| """Small JSON object extraction helpers for model output.""" |
|
|
| from __future__ import annotations |
|
|
| import json |
| from typing import Any |
|
|
|
|
| def parse_json_object(raw: str) -> dict[str, Any]: |
| value = json.loads(_extract_json_object(raw)) |
| if not isinstance(value, dict): |
| raise ValueError("Expected a JSON object.") |
| return value |
|
|
|
|
| def _extract_json_object(raw: str) -> str: |
| clean = _strip_markdown_fence(raw.strip()) |
|
|
| candidate = _scan_json_object(clean) |
| if candidate is None: |
| raise ValueError("No JSON object found.") |
| return candidate |
|
|
|
|
| def _strip_markdown_fence(clean: str) -> str: |
| if not clean.startswith("```"): |
| return clean |
|
|
| lines = clean.splitlines() |
| if not lines: |
| return clean |
|
|
| if lines[0].strip().startswith("```"): |
| lines = lines[1:] |
| if lines and lines[-1].strip().startswith("```"): |
| lines = lines[:-1] |
| return "\n".join(lines).strip() |
|
|
|
|
| def _scan_json_object(clean: str) -> str | None: |
| start = clean.find("{") |
| if start == -1: |
| return None |
|
|
| stack: list[str] = [] |
| in_string = False |
| escaped = False |
|
|
| for index, char in enumerate(clean[start:], start=start): |
| if in_string: |
| if escaped: |
| escaped = False |
| elif char == "\\": |
| escaped = True |
| elif char == '"': |
| in_string = False |
| continue |
|
|
| if char == '"': |
| in_string = True |
| elif char == "{": |
| stack.append("}") |
| elif char == "[": |
| stack.append("]") |
| elif char in {"}", "]"}: |
| if not stack or stack[-1] != char: |
| return None |
| stack.pop() |
| if not stack: |
| return clean[start : index + 1] |
|
|
| if in_string or not stack: |
| return None |
| return clean[start:] + "".join(reversed(stack)) |
|
|
