmdz/bert-base-german-cased')
>>> # If vocabulary files are in a directory (e.g. tokenizer was saved using `save_pretrained('./test/saved_model/')`)
>>> tokenizer = AutoTokenizer.from_pretrained('./test/bert_saved_model/')
"""
config = kwargs.pop("config", None)
kwargs["_from_auto"] = True
use_fast = kwargs.pop("use_fast", True)
# First, let's try to use the tokenizer_config file to get the tokenizer class.
tokenizer_config = get_tokenizer_config(pretrained_model_name_or_path, **kwargs)
config_tokenizer_class = tokenizer_config.get("tokenizer_class")
# If that did not work, let's try to use the config.
if config_tokenizer_class is None:
if not isinstance(config, PretrainedConfig):
config = AutoConfig.from_pretrained(pretrained_model_name_or_path, **kwargs)
config_tokenizer_class = config.tokenizer_class
# If we have the tokenizer class from the tokenizer config or the model config we're good!
if config_tokenizer_class is not None:
tokenizer_class = None
if use_fast and not config_tokenizer_class.endswith("Fast"):
tokenizer_class_candidate = f"{config_tokenizer_class}Fast"
tokenizer_class = tokenizer_class_from_name(tokenizer_class_candidate)
if tokenizer_class is None:
tokenizer_class_candidate = config_tokenizer_class
tokenizer_class = tokenizer_class_from_name(tokenizer_class_candidate)
if tokenizer_class is None:
raise ValueError(
f"Tokenizer class {tokenizer_class_candidate} does not exist or is not currently imported."
)
return tokenizer_class.from_pretrained(pretrained_model_name_or_path, *inputs, **kwargs)
# Otherwise we have to be creative.
# if model is an encoder decoder, the encoder tokenizer class is used by default
if isinstance(config, EncoderDecoderConfig):
if type(config.decoder) is not type(config.encoder): # noqa: E721
logger.warning(
f"The encoder model config class: {config.encoder.__class__} is different from the decoder model "
f"config class: {config.decoder.__class__}. It is not recommended to use the "
"`AutoTokenizer.from_pretrained()` method in this case. Please use the encoder and decoder "
"specific tokenizer classes."
)
config = config.encoder
model_type = config_class_to_model_type(type(config).__name__)
if model_type is not None:
tokenizer_class_py, tokenizer_class_fast = TOKENIZER_MAPPING[type(config)]
if tokenizer_class_fast and (use_fast or tokenizer_class_py is None):
return tokenizer_class_fast.from_pretrained(pretrained_model_name_or_path, *inputs, **kwargs)
else:
if tokenizer_class_py is not None:
return tokenizer_class_py.from_pretrained(pretrained_model_name_or_path, *inputs, **kwargs)
else:
raise ValueError(
"This tokenizer cannot be instantiated. Please make sure you have `sentencepiece` installed "
"in order to use this tokenizer."
)
raise ValueError(
f"Unrecognized configuration class {config.__class__} to build an AutoTokenizer.\n"
f"Model type should be one of {', '.join(c.__name__ for c in TOKENIZER_MAPPING.keys())}."
)