Skip to content

vllm.entrypoints.openai.tool_parsers.utils

consume_space 

consume_space(i: int, s: str) -> int
Source code in vllm/entrypoints/openai/tool_parsers/utils.py 
121
122
123
124
def consume_space(i: int, s: str) -> int:
    while i < len(s) and s[i].isspace():
        i += 1
    return i

extract_intermediate_diff 

extract_intermediate_diff(curr: str, old: str) -> str

Given two strings, extract the difference in the middle between two strings that are known to have a common prefix and/or suffix.

This function is provided as a UTILITY for extracting information from JSON generated by partial_json_parser, to help in ensuring that the right tokens are returned in streaming, so that close-quotes, close-brackets and close-braces are not returned prematurely. The order of arguments IS important - the new version of the partially-parsed JSON must be the first argument, and the secnod argument must be from the previous generation.

What it returns, is tokens that should be streamed to the client.

e.g. extract_intermediate_diff('{"fruit": "apple"}', '{"fruit": "ap"}') -> 'ple'

Source code in vllm/entrypoints/openai/tool_parsers/utils.py 
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
def extract_intermediate_diff(curr: str, old: str) -> str:
    """
    Given two strings, extract the difference in the middle between two strings
    that are known to have a common prefix and/or suffix.

    This function is provided as a UTILITY for extracting information from JSON
    generated by partial_json_parser, to help in ensuring that the right tokens
    are returned in streaming, so that close-quotes, close-brackets and
    close-braces are not returned prematurely. The order of arguments IS
    important - the new version of the partially-parsed JSON must be the first
    argument, and the secnod argument must be from the previous generation.

    What it returns, is tokens that should be streamed to the client.

    e.g. extract_intermediate_diff('{"fruit": "apple"}', '{"fruit": "ap"}')
        -> 'ple'

    """
    suffix = find_common_suffix(curr, old)

    old = old[::-1].replace(suffix[::-1], '', 1)[::-1]
    prefix = find_common_prefix(curr, old)
    diff = curr
    if len(suffix):
        diff = diff[::-1].replace(suffix[::-1], '', 1)[::-1]

    if len(prefix):
        # replace the prefix only once in case it's mirrored
        diff = diff.replace(prefix, '', 1)

    return diff

find_all_indices 

find_all_indices(string: str, substring: str) -> list[int]

Find all (starting) indices of a substring in a given string. Useful for tool call extraction

Source code in vllm/entrypoints/openai/tool_parsers/utils.py 
86
87
88
89
90
91
92
93
94
95
96
97
98
def find_all_indices(string: str, substring: str) -> list[int]:
    """
    Find all (starting) indices of a substring in a given string. Useful for
    tool call extraction
    """
    indices = []
    index = -1
    while True:
        index = string.find(substring, index + 1)
        if index == -1:
            break
        indices.append(index)
    return indices

find_common_prefix 

find_common_prefix(s1: str, s2: str) -> str

Finds a common prefix that is shared between two strings, if there is one. Order of arguments is NOT important.

This function is provided as a UTILITY for extracting information from JSON generated by partial_json_parser, to help in ensuring that the right tokens are returned in streaming, so that close-quotes, close-brackets and close-braces are not returned prematurely.

e.g. find_common_prefix('{"fruit": "ap"}', '{"fruit": "apple"}') -> '{"fruit": "ap'

Source code in vllm/entrypoints/openai/tool_parsers/utils.py 
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
def find_common_prefix(s1: str, s2: str) -> str:
    """
    Finds a common prefix that is shared between two strings, if there is one.
    Order of arguments is NOT important.

    This function is provided as a UTILITY for extracting information from JSON
    generated by partial_json_parser, to help in ensuring that the right tokens
    are returned in streaming, so that close-quotes, close-brackets and
    close-braces are not returned prematurely.

    e.g. find_common_prefix('{"fruit": "ap"}', '{"fruit": "apple"}') ->
    '{"fruit": "ap'
    """
    prefix = ''
    min_length = min(len(s1), len(s2))
    for i in range(0, min_length):
        if s1[i] == s2[i]:
            prefix += s1[i]
        else:
            break
    return prefix

find_common_suffix 

find_common_suffix(s1: str, s2: str) -> str

Finds a common suffix shared between two strings, if there is one. Order of arguments is NOT important. Stops when the suffix ends OR it hits an alphanumeric character

e.g. find_common_suffix('{"fruit": "ap"}', '{"fruit": "apple"}') -> '"}'

Source code in vllm/entrypoints/openai/tool_parsers/utils.py 
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
def find_common_suffix(s1: str, s2: str) -> str:
    """
    Finds a common suffix shared between two strings, if there is one. Order of
    arguments is NOT important.
    Stops when the suffix ends OR it hits an alphanumeric character

    e.g. find_common_suffix('{"fruit": "ap"}', '{"fruit": "apple"}') -> '"}'
    """
    suffix = ''
    min_length = min(len(s1), len(s2))
    for i in range(1, min_length + 1):
        if s1[-i] == s2[-i] and not s1[-i].isalnum():
            suffix = s1[-i] + suffix
        else:
            break
    return suffix

is_complete_json 

is_complete_json(input_str: str) -> bool
Source code in vllm/entrypoints/openai/tool_parsers/utils.py 
113
114
115
116
117
118
def is_complete_json(input_str: str) -> bool:
    try:
        json.loads(input_str)
        return True
    except JSONDecodeError:
        return False

partial_json_loads 

partial_json_loads(
    input_str: str, flags: Allow
) -> tuple[Any, int]
Source code in vllm/entrypoints/openai/tool_parsers/utils.py 
103
104
105
106
107
108
109
110
def partial_json_loads(input_str: str, flags: Allow) -> tuple[Any, int]:
    try:
        return (partial_json_parser.loads(input_str, flags), len(input_str))
    except JSONDecodeError as e:
        if "Extra data" in e.msg:
            dec = JSONDecoder()
            return dec.raw_decode(input_str)
        raise