from torch.utils.data import DataLoader
import math
from sentence_transformers import SentenceTransformer,  LoggingHandler, losses, models, util
from sentence_transformers.evaluation import EmbeddingSimilarityEvaluator
from sentence_transformers.readers import InputExample
import logging
from datetime import datetime
import sys
import os
import gzip
import csv

#### Just some code to print debug information to stdout
只是一些将调试信息打印到标准输出的代码

logging.basicConfig(format=‘%(asctime)s - %(message)s‘,
                    datefmt=‘%Y-%m-%d %H:%M:%S‘,
                    level=logging.INFO,
                    handlers=[LoggingHandler()])
#### /print debug information to stdout 调试信息打印到标准输出



#Check if dataset exsist. If not, download and extract  it  检查数据集是否存在。 如果没有，请下载并解压
sts_dataset_path = ‘datasets/stsbenchmark.tsv.gz‘

if not os.path.exists(sts_dataset_path):
    util.http_get(‘https://sbert.net/datasets/stsbenchmark.tsv.gz‘, sts_dataset_path)



#You can specify any huggingface/transformers pre-trained model here, for example, bert-base-uncased, roberta-base, xlm-roberta-base
您可以在此处指定任何 Huggingface/transformers 预训练模型，例如，bert-base-uncased、roberta-base、xlm-roberta-base

model_name = sys.argv[1] if len(sys.argv) > 1 else ‘distilbert-base-uncased‘

# Read the dataset 读取数据集
train_batch_size = 16
num_epochs = 4
model_save_path = ‘output/training_stsbenchmark_‘+model_name.replace("/", "-")+‘-‘+datetime.now().strftime("%Y-%m-%d_%H-%M-%S")

# Use Huggingface/transformers model (like BERT, RoBERTa, XLNet, XLM-R) for mapping tokens to embeddings
使用 Huggingface/transformers 模型（如 BERT、RoBERTa、XLNet、XLM-R）将令牌映射到嵌入

word_embedding_model = models.Transformer(model_name)

# Apply mean pooling to get one fixed sized sentence vector 应用平均池化得到一个固定大小的句子向量
pooling_model = models.Pooling(word_embedding_model.get_word_embedding_dimension(),
                               pooling_mode_mean_tokens=True,
                               pooling_mode_cls_token=False,
                               pooling_mode_max_tokens=False)

model = SentenceTransformer(modules=[word_embedding_model, pooling_model])

# Convert the dataset to a DataLoader ready for training 将数据集转换为准备训练的 DataLoader
logging.info("Read STSbenchmark train dataset")

train_samples = []
dev_samples = []
test_samples = []
with gzip.open(sts_dataset_path, ‘rt‘, encoding=‘utf8‘) as fIn:
    reader = csv.DictReader(fIn, delimiter=‘\t‘, quoting=csv.QUOTE_NONE)
    for row in reader:
        score = float(row[‘score‘]) / 5.0  # Normalize score to range 0 ... 1
        inp_example = InputExample(texts=[row[‘sentence1‘], row[‘sentence2‘]], label=score)

        if row[‘split‘] == ‘dev‘:
            dev_samples.append(inp_example)
        elif row[‘split‘] == ‘test‘:
            test_samples.append(inp_example)
        else:
            train_samples.append(inp_example)


train_dataloader = DataLoader(train_samples, shuffle=True, batch_size=train_batch_size)
train_loss = losses.CosineSimilarityLoss(model=model)


logging.info("Read STSbenchmark dev dataset")
evaluator = EmbeddingSimilarityEvaluator.from_input_examples(dev_samples, name=‘sts-dev‘)


# Configure the training. We skip evaluation in this example 配置训练。 我们在这个例子中跳过评估
warmup_steps = math.ceil(len(train_dataloader) * num_epochs  * 0.1) #10% of train data for warm-up
logging.info("Warmup-steps: {}".format(warmup_steps))


# Train the model
model.fit(train_objectives=[(train_dataloader, train_loss)],
          evaluator=evaluator,
          epochs=num_epochs,
          evaluation_steps=1000,
          warmup_steps=warmup_steps,
          output_path=model_save_path)


##############################################################################
#
# Load the stored model and evaluate its performance on STS benchmark dataset 加载存储的模型并评估其在 STS 基准数据集上的性能
#
##############################################################################

model = SentenceTransformer(model_save_path)
test_evaluator = EmbeddingSimilarityEvaluator.from_input_examples(test_samples, name=‘sts-test‘)
test_evaluator(model, output_path=model_save_path)

"""
This examples loads a pre-trained model and evaluates it on the STSbenchmark dataset
此示例加载预训练模型并在 STSbenchmark 数据集上对其进行评估
Usage:
python evaluation_stsbenchmark.py
OR
python evaluation_stsbenchmark.py model_name
"""
from sentence_transformers import SentenceTransformer,  util, LoggingHandler, InputExample
from sentence_transformers.evaluation import EmbeddingSimilarityEvaluator
import logging
import sys
import torch
import gzip
import os
import csv

script_folder_path = os.path.dirname(os.path.realpath(__file__))

#Limit torch to 4 threads 将割炬限制为 4 个线程
torch.set_num_threads(4)

#### Just some code to print debug information to stdout
logging.basicConfig(format=‘%(asctime)s - %(message)s‘,
                    datefmt=‘%Y-%m-%d %H:%M:%S‘,
                    level=logging.INFO,
                    handlers=[LoggingHandler()])
#### /print debug information to stdout

model_name = sys.argv[1] if len(sys.argv) > 1 else ‘stsb-distilroberta-base-v2‘

# Load a named sentence model (based on BERT). This will download the model from our server.
# Alternatively, you can also pass a filepath to SentenceTransformer()
加载命名句子模型（基于 BERT）。 这将从我们的服务器下载模型。 或者，您也可以将文件路径传递给 SentenceTransformer()

model = SentenceTransformer(model_name)


sts_dataset_path = ‘data/stsbenchmark.tsv.gz‘

if not os.path.exists(sts_dataset_path):
    util.http_get(‘https://sbert.net/datasets/stsbenchmark.tsv.gz‘, sts_dataset_path)

train_samples = []
dev_samples = []
test_samples = []
with gzip.open(sts_dataset_path, ‘rt‘, encoding=‘utf8‘) as fIn:
    reader = csv.DictReader(fIn, delimiter=‘\t‘, quoting=csv.QUOTE_NONE)
    for row in reader:
        score = float(row[‘score‘]) / 5.0  # Normalize score to range 0 ... 1
        inp_example = InputExample(texts=[row[‘sentence1‘], row[‘sentence2‘]], label=score)

        if row[‘split‘] == ‘dev‘:
            dev_samples.append(inp_example)
        elif row[‘split‘] == ‘test‘:
            test_samples.append(inp_example)
        else:
            train_samples.append(inp_example)

evaluator = EmbeddingSimilarityEvaluator.from_input_examples(dev_samples, name=‘sts-dev‘)
model.evaluate(evaluator)

evaluator = EmbeddingSimilarityEvaluator.from_input_examples(test_samples, name=‘sts-test‘)
model.evaluate(evaluator)