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f8dbde1 | 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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 | """Light, safe normalization of real-world JSON Schemas into deg-compilable ones.
Used for external schema sources (JSONSchemaBench for datagen, ExtractBench for eval). The
result is a self-contained schema that :func:`deg.schema.compile_schema` accepts, or
``None`` with a reason. Only lossless-or-annotation edits and *dropping whole fields* are
done; a field's meaning is never rewritten:
- local ``$ref`` is inlined (recursive refs drop the referring field), ``$defs`` removed;
- annotation-like and unsupported validation keywords are dropped (``examples``, vendor
``x-*``/custom keys, ``minProperties``, ``dependencies``, ``contentEncoding``, ...);
- ``format`` values deg does not parse are dropped (the field becomes a plain span);
- ``allOf`` with non-conflicting branches is merged; nullable objects/arrays lose ``null``;
- a plain ``anyOf`` of string and number types becomes a string span (nullable if listed);
- a missing ``type`` is inferred from ``properties``/``items``/``enum`` when unambiguous;
- fields that still cannot compile (``const``, free-form maps, tuple arrays, multi-type
unions, non-enum ``anyOf``) are dropped, from ``required`` too;
- the tree is capped at ``max_leaves`` leaves and ``max_depth`` nesting (later properties
are dropped first).
The compiler is the judge: after the rewrite, every field named in a compile error is
dropped and the schema recompiled until it compiles or nothing fillable is left.
"""
from __future__ import annotations
import copy
from typing import Any
from deg.schema import ANNOTATIONS, TYPE_KEYWORDS, SchemaError, compile_schema
FORMATS = {"date", "date-time", "email", "uri", "uuid"}
KEEP_ANNOTATIONS = {"title", "description"}
_VALIDATION = frozenset().union(*TYPE_KEYWORDS.values()) | {
"enum", "const", "anyOf", "oneOf", "allOf", "not", "$ref"}
class Skip(ValueError):
"""The schema (or a subtree) cannot be normalized; ``reason`` is machine-readable."""
def __init__(self, reason: str) -> None:
super().__init__(reason)
self.reason = reason
def _resolve_ref(root: Any, ref: str) -> Any:
if not isinstance(ref, str) or not (ref == "#" or ref.startswith("#/")):
raise Skip("nonlocal_ref")
target = root
for raw in ref[2:].split("/") if ref != "#" else []:
part = raw.replace("~1", "/").replace("~0", "~")
if isinstance(target, dict) and part in target:
target = target[part]
elif isinstance(target, list) and part.isdigit() and int(part) < len(target):
target = target[int(part)]
else:
raise Skip("unresolvable_ref")
if not isinstance(target, dict):
raise Skip("bad_ref")
return target
class _Normalizer:
def __init__(self, root: dict[str, Any], max_depth: int) -> None:
self.root = root
self.max_depth = max_depth
def inline(self, s: Any, refs: tuple[str, ...]) -> tuple[dict[str, Any], tuple[str, ...]]:
while isinstance(s, dict) and "$ref" in s:
ref = s["$ref"]
if ref in refs:
raise Skip("recursive_ref")
target = _resolve_ref(self.root, ref)
s = {**target, **{k: v for k, v in s.items() if k != "$ref"}}
refs = (*refs, ref)
if not isinstance(s, dict):
raise Skip("boolean_schema")
return s, refs
def merge_all_of(self, s: dict[str, Any], refs: tuple[str, ...]) -> dict[str, Any]:
out = {k: v for k, v in s.items() if k != "allOf"}
for branch in s["allOf"] if isinstance(s["allOf"], list) else []:
try:
b, _ = self.inline(branch, refs)
except Skip as exc:
if exc.reason == "nonlocal_ref": # an external base type: keep the rest
continue
raise
if "allOf" in b:
b = self.merge_all_of(b, refs)
for k, v in b.items():
if k == "properties" and isinstance(v, dict):
out["properties"] = {**out.get("properties", {}), **v}
elif k == "required" and isinstance(v, list):
out["required"] = list(dict.fromkeys([*out.get("required", []), *v]))
elif k in out and out[k] != v and k not in ANNOTATIONS:
raise Skip("allOf_conflict")
else:
out.setdefault(k, v)
return out
def node(self, raw: Any, refs: tuple[str, ...], depth: int) -> dict[str, Any]:
s, refs = self.inline(raw, refs)
if "allOf" in s:
s = self.merge_all_of(s, refs)
if "const" in s:
raise Skip("const")
for key in ("anyOf", "oneOf"):
if key in s:
return self.union(s, key, refs, depth)
t = s.get("type")
if t is None:
if "properties" in s:
t = "object"
elif "items" in s:
t = "array"
elif isinstance(s.get("enum"), list) and s["enum"]:
kinds = {_kind(v) for v in s["enum"] if v is not None}
if len(kinds) != 1:
raise Skip("untyped_enum")
t = kinds.pop()
else:
raise Skip("untyped")
nullable = False
if isinstance(t, list):
non_null = [x for x in t if x != "null"]
if len(non_null) != 1:
raise Skip("multi_type")
nullable = "null" in t
t = non_null[0]
if t not in TYPE_KEYWORDS:
raise Skip(f"type_{t}")
out: dict[str, Any] = {k: v for k, v in s.items()
if k in KEEP_ANNOTATIONS and isinstance(v, str)}
if "enum" in s:
if not isinstance(s["enum"], list):
raise Skip("bad_enum")
values = list(dict.fromkeys(_freeze(v) for v in s["enum"]))
values = [_thaw(v) for v in values]
if len([v for v in values if v is not None]) < 2 or len(values) > 255:
raise Skip("enum_size")
out["enum"] = values
for k in TYPE_KEYWORDS[t]:
if k in s and k not in ("properties", "items", "required", "additionalProperties"):
if "enum" in out and t in ("string", "integer", "number"):
continue # the enum already pins the value; bounds/lengths are redundant
out[k] = s[k]
if t == "string" and out.get("format") not in FORMATS:
out.pop("format", None)
if t == "object":
if depth >= self.max_depth:
raise Skip("too_deep")
props = s.get("properties")
if not isinstance(props, dict) or not props:
raise Skip("free_form_object")
req = s.get("required") if isinstance(s.get("required"), list) else []
kept: dict[str, Any] = {}
for name, sub in props.items():
try:
kept[name] = self.node(sub, refs, depth + 1)
except Skip:
continue
if not kept:
raise Skip("no_fillable_properties")
out["properties"] = kept
required = [r for r in req if r in kept]
if required:
out["required"] = required
out["additionalProperties"] = False
out["type"] = "object" # nullable objects are not supported: drop null
return out
if t == "array":
items = s.get("items")
if not isinstance(items, dict):
raise Skip("tuple_or_untyped_array")
out["items"] = self.node(items, refs, depth + 1)
if out["items"].get("type") == "array":
raise Skip("nested_array")
out["type"] = "array"
return out
if nullable and "enum" in out and None not in out["enum"]:
out["enum"] = [*out["enum"], None]
nullable = nullable or None in out.get("enum", [])
out["type"] = [t, "null"] if nullable else t
return out
def union(self, s: dict[str, Any], key: str, refs: tuple[str, ...],
depth: int) -> dict[str, Any]:
branches = s[key] if isinstance(s[key], list) else []
resolved = [self.inline(b, refs)[0] for b in branches]
nulls = [b for b in resolved if b.get("type") == "null"]
others = [b for b in resolved if b.get("type") != "null"]
ann = {k: v for k, v in s.items() if k in KEEP_ANNOTATIONS and isinstance(v, str)}
if len(others) == 1: # nullable form (or a 1-branch union)
inner = self.node({**others[0], **ann}, refs, depth)
if nulls and inner.get("type") not in ("object", "array"):
if "enum" in inner and None not in inner["enum"]:
inner["enum"] = [*inner["enum"], None]
if isinstance(inner.get("type"), str):
inner["type"] = [inner["type"], "null"]
return inner
types = {b.get("type") if isinstance(b.get("type"), str) else "?" for b in resolved}
plain = not any(set(b) & _VALIDATION for b in resolved) # only type + annotations
if plain and "string" in types and types <= {"string", "integer", "number", "null"}:
# "a string or a number": the value is copied from text either way -> a span
return self.node({**ann, "type": ["string", "null"] if nulls else "string"},
refs, depth)
values: list[Any] = []
for b in resolved:
if "const" in b:
values.append(b["const"])
elif isinstance(b.get("enum"), list):
values.extend(b["enum"])
elif b.get("type") == "null":
values.append(None)
else:
raise Skip("union")
return self.node({**ann, "enum": values}, refs, depth)
def _kind(v: Any) -> str:
if isinstance(v, bool):
return "boolean"
if isinstance(v, int):
return "integer"
if isinstance(v, float):
return "number"
if isinstance(v, str):
return "string"
return "object"
def _freeze(v: Any) -> Any:
return ("__json__", repr(v)) if isinstance(v, (dict, list)) else (type(v).__name__, v)
def _thaw(v: Any) -> Any:
if v[0] == "__json__":
raise Skip("structured_enum")
return v[1]
def count_leaves(s: dict[str, Any]) -> int:
if s.get("type") == "object":
return sum(count_leaves(p) for p in s["properties"].values())
if s.get("type") == "array":
return count_leaves(s["items"])
return 1
def cap_leaves(s: dict[str, Any], budget: int) -> int:
"""Keep properties in order while they fit ``budget`` leaves; returns leaves kept."""
if s.get("type") == "array":
return cap_leaves(s["items"], budget)
if s.get("type") != "object":
return 1
used = 0
kept: dict[str, Any] = {}
for name, sub in s["properties"].items():
if used >= budget:
break
n = count_leaves(sub)
if n > budget - used:
if sub.get("type") in ("object", "array") and budget - used >= 2:
n = cap_leaves(sub, budget - used)
else:
continue
kept[name] = sub
used += n
s["properties"] = kept
if "required" in s:
s["required"] = [r for r in s["required"] if r in kept]
if not s["required"]:
del s["required"]
return used
def _drop_at(schema: dict[str, Any], loc: list[Any]) -> bool:
"""Drop the deepest property named in an error ``loc``; False if none can be dropped."""
if loc and loc[0] == "schema": # compiler locs are rooted at "schema"
loc = loc[1:]
cuts = [i for i in range(len(loc) - 1) if loc[i] == "properties"]
for i in reversed(cuts):
parent: Any = schema
try:
for part in loc[:i]:
parent = parent[part]
except (KeyError, IndexError, TypeError):
continue
name = loc[i + 1]
props = parent.get("properties") if isinstance(parent, dict) else None
if isinstance(props, dict) and name in props and len(props) > 1:
del props[name]
if name in parent.get("required", []):
parent["required"] = [r for r in parent["required"] if r != name]
if not parent["required"]:
del parent["required"]
return True
return False
def normalize_schema(schema: Any, max_leaves: int = 30, max_depth: int = 5,
min_leaves: int = 2) -> tuple[dict[str, Any] | None, str]:
"""(deg-compilable schema, "ok") or (None, skip reason)."""
if not isinstance(schema, dict):
return None, "not_object"
root = copy.deepcopy(schema)
try:
out = _Normalizer(root, max_depth).node(root, ("#",), 0)
except Skip as exc:
return None, exc.reason
except RecursionError:
return None, "recursion"
if out.get("type") != "object":
return None, "root_not_object"
cap_leaves(out, max_leaves)
for _ in range(64):
try:
compile_schema(out)
break
except SchemaError as exc:
if not any(_drop_at(out, e["loc"]) for e in exc.errors[:1]):
return None, "compile:" + exc.errors[0]["msg"][:60]
else:
return None, "compile_loop"
if count_leaves(out) < min_leaves:
return None, "too_few_leaves"
return out, "ok"
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