fix(storage): harden sql persistence compatibility

backend/packages/storage/store/persistence/json_compat.py

@@ -0,0 +1,192 @@
+"""Dialect-aware JSON value matching for storage SQLAlchemy repositories."""
+
+from __future__ import annotations
+
+import re
+from dataclasses import dataclass
+from typing import Any
+
+from sqlalchemy import BigInteger, Float, String, bindparam
+from sqlalchemy.ext.compiler import compiles
+from sqlalchemy.sql.compiler import SQLCompiler
+from sqlalchemy.sql.expression import ColumnElement
+from sqlalchemy.sql.visitors import InternalTraversal
+from sqlalchemy.types import Boolean, TypeEngine
+
+_KEY_CHARSET_RE = re.compile(r"^[A-Za-z0-9_\-]+$")
+ALLOWED_FILTER_VALUE_TYPES: tuple[type, ...] = (type(None), bool, int, float, str)
+
+_INT64_MIN = -(2**63)
+_INT64_MAX = 2**63 - 1
+
+
+def validate_metadata_filter_key(key: object) -> bool:
+    """Return True when *key* is safe for JSON metadata filter SQL paths."""
+    return isinstance(key, str) and bool(_KEY_CHARSET_RE.match(key))
+
+
+def validate_metadata_filter_value(value: object) -> bool:
+    """Return True when *value* can be compiled into a portable JSON predicate."""
+    if not isinstance(value, ALLOWED_FILTER_VALUE_TYPES):
+        return False
+    if isinstance(value, int) and not isinstance(value, bool):
+        return _INT64_MIN <= value <= _INT64_MAX
+    return True
+
+
+class JsonMatch(ColumnElement[bool]):
+    """Dialect-portable ``column[key] == value`` for JSON columns."""
+
+    inherit_cache = True
+    type = Boolean()
+    _is_implicitly_boolean = True
+
+    _traverse_internals = [
+        ("column", InternalTraversal.dp_clauseelement),
+        ("key", InternalTraversal.dp_string),
+        ("value", InternalTraversal.dp_plain_obj),
+        ("value_type", InternalTraversal.dp_string),
+    ]
+
+    def __init__(self, column: ColumnElement[Any], key: str, value: object) -> None:
+        if not validate_metadata_filter_key(key):
+            raise ValueError(f"JsonMatch key must match {_KEY_CHARSET_RE.pattern!r}; got: {key!r}")
+        if not validate_metadata_filter_value(value):
+            if isinstance(value, int) and not isinstance(value, bool):
+                raise TypeError(f"JsonMatch int value out of signed 64-bit range [-2**63, 2**63-1]: {value!r}")
+            raise TypeError(f"JsonMatch value must be None, bool, int, float, or str; got: {type(value).__name__!r}")
+        self.column = column
+        self.key = key
+        self.value = value
+        self.value_type = type(value).__qualname__
+        super().__init__()
+
+
+@dataclass(frozen=True)
+class _Dialect:
+    null_type: str
+    num_types: tuple[str, ...]
+    num_cast: str
+    int_types: tuple[str, ...]
+    int_cast: str
+    int_guard: str | None
+    string_type: str
+    bool_type: str | None
+    true_value: str
+    false_value: str
+
+
+_SQLITE = _Dialect(
+    null_type="null",
+    num_types=("integer", "real"),
+    num_cast="REAL",
+    int_types=("integer",),
+    int_cast="INTEGER",
+    int_guard=None,
+    string_type="text",
+    bool_type=None,
+    true_value="true",
+    false_value="false",
+)
+
+_POSTGRES = _Dialect(
+    null_type="null",
+    num_types=("number",),
+    num_cast="DOUBLE PRECISION",
+    int_types=("number",),
+    int_cast="BIGINT",
+    int_guard="'^-?[0-9]+$'",
+    string_type="string",
+    bool_type="boolean",
+    true_value="true",
+    false_value="false",
+)
+
+_MYSQL = _Dialect(
+    null_type="NULL",
+    num_types=("INTEGER", "DOUBLE", "DECIMAL"),
+    num_cast="DOUBLE",
+    int_types=("INTEGER",),
+    int_cast="SIGNED",
+    int_guard=None,
+    string_type="STRING",
+    bool_type="BOOLEAN",
+    true_value="true",
+    false_value="false",
+)
+
+
+def _bind(compiler: SQLCompiler, value: object, sa_type: TypeEngine[Any], **kw: Any) -> str:
+    param = bindparam(None, value, type_=sa_type)
+    return compiler.process(param, **kw)
+
+
+def _type_check(typeof: str, types: tuple[str, ...]) -> str:
+    if len(types) == 1:
+        return f"{typeof} = '{types[0]}'"
+    quoted = ", ".join(f"'{type_name}'" for type_name in types)
+    return f"{typeof} IN ({quoted})"
+
+
+def _build_clause(compiler: SQLCompiler, typeof: str, extract: str, value: object, dialect: _Dialect, **kw: Any) -> str:
+    if value is None:
+        return f"{typeof} = '{dialect.null_type}'"
+    if isinstance(value, bool):
+        bool_str = dialect.true_value if value else dialect.false_value
+        if dialect.bool_type is None:
+            return f"{typeof} = '{bool_str}'"
+        return f"({typeof} = '{dialect.bool_type}' AND {extract} = '{bool_str}')"
+    if isinstance(value, int):
+        bp = _bind(compiler, value, BigInteger(), **kw)
+        if dialect.int_guard:
+            return (
+                f"(CASE WHEN {_type_check(typeof, dialect.int_types)} AND {extract} ~ {dialect.int_guard} "
+                f"THEN CAST({extract} AS {dialect.int_cast}) END = {bp})"
+            )
+        return f"({_type_check(typeof, dialect.int_types)} AND CAST({extract} AS {dialect.int_cast}) = {bp})"
+    if isinstance(value, float):
+        bp = _bind(compiler, value, Float(), **kw)
+        return f"({_type_check(typeof, dialect.num_types)} AND CAST({extract} AS {dialect.num_cast}) = {bp})"
+    bp = _bind(compiler, str(value), String(), **kw)
+    return f"({typeof} = '{dialect.string_type}' AND {extract} = {bp})"
+
+
+@compiles(JsonMatch, "sqlite")
+def _compile_sqlite(element: JsonMatch, compiler: SQLCompiler, **kw: Any) -> str:
+    if not validate_metadata_filter_key(element.key):
+        raise ValueError(f"Key escaped validation: {element.key!r}")
+    col = compiler.process(element.column, **kw)
+    path = f'$."{element.key}"'
+    typeof = f"json_type({col}, '{path}')"
+    extract = f"json_extract({col}, '{path}')"
+    return _build_clause(compiler, typeof, extract, element.value, _SQLITE, **kw)
+
+
+@compiles(JsonMatch, "postgresql")
+def _compile_postgres(element: JsonMatch, compiler: SQLCompiler, **kw: Any) -> str:
+    if not validate_metadata_filter_key(element.key):
+        raise ValueError(f"Key escaped validation: {element.key!r}")
+    col = compiler.process(element.column, **kw)
+    typeof = f"json_typeof({col} -> '{element.key}')"
+    extract = f"({col} ->> '{element.key}')"
+    return _build_clause(compiler, typeof, extract, element.value, _POSTGRES, **kw)
+
+
+@compiles(JsonMatch, "mysql")
+def _compile_mysql(element: JsonMatch, compiler: SQLCompiler, **kw: Any) -> str:
+    if not validate_metadata_filter_key(element.key):
+        raise ValueError(f"Key escaped validation: {element.key!r}")
+    col = compiler.process(element.column, **kw)
+    path = f'$."{element.key}"'
+    typeof = f"JSON_TYPE(JSON_EXTRACT({col}, '{path}'))"
+    extract = f"JSON_UNQUOTE(JSON_EXTRACT({col}, '{path}'))"
+    return _build_clause(compiler, typeof, extract, element.value, _MYSQL, **kw)
+
+
+@compiles(JsonMatch)
+def _compile_default(element: JsonMatch, compiler: SQLCompiler, **kw: Any) -> str:
+    raise NotImplementedError(f"JsonMatch supports sqlite, postgresql, and mysql; got dialect: {compiler.dialect.name}")
+
+
+def json_match(column: ColumnElement[Any], key: str, value: object) -> JsonMatch:
+    return JsonMatch(column, key, value)