File size: 5,444 Bytes
bcdf9fa
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
# Copyright 2024 Bytedance Ltd. and/or its affiliates
#
# 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.

import os
from typing import List, Union

import pandas as pd
import torch
from torch.utils.data import Dataset

from verl.utils import hf_tokenizer


def download_files_distributed(download_fn):
    import torch.distributed

    if torch.distributed.is_initialized():
        if torch.distributed.get_rank() == 0:
            # download files
            download_fn()

        torch.distributed.barrier()
    else:
        # download anyway
        download_fn()


class RMDataset(Dataset):
    def __init__(

        self,

        parquet_files: Union[str, List[str]],

        tokenizer,

        prompt_key="prompt",

        chosen_key="chosen",

        rejected_key="rejected",

        max_length=1024,

        add_eos=True,

        cache_dir="~/.cache/verl/rm",

    ):
        if not isinstance(parquet_files, List):
            parquet_files = [parquet_files]

        self.parquet_files = parquet_files
        self.cache_dir = os.path.expanduser(cache_dir)
        if isinstance(tokenizer, str):
            tokenizer = hf_tokenizer(tokenizer)
        self.tokenizer = tokenizer

        self.prompt_key = prompt_key
        self.chosen_key = chosen_key
        self.rejected_key = rejected_key

        self.add_eos = add_eos
        self.max_length = max_length

        self._download()
        self._read_files_and_tokenize()

    def _download(self):
        def _download_files():
            from verl.utils.fs import copy, is_non_local

            os.makedirs(self.cache_dir, exist_ok=True)
            assert os.path.exists(self.cache_dir)
            for i, parquet_file in enumerate(self.parquet_files):
                if is_non_local(parquet_file):
                    dst = os.path.join(self.cache_dir, os.path.basename(parquet_file))
                    if not os.path.exists(dst):
                        copy(src=parquet_file, dst=dst)
                    self.parquet_files[i] = dst

        download_files_distributed(_download_files)

    def _read_files_and_tokenize(self):
        dataframes = []
        for parquet_file in self.parquet_files:
            # read parquet files and cache
            dataframe = pd.read_parquet(parquet_file)
            dataframes.append(dataframe)
        self.dataframe = pd.concat(dataframes)
        self.prompts = self.dataframe[self.prompt_key].tolist()
        self.chosen_responses = self.dataframe[self.chosen_key].tolist()
        self.rejected_responses = self.dataframe[self.rejected_key].tolist()

    def __len__(self):
        return len(self.prompts)

    def _pad_to_length(self, input_ids, attention_mask):
        curr_length = input_ids.shape[-1]

        if curr_length < self.max_length:
            input_ids = torch.cat((input_ids, torch.zeros(size=(self.max_length - curr_length,), dtype=input_ids.dtype)), dim=-1)
            attention_mask = torch.cat((attention_mask, torch.zeros(size=(self.max_length - curr_length,), dtype=attention_mask.dtype)), dim=-1)
        elif curr_length > self.max_length:
            input_ids = input_ids[: self.max_length]
            attention_mask = attention_mask[: self.max_length]

        return input_ids, attention_mask

    def __getitem__(self, item):
        prompt = self.prompts[item]
        chosen_response = self.chosen_responses[item]
        rejected_response = self.rejected_responses[item]

        prompt_ids = self.tokenizer(prompt, return_tensors="pt")["input_ids"][0]
        chosen_response_ids = self.tokenizer(chosen_response, return_tensors="pt")["input_ids"][0]
        rejected_response_ids = self.tokenizer(rejected_response, return_tensors="pt")["input_ids"][0]

        if self.add_eos:
            chosen_response_ids = torch.cat((chosen_response_ids, torch.tensor([self.tokenizer.eos_token_id])), dim=-1)
            rejected_response_ids = torch.cat((rejected_response_ids, torch.tensor([self.tokenizer.eos_token_id])), dim=-1)

        chosen_input_ids = torch.cat((prompt_ids, chosen_response_ids), dim=-1)
        chosen_attention_mask = torch.ones_like(chosen_input_ids)

        rejected_input_ids = torch.cat((prompt_ids, rejected_response_ids), dim=-1)
        rejected_attention_mask = torch.ones_like(rejected_input_ids)

        chosen_input_ids, chosen_attention_mask = self._pad_to_length(chosen_input_ids, chosen_attention_mask)
        rejected_input_ids, rejected_attention_mask = self._pad_to_length(rejected_input_ids, rejected_attention_mask)

        input_ids = torch.stack((chosen_input_ids, rejected_input_ids), dim=0)
        attention_mask = torch.stack((chosen_attention_mask, rejected_attention_mask), dim=0)

        return {
            "input_ids": input_ids,
            "attention_mask": attention_mask,
        }