import base64 import json import os from io import BytesIO from typing import Any, Dict, List, Literal, Optional, Union import requests import torch from PIL import Image from torch import nn from transformers import AutoConfig, AutoImageProcessor, AutoModel, AutoTokenizer class Transformer(nn.Module): """Huggingface AutoModel to generate token embeddings. Loads the correct class, e.g. BERT / RoBERTa etc. Args: model_name_or_path: Huggingface models name (https://huggingface.co/models) max_seq_length: Truncate any inputs longer than max_seq_length model_args: Keyword arguments passed to the Huggingface Transformers model tokenizer_args: Keyword arguments passed to the Huggingface Transformers tokenizer config_args: Keyword arguments passed to the Huggingface Transformers config cache_dir: Cache dir for Huggingface Transformers to store/load models do_lower_case: If true, lowercases the input (independent if the model is cased or not) tokenizer_name_or_path: Name or path of the tokenizer. When None, then model_name_or_path is used """ def __init__( self, model_name_or_path: str, max_seq_length: Optional[int] = None, model_args: Optional[Dict[str, Any]] = None, tokenizer_args: Optional[Dict[str, Any]] = None, config_args: Optional[Dict[str, Any]] = None, cache_dir: Optional[str] = None, do_lower_case: bool = False, tokenizer_name_or_path: str = None, backend: Literal['torch', 'onnx', 'openvino'] = 'torch', **_, ) -> None: super(Transformer, self).__init__() if backend != 'torch': raise ValueError( f'Backend \'{backend}\' is not supported, please use \'torch\' instead' ) self.config_keys = ["max_seq_length", "do_lower_case"] self.do_lower_case = do_lower_case if model_args is None: model_args = {} if tokenizer_args is None: tokenizer_args = {} if config_args is None: config_args = {} config = AutoConfig.from_pretrained( model_name_or_path, **config_args, cache_dir=cache_dir ) self.jina_clip = AutoModel.from_pretrained( model_name_or_path, config=config, cache_dir=cache_dir, **model_args ) if max_seq_length is not None and "model_max_length" not in tokenizer_args: tokenizer_args["model_max_length"] = max_seq_length self.tokenizer = AutoTokenizer.from_pretrained( ( tokenizer_name_or_path if tokenizer_name_or_path is not None else model_name_or_path ), cache_dir=cache_dir, **tokenizer_args, ) self.preprocessor = AutoImageProcessor.from_pretrained( ( tokenizer_name_or_path if tokenizer_name_or_path is not None else model_name_or_path ), cache_dir=cache_dir, **tokenizer_args, ) # No max_seq_length set. Try to infer from model if max_seq_length is None: if ( hasattr(self.jina_clip, "config") and hasattr(self.jina_clip.config, "max_position_embeddings") and hasattr(self.tokenizer, "model_max_length") ): max_seq_length = min( self.jina_clip.config.max_position_embeddings, self.tokenizer.model_max_length, ) self.max_seq_length = max_seq_length if tokenizer_name_or_path is not None: self.jina_clip.config.tokenizer_class = self.tokenizer.__class__.__name__ def forward( self, features: Dict[str, torch.Tensor] ) -> Dict[str, torch.Tensor]: """Returns token_embeddings, cls_token""" if "input_ids" in features: embedding = self.jina_clip.get_text_features( input_ids=features["input_ids"] ) else: embedding = self.jina_clip.get_image_features( pixel_values=features["pixel_values"] ) return {"sentence_embedding": embedding} def get_word_embedding_dimension(self) -> int: return self.config.text_config.embed_dim def decode_data_image(data_image_str): header, data = data_image_str.split(',', 1) image_data = base64.b64decode(data) return Image.open(BytesIO(image_data)) def tokenize( self, batch: Union[List[str]], padding: Union[str, bool] = True ) -> Dict[str, torch.Tensor]: """Tokenizes a text and maps tokens to token-ids""" images = [] texts = [] for sample in batch: if isinstance(sample, str): if sample.startswith('http'): response = requests.get(sample) images.append(Image.open(BytesIO(response.content)).convert('RGB')) elif sample.startswith('data:image/'): images.append(self.decode_data_image(sample).convert('RGB')) else: # TODO: Make sure that Image.open fails for non-image files try: images.append(Image.open(sample).convert('RGB')) except: texts.append(sample) elif isinstance(sample, Image.Image): images.append(sample.convert('RGB')) if images and texts: raise ValueError('Batch must contain either images or texts, not both') if texts: return self.tokenizer( texts, padding=padding, truncation="longest_first", return_tensors="pt", max_length=self.max_seq_length, ) elif images: return self.preprocessor(images) return {} def save(self, output_path: str, safe_serialization: bool = True) -> None: self.jina_clip.save_pretrained( output_path, safe_serialization=safe_serialization ) self.tokenizer.save_pretrained(output_path) self.preprocessor.save_pretrained(output_path) @staticmethod def load(input_path: str) -> "Transformer": # Old classes used other config names than 'sentence_bert_config.json' for config_name in [ "sentence_bert_config.json", "sentence_roberta_config.json", "sentence_distilbert_config.json", "sentence_camembert_config.json", "sentence_albert_config.json", "sentence_xlm-roberta_config.json", "sentence_xlnet_config.json", ]: sbert_config_path = os.path.join(input_path, config_name) if os.path.exists(sbert_config_path): break with open(sbert_config_path) as fIn: config = json.load(fIn) # Don't allow configs to set trust_remote_code if "model_args" in config and "trust_remote_code" in config["model_args"]: config["model_args"].pop("trust_remote_code") if ( "tokenizer_args" in config and "trust_remote_code" in config["tokenizer_args"] ): config["tokenizer_args"].pop("trust_remote_code") if "config_args" in config and "trust_remote_code" in config["config_args"]: config["config_args"].pop("trust_remote_code") return Transformer(model_name_or_path=input_path, **config)