# coding=utf-8
# Copyright 2018 The Google AI Language Team Authors and The HuggingFace Inc. team.
# Copyright (c) 2018, NVIDIA CORPORATION. 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.
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""" Configuration base class and utilities."""
import copy
import json
import os
import re
import warnings
from typing import Any, Dict, List, Optional, Tuple, Union
from packaging import version
from . import __version__
from .dynamic_module_utils import custom_object_save
from .utils import (
CONFIG_NAME,
PushToHubMixin,
add_model_info_to_auto_map,
cached_file,
copy_func,
download_url,
extract_commit_hash,
is_remote_url,
is_torch_available,
logging,
)
logger = logging.get_logger(__name__)
_re_configuration_file = re.compile(r"config\.(.*)\.json")
class PretrainedConfig(PushToHubMixin):
# no-format
r"""
Base class for all configuration classes. Handles a few parameters common to all models' configurations as well as
methods for loading/downloading/saving configurations.
A configuration file can be loaded and saved to disk. Loading the configuration file and using this file to
initialize a model does **not** load the model weights. It only affects the model's configuration.
Class attributes (overridden by derived classes):
- **model_type** (`str`) -- An identifier for the model type, serialized into the JSON file, and used to recreate
the correct object in [`~transformers.AutoConfig`].
- **is_composition** (`bool`) -- Whether the config class is composed of multiple sub-configs. In this case the
config has to be initialized from two or more configs of type [`~transformers.PretrainedConfig`] like:
[`~transformers.EncoderDecoderConfig`] or [`~RagConfig`].
- **keys_to_ignore_at_inference** (`List[str]`) -- A list of keys to ignore by default when looking at dictionary
outputs of the model during inference.
- **attribute_map** (`Dict[str, str]`) -- A dict that maps model specific attribute names to the standardized
naming of attributes.
Common attributes (present in all subclasses):
- **vocab_size** (`int`) -- The number of tokens in the vocabulary, which is also the first dimension of the
embeddings matrix (this attribute may be missing for models that don't have a text modality like ViT).
- **hidden_size** (`int`) -- The hidden size of the model.
- **num_attention_heads** (`int`) -- The number of attention heads used in the multi-head attention layers of the
model.
- **num_hidden_layers** (`int`) -- The number of blocks in the model.
Arg:
name_or_path (`str`, *optional*, defaults to `""`):
Store the string that was passed to [`PreTrainedModel.from_pretrained`] or
[`TFPreTrainedModel.from_pretrained`] as `pretrained_model_name_or_path` if the configuration was created
with such a method.
output_hidden_states (`bool`, *optional*, defaults to `False`):
Whether or not the model should return all hidden-states.
output_attentions (`bool`, *optional*, defaults to `False`):
Whether or not the model should returns all attentions.
return_dict (`bool`, *optional*, defaults to `True`):
Whether or not the model should return a [`~transformers.utils.ModelOutput`] instead of a plain tuple.
is_encoder_decoder (`bool`, *optional*, defaults to `False`):
Whether the model is used as an encoder/decoder or not.
is_decoder (`bool`, *optional*, defaults to `False`):
Whether the model is used as decoder or not (in which case it's used as an encoder).
cross_attention_hidden_size** (`bool`, *optional*):
The hidden size of the cross-attention layer in case the model is used as a decoder in an encoder-decoder
setting and the cross-attention hidden dimension differs from `self.config.hidden_size`.
add_cross_attention (`bool`, *optional*, defaults to `False`):
Whether cross-attention layers should be added to the model. Note, this option is only relevant for models
that can be used as decoder models within the [`EncoderDecoderModel`] class, which consists of all models
in `AUTO_MODELS_FOR_CAUSAL_LM`.
tie_encoder_decoder (`bool`, *optional*, defaults to `False`):
Whether all encoder weights should be tied to their equivalent decoder weights. This requires the encoder
and decoder model to have the exact same parameter names.
prune_heads (`Dict[int, List[int]]`, *optional*, defaults to `{}`):
Pruned heads of the model. The keys are the selected layer indices and the associated values, the list of
heads to prune in said layer.
For instance `{1: [0, 2], 2: [2, 3]}` will prune heads 0 and 2 on layer 1 and heads 2 and 3 on layer 2.
chunk_size_feed_forward (`int`, *optional*, defaults to `0`):
The chunk size of all feed forward layers in the residual attention blocks. A chunk size of `0` means that
the feed forward layer is not chunked. A chunk size of n means that the feed forward layer processes `n` <
sequence_length embeddings at a time. For more information on feed forward chunking, see [How does Feed
Forward Chunking work?](../glossary.html#feed-forward-chunking).
> Parameters for sequence generation
max_length (`int`, *optional*, defaults to 20):
Maximum length that will be used by default in the `generate` method of the model.
min_length (`int`, *optional*, defaults to 0):
Minimum length that will be used by default in the `generate` method of the model.
do_sample (`bool`, *optional*, defaults to `False`):
Flag that will be used by default in the `generate` method of the model. Whether or not to use sampling ;
use greedy decoding otherwise.
early_stopping (`bool`, *optional*, defaults to `False`):
Flag that will be used by default in the `generate` method of the model. Whether to stop the beam search
when at least `num_beams` sentences are finished per batch or not.
num_beams (`int`, *optional*, defaults to 1):
Number of beams for beam search that will be used by default in the `generate` method of the model. 1 means
no beam search.
num_beam_groups (`int`, *optional*, defaults to 1):
Number of groups to divide `num_beams` into in order to ensure diversity among different groups of beams
that will be used by default in the `generate` method of the model. 1 means no group beam search.
diversity_penalty (`float`, *optional*, defaults to 0.0):
Value to control diversity for group beam search. that will be used by default in the `generate` method of
the model. 0 means no diversity penalty. The higher the penalty, the more diverse are the outputs.
temperature (`float`, *optional*, defaults to 1.0):
The value used to module the next token probabilities that will be used by default in the `generate` method
of the model. Must be strictly positive.
top_k (`int`, *optional*, defaults to 50):
Number of highest probability vocabulary tokens to keep for top-k-filtering that will be used by default in
the `generate` method of the model.
top_p (`float`, *optional*, defaults to 1):
Value that will be used by default in the `generate` method of the model for `top_p`. If set to float < 1,
only the most probable tokens with probabilities that add up to `top_p` or higher are kept for generation.
typical_p (`float`, *optional*, defaults to 1):
Local typicality measures how similar the conditional probability of predicting a target token next is to
the expected conditional probability of predicting a random token next, given the partial text already
generated. If set to float < 1, the smallest set of the most locally typical tokens with probabilities that
add up to `typical_p` or higher are kept for generation. See [this
paper](https://arxiv.org/pdf/2202.00666.pdf) for more details.
repetition_penalty (`float`, *optional*, defaults to 1):
Parameter for repetition penalty that will be used by default in the `generate` method of the model. 1.0
means no penalty.
length_penalty (`float`, *optional*, defaults to 1):
Exponential penalty to the length that is used with beam-based generation. It is applied as an exponent to
the sequence length, which in turn is used to divide the score of the sequence. Since the score is the log
likelihood of the sequence (i.e. negative), `length_penalty` > 0.0 promotes longer sequences, while
`length_penalty` < 0.0 encourages shorter sequences.
no_repeat_ngram_size (`int`, *optional*, defaults to 0) -- Value that will be used by default in the
`generate` method of the model for `no_repeat_ngram_size`. If set to int > 0, all ngrams of that size can
only occur once.
encoder_no_repeat_ngram_size (`int`, *optional*, defaults to 0) -- Value that will be used by
default in the `generate` method of the model for `encoder_no_repeat_ngram_size`. If set to int > 0, all
ngrams of that size that occur in the `encoder_input_ids` cannot occur in the `decoder_input_ids`.
bad_words_ids (`List[int]`, *optional*):
List of token ids that are not allowed to be generated that will be used by default in the `generate`
method of the model. In order to get the tokens of the words that should not appear in the generated text,
use `tokenizer.encode(bad_word, add_prefix_space=True)`.
num_return_sequences (`int`, *optional*, defaults to 1):
Number of independently computed returned sequences for each element in the batch that will be used by
default in the `generate` method of the model.
output_scores (`bool`, *optional*, defaults to `False`):
Whether the model should return the logits when used for generation.
return_dict_in_generate (`bool`, *optional*, defaults to `False`):
Whether the model should return a [`~transformers.utils.ModelOutput`] instead of a `torch.LongTensor`.
forced_bos_token_id (`int`, *optional*):
The id of the token to force as the first generated token after the `decoder_start_token_id`. Useful for
multilingual models like [mBART](../model_doc/mbart) where the first generated token needs to be the target
language token.
forced_eos_token_id (`int`, *optional*):
The id of the token to force as the last generated token when `max_length` is reached.
remove_invalid_values (`bool`, *optional*):
Whether to remove possible _nan_ and _inf_ outputs of the model to prevent the generation method to crash.
Note that using `remove_invalid_values` can slow down generation.
> Parameters for fine-tuning tasks
architectures (`List[str]`, *optional*):
Model architectures that can be used with the model pretrained weights.
finetuning_task (`str`, *optional*):
Name of the task used to fine-tune the model. This can be used when converting from an original (TensorFlow
or PyTorch) checkpoint.
id2label (`Dict[int, str]`, *optional*):
A map from index (for instance prediction index, or target index) to label.
label2id (`Dict[str, int]`, *optional*): A map from label to index for the model.
num_labels (`int`, *optional*):
Number of labels to use in the last layer added to the model, typically for a classification task.
task_specific_params (`Dict[str, Any]`, *optional*):
Additional keyword arguments to store for the current task.
problem_type (`str`, *optional*):
Problem type for `XxxForSequenceClassification` models. Can be one of `"regression"`,
`"single_label_classification"` or `"multi_label_classification"`.
> Parameters linked to the tokenizer
tokenizer_class (`str`, *optional*):
The name of the associated tokenizer class to use (if none is set, will use the tokenizer associated to the
model by default).
prefix (`str`, *optional*):
A specific prompt that should be added at the beginning of each text before calling the model.
bos_token_id (`int`, *optional*): The id of the _beginning-of-stream_ token.
pad_token_id (`int`, *optional*): The id of the _padding_ token.
eos_token_id (`int`, *optional*): The id of the _end-of-stream_ token.
decoder_start_token_id (`int`, *optional*):
If an encoder-decoder model starts decoding with a different token than _bos_, the id of that token.
sep_token_id (`int`, *optional*): The id of the _separation_ token.
> PyTorch specific parameters
torchscript (`bool`, *optional*, defaults to `False`):
Whether or not the model should be used with Torchscript.
tie_word_embeddings (`bool`, *optional*, defaults to `True`):
Whether the model's input and output word embeddings should be tied. Note that this is only relevant if the
model has a output word embedding layer.
torch_dtype (`str`, *optional*):
The `dtype` of the weights. This attribute can be used to initialize the model to a non-default `dtype`
(which is normally `float32`) and thus allow for optimal storage allocation. For example, if the saved
model is `float16`, ideally we want to load it back using the minimal amount of memory needed to load
`float16` weights. Since the config object is stored in plain text, this attribute contains just the
floating type string without the `torch.` prefix. For example, for `torch.float16` ``torch_dtype` is the
`"float16"` string.
This attribute is currently not being used during model loading time, but this may change in the future
versions. But we can already start preparing for the future by saving the dtype with save_pretrained.
attn_implementation (`str`, *optional*):
The attention implementation to use in the model. Can be any of `"eager"` (manual implementation of the attention), `"sdpa"` (attention using [`torch.nn.functional.scaled_dot_product_attention`](https://pytorch.org/docs/master/generated/torch.nn.functional.scaled_dot_product_attention.html)), or `"flash_attention_2"` (attention using [Dao-AILab/flash-attention](https://github.com/Dao-AILab/flash-attention)). By default, if available, SDPA will be used for torch>=2.1.1. The default is otherwise the manual `"eager"` implementation.
> TensorFlow specific parameters
use_bfloat16 (`bool`, *optional*, defaults to `False`):
Whether or not the model should use BFloat16 scalars (only used by some TensorFlow models).
tf_legacy_loss (`bool`, *optional*, defaults to `False`):
Whether the model should use legacy TensorFlow losses. Legacy losses have variable output shapes and may
not be XLA-compatible. This option is here for backward compatibility and will be removed in Transformers
v5.
"""
model_type: str = ""
is_composition: bool = False
attribute_map: Dict[str, str] = {}
_auto_class: Optional[str] = None
def __setattr__(self, key, value):
if key in super().__getattribute__("attribute_map"):
key = super().__getattribute__("attribute_map")[key]
super().__setattr__(key, value)
def __getattribute__(self, key):
if key != "attribute_map" and key in super().__getattribute__("attribute_map"):
key = super().__getattribute__("attribute_map")[key]
return super().__getattribute__(key)
def __init__(self, **kwargs):
# Attributes with defaults
self.return_dict = kwargs.pop("return_dict", True)
self.output_hidden_states = kwargs.pop("output_hidden_states", False)
self.output_attentions = kwargs.pop("output_attentions", False)
self.torchscript = kwargs.pop("torchscript", False) # Only used by PyTorch models
self.torch_dtype = kwargs.pop("torch_dtype", None) # Only used by PyTorch models
self.use_bfloat16 = kwargs.pop("use_bfloat16", False)
self.tf_legacy_loss = kwargs.pop("tf_legacy_loss", False) # Only used by TensorFlow models
self.pruned_heads = kwargs.pop("pruned_heads", {})
self.tie_word_embeddings = kwargs.pop(
"tie_word_embeddings", True
) # Whether input and output word embeddings should be tied for all MLM, LM and Seq2Seq models.
# Is decoder is used in encoder-decoder models to differentiate encoder from decoder
self.is_encoder_decoder = kwargs.pop("is_encoder_decoder", False)
self.is_decoder = kwargs.pop("is_decoder", False)
self.cross_attention_hidden_size = kwargs.pop("cross_attention_hidden_size", None)
self.add_cross_attention = kwargs.pop("add_cross_attention", False)
self.tie_encoder_decoder = kwargs.pop("tie_encoder_decoder", False)
# Parameters for sequence generation
self.max_length = kwargs.pop("max_length", 20)
self.min_length = kwargs.pop("min_length", 0)
self.do_sample = kwargs.pop("do_sample", False)
self.early_stopping = kwargs.pop("early_stopping", False)
self.num_beams = kwargs.pop("num_beams", 1)
self.num_beam_groups = kwargs.pop("num_beam_groups", 1)
self.diversity_penalty = kwargs.pop("diversity_penalty", 0.0)
self.temperature = kwargs.pop("temperature", 1.0)
self.top_k = kwargs.pop("top_k", 50)
self.top_p = kwargs.pop("top_p", 1.0)
self.typical_p = kwargs.pop("typical_p", 1.0)
self.repetition_penalty = kwargs.pop("repetition_penalty", 1.0)
self.length_penalty = kwargs.pop("length_penalty", 1.0)
self.no_repeat_ngram_size = kwargs.pop("no_repeat_ngram_size", 0)
self.encoder_no_repeat_ngram_size = kwargs.pop("encoder_no_repeat_ngram_size", 0)
self.bad_words_ids = kwargs.pop("bad_words_ids", None)
self.num_return_sequences = kwargs.pop("num_return_sequences", 1)
self.chunk_size_feed_forward = kwargs.pop("chunk_size_feed_forward", 0)
self.output_scores = kwargs.pop("output_scores", False)
self.return_dict_in_generate = kwargs.pop("return_dict_in_generate", False)
self.forced_bos_token_id = kwargs.pop("forced_bos_token_id", None)
self.forced_eos_token_id = kwargs.pop("forced_eos_token_id", None)
self.remove_invalid_values = kwargs.pop("remove_invalid_values", False)
self.exponential_decay_length_penalty = kwargs.pop("exponential_decay_length_penalty", None)
self.suppress_tokens = kwargs.pop("suppress_tokens", None)
self.begin_suppress_tokens = kwargs.pop("begin_suppress_tokens", None)
# Fine-tuning task arguments
self.architectures = kwargs.pop("architectures", None)
self.finetuning_task = kwargs.pop("finetuning_task", None)
self.id2label = kwargs.pop("id2label", None)
self.label2id = kwargs.pop("label2id", None)
if self.label2id is not None and not isinstance(self.label2id, dict):
raise ValueError("Argument label2id should be a dictionary.")
if self.id2label is not None:
if not isinstance(self.id2label, dict):
raise ValueError("Argument id2label should be a dictionary.")
num_labels = kwargs.pop("num_labels", None)
if num_labels is not None and len(self.id2label) != num_labels:
logger.warning(
f"You passed along `num_labels={num_labels}` with an incompatible id to label map: "
f"{self.id2label}. The number of labels wil be overwritten to {self.num_labels}."
)
self.id2label = {int(key): value for key, value in self.id2label.items()}
# Keys are always strings in JSON so convert ids to int here.
else:
self.num_labels = kwargs.pop("num_labels", 2)
if self.torch_dtype is not None and isinstance(self.torch_dtype, str):
# we will start using self.torch_dtype in v5, but to be consistent with
# from_pretrained's torch_dtype arg convert it to an actual torch.dtype object
if is_torch_available():
import torch
self.torch_dtype = getattr(torch, self.torch_dtype)
# Tokenizer arguments TODO: eventually tokenizer and models should share the same config
self.tokenizer_class = kwargs.pop("tokenizer_class", None)
self.prefix = kwargs.pop("prefix", None)
self.bos_token_id = kwargs.pop("bos_token_id", None)
self.pad_token_id = kwargs.pop("pad_token_id", None)
self.eos_token_id = kwargs.pop("eos_token_id", None)
self.sep_token_id = kwargs.pop("sep_token_id", None)
self.decoder_start_token_id = kwargs.pop("decoder_start_token_id", None)
# task specific arguments
self.task_specific_params = kwargs.pop("task_specific_params", None)
# regression / multi-label classification
self.problem_type = kwargs.pop("problem_type", None)
allowed_problem_types = ("regression", "single_label_classification", "multi_label_classification")
if self.problem_type is not None and self.problem_type not in allowed_problem_types:
raise ValueError(
f"The config parameter `problem_type` was not understood: received {self.problem_type} "
"but only 'regression', 'single_label_classification' and 'multi_label_classification' are valid."
)
# TPU arguments
if kwargs.pop("xla_device", None) is not None:
logger.warning(
"The `xla_device` argument has been deprecated in v4.4.0 of Transformers. It is ignored and you can "
"safely remove it from your `config.json` file."
)
# Name or path to the pretrained checkpoint
self._name_or_path = str(kwargs.pop("name_or_path", ""))
# Config hash
self._commit_hash = kwargs.pop("_commit_hash", None)
# Attention implementation to use, if relevant.
self._attn_implementation_internal = kwargs.pop("attn_implementation", None)
# Drop the transformers version info
self.transformers_version = kwargs.pop("transformers_version", None)
# Deal with gradient checkpointing
if kwargs.get("gradient_checkpointing", False):
warnings.warn(
"Passing `gradient_checkpointing` to a config initialization is deprecated and will be removed in v5 "
"Transformers. Using `model.gradient_checkpointing_enable()` instead, or if you are using the "
"`Trainer` API, pass `gradient_checkpointing=True` in your `TrainingArguments`."
)
# Additional attributes without default values
for key, value in kwargs.items():
try:
setattr(self, key, value)
except AttributeError as err:
logger.error(f"Can't set {key} with value {value} for {self}")
raise err
@property
def name_or_path(self) -> str:
return getattr(self, "_name_or_path", None)
@name_or_path.setter
def name_or_path(self, value):
self._name_or_path = str(value) # Make sure that name_or_path is a string (for JSON encoding)
@property
def use_return_dict(self) -> bool:
"""
`bool`: Whether or not return [`~utils.ModelOutput`] instead of tuples.
"""
# If torchscript is set, force `return_dict=False` to avoid jit errors
return self.return_dict and not self.torchscript
@property
def num_labels(self) -> int:
"""
`int`: The number of labels for classification models.
"""
return len(self.id2label)
@num_labels.setter
def num_labels(self, num_labels: int):
if not hasattr(self, "id2label") or self.id2label is None or len(self.id2label) != num_labels:
self.id2label = {i: f"LABEL_{i}" for i in range(num_labels)}
self.label2id = dict(zip(self.id2label.values(), self.id2label.keys()))
@property
def _attn_implementation(self):
# This property is made private for now (as it cannot be changed and a PreTrainedModel.use_attn_implementation method needs to be implemented.)
if hasattr(self, "_attn_implementation_internal"):
if self._attn_implementation_internal is None:
# `config.attn_implementation` should never be None, for backward compatibility.
return "eager"
else:
return self._attn_implementation_internal
else:
return "eager"
@_attn_implementation.setter
def _attn_implementation(self, value):
self._attn_implementation_internal = value
def save_pretrained(self, save_directory: Union[str, os.PathLike], push_to_hub: bool = False, **kwargs):
"""
Save a configuration object to the directory `save_directory`, so that it can be re-loaded using the
[`~PretrainedConfig.from_pretrained`] class method.
Args:
save_directory (`str` or `os.PathLike`):
Directory where the configuration JSON file will be saved (will be created if it does not exist).
push_to_hub (`bool`, *optional*, defaults to `False`):
Whether or not to push your model to the Hugging Face model hub after saving it. You can specify the
repository you want to push to with `repo_id` (will default to the name of `save_directory` in your
namespace).
kwargs (`Dict[str, Any]`, *optional*):
Additional key word arguments passed along to the [`~utils.PushToHubMixin.push_to_hub`] method.
"""
self._set_token_in_kwargs(kwargs)
if os.path.isfile(save_directory):
raise AssertionError(f"Provided path ({save_directory}) should be a directory, not a file")
os.makedirs(save_directory, exist_ok=True)
if push_to_hub:
commit_message = kwargs.pop("commit_message", None)
repo_id = kwargs.pop("repo_id", save_directory.split(os.path.sep)[-1])
repo_id = self._create_repo(repo_id, **kwargs)
files_timestamps = self._get_files_timestamps(save_directory)
# If we have a custom config, we copy the file defining it in the folder and set the attributes so it can be
# loaded from the Hub.
if self._auto_class is not None:
custom_object_save(self, save_directory, config=self)
# If we save using the predefined names, we can load using `from_pretrained`
output_config_file = os.path.join(save_directory, CONFIG_NAME)
self.to_json_file(output_config_file, use_diff=True)
logger.info(f"Configuration saved in {output_config_file}")
if push_to_hub:
self._upload_modified_files(
save_directory,
repo_id,
files_timestamps,
commit_message=commit_message,
token=kwargs.get("token"),
)
@staticmethod
def _set_token_in_kwargs(kwargs, token=None):
"""Temporary method to deal with `token` and `use_auth_token`.
This method is to avoid apply the same changes in all model config classes that overwrite `from_pretrained`.
Need to clean up `use_auth_token` in a follow PR.
"""
# Some model config classes like CLIP define their own `from_pretrained` without the new argument `token` yet.
if token is None:
token = kwargs.pop("token", None)
use_auth_token = kwargs.pop("use_auth_token", None)
if use_auth_token is not None:
warnings.warn(
"The `use_auth_token` argument is deprecated and will be removed in v5 of Transformers. Please use `token` instead.",
FutureWarning,
)
if token is not None:
raise ValueError(
"`token` and `use_auth_token` are both specified. Please set only the argument `token`."
)
token = use_auth_token
if token is not None:
kwargs["token"] = token
@classmethod
def from_pretrained(
cls,
pretrained_model_name_or_path: Union[str, os.PathLike],
cache_dir: Optional[Union[str, os.PathLike]] = None,
force_download: bool = False,
local_files_only: bool = False,
token: Optional[Union[str, bool]] = None,
revision: str = "main",
**kwargs,
) -> "PretrainedConfig":
r"""
Instantiate a [`PretrainedConfig`] (or a derived class) from a pretrained model configuration.
Args:
pretrained_model_name_or_path (`str` or `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
[`~PretrainedConfig.save_pretrained`] method, e.g., `./my_model_directory/`.
- a path or url to a saved configuration JSON *file*, e.g., `./my_model_directory/configuration.json`.
cache_dir (`str` or `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 (`bool`, *optional*, defaults to `False`):
Whether or not to force to (re-)download the configuration files and override the cached versions if
they exist.
resume_download (`bool`, *optional*, defaults to `False`):
Whether or not to delete incompletely received file. Attempts to resume the download if such a file
exists.
proxies (`Dict[str, str]`, *optional*):
A dictionary of proxy servers to use by protocol or endpoint, e.g., `{'http': 'foo.bar:3128',
'http://hostname': 'foo.bar:4012'}.` The proxies are used on each request.
token (`str` or `bool`, *optional*):
The token to use as HTTP bearer authorization for remote files. If `True`, or not specified, will use
the token generated when running `huggingface-cli login` (stored in `~/.huggingface`).
revision (`str`, *optional*, defaults to `"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.
To test a pull request you made on the Hub, you can pass `revision="refs/pr/".
return_unused_kwargs (`bool`, *optional*, defaults to `False`):
If `False`, then this function returns just the final configuration object.
If `True`, then this functions returns a `Tuple(config, unused_kwargs)` where *unused_kwargs* is a
dictionary consisting of the key/value pairs whose keys are not configuration attributes: i.e., the
part of `kwargs` which has not been used to update `config` and is otherwise ignored.
subfolder (`str`, *optional*, defaults to `""`):
In case the relevant files are located inside a subfolder of the model repo on huggingface.co, you can
specify the folder name here.
kwargs (`Dict[str, Any]`, *optional*):
The values in kwargs of any keys which are configuration attributes will be used to override the loaded
values. Behavior concerning key/value pairs whose keys are *not* configuration attributes is controlled
by the `return_unused_kwargs` keyword parameter.
Returns:
[`PretrainedConfig`]: The configuration object instantiated from this pretrained model.
Examples:
```python
# We can't instantiate directly the base class *PretrainedConfig* so let's show the examples on a
# derived class: BertConfig
config = BertConfig.from_pretrained(
"bert-base-uncased"
) # Download configuration from huggingface.co and cache.
config = BertConfig.from_pretrained(
"./test/saved_model/"
) # E.g. config (or model) was saved using *save_pretrained('./test/saved_model/')*
config = BertConfig.from_pretrained("./test/saved_model/my_configuration.json")
config = BertConfig.from_pretrained("bert-base-uncased", output_attentions=True, foo=False)
assert config.output_attentions == True
config, unused_kwargs = BertConfig.from_pretrained(
"bert-base-uncased", output_attentions=True, foo=False, return_unused_kwargs=True
)
assert config.output_attentions == True
assert unused_kwargs == {"foo": False}
```"""
kwargs["cache_dir"] = cache_dir
kwargs["force_download"] = force_download
kwargs["local_files_only"] = local_files_only
kwargs["revision"] = revision
cls._set_token_in_kwargs(kwargs, token)
config_dict, kwargs = cls.get_config_dict(pretrained_model_name_or_path, **kwargs)
if "model_type" in config_dict and hasattr(cls, "model_type") and config_dict["model_type"] != cls.model_type:
logger.warning(
f"You are using a model of type {config_dict['model_type']} to instantiate a model of type "
f"{cls.model_type}. This is not supported for all configurations of models and can yield errors."
)
return cls.from_dict(config_dict, **kwargs)
@classmethod
def get_config_dict(
cls, pretrained_model_name_or_path: Union[str, os.PathLike], **kwargs
) -> Tuple[Dict[str, Any], Dict[str, Any]]:
"""
From a `pretrained_model_name_or_path`, resolve to a dictionary of parameters, to be used for instantiating a
[`PretrainedConfig`] using `from_dict`.
Parameters:
pretrained_model_name_or_path (`str` or `os.PathLike`):
The identifier of the pre-trained checkpoint from which we want the dictionary of parameters.
Returns:
`Tuple[Dict, Dict]`: The dictionary(ies) that will be used to instantiate the configuration object.
"""
cls._set_token_in_kwargs(kwargs)
original_kwargs = copy.deepcopy(kwargs)
# Get config dict associated with the base config file
config_dict, kwargs = cls._get_config_dict(pretrained_model_name_or_path, **kwargs)
if "_commit_hash" in config_dict:
original_kwargs["_commit_hash"] = config_dict["_commit_hash"]
# That config file may point us toward another config file to use.
if "configuration_files" in config_dict:
configuration_file = get_configuration_file(config_dict["configuration_files"])
config_dict, kwargs = cls._get_config_dict(
pretrained_model_name_or_path, _configuration_file=configuration_file, **original_kwargs
)
return config_dict, kwargs
@classmethod
def _get_config_dict(
cls, pretrained_model_name_or_path: Union[str, os.PathLike], **kwargs
) -> Tuple[Dict[str, Any], Dict[str, Any]]:
cache_dir = kwargs.pop("cache_dir", None)
force_download = kwargs.pop("force_download", False)
resume_download = kwargs.pop("resume_download", False)
proxies = kwargs.pop("proxies", None)
token = kwargs.pop("token", None)
local_files_only = kwargs.pop("local_files_only", False)
revision = kwargs.pop("revision", None)
trust_remote_code = kwargs.pop("trust_remote_code", None)
subfolder = kwargs.pop("subfolder", "")
from_pipeline = kwargs.pop("_from_pipeline", None)
from_auto_class = kwargs.pop("_from_auto", False)
commit_hash = kwargs.pop("_commit_hash", None)
if trust_remote_code is True:
logger.warning(
"The argument `trust_remote_code` is to be used with Auto classes. It has no effect here and is"
" ignored."
)
user_agent = {"file_type": "config", "from_auto_class": from_auto_class}
if from_pipeline is not None:
user_agent["using_pipeline"] = from_pipeline
pretrained_model_name_or_path = str(pretrained_model_name_or_path)
is_local = os.path.isdir(pretrained_model_name_or_path)
if os.path.isfile(os.path.join(subfolder, pretrained_model_name_or_path)):
# Special case when pretrained_model_name_or_path is a local file
resolved_config_file = pretrained_model_name_or_path
is_local = True
elif is_remote_url(pretrained_model_name_or_path):
configuration_file = pretrained_model_name_or_path
resolved_config_file = download_url(pretrained_model_name_or_path)
else:
configuration_file = kwargs.pop("_configuration_file", CONFIG_NAME)
try:
# Load from local folder or from cache or download from model Hub and cache
resolved_config_file = cached_file(
pretrained_model_name_or_path,
configuration_file,
cache_dir=cache_dir,
force_download=force_download,
proxies=proxies,
resume_download=resume_download,
local_files_only=local_files_only,
token=token,
user_agent=user_agent,
revision=revision,
subfolder=subfolder,
_commit_hash=commit_hash,
)
commit_hash = extract_commit_hash(resolved_config_file, commit_hash)
except EnvironmentError:
# Raise any environment error raise by `cached_file`. It will have a helpful error message adapted to
# the original exception.
raise
except Exception:
# For any other exception, we throw a generic error.
raise EnvironmentError(
f"Can't load the configuration of '{pretrained_model_name_or_path}'. If you were trying to load it"
" from 'https://huggingface.co/models', make sure you don't have a local directory with the same"
f" name. Otherwise, make sure '{pretrained_model_name_or_path}' is the correct path to a directory"
f" containing a {configuration_file} file"
)
try:
# Load config dict
config_dict = cls._dict_from_json_file(resolved_config_file)
config_dict["_commit_hash"] = commit_hash
except (json.JSONDecodeError, UnicodeDecodeError):
raise EnvironmentError(
f"It looks like the config file at '{resolved_config_file}' is not a valid JSON file."
)
if is_local:
logger.info(f"loading configuration file {resolved_config_file}")
else:
logger.info(f"loading configuration file {configuration_file} from cache at {resolved_config_file}")
if "auto_map" in config_dict and not is_local:
config_dict["auto_map"] = add_model_info_to_auto_map(
config_dict["auto_map"], pretrained_model_name_or_path
)
return config_dict, kwargs
@classmethod
def from_dict(cls, config_dict: Dict[str, Any], **kwargs) -> "PretrainedConfig":
"""
Instantiates a [`PretrainedConfig`] from a Python dictionary of parameters.
Args:
config_dict (`Dict[str, Any]`):
Dictionary that will be used to instantiate the configuration object. Such a dictionary can be
retrieved from a pretrained checkpoint by leveraging the [`~PretrainedConfig.get_config_dict`] method.
kwargs (`Dict[str, Any]`):
Additional parameters from which to initialize the configuration object.
Returns:
[`PretrainedConfig`]: The configuration object instantiated from those parameters.
"""
return_unused_kwargs = kwargs.pop("return_unused_kwargs", False)
# Those arguments may be passed along for our internal telemetry.
# We remove them so they don't appear in `return_unused_kwargs`.
kwargs.pop("_from_auto", None)
kwargs.pop("_from_pipeline", None)
# The commit hash might have been updated in the `config_dict`, we don't want the kwargs to erase that update.
if "_commit_hash" in kwargs and "_commit_hash" in config_dict:
kwargs["_commit_hash"] = config_dict["_commit_hash"]
# We remove it from kwargs so that it does not appear in `return_unused_kwargs`.
config_dict["attn_implementation"] = kwargs.pop("attn_implementation", None)
config = cls(**config_dict)
if hasattr(config, "pruned_heads"):
config.pruned_heads = {int(key): value for key, value in config.pruned_heads.items()}
# Update config with kwargs if needed
if "num_labels" in kwargs and "id2label" in kwargs:
num_labels = kwargs["num_labels"]
id2label = kwargs["id2label"] if kwargs["id2label"] is not None else []
if len(id2label) != num_labels:
raise ValueError(
f"You passed along `num_labels={num_labels }` with an incompatible id to label map: "
f"{kwargs['id2label']}. Since those arguments are inconsistent with each other, you should remove "
"one of them."
)
to_remove = []
for key, value in kwargs.items():
if hasattr(config, key):
current_attr = getattr(config, key)
# To authorize passing a custom subconfig as kwarg in models that have nested configs.
if isinstance(current_attr, PretrainedConfig) and isinstance(value, dict):
value = current_attr.__class__(**value)
setattr(config, key, value)
if key != "torch_dtype":
to_remove.append(key)
for key in to_remove:
kwargs.pop(key, None)
logger.info(f"Model config {config}")
if return_unused_kwargs:
return config, kwargs
else:
return config
@classmethod
def from_json_file(cls, json_file: Union[str, os.PathLike]) -> "PretrainedConfig":
"""
Instantiates a [`PretrainedConfig`] from the path to a JSON file of parameters.
Args:
json_file (`str` or `os.PathLike`):
Path to the JSON file containing the parameters.
Returns:
[`PretrainedConfig`]: The configuration object instantiated from that JSON file.
"""
config_dict = cls._dict_from_json_file(json_file)
return cls(**config_dict)
@classmethod
def _dict_from_json_file(cls, json_file: Union[str, os.PathLike]):
with open(json_file, "r", encoding="utf-8") as reader:
text = reader.read()
return json.loads(text)
def __eq__(self, other):
return isinstance(other, PretrainedConfig) and (self.__dict__ == other.__dict__)
def __repr__(self):
return f"{self.__class__.__name__} {self.to_json_string()}"
def to_diff_dict(self) -> Dict[str, Any]:
"""
Removes all attributes from config which correspond to the default config attributes for better readability and
serializes to a Python dictionary.
Returns:
`Dict[str, Any]`: Dictionary of all the attributes that make up this configuration instance,
"""
config_dict = self.to_dict()
# get the default config dict
default_config_dict = PretrainedConfig().to_dict()
# get class specific config dict
class_config_dict = self.__class__().to_dict() if not self.is_composition else {}
serializable_config_dict = {}
# only serialize values that differ from the default config
for key, value in config_dict.items():
if (
isinstance(getattr(self, key, None), PretrainedConfig)
and key in class_config_dict
and isinstance(class_config_dict[key], dict)
):
# For nested configs we need to clean the diff recursively
diff = recursive_diff_dict(value, class_config_dict[key], config_obj=getattr(self, key, None))
if "model_type" in value:
# Needs to be set even if it's not in the diff
diff["model_type"] = value["model_type"]
if len(diff) > 0:
serializable_config_dict[key] = diff
elif (
key not in default_config_dict
or key == "transformers_version"
or value != default_config_dict[key]
or (key in class_config_dict and value != class_config_dict[key])
):
serializable_config_dict[key] = value
if hasattr(self, "quantization_config"):
serializable_config_dict["quantization_config"] = (
self.quantization_config.to_dict()
if not isinstance(self.quantization_config, dict)
else self.quantization_config
)
# pop the `_pre_quantization_dtype` as torch.dtypes are not serializable.
_ = serializable_config_dict.pop("_pre_quantization_dtype", None)
self.dict_torch_dtype_to_str(serializable_config_dict)
if "_attn_implementation_internal" in serializable_config_dict:
del serializable_config_dict["_attn_implementation_internal"]
return serializable_config_dict
def to_dict(self) -> Dict[str, Any]:
"""
Serializes this instance to a Python dictionary.
Returns:
`Dict[str, Any]`: Dictionary of all the attributes that make up this configuration instance.
"""
output = copy.deepcopy(self.__dict__)
if hasattr(self.__class__, "model_type"):
output["model_type"] = self.__class__.model_type
if "_auto_class" in output:
del output["_auto_class"]
if "_commit_hash" in output:
del output["_commit_hash"]
if "_attn_implementation_internal" in output:
del output["_attn_implementation_internal"]
# Transformers version when serializing the model
output["transformers_version"] = __version__
for key, value in output.items():
# Deal with nested configs like CLIP
if isinstance(value, PretrainedConfig):
value = value.to_dict()
del value["transformers_version"]
output[key] = value
if hasattr(self, "quantization_config"):
output["quantization_config"] = (
self.quantization_config.to_dict()
if not isinstance(self.quantization_config, dict)
else self.quantization_config
)
# pop the `_pre_quantization_dtype` as torch.dtypes are not serializable.
_ = output.pop("_pre_quantization_dtype", None)
self.dict_torch_dtype_to_str(output)
return output
def to_json_string(self, use_diff: bool = True) -> str:
"""
Serializes this instance to a JSON string.
Args:
use_diff (`bool`, *optional*, defaults to `True`):
If set to `True`, only the difference between the config instance and the default `PretrainedConfig()`
is serialized to JSON string.
Returns:
`str`: String containing all the attributes that make up this configuration instance in JSON format.
"""
if use_diff is True:
config_dict = self.to_diff_dict()
else:
config_dict = self.to_dict()
return json.dumps(config_dict, indent=2, sort_keys=True) + "\n"
def to_json_file(self, json_file_path: Union[str, os.PathLike], use_diff: bool = True):
"""
Save this instance to a JSON file.
Args:
json_file_path (`str` or `os.PathLike`):
Path to the JSON file in which this configuration instance's parameters will be saved.
use_diff (`bool`, *optional*, defaults to `True`):
If set to `True`, only the difference between the config instance and the default `PretrainedConfig()`
is serialized to JSON file.
"""
with open(json_file_path, "w", encoding="utf-8") as writer:
writer.write(self.to_json_string(use_diff=use_diff))
def update(self, config_dict: Dict[str, Any]):
"""
Updates attributes of this class with attributes from `config_dict`.
Args:
config_dict (`Dict[str, Any]`): Dictionary of attributes that should be updated for this class.
"""
for key, value in config_dict.items():
setattr(self, key, value)
def update_from_string(self, update_str: str):
"""
Updates attributes of this class with attributes from `update_str`.
The expected format is ints, floats and strings as is, and for booleans use `true` or `false`. For example:
"n_embd=10,resid_pdrop=0.2,scale_attn_weights=false,summary_type=cls_index"
The keys to change have to already exist in the config object.
Args:
update_str (`str`): String with attributes that should be updated for this class.
"""
d = dict(x.split("=") for x in update_str.split(","))
for k, v in d.items():
if not hasattr(self, k):
raise ValueError(f"key {k} isn't in the original config dict")
old_v = getattr(self, k)
if isinstance(old_v, bool):
if v.lower() in ["true", "1", "y", "yes"]:
v = True
elif v.lower() in ["false", "0", "n", "no"]:
v = False
else:
raise ValueError(f"can't derive true or false from {v} (key {k})")
elif isinstance(old_v, int):
v = int(v)
elif isinstance(old_v, float):
v = float(v)
elif not isinstance(old_v, str):
raise ValueError(
f"You can only update int, float, bool or string values in the config, got {v} for key {k}"
)
setattr(self, k, v)
def dict_torch_dtype_to_str(self, d: Dict[str, Any]) -> None:
"""
Checks whether the passed dictionary and its nested dicts have a *torch_dtype* key and if it's not None,
converts torch.dtype to a string of just the type. For example, `torch.float32` get converted into *"float32"*
string, which can then be stored in the json format.
"""
if d.get("torch_dtype", None) is not None and not isinstance(d["torch_dtype"], str):
d["torch_dtype"] = str(d["torch_dtype"]).split(".")[1]
for value in d.values():
if isinstance(value, dict):
self.dict_torch_dtype_to_str(value)
@classmethod
def register_for_auto_class(cls, auto_class="AutoConfig"):
"""
Register this class with a given auto class. This should only be used for custom configurations as the ones in
the library are already mapped with `AutoConfig`.
This API is experimental and may have some slight breaking changes in the next releases.
Args:
auto_class (`str` or `type`, *optional*, defaults to `"AutoConfig"`):
The auto class to register this new configuration with.
"""
if not isinstance(auto_class, str):
auto_class = auto_class.__name__
import transformers.models.auto as auto_module
if not hasattr(auto_module, auto_class):
raise ValueError(f"{auto_class} is not a valid auto class.")
cls._auto_class = auto_class
def get_configuration_file(configuration_files: List[str]) -> str:
"""
Get the configuration file to use for this version of transformers.
Args:
configuration_files (`List[str]`): The list of available configuration files.
Returns:
`str`: The configuration file to use.
"""
configuration_files_map = {}
for file_name in configuration_files:
search = _re_configuration_file.search(file_name)
if search is not None:
v = search.groups()[0]
configuration_files_map[v] = file_name
available_versions = sorted(configuration_files_map.keys())
# Defaults to FULL_CONFIGURATION_FILE and then try to look at some newer versions.
configuration_file = CONFIG_NAME
transformers_version = version.parse(__version__)
for v in available_versions:
if version.parse(v) <= transformers_version:
configuration_file = configuration_files_map[v]
else:
# No point going further since the versions are sorted.
break
return configuration_file
def recursive_diff_dict(dict_a, dict_b, config_obj=None):
"""
Helper function to recursively take the diff between two nested dictionaries. The resulting diff only contains the
values from `dict_a` that are different from values in `dict_b`.
"""
diff = {}
default = config_obj.__class__().to_dict() if config_obj is not None else {}
for key, value in dict_a.items():
obj_value = getattr(config_obj, str(key), None)
if isinstance(obj_value, PretrainedConfig) and key in dict_b and isinstance(dict_b[key], dict):
diff_value = recursive_diff_dict(value, dict_b[key], config_obj=obj_value)
if len(diff_value) > 0:
diff[key] = diff_value
elif key not in dict_b or value != dict_b[key] or key not in default or value != default[key]:
diff[key] = value
return diff
PretrainedConfig.push_to_hub = copy_func(PretrainedConfig.push_to_hub)
if PretrainedConfig.push_to_hub.__doc__ is not None:
PretrainedConfig.push_to_hub.__doc__ = PretrainedConfig.push_to_hub.__doc__.format(
object="config", object_class="AutoConfig", object_files="configuration file"
)