Various bug fixes. Still trying to fix cartesian issue on search.

crudkit/engines.py

@@ -1,7 +1,8 @@
+# engines.py
 from __future__ import annotations
 from typing import Type, Optional
-from sqlalchemy import create_engine
-from sqlalchemy.orm import sessionmaker
+from sqlalchemy import create_engine, event
+from sqlalchemy.orm import sessionmaker, raiseload, Mapper, RelationshipProperty
 from .backend import make_backend_info, BackendInfo
 from .config import Config, get_config
 from ._sqlite import apply_sqlite_pragmas
@@ -12,15 +13,31 @@ def build_engine(config_cls: Type[Config] | None = None):
     apply_sqlite_pragmas(engine, config_cls.SQLITE_PRAGMAS)
     return engine
 
+def _install_nplus1_guards(SessionMaker, *, strict: bool):
+    if not strict:
+        return
+
+    @event.listens_for(SessionMaker, "do_orm_execute")
+    def _add_global_raiseload(execute_state):
+        stmt = execute_state.statement
+        # Only touch ORM statements (have column_descriptions)
+        if getattr(stmt, "column_descriptions", None):
+            execute_state.statement = stmt.options(raiseload("*"))
+
 def build_sessionmaker(config_cls: Type[Config] | None = None, engine=None):
     config_cls = config_cls or get_config(None)
     engine = engine or build_engine(config_cls)
-    return sessionmaker(bind=engine, **config_cls.session_kwargs())
+    SessionMaker = sessionmaker(bind=engine, **config_cls.session_kwargs())
+
+    # Toggle with a config flag; default off so you can turn it on when ready
+    strict = bool(getattr(config_cls, "STRICT_NPLUS1", False))
+    _install_nplus1_guards(SessionMaker, strict=strict)
+    return SessionMaker
 
 class CRUDKitRuntime:
     """
     Lightweight container so CRUDKit can be given either:
-        - prebuild engine/sessionmaker, or
+        - prebuilt engine/sessionmaker, or
         - a Config to build them lazily
     """
     def __init__(self, *, engine=None, session_factory=None, config: Optional[Type[Config]] = None):