#!/usr/bin/env python3
from __future__ import annotations
import argparse
import itertools
import json
import re
import sys
from typing import Any, List, Optional, Set, Tuple, Union
def _build_repetition(item_rule, min_items, max_items, separator_rule=None):
if max_items == 0:
return ""
if min_items == 0 and max_items == 1:
return f'{item_rule}?'
if not separator_rule:
if min_items == 1 and max_items is None:
return f'{item_rule}+'
elif min_items == 0 and max_items is None:
return f'{item_rule}*'
else:
return f'{item_rule}{{{min_items},{max_items if max_items is not None else ""}}}'
result = item_rule + ' ' + _build_repetition(f'({separator_rule} {item_rule})', min_items - 1 if min_items > 0 else 0, max_items - 1 if max_items is not None else None)
return f'({result})?' if min_items == 0 else result
def _generate_min_max_int(min_value: Optional[int], max_value: Optional[int], out: list, decimals_left: int = 16, top_level: bool = True):
def digit_range(from_char: str, to_char: str):
out.append("[")
if from_char == to_char:
out.append(from_char)
else:
out.append(from_char)
out.append("-")
out.append(to_char)
out.append("]")
def more_digits(min_digits: int, max_digits: int):
out.append("[0-9]")
if min_digits == max_digits and min_digits == 1:
return
out.append("{")
out.append(str(min_digits))
if max_digits != min_digits:
out.append(",")
if max_digits != sys.maxsize:
out.append(str(max_digits))
out.append("}")
def uniform_range(from_str: str, to_str: str):
i = 0
while i < len(from_str) and from_str[i] == to_str[i]:
i += 1
if i > 0:
out.append("\"")
out.append(from_str[:i])
out.append("\"")
if i < len(from_str):
if i > 0:
out.append(" ")
sub_len = len(from_str) - i - 1
if sub_len > 0:
from_sub = from_str[i+1:]
to_sub = to_str[i+1:]
sub_zeros = "0" * sub_len
sub_nines = "9" * sub_len
to_reached = False
out.append("(")
if from_sub == sub_zeros:
digit_range(from_str[i], chr(ord(to_str[i]) - 1))
out.append(" ")
more_digits(sub_len, sub_len)
else:
out.append("[")
out.append(from_str[i])
out.append("] ")
out.append("(")
uniform_range(from_sub, sub_nines)
out.append(")")
if ord(from_str[i]) < ord(to_str[i]) - 1:
out.append(" | ")
if to_sub == sub_nines:
digit_range(chr(ord(from_str[i]) + 1), to_str[i])
to_reached = True
else:
digit_range(chr(ord(from_str[i]) + 1), chr(ord(to_str[i]) - 1))
out.append(" ")
more_digits(sub_len, sub_len)
if not to_reached:
out.append(" | ")
digit_range(to_str[i], to_str[i])
out.append(" ")
uniform_range(sub_zeros, to_sub)
out.append(")")
else:
out.append("[")
out.append(from_str[i])
out.append("-")
out.append(to_str[i])
out.append("]")
if min_value is not None and max_value is not None:
if min_value < 0 and max_value < 0:
out.append("\"-\" (")
_generate_min_max_int(-max_value, -min_value, out, decimals_left, top_level=True)
out.append(")")
return
if min_value < 0:
out.append("\"-\" (")
_generate_min_max_int(0, -min_value, out, decimals_left, top_level=True)
out.append(") | ")
min_value = 0
min_s = str(min_value)
max_s = str(max_value)
min_digits = len(min_s)
max_digits = len(max_s)
for digits in range(min_digits, max_digits):
uniform_range(min_s, "9" * digits)
min_s = "1" + "0" * digits
out.append(" | ")
uniform_range(min_s, max_s)
return
less_decimals = max(decimals_left - 1, 1)
if min_value is not None:
if min_value < 0:
out.append("\"-\" (")
_generate_min_max_int(None, -min_value, out, decimals_left, top_level=False)
out.append(") | [0] | [1-9] ")
more_digits(0, decimals_left - 1)
elif min_value == 0:
if top_level:
out.append("[0] | [1-9] ")
more_digits(0, less_decimals)
else:
more_digits(1, decimals_left)
elif min_value <= 9:
c = str(min_value)
range_start = '1' if top_level else '0'
if c > range_start:
digit_range(range_start, chr(ord(c) - 1))
out.append(" ")
more_digits(1, less_decimals)
out.append(" | ")
digit_range(c, "9")
out.append(" ")
more_digits(0, less_decimals)
else:
min_s = str(min_value)
length = len(min_s)
c = min_s[0]
if c > "1":
digit_range("1" if top_level else "0", chr(ord(c) - 1))
out.append(" ")
more_digits(length, less_decimals)
out.append(" | ")
digit_range(c, c)
out.append(" (")
_generate_min_max_int(int(min_s[1:]), None, out, less_decimals, top_level=False)
out.append(")")
if c < "9":
out.append(" | ")
digit_range(chr(ord(c) + 1), "9")
out.append(" ")
more_digits(length - 1, less_decimals)
return
if max_value is not None:
if max_value >= 0:
if top_level:
out.append("\"-\" [1-9] ")
more_digits(0, less_decimals)
out.append(" | ")
_generate_min_max_int(0, max_value, out, decimals_left, top_level=True)
else:
out.append("\"-\" (")
_generate_min_max_int(-max_value, None, out, decimals_left, top_level=False)
out.append(")")
return
raise RuntimeError("At least one of min_value or max_value must be set")
class BuiltinRule:
def __init__(self, content: str, deps: list | None = None):
self.content = content
self.deps = deps or []
# Constraining spaces to prevent model "running away".
SPACE_RULE = '| " " | "\\n"{1,2} [ \\t]{0,20}'
PRIMITIVE_RULES = {
'boolean' : BuiltinRule('("true" | "false")', []),
'decimal-part' : BuiltinRule('[0-9]{1,16}', []),
'integral-part': BuiltinRule('[0] | [1-9] [0-9]{0,15}', []),
'number' : BuiltinRule('("-"? integral-part) ("." decimal-part)? ([eE] [-+]? integral-part)?', ['integral-part', 'decimal-part']),
'integer' : BuiltinRule('("-"? integral-part)', ['integral-part']),
'value' : BuiltinRule('object | array | string | number | boolean | null', ['object', 'array', 'string', 'number', 'boolean', 'null']),
'object' : BuiltinRule('"{" space ( string ":" space value ("," space string ":" space value)* )? space "}"', ['string', 'value']),
'array' : BuiltinRule('"[" space ( value ("," space value)* )? space "]"', ['value']),
'uuid' : BuiltinRule(r'"\"" [0-9a-fA-F]{8} "-" [0-9a-fA-F]{4} "-" [0-9a-fA-F]{4} "-" [0-9a-fA-F]{4} "-" [0-9a-fA-F]{12} "\""', []),
'char' : BuiltinRule(r'[^"\\\x7F\x00-\x1F] | [\\] (["\\bfnrt] | "u" [0-9a-fA-F]{4})', []),
'string' : BuiltinRule(r'"\"" char* "\""', ['char']),
'null' : BuiltinRule('"null"', []),
}
# TODO: support "uri", "email" string formats
STRING_FORMAT_RULES = {
'date' : BuiltinRule('[0-9]{4} "-" ( "0" [1-9] | "1" [0-2] ) "-" ( \"0\" [1-9] | [1-2] [0-9] | "3" [0-1] )', []),
'time' : BuiltinRule('([01] [0-9] | "2" [0-3]) ":" [0-5] [0-9] ":" [0-5] [0-9] ( "." [0-9]{3} )? ( "Z" | ( "+" | "-" ) ( [01] [0-9] | "2" [0-3] ) ":" [0-5] [0-9] )', []),
'date-time' : BuiltinRule('date "T" time', ['date', 'time']),
'date-string' : BuiltinRule('"\\"" date "\\""', ['date']),
'time-string' : BuiltinRule('"\\"" time "\\""', ['time']),
'date-time-string': BuiltinRule('"\\"" date-time "\\""', ['date-time']),
}
DOTALL = '[\\U00000000-\\U0010FFFF]'
DOT = '[^\\x0A\\x0D]'
RESERVED_NAMES = set(["root", "dot", *PRIMITIVE_RULES.keys(), *STRING_FORMAT_RULES.keys()])
INVALID_RULE_CHARS_RE = re.compile(r'[^a-zA-Z0-9-]+')
GRAMMAR_LITERAL_ESCAPE_RE = re.compile(r'[\r\n"\\]')
GRAMMAR_RANGE_LITERAL_ESCAPE_RE = re.compile(r'[\r\n"\]\-\\]')
GRAMMAR_LITERAL_ESCAPES = {'\r': '\\r', '\n': '\\n', '"': '\\"', '-': '\\-', ']': '\\]', '\\': '\\\\'}
NON_LITERAL_SET = set('|.()[]{}*+?')
ESCAPED_IN_REGEXPS_BUT_NOT_IN_LITERALS = set('^$.[]()|{}*+?')
class SchemaConverter:
def __init__(self, *, prop_order, allow_fetch, dotall, raw_pattern):
self._prop_order = prop_order
self._allow_fetch = allow_fetch
self._dotall = dotall
self._raw_pattern = raw_pattern
self._rules = {
'space': SPACE_RULE,
}
self._refs = {}
self._refs_being_resolved = set()
def _format_literal(self, literal):
escaped = GRAMMAR_LITERAL_ESCAPE_RE.sub(
lambda m: GRAMMAR_LITERAL_ESCAPES.get(m.group(0)) or m.group(0), literal
)
return f'"{escaped}"'
def not_literal(self, literal: str, dotall: bool = True, maybe_escaped_underscores = False) -> str:
'''
not_literal('a') -> '[^a]'
not_literal('abc') -> '([^a] | "a" ([^b] | "b" ([^c])?)?)?'
'''
assert len(literal) > 0, 'Empty literal not supported'
def recurse(i: int):
c = literal[i]
if maybe_escaped_underscores and c == '_':
yield f'[^{c}\\\\]'
yield ' | '
yield f'"\\\\"? "{c}"'
else:
yield f'[^{c}]'
if i < len(literal) - 1:
yield ' | '
yield self._format_literal(c)
yield ' ('
yield from recurse(i + 1)
yield ')?'
return ''.join(('(', *recurse(0), ')'))
def _not_strings(self, strings):
class TrieNode:
def __init__(self):
self.children = {}
self.is_end_of_string = False
def insert(self, string):
node = self
for c in string:
node = node.children.setdefault(c, TrieNode())
node.is_end_of_string = True
trie = TrieNode()
for s in strings:
trie.insert(s)
char_rule = self._add_primitive('char', PRIMITIVE_RULES['char'])
out = ['["] ( ']
def visit(node):
rejects = []
first = True
for c in sorted(node.children.keys()):
child = node.children[c]
rejects.append(c)
if first:
first = False
else:
out.append(' | ')
out.append(f'[{c}]')
if child.children:
out.append(f' (')
visit(child)
out.append(')')
elif child.is_end_of_string:
out.append(f' {char_rule}+')
if node.children:
if not first:
out.append(' | ')
out.append(f'[^"{"".join(rejects)}] {char_rule}*')
visit(trie)
out.append(f' ){"" if trie.is_end_of_string else "?"} ["]')
return ''.join(out)
def _add_rule(self, name, rule):
esc_name = INVALID_RULE_CHARS_RE.sub('-', name)
if esc_name not in self._rules or self._rules[esc_name] == rule:
key = esc_name
else:
i = 0
while f'{esc_name}{i}' in self._rules and self._rules[f'{esc_name}{i}'] != rule:
i += 1
key = f'{esc_name}{i}'
self._rules[key] = rule
return key
def resolve_refs(self, schema: dict, url: str):
'''
Resolves all $ref fields in the given schema, fetching any remote schemas,
replacing $ref with absolute reference URL and populating self._refs with the
respective referenced (sub)schema dictionaries.
'''
def visit(n: dict):
if isinstance(n, list):
return [visit(x) for x in n]
elif isinstance(n, dict):
ref = n.get('$ref')
if ref is not None and ref not in self._refs:
if ref.startswith('https://'):
assert self._allow_fetch, 'Fetching remote schemas is not allowed (use --allow-fetch for force)'
import requests
frag_split = ref.split('#')
base_url = frag_split[0]
target = self._refs.get(base_url)
if target is None:
target = self.resolve_refs(requests.get(ref).json(), base_url)
self._refs[base_url] = target
if len(frag_split) == 1 or frag_split[-1] == '':
return target
elif ref.startswith('#/'):
target = schema
ref = f'{url}{ref}'
n['$ref'] = ref
else:
raise ValueError(f'Unsupported ref {ref}')
for sel in ref.split('#')[-1].split('/')[1:]:
assert target is not None, f'Error resolving ref {ref}: {sel} not in {target}'
if isinstance(target, list):
try:
sel_index = int(sel)
except ValueError:
raise ValueError(f'Error resolving ref {ref}: {sel} not in {target}')
assert 0 <= sel_index < len(target), f'Error resolving ref {ref}: {sel} not in {target}'
target = target[sel_index]
else:
assert sel in target, f'Error resolving ref {ref}: {sel} not in {target}'
target = target[sel]
self._refs[ref] = target
else:
for v in n.values():
visit(v)
return n
return visit(schema)
def _generate_union_rule(self, name, alt_schemas):
return ' | '.join((
self.visit(alt_schema, f'{name}{"-" if name else "alternative-"}{i}')
for i, alt_schema in enumerate(alt_schemas)
))
def _visit_pattern(self, pattern, name):
'''
Transforms a regular expression pattern into a GBNF rule.
Input: https://json-schema.org/understanding-json-schema/reference/regular_expressions
Output: https://github.com/ggml-org/llama.cpp/blob/master/grammars/README.md
Unsupported features: negative/positive lookaheads, greedy/non-greedy modifiers.
Mostly a 1:1 translation, except for {x} / {x,} / {x,y} quantifiers for which
we define sub-rules to keep the output lean.
'''
assert pattern.startswith('^') and pattern.endswith('$'), 'Pattern must start with "^" and end with "$"'
pattern = pattern[1:-1]
sub_rule_ids = {}
i = 0
length = len(pattern)
def to_rule(s: tuple[str, bool]) -> str:
(txt, is_literal) = s
return "\"" + txt + "\"" if is_literal else txt
def transform() -> tuple[str, bool]:
'''
Parse a unit at index i (advancing it), and return its string representation + whether it's a literal.
'''
nonlocal i
nonlocal pattern
nonlocal sub_rule_ids
start = i
# For each component of this sequence, store its string representation and whether it's a literal.
# We only need a flat structure here to apply repetition operators to the last item, and
# to merge literals at the and (we're parsing grouped ( sequences ) recursively and don't treat '|' specially
# (GBNF's syntax is luckily very close to regular expressions!)
seq: list[tuple[str, bool]] = []
def get_dot():
if self._dotall:
rule = DOTALL
else:
# Accept any character... except \n and \r line break chars (\x0A and \xOD)
rule = DOT
return self._add_rule(f'dot', rule)
def join_seq():
nonlocal seq
ret = []
for is_literal, g in itertools.groupby(seq, lambda x: x[1]):
if is_literal:
ret.append((''.join(x[0] for x in g), True))
else:
ret.extend(g)
if len(ret) == 1:
return ret[0]
return (' '.join(to_rule(x) for x in seq), False)
while i < length:
c = pattern[i]
if c == '.':
seq.append((get_dot(), False))
i += 1
elif c == '(':
i += 1
if i < length:
assert pattern[i] != '?', f'Unsupported pattern syntax "{pattern[i]}" at index {i} of /{pattern}/'
seq.append((f'({to_rule(transform())})', False))
elif c == ')':
i += 1
assert start > 0 and pattern[start-1] == '(', f'Unbalanced parentheses; start = {start}, i = {i}, pattern = {pattern}'
return join_seq()
elif c == '[':
square_brackets = c
i += 1
while i < length and pattern[i] != ']':
if pattern[i] == '\\':
square_brackets += pattern[i:i+2]
i += 2
else:
square_brackets += pattern[i]
i += 1
assert i < length, f'Unbalanced square brackets; start = {start}, i = {i}, pattern = {pattern}'
square_brackets += ']'
i += 1
seq.append((square_brackets, False))
elif c == '|':
seq.append(('|', False))
i += 1
elif c in ('*', '+', '?'):
seq[-1] = (to_rule(seq[-1]) + c, False)
i += 1
elif c == '{':
curly_brackets = c
i += 1
while i < length and pattern[i] != '}':
curly_brackets += pattern[i]
i += 1
assert i < length, f'Unbalanced curly brackets; start = {start}, i = {i}, pattern = {pattern}'
curly_brackets += '}'
i += 1
nums = [s.strip() for s in curly_brackets[1:-1].split(',')]
min_times = 0
max_times = None
try:
if len(nums) == 1:
min_times = int(nums[0])
max_times = min_times
else:
assert len(nums) == 2
min_times = int(nums[0]) if nums[0] else 0
max_times = int(nums[1]) if nums[1] else None
except ValueError:
raise ValueError(f'Invalid quantifier {curly_brackets} in /{pattern}/')
(sub, sub_is_literal) = seq[-1]
if not sub_is_literal:
id = sub_rule_ids.get(sub)
if id is None:
id = self._add_rule(f'{name}-{len(sub_rule_ids) + 1}', sub)
sub_rule_ids[sub] = id
sub = id
seq[-1] = (_build_repetition(f'"{sub}"' if sub_is_literal else sub, min_times, max_times), False)
else:
literal = ''
while i < length:
if pattern[i] == '\\' and i < length - 1:
next = pattern[i + 1]
if next in ESCAPED_IN_REGEXPS_BUT_NOT_IN_LITERALS:
i += 1
literal += pattern[i]
i += 1
else:
literal += pattern[i:i+2]
i += 2
elif pattern[i] == '"' and not self._raw_pattern:
literal += '\\"'
i += 1
elif pattern[i] not in NON_LITERAL_SET and \
(i == length - 1 or literal == '' or pattern[i+1] == '.' or pattern[i+1] not in NON_LITERAL_SET):
literal += pattern[i]
i += 1
else:
break
if literal:
seq.append((literal, True))
return join_seq()
return self._add_rule(
name,
to_rule(transform()) if self._raw_pattern \
else "\"\\\"\" (" + to_rule(transform()) + ") \"\\\"\"")
def _resolve_ref(self, ref):
ref_fragment = ref.split('#')[-1]
ref_name = 'ref' + re.sub(r'[^a-zA-Z0-9-]+', '-', ref_fragment)
if ref_name not in self._rules and ref not in self._refs_being_resolved:
self._refs_being_resolved.add(ref)
resolved = self._refs[ref]
ref_name = self.visit(resolved, ref_name)
self._refs_being_resolved.remove(ref)
return ref_name
def _generate_constant_rule(self, value):
return self._format_literal(json.dumps(value))
def visit(self, schema, name):
schema_type = schema.get('type')
schema_format = schema.get('format')
rule_name = name + '-' if name in RESERVED_NAMES else name or 'root'
if (ref := schema.get('$ref')) is not None:
return self._add_rule(rule_name, self._resolve_ref(ref))
elif 'oneOf' in schema or 'anyOf' in schema:
return self._add_rule(rule_name, self._generate_union_rule(name, schema.get('oneOf') or schema['anyOf']))
elif isinstance(schema_type, list):
return self._add_rule(rule_name, self._generate_union_rule(name, [{**schema, 'type': t} for t in schema_type]))
elif 'const' in schema:
return self._add_rule(rule_name, self._generate_constant_rule(schema['const']))
elif 'enum' in schema:
rule = '(' + ' | '.join((self._generate_constant_rule(v) for v in schema['enum'])) + ')'
return self._add_rule(rule_name, rule)
elif schema_type in (None, 'object') and \
('properties' in schema or \
('additionalProperties' in schema and schema['additionalProperties'] is not True)):
required = set(schema.get('required', []))
properties = list(schema.get('properties', {}).items())
return self._add_rule(rule_name, self._build_object_rule(properties, required, name, schema.get('additionalProperties')))
elif schema_type in (None, 'object', 'string') and 'allOf' in schema:
required = set()
properties = []
enum_sets = []
hybrid_name = name
def add_component(comp_schema, is_required):
if (ref := comp_schema.get('$ref')) is not None:
comp_schema = self._refs[ref]
if 'properties' in comp_schema:
for prop_name, prop_schema in comp_schema['properties'].items():
properties.append((prop_name, prop_schema))
if is_required:
required.add(prop_name)
if 'enum' in comp_schema:
enum_sets.append(set(comp_schema['enum']))
for t in schema['allOf']:
if 'anyOf' in t:
for tt in t['anyOf']:
add_component(tt, is_required=False)
else:
add_component(t, is_required=True)
if enum_sets:
enum_intersection = enum_sets[0]
for s in enum_sets[1:]:
enum_intersection &= s
if enum_intersection:
rule = '(' + ' | '.join((self._generate_constant_rule(v) for v in sorted(enum_intersection))) + ')'
return self._add_rule(rule_name, rule)
return self._add_rule(rule_name, self._build_object_rule(properties, required, hybrid_name, additional_properties=None))
elif schema_type in (None, 'array') and ('items' in schema or 'prefixItems' in schema):
items = schema.get('items', schema.get('prefixItems'))
if isinstance(items, list):
return self._add_rule(
rule_name,
'"[" space ' +
' "," space '.join(
self.visit(item, f'{name}{"-" if name else ""}tuple-{i}')
for i, item in enumerate(items)) +
' space "]"')
else:
item_rule_name = self.visit(items, f'{name}{"-" if name else ""}item')
min_items = schema.get("minItems", 0)
max_items = schema.get("maxItems")
return self._add_rule(rule_name, '"[" space ' + _build_repetition(item_rule_name, min_items, max_items, separator_rule='"," space') + ' space "]"')
elif schema_type in (None, 'string') and 'pattern' in schema:
return self._visit_pattern(schema['pattern'], rule_name)
elif schema_type in (None, 'string') and re.match(r'^uuid[1-5]?$', schema_format or ''):
return self._add_primitive(
'root' if rule_name == 'root' else schema_format,
PRIMITIVE_RULES['uuid']
)
elif schema_type in (None, 'string') and f'{schema_format}-string' in STRING_FORMAT_RULES:
prim_name = f'{schema_format}-string'
return self._add_rule(rule_name, self._add_primitive(prim_name, STRING_FORMAT_RULES[prim_name]))
elif schema_type == 'string' and ('minLength' in schema or 'maxLength' in schema):
char_rule = self._add_primitive('char', PRIMITIVE_RULES['char'])
min_len = schema.get('minLength', 0)
max_len = schema.get('maxLength')
return self._add_rule(rule_name, r'"\"" ' + _build_repetition(char_rule, min_len, max_len) + r' "\""')
elif schema_type in (None, 'integer') and \
('minimum' in schema or 'exclusiveMinimum' in schema or 'maximum' in schema or 'exclusiveMaximum' in schema):
min_value = None
max_value = None
if 'minimum' in schema:
min_value = schema['minimum']
elif 'exclusiveMinimum' in schema:
min_value = schema['exclusiveMinimum'] + 1
if 'maximum' in schema:
max_value = schema['maximum']
elif 'exclusiveMaximum' in schema:
max_value = schema['exclusiveMaximum'] - 1
out = ["("]
_generate_min_max_int(min_value, max_value, out)
out.append(")")
return self._add_rule(rule_name, ''.join(out))
elif (schema_type == 'object') or (len(schema) == 0):
return self._add_rule(rule_name, self._add_primitive('object', PRIMITIVE_RULES['object']))
elif schema_type is None and isinstance(schema, dict):
# No type constraint and no recognized structural keywords (e.g. {"description": "..."}).
# Per JSON Schema semantics this is equivalent to {} and accepts any value.
return self._add_rule(rule_name, self._add_primitive('value', PRIMITIVE_RULES['value']))
else:
assert schema_type in PRIMITIVE_RULES, f'Unrecognized schema: {schema}'
# TODO: support minimum, maximum, exclusiveMinimum, exclusiveMaximum at least for zero
return self._add_primitive('root' if rule_name == 'root' else schema_type, PRIMITIVE_RULES[schema_type])
def _add_primitive(self, name: str, rule: BuiltinRule):
n = self._add_rule(name, rule.content)
for dep in rule.deps:
dep_rule = PRIMITIVE_RULES.get(dep) or STRING_FORMAT_RULES.get(dep)
assert dep_rule, f'Rule {dep} not known'
if dep not in self._rules:
self._add_primitive(dep, dep_rule)
return n
def _build_object_rule(self, properties: List[Tuple[str, Any]], required: Set[str], name: str, additional_properties: Optional[Union[bool, Any]]):
prop_order = self._prop_order
# sort by position in prop_order (if specified) then by original order
sorted_props = [kv[0] for _, kv in sorted(enumerate(properties), key=lambda ikv: (prop_order.get(ikv[1][0], len(prop_order)), ikv[0]))]
prop_kv_rule_names = {}
for prop_name, prop_schema in properties:
prop_rule_name = self.visit(prop_schema, f'{name}{"-" if name else ""}{prop_name}')
prop_kv_rule_names[prop_name] = self._add_rule(
f'{name}{"-" if name else ""}{prop_name}-kv',
fr'{self._format_literal(json.dumps(prop_name))} space ":" space {prop_rule_name}'
)
required_props = [k for k in sorted_props if k in required]
optional_props = [k for k in sorted_props if k not in required]
if additional_properties is not None and additional_properties != False:
sub_name = f'{name}{"-" if name else ""}additional'
value_rule = self.visit(additional_properties, f'{sub_name}-value') if isinstance(additional_properties, dict) else \
self._add_primitive('value', PRIMITIVE_RULES['value'])
key_rule = self._add_primitive('string', PRIMITIVE_RULES['string']) if not sorted_props \
else self._add_rule(f'{sub_name}-k', self._not_strings(sorted_props))
prop_kv_rule_names["*"] = self._add_rule(
f'{sub_name}-kv',
f'{key_rule} ":" space {value_rule}'
)
optional_props.append("*")
rule = '"{" space '
rule += ' "," space '.join(prop_kv_rule_names[k] for k in required_props)
if optional_props:
rule += ' ('
if required_props:
rule += ' "," space ( '
def get_recursive_refs(ks, first_is_optional):
[k, *rest] = ks
kv_rule_name = prop_kv_rule_names[k]
comma_ref = f'( "," space {kv_rule_name} )'
if first_is_optional:
res = comma_ref + ('*' if k == '*' else '?')
else:
res = kv_rule_name + (' ' + comma_ref + "*" if k == '*' else '')
if len(rest) > 0:
res += ' ' + self._add_rule(
f'{name}{"-" if name else ""}{k}-rest',
get_recursive_refs(rest, first_is_optional=True)
)
return res
rule += ' | '.join(
get_recursive_refs(optional_props[i:], first_is_optional=False)
for i in range(len(optional_props))
)
if required_props:
rule += ' )'
rule += ' )?'
rule += ' space "}"'
return rule
def format_grammar(self):
return '\n'.join(
f'{name} ::= {rule}'
for name, rule in sorted(self._rules.items(), key=lambda kv: kv[0])
)
def main(args_in = None):
parser = argparse.ArgumentParser(
description='''
Generates a grammar (suitable for use in ./llama-cli) that produces JSON conforming to a
given JSON schema. Only a subset of JSON schema features are supported; more may be
added in the future.
''',
)
parser.add_argument(
'--prop-order',
default=[],
type=lambda s: s.split(','),
help='''
comma-separated property names defining the order of precedence for object properties;
properties not specified here are given lower precedence than those that are, and
are kept in their original order from the schema. Required properties are always
given precedence over optional properties.
'''
)
parser.add_argument(
'--allow-fetch',
action='store_true',
default=False,
help='Whether to allow fetching referenced schemas over HTTPS')
parser.add_argument(
'--dotall',
action='store_true',
default=False,
help='Whether to treat dot (".") as matching all chars including line breaks in regular expression patterns')
parser.add_argument(
'--raw-pattern',
action='store_true',
default=False,
help='Treats string patterns as raw patterns w/o quotes (or quote escapes)')
parser.add_argument('schema', help='file containing JSON schema ("-" for stdin)')
args = parser.parse_args(args_in)
if args.schema.startswith('https://'):
url = args.schema
import requests
schema = requests.get(url).json()
elif args.schema == '-':
url = 'stdin'
schema = json.load(sys.stdin)
else:
url = f'file://{args.schema}'
with open(args.schema) as f:
schema = json.load(f)
converter = SchemaConverter(
prop_order={name: idx for idx, name in enumerate(args.prop_order)},
allow_fetch=args.allow_fetch,
dotall=args.dotall,
raw_pattern=args.raw_pattern)
schema = converter.resolve_refs(schema, url)
converter.visit(schema, '')
print(converter.format_grammar())
if __name__ == '__main__':
main()